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Sample records for lysine-derived antifibrinolytic drugs

  1. Antifibrinolytics in liver surgery

    Directory of Open Access Journals (Sweden)

    Jalpa Makwana

    2010-01-01

    Full Text Available Hyperfibrinolysis, a known complication of liver surgery and orthotopic liver transplantation (OLT, plays a significant role in blood loss. This fact justifies the use of antifibrinolytic drugs during these procedures. Two groups of drug namely lysine analogues [epsilon aminocaproic acid (EACA and tranexamic acid (TA] and serine-protease-inhibitors (aprotinin are frequently used for this purpose. But uniform data or guidelines on the type of antifibrinolytic drugs to be used, their indications and correct dose, is still insufficient. Antifibrinolytics behave like a double-edged sword. On one hand, there are benefits of less transfusion requirements but on the other hand there is potential complication like thromboembolism, which has been reported in several studies. We performed a systematic search in PubMed and Cochrane Library, and we included studies wherein antifibrinolytic drugs (EACA, TA, or aprotinin were compared with each other or with controls/placebo. We analysed factors like intraoperative red blood cell and fresh frozen plasma requirements, the perioperative incidence of hepatic artery thrombosis, venous thromboembolic events and mortality. Among the three drugs, EACA is least studied. Use of extensively studied drug like aprotinin has been restricted because of its side effects. Haemostatic effect of aprotinin and tranexamic acid has been comparable. However, proper patient selection and individualized treatment for each of them is required. Purpose of this review is to study various clinical trials on antifibrinolytic drugs and address the related issues like benefits claimed and associated potential complications.

  2. Anti-fibrinolytic use for minimising perioperative allogeneic blood transfusion

    Science.gov (United States)

    Henry, David A; Carless, Paul A; Moxey, Annette J; O’Connell, Dianne; Stokes, Barrie J; Fergusson, Dean A; Ker, Katharine

    2014-01-01

    a non-significant increase in the risk of myocardial infarction (RR 1.11 95% CI 0.82, 1.50). Most of the data contributing to this added risk came from a single study - the BART trial (2008). Authors’ conclusions Anti-fibrinolytic drugs provide worthwhile reductions in blood loss and the receipt of allogeneic red cell transfusion. Aprotinin appears to be slightly more effective than the lysine analogues in reducing blood loss and the receipt of blood transfusion. However, head to head comparisons show a lower risk of death with lysine analogues when compared with aprotinin. The lysine analogues are effective in reducing blood loss during and after surgery, and appear to be free of serious adverse effects. PMID:21412876

  3. Pharmacological strategies for blood conservation in cardiac surgery: erythropoietin and antifibrinolytics.

    Science.gov (United States)

    Hardy, J F

    2001-04-01

    We review the clinically important benefits of the two principal pharmacological strategies, erythropoietin (EPO) and antifibrinolytics (aprotinin and lysine analogues), to decrease transfusion of allogeneic blood products (ABP) during and after cardiac surgery. Articles were selected from an ongoing review of the literature, with special attention to meta-analyses dealing with EPO and/or antifibrinolytics and cardiac surgery. The few studies available include a number of patients insufficient to allow definitive conclusions on the benefits of EPO in cardiac surgery. Further studies are required to determine the optimal dose of EPO and to compare its cost-effectiveness with other blood sparing strategies in this context. Both aprotinin and lysine analogues effectively decrease ABP transfusions and the incidence of re-thoracotomy. In addition, high-dose aprotinin reduces cerebrovascular morbidity and mortality after cardiopulmonary bypass. Several mechanisms have been put forward to explain these beneficial effects, some of which could well be common to all antifibrinolytics. The clinical benefits of aprotinin's unique anti-inflammatory effect are not entirely clear but the finding that it reduces the incidence of stroke and death is certainly a major argument in favor of its utilization. Yet, we have to ensure that aprotinin's benefits are not offset by side-effects such as allergy. We still need large scale studies to definitely confirm the benefits and exclude the deleterious effects of these drugs on outcomes other than ABP requirements. At present, aprotinin is the only agent that has been shown to reduce the risk of cerebrovascular accident and mortality after cardiac surgery in adults.

  4. Antifibrinolytics in cardiac surgery

    Directory of Open Access Journals (Sweden)

    Achal Dhir

    2013-01-01

    Full Text Available Cardiac surgery exerts a significant strain on the blood bank services and is a model example in which a multi-modal blood-conservation strategy is recommended. Significant bleeding during cardiac surgery, enough to cause re-exploration and/or blood transfusion, increases morbidity and mortality. Hyper-fibrinolysis is one of the important contributors to increased bleeding. This knowledge has led to the use of anti-fibrinolytic agents especially in procedures performed under cardiopulmonary bypass. Nothing has been more controversial in recent times than the aprotinin controversy. Since the withdrawal of aprotinin from the world market, the choice of antifibrinolytic agents has been limited to lysine analogues either tranexamic acid (TA or epsilon amino caproic acid (EACA. While proponents of aprotinin still argue against its non-availability. Health Canada has approved its use, albeit under very strict regulations. Antifibrinolytic agents are not without side effects and act like double-edged swords, the stronger the anti-fibrinolytic activity, the more serious the side effects. Aprotinin is the strongest in reducing blood loss, blood transfusion, and possibly, return to the operating room after cardiac surgery. EACA is the least effective, while TA is somewhere in between. Additionally, aprotinin has been implicated in increased mortality and maximum side effects. TA has been shown to increase seizure activity, whereas, EACA seems to have the least side effects. Apparently, these agents do not differentiate between pathological and physiological fibrinolysis and prevent all forms of fibrinolysis leading to possible thrombotic side effects. It would seem prudent to select the right agent knowing its risk-benefit profile for a given patient, under the given circumstances.

  5. Expanding lysine industry: industrial biomanufacturing of lysine and its derivatives.

    Science.gov (United States)

    Cheng, Jie; Chen, Peng; Song, Andong; Wang, Dan; Wang, Qinhong

    2018-04-13

    L-Lysine is widely used as a nutrition supplement in feed, food, and beverage industries as well as a chemical intermediate. At present, great efforts are made to further decrease the cost of lysine to make it more competitive in the markets. Furthermore, lysine also shows potential as a feedstock to produce other high-value chemicals for active pharmaceutical ingredients, drugs, or materials. In this review, the current biomanufacturing of lysine is first presented. Second, the production of novel derivatives from lysine is discussed. Some chemicals like L-pipecolic acid, cadaverine, and 5-aminovalerate already have been obtained at a lab scale. Others like 6-aminocaproic acid, valerolactam, and caprolactam could be produced through a biological and chemical coupling pathway or be synthesized by a hypothetical pathway. This review demonstrates an active and expansive lysine industry, and these green biomanufacturing strategies could also be applied to enhance the competitiveness of other amino acid industry.

  6. Synthesis and Anchoring of Antineoplastic Ferrocene and Phthalocyanine Derivatives on Water-Soluble Polymeric Drug Carriers Derived from Lysine and Aspartic Acid

    OpenAIRE

    Maree, M. David; Neuse, Eberhard W.; Erasmus, Elizabeth; Swarts, Jannie C.

    2007-01-01

    The general synthetic strategy towards water-soluble biodegradable drug carriers and the properties that they must have are discussed. The syntheses of water-soluble biodegradable copolymers of lysine and aspartic acid as potential drug-delivering devices, having amine-functionalised side chains are then described. Covalent anchoring of carboxylic acid derivatives of the antineoplastic ferrocene and photodynamically active phthalocyanine moieties to the amine-containing drug carrier copolymer...

  7. Effect of antifibrinolytic drugs on transfusion requirement and blood loss during orthotopic liver transplantation: Results from a single center

    Directory of Open Access Journals (Sweden)

    Devi A

    2008-01-01

    Full Text Available Background: During orthotopic liver transplantation (OLT, activation of the fibrinolytic system can contribute significantly to perioperative bleeding. Prophylactic administration of antifibrinolytic agents has been shown to reduce blood loss and the need for allogenic transfusion. Objective: To study the effect of antifibrinolytics on requirement of blood components, blood loss and operative time during OLT in patients with end stage liver disease, reporting to a single centre. Materials and Methods: Consecutive patients who underwent OLT at this centre during the period February 2003-October 2007 were the subjects of this study. Based on the individual anesthesiologist′s preference, patients were assigned to receive either two million units of aprotinin (AP as a bolus followed by 5,00,000 units/hour or 10 mg/kg tranexamic acid (TAas a bolus followed by 10 mg/kg every six to eight hours, administered from the induction till the end of the surgery. Transfusion policy was standardized in all patients. Intraoperative red cell salvage was done wherever possible. The effect of these two antifibrinolytic drugs on transfusion requirement was evaluated as a whole and in a sub group of patients from each treatment group and compared with a concurrent control group that did not receive antifibrinolytic drugs. Results: Fifty patients (40 M / 10 F, 44 adults, 6 pediatric patients underwent OLT in the study period. Fourteen patients were given AP, 25 patients were given TA and 11 patients did not receive any of the agents(control group. The median volume of total blood components transfused in antifibrinolytic group (n=39 was 4540 ml(0-19,200ml, blood loss 5 l(0.7-35l and operative time 9h (4.5-17h and that of control group(n=11 was 5700 ml(0-15,500ml, 10 l(0.6-25 l and 9h (6.4-15.8h respectively. The median volume of blood transfusions, blood loss and operative time was lesser in AP group(n=14 than that of TA group(n=25. Conclusion: There is definite

  8. Antifibrinolytic drugs for treating primary postpartum haemorrhage.

    Science.gov (United States)

    Shakur, Haleema; Beaumont, Danielle; Pavord, Sue; Gayet-Ageron, Angele; Ker, Katharine; Mousa, Hatem A

    2018-02-20

    Postpartum haemorrhage (PPH) - heaving bleeding within the first 24 hours after giving birth - is one of the main causes of death of women after childbirth. Antifibrinolytics, primarily tranexamic acid (TXA), have been shown to reduce bleeding in surgery and safely reduces mortality in trauma patients with bleeding without increasing the risk of adverse events.An earlier Cochrane review on treatments for primary PPH covered all the various available treatments - that review has now been split by types of treatment. This new review concentrates only on the use of antifibrinolytic drugs for treating primary PPH. To determine the effectiveness and safety of antifibrinolytic drugs for treating primary PPH. We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (28 May 2017) and reference lists of retrieved studies. Randomised controlled trials (RCTs), including cluster-randomised trials of antifibrinolytic drugs (aprotinin, TXA, epsilon-aminocaproic acid (EACA) and aminomethylbenzoic acid, administered by whatever route) for primary PPH in women.Participants in the trials were women after birth following a pregnancy of at least 24 weeks' gestation with a diagnosis of PPH, regardless of mode of birth (vaginal or caesarean section) or other aspects of third stage management.We have not included quasi-randomised trials, or cross-over studies. Studies reported as abstracts have not been included if there was insufficient information to allow assessment of risk of bias.In this review we only identified studies looking at TXA. Two review authors independently extracted data from each study using an agreed form. We entered data into Review Manager software and checked for accuracy.For key review outcomes, we rated the quality of the evidence as 'high', 'moderate', 'low' or 'very low' according to the GRADE approach. Three trials (20,412 women) met our inclusion criteria. Two trials

  9. Lysine and pipecolic acid and some of their derivatives show anticonvulsant activity, and stimulation of benzodiazepine receptor activity

    International Nuclear Information System (INIS)

    Chang, Yung-Feng; Gao, Xue-Min

    1989-01-01

    Benzodiazepines are one of the most widely prescribed drugs in the treatment of anxiety, epilepsy and muscle tension. The natural products lysine and pipecolic acid known to be present in the animal, plant and microorganism, have been shown to be anticonvulsant against pentetrazol (PTZ)-induced seizures in mice. Methyl and ethyl esters of L-lysine and the N-isopropanol derivative of pipecolic acid appear to increase the anticonvulsant potency of the parent compounds, presumably due to their increase in hydrophobicity. Lysine and pipecolic acid showed significant stimulation of specific [ 3 H]flunitrazepam (FZ) binding to mouse brain membranes. This stimulation was enhanced by chloride ions and stereospecific with L-isomer having higher effect. The dose-dependent anticonvulsant activity of lysine and pipecolic acid, and their stimulation of [ 3 H]FZ binding appear to be correlated. The antiepileptic activity lysine, pipecolic acid and their derivatives therefore may be mediated through the γ-aminobutyric acid-benzodiazepine receptor complex

  10. Antifibrinolytics for heavy menstrual bleeding.

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    Bryant-Smith, Alison C; Lethaby, Anne; Farquhar, Cindy; Hickey, Martha

    2018-04-15

    Heavy menstrual bleeding (HMB) is an important physical and social problem for women. Oral treatment for HMB includes antifibrinolytic drugs, which are designed to reduce bleeding by inhibiting clot-dissolving enzymes in the endometrium.Historically, there has been some concern that using the antifibrinolytic tranexamic acid (TXA) for HMB may increase the risk of venous thromboembolic disease. This is an umbrella term for deep venous thrombosis (blood clots in the blood vessels in the legs) and pulmonary emboli (blood clots in the blood vessels in the lungs). To determine the effectiveness and safety of antifibrinolytic medications as a treatment for heavy menstrual bleeding. We searched the Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO and two trials registers in November 2017, together with reference checking and contact with study authors and experts in the field. We included randomized controlled trials (RCTs) comparing antifibrinolytic agents versus placebo, no treatment or other medical treatment in women of reproductive age with HMB. Twelve studies utilised TXA and one utilised a prodrug of TXA (Kabi). We used standard methodological procedures expected by Cochrane. The primary review outcomes were menstrual blood loss (MBL), improvement in HMB, and thromboembolic events. We included 13 RCTs (1312 participants analysed). The evidence was very low to moderate quality: the main limitations were risk of bias (associated with lack of blinding, and poor reporting of study methods), imprecision and inconsistency.Antifibrinolytics (TXA or Kabi) versus no treatment or placeboWhen compared with a placebo, antifibrinolytics were associated with reduced mean blood loss (MD -53.20 mL per cycle, 95% CI -62.70 to -43.70; I² = 8%; 4 RCTs, participants = 565; moderate-quality evidence) and higher rates of improvement (RR 3.34, 95% CI 1.84 to 6.09; 3 RCTS, participants = 271; moderate-quality evidence). This suggests that

  11. The antifibrinolytic drug tranexamic acid reduces liver injury and fibrosis in a mouse model of chronic bile duct injury.

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    Joshi, Nikita; Kopec, Anna K; Towery, Keara; Williams, Kurt J; Luyendyk, James P

    2014-06-01

    Hepatic fibrin deposition has been shown to inhibit hepatocellular injury in mice exposed to the bile duct toxicant α-naphthylisothiocyanate (ANIT). Degradation of fibrin clots by fibrinolysis controls the duration and extent of tissue fibrin deposition. Thus, we sought to determine the effect of treatment with the antifibrinolytic drug tranexamic acid (TA) and plasminogen activator inhibitor-1 (PAI-1) deficiency on ANIT-induced liver injury and fibrosis in mice. Plasmin-dependent lysis of fibrin clots was impaired in plasma from mice treated with TA (1200 mg/kg i.p., administered twice daily). Prophylactic TA administration reduced hepatic inflammation and hepatocellular necrosis in mice fed a diet containing 0.025% ANIT for 2 weeks. Hepatic type 1 collagen mRNA expression and deposition increased markedly in livers of mice fed ANIT diet for 4 weeks. To determine whether TA treatment could inhibit this progression of liver fibrosis, mice were fed ANIT diet for 4 weeks and treated with TA for the last 2 weeks. Interestingly, TA treatment largely prevented increased deposition of type 1 collagen in livers of mice fed ANIT diet for 4 weeks. In contrast, biliary hyperplasia/inflammation and liver fibrosis were significantly increased in PAI-1(-/-) mice fed ANIT diet for 4 weeks. Overall, the results indicate that fibrinolytic activity contributes to ANIT diet-induced liver injury and fibrosis in mice. In addition, these proof-of-principle studies suggest the possibility that therapeutic intervention with an antifibrinolytic drug could form a novel strategy to prevent or reduce liver injury and fibrosis in patients with liver disease.

  12. Antimicrobial activity of bovine NK-lysin-derived peptides on Mycoplasma bovis

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    Antimicrobial peptides (AMPs) are a diverse group of molecules which play an important role in the innate immune response. Bovine NK-lysins, a type of AMP, have been predominantly found in the granules of cytotoxic T-lymphocytes and NK-cells. Bovine NK-lysin-derived peptides demonstrate antimicrobia...

  13. Antifibrinolytic treatment in subarachnoid hemorrhage

    NARCIS (Netherlands)

    Vermeulen, M.; Lindsay, K. W.; Murray, G. D.; Cheah, F.; Hijdra, A.; Muizelaar, J. P.; Schannong, M.; Teasdale, G. M.; van Crevel, H.; van Gijn, J.

    1984-01-01

    We enrolled 479 patients with subarachnoid hemorrhage in a multicenter, randomized, double-blind, placebo-controlled trial to determine whether treatment with the antifibrinolytic agent tranexamic acid improves outcome by preventing rebleeding. At three months there was no statistical difference

  14. Native mass spectrometry and ion mobility characterization of trastuzumab emtansine, a lysine-linked antibody drug conjugate.

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    Marcoux, Julien; Champion, Thierry; Colas, Olivier; Wagner-Rousset, Elsa; Corvaïa, Nathalie; Van Dorsselaer, Alain; Beck, Alain; Cianférani, Sarah

    2015-08-01

    Antibody-drug conjugates (ADCs) are biochemotherapeutics consisting of a cytotoxic chemical drug linked covalently to a monoclonal antibody. Two main classes of ADCs, namely cysteine and lysine conjugates, are currently available on the market or involved in clinical trials. The complex structure and heterogeneity of ADCs makes their biophysical characterization challenging. For cysteine conjugates, hydrophobic interaction chromatography is the gold standard technique for studying drug distribution, the naked antibody content, and the average drug to antibody ratio (DAR). For lysine ADC conjugates on the other hand, which are not amenable to hydrophobic interaction chromatography because of their higher heterogeneity, denaturing mass spectrometry (MS) and UV/Vis spectroscopy are the most powerful approaches. We report here the use of native MS and ion mobility (IM-MS) for the characterization of trastuzumab emtansine (T-DM1, Kadcyla(®)). This lysine conjugate is currently being considered for the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer, and combines the anti-HER2 antibody trastuzumab (Herceptin(®)), with the cytotoxic microtubule-inhibiting maytansine derivative, DM1. We show that native MS combined with high-resolution measurements and/or charge reduction is beneficial in terms of the accurate values it provides of the average DAR and the drug load profiles. The use of spectral deconvolution is discussed in detail. We report furthermore the use of native IM-MS to directly determine DAR distribution profiles and average DAR values, as well as a molecular modeling investigation of positional isomers in T-DM1. © 2015 The Protein Society.

  15. Discovery and Evaluation of Anti-Fibrinolytic Plasmin Inhibitors Derived from 5-(4-Piperidyl)isoxazol-3-ol (4-PIOL)

    DEFF Research Database (Denmark)

    Schmidt, Thomas C.; Eriksson, Per-Olof; Gustafsson, David

    2017-01-01

    Inhibition of plasmin has been found to effectively reduce fibrinolysis and to avoid hemorrhage. This can be achieved by addressing its kringle 1 domain with the known drug and lysine analogue tranexamic acid. Guided by shape similarities toward a previously discovered lead compound, 5-(4-piperidyl...

  16. Genipin-cross-linked poly(L-lysine)-based hydrogels: synthesis, characterization, and drug encapsulation.

    Science.gov (United States)

    Wang, Steven S S; Hsieh, Ping-Lun; Chen, Pei-Shan; Chen, Yu-Tien; Jan, Jeng-Shiung

    2013-11-01

    Genipin-cross-linked hydrogels composed of biodegradable and pH-sensitive cationic poly(L-lysine) (PLL), poly(L-lysine)-block-poly(L-alanine) (PLL-b-PLAla), and poly(L-lysine)-block-polyglycine (PLL-b-PGly) polypeptides were synthesized, characterized, and used as carriers for drug delivery. These polypeptide hydrogels can respond to pH-stimulus and their gelling and mechanical properties, degradation rate, and drug release behavior can be tuned by varying polypeptide composition and cross-linking degree. Comparing with natural polymers, the synthetic polypeptides with well-defined chain length and composition can warrant the preparation of the hydrogels with tunable properties to meet the criteria for specific biomedical applications. These hydrogels composed of natural building blocks exhibited good cell compatibility and enzyme degradability and can support cell attachment/proliferation. The evaluation of these hydrogels for in vitro drug release revealed that the controlled release profile was a biphasic pattern with a mild burst release and a moderate release rate thereafter, suggesting the drug molecules were encapsulated inside the gel matrix. With the versatility of polymer chemistry and conjugation of functional moieties, it is expected these hydrogels can be useful for biomedical applications such as polymer therapeutics and tissue engineering. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Antifibrinolytic amino acids for upper gastrointestinal bleeding in people with acute or chronic liver disease.

    Science.gov (United States)

    Martí-Carvajal, Arturo J; Solà, Ivan

    2015-06-09

    Upper gastrointestinal bleeding is one of the most frequent causes of morbidity and mortality in the course of liver cirrhosis. People with liver disease frequently have haemostatic abnormalities such as hyperfibrinolysis. Therefore, antifibrinolytic amino acids have been proposed to be used as supplementary interventions alongside any of the primary treatments for upper gastrointestinal bleeding in people with liver diseases. This is an update of this Cochrane review. To assess the beneficial and harmful effects of antifibrinolytic amino acids for upper gastrointestinal bleeding in people with acute or chronic liver disease. We searched The Cochrane Hepato-Biliary Controlled Trials Register (February 2015), Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 2 of 12, 2015), MEDLINE (Ovid SP) (1946 to February 2015), EMBASE (Ovid SP) (1974 to February 2015), Science Citation Index EXPANDED (1900 to February 2015), LILACS (1982 to February 2015), World Health Organization Clinical Trials Search Portal (accessed 26 February 2015), and the metaRegister of Controlled Trials (accessed 26 February 2015). We scrutinised the reference lists of the retrieved publications. Randomised clinical trials irrespective of blinding, language, or publication status for assessment of benefits and harms. Observational studies for assessment of harms. We planned to summarise data from randomised clinical trials using standard Cochrane methodologies and assessed according to the GRADE approach. We found no randomised clinical trials assessing antifibrinolytic amino acids for treating upper gastrointestinal bleeding in people with acute or chronic liver disease. We did not identify quasi-randomised, historically controlled, or observational studies in which we could assess harms. This updated Cochrane review identified no randomised clinical trials assessing the benefits and harms of antifibrinolytic amino acids for upper gastrointestinal bleeding in people with acute or

  18. Thermo-sensitive liposomes loaded with doxorubicin and lysine modified single-walled carbon nanotubes as tumor-targeting drug delivery system.

    Science.gov (United States)

    Zhu, Xiali; Xie, Yingxia; Zhang, Yingjie; Huang, Heqing; Huang, Shengnan; Hou, Lin; Zhang, Huijuan; Li, Zhi; Shi, Jinjin; Zhang, Zhenzhong

    2014-11-01

    This report focuses on the thermo-sensitive liposomes loaded with doxorubicin and lysine-modified single-walled carbon nanotube drug delivery system, which was designed to enhance the anti-tumor effect and reduce the side effects of doxorubicin. Doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes was prepared by reverse-phase evaporation method, the mean particle size was 232.0 ± 5.6 nm, and drug entrapment efficiency was 86.5 ± 3.7%. The drug release test showed that doxorubicin released more quickly at 42℃ than at 37℃. Compared with free doxorubicin, doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes could efficiently cross the cell membranes and afford higher anti-tumor efficacy on the human hepatic carcinoma cell line (SMMC-7721) cells in vitro. For in vivo experiments, the relative tumor volumes of the sarcomaia 180-bearing mice in thermo-sensitive liposomes group and doxorubicin group were significantly smaller than those of N.S. group. Meanwhile, the combination of near-infrared laser irradiation at 808 nm significantly enhanced the tumor growth inhibition both on SMMC-7721 cells and the sarcomaia 180-bearing mice. The quality of life such as body weight, mental state, food and water intake of sarcomaia 180 tumor-bearing mice treated with doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes were much higher than those treated with doxorubicin. In conclusion, doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes combined with near-infrared laser irradiation at 808 nm may potentially provide viable clinical strategies for targeting delivery of anti-cancer drugs. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  19. The effectiveness and safety of antifibrinolytics in patients with acute intracranial haemorrhage: statistical analysis plan for an individual patient data meta-analysis

    OpenAIRE

    Ker, Katharine; Prieto-Merino, David; Sprigg, Nikola; Mahmood, Abda; Bath, Philip; Kang Law, Zhe; Flaherty, Katie; Roberts, Ian

    2017-01-01

    Introduction: The Antifibrinolytic Trialists Collaboration aims to increase knowledge about the effectiveness and safety of antifibrinolytic treatment by conducting individual patient data (IPD) meta-analyses of randomised trials. This article presents the statistical analysis plan for an IPD meta-analysis of the effects of antifibrinolytics for acute intracranial haemorrhage. Methods: The protocol for the IPD meta-analysis has been registered with PROSPERO (CRD42016052155). We will conduct a...

  20. Structural basis for the site-specific incorporation of lysine derivatives into proteins.

    Directory of Open Access Journals (Sweden)

    Veronika Flügel

    Full Text Available Posttranslational modifications (PTMs of proteins determine their structure-function relationships, interaction partners, as well as their fate in the cell and are crucial for many cellular key processes. For instance chromatin structure and hence gene expression is epigenetically regulated by acetylation or methylation of lysine residues in histones, a phenomenon known as the 'histone code'. Recently it was shown that these lysine residues can furthermore be malonylated, succinylated, butyrylated, propionylated and crotonylated, resulting in significant alteration of gene expression patterns. However the functional implications of these PTMs, which only differ marginally in their chemical structure, is not yet understood. Therefore generation of proteins containing these modified amino acids site specifically is an important tool. In the last decade methods for the translational incorporation of non-natural amino acids using orthogonal aminoacyl-tRNA synthetase (aaRS:tRNAaaCUA pairs were developed. A number of studies show that aaRS can be evolved to use non-natural amino acids and expand the genetic code. Nevertheless the wild type pyrrolysyl-tRNA synthetase (PylRS from Methanosarcina mazei readily accepts a number of lysine derivatives as substrates. This enzyme can further be engineered by mutagenesis to utilize a range of non-natural amino acids. Here we present structural data on the wild type enzyme in complex with adenylated ε-N-alkynyl-, ε-N-butyryl-, ε-N-crotonyl- and ε-N-propionyl-lysine providing insights into the plasticity of the PylRS active site. This shows that given certain key features in the non-natural amino acid to be incorporated, directed evolution of this enzyme is not necessary for substrate tolerance.

  1. Secapin, a bee venom peptide, exhibits anti-fibrinolytic, anti-elastolytic, and anti-microbial activities.

    Science.gov (United States)

    Lee, Kwang Sik; Kim, Bo Yeon; Yoon, Hyung Joo; Choi, Yong Soo; Jin, Byung Rae

    2016-10-01

    Bee venom contains a variety of peptide constituents that have various biological, toxicological, and pharmacological actions. However, the biological actions of secapin, a venom peptide in bee venom, remain largely unknown. Here, we provide the evidence that Asiatic honeybee (Apis cerana) secapin (AcSecapin-1) exhibits anti-fibrinolytic, anti-elastolytic, and anti-microbial activities. The recombinant mature AcSecapin-1 peptide was expressed in baculovirus-infected insect cells. AcSecapin-1 functions as a serine protease inhibitor-like peptide that has inhibitory effects against plasmin, elastases, microbial serine proteases, trypsin, and chymotrypsin. Consistent with these functions, AcSecapin-1 inhibited the plasmin-mediated degradation of fibrin to fibrin degradation products, thus indicating the role of AcSecapin-1 as an anti-fibrinolytic agent. AcSecapin-1 also inhibited both human neutrophil and porcine pancreatic elastases. Furthermore, AcSecapin-1 bound to bacterial and fungal surfaces and exhibited anti-microbial activity against fungi and gram-positive and gram-negative bacteria. Taken together, our data demonstrated that the bee venom peptide secapin has multifunctional roles as an anti-fibrinolytic agent during fibrinolysis and an anti-microbial agent in the innate immune response. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. The effectiveness and safety of antifibrinolytics in patients with acute intracranial haemorrhage: statistical analysis plan for an individual patient data meta-analysis.

    Science.gov (United States)

    Ker, Katharine; Prieto-Merino, David; Sprigg, Nikola; Mahmood, Abda; Bath, Philip; Kang Law, Zhe; Flaherty, Katie; Roberts, Ian

    2017-01-01

    Introduction : The Antifibrinolytic Trialists Collaboration aims to increase knowledge about the effectiveness and safety of antifibrinolytic treatment by conducting individual patient data (IPD) meta-analyses of randomised trials. This article presents the statistical analysis plan for an IPD meta-analysis of the effects of antifibrinolytics for acute intracranial haemorrhage. Methods : The protocol for the IPD meta-analysis has been registered with PROSPERO (CRD42016052155). We will conduct an individual patient data meta-analysis of randomised controlled trials with 1000 patients or more assessing the effects of antifibrinolytics in acute intracranial haemorrhage. We will assess the effect on two co-primary outcomes: 1) death in hospital at end of trial follow-up, and 2) death in hospital or dependency at end of trial follow-up. The co-primary outcomes will be limited to patients treated within three hours of injury or stroke onset. We will report treatment effects using odds ratios and 95% confidence intervals. We use logistic regression models to examine how the effect of antifibrinolytics vary by time to treatment, severity of intracranial bleeding, and age. We will also examine the effect of antifibrinolytics on secondary outcomes including death, dependency, vascular occlusive events, seizures, and neurological outcomes. Secondary outcomes will be assessed in all patients irrespective of time of treatment. All analyses will be conducted on an intention-to-treat basis. Conclusions : This IPD meta-analysis will examine important clinical questions about the effects of antifibrinolytic treatment in patients with intracranial haemorrhage that cannot be answered using aggregate data. With IPD we can examine how effects vary by time to treatment, bleeding severity, and age, to gain better understanding of the balance of benefit and harms on which to base recommendations for practice.

  3. Excited-State Dynamics of Melamine and Its Lysine Derivative Investigated by Femtosecond Transient Absorption Spectroscopy

    Directory of Open Access Journals (Sweden)

    Yuyuan Zhang

    2016-11-01

    Full Text Available Melamine may have been an important prebiotic information carrier, but its excited-state dynamics, which determine its stability under UV radiation, have never been characterized. The ability of melamine to withstand the strong UV radiation present on the surface of the early Earth is likely to have affected its abundance in the primordial soup. Here, we studied the excited-state dynamics of melamine (a proto-nucleobase and its lysine derivative (a proto-nucleoside using the transient absorption technique with a UV pump, and UV and infrared probe pulses. For melamine, the excited-state population decays by internal conversion with a lifetime of 13 ps without coupling significantly to any photochemical channels. The excited-state lifetime of the lysine derivative is slightly longer (18 ps, but the dominant deactivation pathway is otherwise the same as for melamine. In both cases, the vast majority of excited molecules return to the electronic ground state on the aforementioned time scales, but a minor population is trapped in a long-lived triplet state.

  4. Preparation and evaluation of a novel anticancer drug delivery carrier for 5-Fluorouracil using synthetic bola-amphiphile based on lysine as polar heads

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Beibei [School of Pharmacy, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang 110016 (China); Yuan, Yue, E-mail: hiyueyuan@163.com [School of Pharmacy, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang 110016 (China); Yan, Yun [College of Chemistry and Molecular Engineering, Peking University, 202 Chenfu Road, Beijing 100871 (China); Zhou, Xiaoping [School of Pharmacy, Jilin University, 1266 Fujin Road, Changchun 130021 (China); Li, Yue; Kan, Qiming [School of Pharmacy, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang 110016 (China); Li, Sanming, E-mail: li_sanming@sina.com [School of Pharmacy, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang 110016 (China)

    2017-06-01

    A novel bolaamphiphile surfactant N,N′-(dodecane-1, 12-diyl) bis (2,6-diaminohexanamide) (DADL) was designed and synthesized using L-lysine and 1,12-diaminododecane as the hydrophilic and hydrophobic part, respectively. After separation and purification, the structure of the synthetic bolaamphiphile surfactant was verified by FTIR, MS and {sup 1}H NMR. The synthetic bolaamphiphile was able to self-assemble to form vesicles. After formulation screening, vesicles loaded with 5-Fluorouracil (5-Fu) were prepared with Tween 60 and DADL by sonication and were examined by dynamic light scattering and transmission electron microscopy. Micro-FTIR was applied to investigate the conformation of the bola molecules within the vesicle membrane. The release profile of the vesicles showed a pH-sensitive and sustained release. No significant toxicity was observed in an in vitro cell viability assay. The antitumor efficacy of the 5-Fu-loaded vesicles on H{sub 22} tumor-bearing mice was remarkably high due to the EPR effects. These results show that our novel bolaamphiphile derived from lysine has excellent potential as a pH-sensitive drug carrier. - Highlights: • A novel bolaamphiphile molecule with lysine as hydrophilic part was synthesized. • The synthesized bolaamphiphile could self-assemble to form nano-sized vesicles. • The vesicles were pH-sensitive and have tumor-targeting potential.

  5. Acetanilide and bromoacetyl-lysine derivatives as activators for human histone deacetylase 8.

    Science.gov (United States)

    Mukhtar, Yusif M; Huang, Yajun; Liu, Jiajia; Chen, Di; Zheng, Weiping

    2017-06-01

    In the current study, seven compounds (i.e. 1-7) were found to be novel activators for the N ε -acetyl-lysine deacetylation reaction catalyzed by human histone deacetylase 8 (HDAC8). When assessed with the commercially available HDAC8 peptide substrate Fluor-de-Lys®-HDAC8 that harbors the unnatural 7-amino-4-methylcoumarin (AMC) residue immediately C-terminal to the N ε -acetyl-lysine residue to be deacetylated, our compounds exhibited comparable activation potency to that of TM-2-51, the strongest HDAC8 activator reported in the current literature. However, when assessed with an AMC-less peptide substrate derived from the native HDAC8 non-histone substrate protein Zinc finger protein ZNF318, while our compounds were all found to be able to activate HDAC8 deacetylation reaction, TM-2-51 was found not to be able to. Our compounds also seemed to be largely selective for HDAC8 over other classical HDACs. Moreover, treatment with the strongest activator among our compounds (i.e. 7) was found to decrease the K M of the above AMC-less HDAC8 substrate, while nearly maintaining the k cat of the HDAC8-catalyzed deacetylation on this substrate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. The effectiveness and safety of antifibrinolytics in patients with acute intracranial haemorrhage: statistical analysis plan for an individual patient data meta-analysis [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Katharine Ker

    2018-02-01

    Full Text Available Introduction: The Antifibrinolytic Trialists Collaboration aims to increase knowledge about the effectiveness and safety of antifibrinolytic treatment by conducting individual patient data (IPD meta-analyses of randomised trials. This article presents the statistical analysis plan for an IPD meta-analysis of the effects of antifibrinolytics for acute intracranial haemorrhage. Methods: The protocol for the IPD meta-analysis has been registered with PROSPERO (CRD42016052155. We will conduct an individual patient data meta-analysis of randomised controlled trials with 1000 patients or more assessing the effects of antifibrinolytics in acute intracranial haemorrhage. We will assess the effect on two co-primary outcomes: 1 Death in hospital within 30 days of randomisation, and 2 Death  or dependency at final follow-up within 90 days of randomisation. The co-primary outcomes will be limited to patients treated within three hours of injury or stroke onset. We will report treatment effects using odds ratios and 95% confidence intervals. We use logistic regression models to examine how the effect of antifibrinolytics vary by time to treatment, severity of intracranial bleeding, and age. We will also examine the effect of antifibrinolytics on secondary outcomes including death, dependency, vascular occlusive events, seizures, and neurological outcomes. Secondary outcomes will be assessed in all patients irrespective of time of treatment. All analyses will be conducted on an intention-to-treat basis. Conclusions: This IPD meta-analysis will examine important clinical questions about the effects of antifibrinolytic treatment in patients with intracranial haemorrhage that cannot be answered using aggregate data. With IPD we can examine how effects vary by time to treatment, bleeding severity, and age, to gain better understanding of the balance of benefit and harms on which to base recommendations for practice.

  7. The effectiveness and safety of antifibrinolytics in patients with acute intracranial haemorrhage: statistical analysis plan for an individual patient data meta-analysis [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Katharine Ker

    2017-12-01

    Full Text Available Introduction: The Antifibrinolytic Trialists Collaboration aims to increase knowledge about the effectiveness and safety of antifibrinolytic treatment by conducting individual patient data (IPD meta-analyses of randomised trials. This article presents the statistical analysis plan for an IPD meta-analysis of the effects of antifibrinolytics for acute intracranial haemorrhage. Methods: The protocol for the IPD meta-analysis has been registered with PROSPERO (CRD42016052155. We will conduct an individual patient data meta-analysis of randomised controlled trials with 1000 patients or more assessing the effects of antifibrinolytics in acute intracranial haemorrhage. We will assess the effect on two co-primary outcomes: 1 death in hospital at end of trial follow-up, and 2 death in hospital or dependency at end of trial follow-up. The co-primary outcomes will be limited to patients treated within three hours of injury or stroke onset. We will report treatment effects using odds ratios and 95% confidence intervals. We use logistic regression models to examine how the effect of antifibrinolytics vary by time to treatment, severity of intracranial bleeding, and age. We will also examine the effect of antifibrinolytics on secondary outcomes including death, dependency, vascular occlusive events, seizures, and neurological outcomes. Secondary outcomes will be assessed in all patients irrespective of time of treatment. All analyses will be conducted on an intention-to-treat basis. Conclusions: This IPD meta-analysis will examine important clinical questions about the effects of antifibrinolytic treatment in patients with intracranial haemorrhage that cannot be answered using aggregate data. With IPD we can examine how effects vary by time to treatment, bleeding severity, and age, to gain better understanding of the balance of benefit and harms on which to base recommendations for practice.

  8. Antimicrobial activity of bovine NK-lysin-derived peptides on bovine respiratory pathogen Histophilus somni

    Science.gov (United States)

    Bovine NK-lysins, which are functionally and structurally similar to human granulysin and porcine NK-lysin, are predominantly found in the granules of cytotoxic T-lymphocytes and NK-cells. Although antimicrobial activity of bovine NK-lysin has been assessed for several bacterial pathogens, not all t...

  9. Bioavailability of lysine in heat-treated foods and feedstuffs

    NARCIS (Netherlands)

    McArtney Rutherfurd, S.

    2010-01-01

    During the processing of foodstuffs, lysine can react with other compounds present to form nutritionally unavailable derivatives, the most common example of which are Maillard products. Maillard products can cause serious problems when determining the available lysine content of processed foods or

  10. Preliminary studies of the toxic effects of non-ionic surfactants derived from lysine.

    Science.gov (United States)

    Macián, M; Seguer, J; Infante, M R; Selve, C; Vinardell, M P

    1996-01-08

    The toxic effects of new synthetic monodisperse non-ionic long-chain N alpha, N epsilon-diacyl lysine polyoxyethylene glycol amide compounds with a structural resemblance to natural lecithin phospholipids were studied by the haemolytic method and the test of the chorioallantoic membrane of the hen's egg (HET-CAM). The following compounds were tested: symmetrical N alpha,N epsilon-diacyl lysine homologues (N alpha,N epsilon-dihexanoyl, N alpha,N epsilon-dioctanoyl and N alpha,N epsilon-didecanoyl lysine) with one methyl ether polyoxyethylene glycol chain of different oxyethylene units (dioxyethylene glycol, tetraoxyethylene glycol and hexaoxyethylene glycol) as headgroup; symmetrical N alpha,N epsilon-diacyl lysine homologues with two methyl ether dioxyethylene glycol chains and the asymmetrical N alpha-butanoyl, N epsilon-dodecyl lysine with two hydrophilic methyl ether dioxyethylene glycol chains as headgroup. A commercial (polydisperse) oleoyl polyoxyethylene glycol diethanolamide with an average of eight units of ethylene oxide was used as control. All the synthesized tested compounds appeared to be less haemolytic and less irritant than the control. The synthesized products were studied with regard to their hydrophobic and hydrophilic chains in order to evaluate the influence of their structure on their haemolytic and irritative action. The results of this study show that the acyl chain distribution of these compounds greatly influence toxic effects: the asymmetrical compound N alpha-butanoyl,N epsilon-dodecyl lysine-bis[methyl ether diethylene glycol]amide was found to be the most haemolytic and irritating compound. Among the symmetrical homologues, the shortest-chain compounds N alpha,N epsilon-dihexanoyl lysine methyl ether polyoxyethylene glycol amides present the least haemolytic and irritating activity, independently of the number and length of the hydrophilic methyl ether polyoxyethylene glycol chains. Taking into account their surface activity

  11. Lysine analoga; bereiding en enzymatische hydrolyse van peptide derivaten van lysine en lysine analoga

    NARCIS (Netherlands)

    Tesser, Godefridus Ignatius

    1961-01-01

    De synthese van enkele structuuranaloga van lysine wordt beschreven. Aangetoond wordt dat zij lysine in substraten voor trypsine, cathepsine B en papaine kan vervangen. Daar de structuur van de analoga O-(Beta-aminoaethyl)serine en S-(Beta-aminoaethyl) cysteine die van lysine dicht nadert, wordt

  12. Mass Spectrometric Characterization of Circulating Covalent Protein Adducts Derived from a Drug Acyl Glucuronide Metabolite: Multiple Albumin Adductions in Diclofenac Patients

    Science.gov (United States)

    Hammond, Thomas G.; Meng, Xiaoli; Jenkins, Rosalind E.; Maggs, James L.; Castelazo, Anahi Santoyo; Regan, Sophie L.; Bennett, Stuart N. L.; Earnshaw, Caroline J.; Aithal, Guruprasad P.; Pande, Ira; Kenna, J. Gerry; Stachulski, Andrew V.; Park, B. Kevin

    2014-01-01

    Covalent protein modifications by electrophilic acyl glucuronide (AG) metabolites are hypothetical causes of hypersensitivity reactions associated with certain carboxylate drugs. The complex rearrangements and reactivities of drug AG have been defined in great detail, and protein adducts of carboxylate drugs, such as diclofenac, have been found in liver and plasma of experimental animals and humans. However, in the absence of definitive molecular characterization, and specifically, identification of signature glycation conjugates retaining the glucuronyl and carboxyl residues, it cannot be assumed any of these adducts is derived uniquely or even fractionally from AG metabolites. We have therefore undertaken targeted mass spectrometric analyses of human serum albumin (HSA) isolated from diclofenac patients to characterize drug-derived structures and, thereby, for the first time, have deconstructed conclusively the pathways of adduct formation from a drug AG and its isomeric rearrangement products in vivo. These analyses were informed by a thorough understanding of the reactions of HSA with diclofenac AG in vitro. HSA from six patients without drug-related hypersensitivities had either a single drug-derived adduct or one of five combinations of 2–8 adducts from among seven diclofenac N-acylations and three AG glycations on seven of the protein’s 59 lysines. Only acylations were found in every patient. We present evidence that HSA modifications by diclofenac in vivo are complicated and variable, that at least a fraction of these modifications are derived from the drug’s AG metabolite, and that albumin adduction is not inevitably a causation of hypersensitivity to carboxylate drugs or a coincidental association. PMID:24902585

  13. Oral lysine clonixinate in the acute treatment of migraine: a double-blind placebo-controlled study

    OpenAIRE

    Krymchantowski,Abouch V.; Barbosa,Jackeline S.; Cheim,Celia; Alves,Luiz A.

    2001-01-01

    Several oral nonsteroidal anti-inflammatory drugs (NSAIDs) are effective to treat migraine attacks. Lysine clonixinate (LC) is a NSAID derived from nicotinic acid that has proven to be effective in various pain syndromes such as renal colic and muscular pain. The aim of this double-blind, placebo-controlled study was to evaluate the efficacy of oral LC compared to placebo in the acute treatment of migraine. Sixty four patients with the diagnosis of migraine, according to the IHS criteria, wer...

  14. Oral lysine clonixinate in the acute treatment of migraine: a double-blind placebo-controlled study.

    Science.gov (United States)

    Krymchantowski, A V; Barbosa, J S; Cheim, C; Alves, L A

    2001-03-01

    Several oral nonsteroidal anti-inflammatory drugs (NSAIDs) are effective to treat migraine attacks. Lysine clonixinate (LC) is a NSAID derived from nicotinic acid that has proven to be effective in various pain syndromes such as renal colic and muscular pain. The aim of this double-blind, placebo-controlled study was to evaluate the efficacy of oral LC compared to placebo in the acute treatment of migraine. Sixty four patients with the diagnosis of migraine, according to the IHS criteria, were studied prospectively. Patients received LC or placebo once the headache reached moderate or severe intensity for 6 consecutive attacks. With regard to the moderate attacks, LC was superior than placebo after 1, 2 and 4 hours. The consumption of other rescue medications after 4 hours was significantly higher in the placebo group. With regard to the severe attacks, there was no difference between the active drug group and the placebo group concerning headache intensity and consumption of other rescue medications. We conclude that the NSAID lysine clonixinate is effective in treating moderately severe migraine attacks. It is not superior than placebo in treating severe migraine attacks.

  15. Intravenous lysine clonixinate for the acute treatment of severe migraine attacks: a double-blind, randomized, placebo-controlled study

    OpenAIRE

    Abouch Valenty Krymchantowski, MD, PhD; Marcus Tulius T Silva, MD

    2003-01-01

    Background: Several nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to be effective in the treatment of migraine. However, few commercially available NSAIDs can be administered IV. Lysine clonixinate (LC), an NSAID derived from nicotinic acid, has been proved effective in various algesic syndromes (eg, renal colic, muscular pain, nerve compression, odontalgia). The oral formulation of LC has been shown to be effective in the treatment of migraine of moderate severity. Objective:...

  16. Drug Nanoparticle Formulation Using Ascorbic Acid Derivatives

    Directory of Open Access Journals (Sweden)

    Kunikazu Moribe

    2011-01-01

    Full Text Available Drug nanoparticle formulation using ascorbic acid derivatives and its therapeutic uses have recently been introduced. Hydrophilic ascorbic acid derivatives such as ascorbyl glycoside have been used not only as antioxidants but also as food and pharmaceutical excipients. In addition to drug solubilization, drug nanoparticle formation was observed using ascorbyl glycoside. Hydrophobic ascorbic acid derivatives such as ascorbyl mono- and di-n-alkyl fatty acid derivatives are used either as drugs or carrier components. Ascorbyl n-alkyl fatty acid derivatives have been formulated as antioxidants or anticancer drugs for nanoparticle formulations such as micelles, microemulsions, and liposomes. ASC-P vesicles called aspasomes are submicron-sized particles that can encapsulate hydrophilic drugs. Several transdermal and injectable formulations of ascorbyl n-alkyl fatty acid derivatives were used, including ascorbyl palmitate.

  17. Efficient Production of Enantiopure d-Lysine from l-Lysine by a Two-Enzyme Cascade System

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2016-10-01

    Full Text Available The microbial production of d-lysine has been of great interest as a medicinal raw material. Here, a two-step process for d-lysine production from l-lysine by the successive microbial racemization and asymmetric degradation with lysine racemase and decarboxylase was developed. The whole-cell activities of engineered Escherichia coli expressing racemases from the strains Proteus mirabilis (LYR and Lactobacillus paracasei (AAR were first investigated comparatively. When the strain BL21-LYR with higher racemization activity was employed, l-lysine was rapidly racemized to give dl-lysine, and the d-lysine yield was approximately 48% after 0.5 h. Next, l-lysine was selectively catabolized to generate cadaverine by lysine decarboxylase. The comparative analysis of the decarboxylation activities of resting whole cells, permeabilized cells, and crude enzyme revealed that the crude enzyme was the best biocatalyst for enantiopure d-lysine production. The reaction temperature, pH, metal ion additive, and pyridoxal 5′-phosphate content of this two-step production process were subsequently optimized. Under optimal conditions, 750.7 mmol/L d-lysine was finally obtained from 1710 mmol/L l-lysine after 1 h of racemization reaction and 0.5 h of decarboxylation reaction. d-lysine yield could reach 48.8% with enantiomeric excess (ee ≥ 99%.

  18. Lysine-Rich Proteins in High-Lysine Hordeum Vulgare Grain

    DEFF Research Database (Denmark)

    Ingversen, J.; Køie, B.

    1973-01-01

    The salt-soluble proteins in barley grain selected for high-lysine content (Hiproly, CI 7115 and the mutants 29 and 86) and of a control (Carlsberg II) with normal lysine content, contain identical major proteins as determined by MW and electrophoretic mobility. The concentration of a protein gro...

  19. Global profiling of lysine reactivity and ligandability in the human proteome

    Science.gov (United States)

    Hacker, Stephan M.; Backus, Keriann M.; Lazear, Michael R.; Forli, Stefano; Correia, Bruno E.; Cravatt, Benjamin F.

    2017-12-01

    Nucleophilic amino acids make important contributions to protein function, including performing key roles in catalysis and serving as sites for post-translational modification. Electrophilic groups that target amino-acid nucleophiles have been used to create covalent ligands and drugs, but have, so far, been mainly limited to cysteine and serine. Here, we report a chemical proteomic platform for the global and quantitative analysis of lysine residues in native biological systems. We have quantified, in total, more than 9,000 lysines in human cell proteomes and have identified several hundred residues with heightened reactivity that are enriched at protein functional sites and can frequently be targeted by electrophilic small molecules. We have also discovered lysine-reactive fragment electrophiles that inhibit enzymes by active site and allosteric mechanisms, as well as disrupt protein-protein interactions in transcriptional regulatory complexes, emphasizing the broad potential and diverse functional consequences of liganding lysine residues throughout the human proteome.

  20. Global profiling of lysine reactivity and ligandability in the human proteome.

    Science.gov (United States)

    Hacker, Stephan M; Backus, Keriann M; Lazear, Michael R; Forli, Stefano; Correia, Bruno E; Cravatt, Benjamin F

    2017-12-01

    Nucleophilic amino acids make important contributions to protein function, including performing key roles in catalysis and serving as sites for post-translational modification. Electrophilic groups that target amino-acid nucleophiles have been used to create covalent ligands and drugs, but have, so far, been mainly limited to cysteine and serine. Here, we report a chemical proteomic platform for the global and quantitative analysis of lysine residues in native biological systems. We have quantified, in total, more than 9,000 lysines in human cell proteomes and have identified several hundred residues with heightened reactivity that are enriched at protein functional sites and can frequently be targeted by electrophilic small molecules. We have also discovered lysine-reactive fragment electrophiles that inhibit enzymes by active site and allosteric mechanisms, as well as disrupt protein-protein interactions in transcriptional regulatory complexes, emphasizing the broad potential and diverse functional consequences of liganding lysine residues throughout the human proteome.

  1. Effects of lysine clonixinate and ketorolac tromethamine on prostanoid release from various rat organs incubated ex vivo.

    Science.gov (United States)

    Pallapies, D; Salinger, A; Meyer zum Gottesberge, A; Atkins, D J; Rohleder, G; Nagyiványi, P; Peskar, B A

    1995-01-01

    The release of prostanoids from rat brain, gastric mucosa, lungs and kidneys incubated ex vivo has been investigated for up to 5 h after oral administration of 10 mg/kg lysine clonixinate or 1 mg/kg ketorolac tromethamine. Additionally, 60 min after drug administration, a time point of near-maximal inhibition of prostanoid release, the effects of 2.5, 10 and 30 mg/kg lysine clonixinate and of 0.0225, 0.15 and 1 mg/kg ketorolac tromethamine were compared. In all organs investigated both drugs inhibited fatty acid cyclooxygenase (COX) in a dose-dependent manner, but ketorolac tromethamine was more potent and had a longer-lasting effect than lysine clonixinate. While the ID50 values for lysine clonixinate were in the same order of magnitude for all 4 organs investigated, ketorolac tromethamine exhibited some organ selectivity with a particularly high activity in the kidneys. This effect might be related to the renal toxicity of ketorolac tromethamine. On the other hand, the difference in potency was smallest in brain suggesting that inhibition of central prostanoid biosynthesis could contribute to the rapid and effective inhibition of pain by both drugs. IC50 values for inhibition of purified COX-1 and COX-2 in vitro were slightly lower for lysine clonixinate (2.4 and 24.6 micrograms/ml, respectively) than for ketorolac tromethamine (3.7 and 25.6 micrograms/ml, respectively).

  2. Effect of sulfur analogue of lysine on bacterial protein biosynthesis

    International Nuclear Information System (INIS)

    Tanaka, Hidehiko; Soda, Kenji.

    1976-01-01

    S-(beta-Aminoethyl)-L-cysteine, a sulfur analogue of lysine inhibited strongly growth of Escherichia coli A-19, and weakly that of Corynebacterium sp. isolated from soil, but did not inhibit growth of Aerobacter aerogenes. In Corynebacterium sp. the inhibitory effect was markedly enhanced in the presence of L-threonine. The inhibition of growth by S-(beta-aminoethyl)-L-cysteine was rapidly reversed by the addition of L-lysine. S-(beta-Aminoethyl)-L-cysteine inhibited protein synthesis and the activity of lysyl-tRNA synthetase from E. coli and A. aerogenes. All the other lysine analogues tested inhibited the activity of enzyme, but S-(beta-aminoethyl)-L-cysteine derivatives, S-(beta-N-acetyl-aminoethyl)-L-cysteine and S-(beta-aminoethyl)-alpha-N-acetyl-L-cysteine were not effective. (auth.)

  3. A Proteomic Approach to Analyze the Aspirin-mediated Lysine Acetylome*

    Science.gov (United States)

    Tatham, Michael H.; Cole, Christian; Scullion, Paul; Wilkie, Ross; Westwood, Nicholas J.; Stark, Lesley A.; Hay, Ronald T.

    2017-01-01

    Aspirin, or acetylsalicylic acid is widely used to control pain, inflammation and fever. Important to this function is its ability to irreversibly acetylate cyclooxygenases at active site serines. Aspirin has the potential to acetylate other amino acid side-chains, leading to the possibility that aspirin-mediated lysine acetylation could explain some of its as-yet unexplained drug actions or side-effects. Using isotopically labeled aspirin-d3, in combination with acetylated lysine purification and LC-MS/MS, we identified over 12000 sites of lysine acetylation from cultured human cells. Although aspirin amplifies endogenous acetylation signals at the majority of detectable endogenous sites, cells tolerate aspirin mediated acetylation very well unless cellular deacetylases are inhibited. Although most endogenous acetylations are amplified by orders of magnitude, lysine acetylation site occupancies remain very low even after high doses of aspirin. This work shows that while aspirin has enormous potential to alter protein function, in the majority of cases aspirin-mediated acetylations do not accumulate to levels likely to elicit biological effects. These findings are consistent with an emerging model for cellular acetylation whereby stoichiometry correlates with biological relevance, and deacetylases act to minimize the biological consequences of nonspecific chemical acetylations. PMID:27913581

  4. Quantification of Nε-(2-Furoylmethyl)-L-lysine (furosine), Nε-(Carboxymethyl)-L-lysine (CML), Nε-(Carboxyethyl)-L-lysine (CEL) and total lysine through stable isotope dilution assay and tandem mass spectrometry.

    Science.gov (United States)

    Troise, Antonio Dario; Fiore, Alberto; Wiltafsky, Markus; Fogliano, Vincenzo

    2015-12-01

    The control of Maillard reaction (MR) is a key point to ensure processed foods quality. Due to the presence of a primary amino group on its side chain, lysine is particularly prone to chemical modifications with the formation of Amadori products (AP), Nε-(Carboxymethyl)-L-lysine (CML), Nε-(Carboxyethyl)-L-lysine (CEL). A new analytical strategy was proposed which allowed to simultaneously quantify lysine, CML, CEL and the Nε-(2-Furoylmethyl)-L-lysine (furosine), the indirect marker of AP. The procedure is based on stable isotope dilution assay followed by liquid chromatography tandem mass spectrometry. It showed high sensitivity and good reproducibility and repeatability in different foods. The limit of detection and the RSD% were lower than 5 ppb and below 8%, respectively. Results obtained with the new procedure not only improved the knowledge about the reliability of thermal treatment markers, but also defined new insights in the relationship between Maillard reaction products and their precursors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Tranexamic acid-induced fixed drug eruption

    Directory of Open Access Journals (Sweden)

    Natsuko Matsumura

    2015-01-01

    Full Text Available A 33-year-old male showed multiple pigmented patches on his trunk and extremities after he took tranexamic acid for common cold. He stated that similar eruptions appeared when he was treated with tranexamic acid for influenza 10 months before. Patch test showed positive results at 48 h and 72 h by 1% and 10% tranexamic acid at the lesional skin only. To our knowledge, nine cases of fixed drug eruption induced by tranexamic acid have been reported in Japan. Tranexamic acid is a safe drug and frequently used because of its anti-fibrinolytic and anti-inflammatory effects, but caution of inducing fixed drug eruption should be necessary.

  6. Site-specific effects of the nonsteroidal anti-inflammatory drug lysine clonixinate on rat brain opioid receptors.

    Science.gov (United States)

    Ortí, E; Coirini, H; Pico, J C

    1999-04-01

    In addition to effects in the periphery through inhibition of prostaglandin synthesis, several lines of evidence suggest that nonsteroidal anti-inflammatory drugs (NSAIDs) act in the central nervous system. The possibility that the central action of NSAIDs involves regulation of opioid receptors was investigated by quantitative autoradiography of mu, delta, and kappa sites in rat brain slices. Increased (p lysine clonixinate. Labeling of delta receptors was lower in the lateral septum, and kappa sites decreased in thalamic nuclei. These effects were not mediated through direct interaction with opioid-binding sites, since receptor-binding assays using rat brain membranes confirmed that clonixinate up to 1 x 10(-4) mol/l does not inhibit mu, delta, and kappa receptor specific binding. Central effects of NSAIDs might, therefore, involve interaction with the opioid receptor system through indirect mechanisms.

  7. A Proteomic Approach to Analyze the Aspirin-mediated Lysine Acetylome.

    Science.gov (United States)

    Tatham, Michael H; Cole, Christian; Scullion, Paul; Wilkie, Ross; Westwood, Nicholas J; Stark, Lesley A; Hay, Ronald T

    2017-02-01

    Aspirin, or acetylsalicylic acid is widely used to control pain, inflammation and fever. Important to this function is its ability to irreversibly acetylate cyclooxygenases at active site serines. Aspirin has the potential to acetylate other amino acid side-chains, leading to the possibility that aspirin-mediated lysine acetylation could explain some of its as-yet unexplained drug actions or side-effects. Using isotopically labeled aspirin-d 3 , in combination with acetylated lysine purification and LC-MS/MS, we identified over 12000 sites of lysine acetylation from cultured human cells. Although aspirin amplifies endogenous acetylation signals at the majority of detectable endogenous sites, cells tolerate aspirin mediated acetylation very well unless cellular deacetylases are inhibited. Although most endogenous acetylations are amplified by orders of magnitude, lysine acetylation site occupancies remain very low even after high doses of aspirin. This work shows that while aspirin has enormous potential to alter protein function, in the majority of cases aspirin-mediated acetylations do not accumulate to levels likely to elicit biological effects. These findings are consistent with an emerging model for cellular acetylation whereby stoichiometry correlates with biological relevance, and deacetylases act to minimize the biological consequences of nonspecific chemical acetylations. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  8. Molecular and structural insight into lysine selection on substrate and ubiquitin lysine 48 by the ubiquitin-conjugating enzyme Cdc34

    DEFF Research Database (Denmark)

    Suryadinata, Randy; Holien, Jessica K; Yang, George

    2013-01-01

    , the mechanisms of lysine selection are not clearly understood. The positioning of lysine(s) toward the E2/E3 active site and residues proximal to lysines are critical in their selection. We investigated determinants of lysine specificity of the ubiquitin-conjugating enzyme Cdc34, toward substrate and Ub lysines....... Evaluation of the relative importance of different residues positioned -2, -1, +1 and +2 toward ubiquitination of its substrate, Sic1, on lysine 50 showed that charged residues in the -1 and -2 positions negatively impact on ubiquitination. Modeling suggests that charged residues at these positions alter...... the native salt-bridge interactions in Ub and Cdc34, resulting in misplacement of Sic1 lysine 50 in the Cdc34 catalytic cleft. During polyubiquitination, Cdc34 showed a strong preference for Ub lysine 48 (K48), with lower activity towards lysine 11 (K11) and lysine 63 (K63). Mutating the -2, -1, +1 and +2...

  9. Lysine purification with cation exchange resin

    International Nuclear Information System (INIS)

    Khayati, GH.; Mottaghi Talab, M.; Hamooni Hagheeghat, M.; Fatemi, M.

    2003-01-01

    L-lysine is an essential amino acid for the growth most of animal species and the number one limiting amino acid for poultry. After production and biomass removal by filtration and centrifugation, the essential next step is the lysine purification and recovery. There are different methods for lysine purification. The ion exchange process is one of the most commonly used purification methods. Lysine recovery was done from broth by ion exchange resin in three different ways: repeated passing, resin soaking and the usual method. Impurities were isolated from the column by repeated wash with distilled water. Recovery and purification was done with NH 4 OH and different alcohol volumes respectively. The results showed that repeated passing is the best method for lysine absorption (maximum range 86.21 %). Washing with alkali solution revealed that most of lysine is obtained in the first step of washing. The highest degree of lysine purification was achieved with the use of 4 volumes of alcohol

  10. Effects of single oral doses of lysine clonixinate and acetylsalicylic acid on platelet functions in man.

    Science.gov (United States)

    Pallapies, D; Muhs, A; Bertram, L; Rohleder, G; Nagyiványi, P; Peskar, B A

    1996-01-01

    Lysine clonixinate is an analgesic drug with a so far unknown mechanism of action. We have determined its effect on platelet cyclooxygenase in man. Biosynthesis of thromboxane (TX)B2 and prostaglandin (PG)F2 alpha in clotting whole blood ex vivo as well as collagen-induced platelet aggregation measured before and at various time points after oral administration of 125 mg lysine clonixinate were compared to results obtained with 500 mg acetylsalicylic acid (ASA). While biosynthesis of both TXB2 and PGF2 alpha measured radioimmunologically was inhibited significantly 2.5 h, but not 6 h, after administration of lysine clonixinate, inhibition by ASA was much greater and still highly significant after 48 h. Similarly, collagen-induced aggregation of platelet-rich plasma was inhibited for a longer period and to a greater extent after administration of ASA than after lysine clonixinate. Our results indicate that lysine clonixinate is a cyclooxygenase inhibitor of moderate potency. It remains to be investigated whether mechanisms other than inhibition of cyclooxygenase contribute to the analgesic activity of lysine clonixinate.

  11. Effect of lysine clonixinate on the pharmacokinetics and anticoagulant activity of phenprocoumon.

    Science.gov (United States)

    Russmann, S; Dilger, K; Trenk, D; Nagyivanyi, P; Jähnchen, E

    2001-11-01

    The effect of the non-steroidal anti-inflammatory drug lysine clonixinate ([2-(3-chloro-o-toluidino)nicotinic acid]-L-lysinate, CAS 55837-30-4) on the pharmacokinetics and anticoagulant activity of phenprocoumon (4-hydroxy-3-(1-phenylpropyl)-coumarin, CAS 435-97-2) was investigated in an open, randomised, two-fold, cross-over study in 12 healthy male volunteers. These subjects received a single dose of 18 mg phenprocoumon without or with concomitant treatment with lysine clonixinate (125 mg five times a day for 3 days before and 13 days after ingestion of a single dose of phenprocoumon). Pharmacokinetic parameters of phenprocoumon following oral administration were: CL/f: 0.779 +/- 0.157 ml/min, half-life of elimination: 147.2 +/- 19.9 h; free fraction in serum: 0.51 +/- 0.20%. These parameters were not significantly altered by concomitant treatment with lysine clonixinate. Prothrombin time increased from 13.3 +/- 1.3 s (at time 0) to 17.7 +/- 2.7 s following phenprocoumon and from 13.3 +/- 1.2 s to 18.0 +/- 2.2 s following combined administration. Prothrombin time returned to the pretreatment values 240 h after administration of phenprocoumon. The integrated effect (AUEC0-288 h) was identical following both treatments (4.303 +/- 461 and 4.303 +/- 312 s x h for phenprocoumon alone and phenprocoumon with lysine clonixinate, respectively). Thus, lysine clonixinate administered in therapeutic doses does not affect the pharmacokinetics and anticoagulant activity of phenproxoumon.

  12. Catabolism of lysine by mixed rumen bacteria

    International Nuclear Information System (INIS)

    Onodera, Ryoji; Kandatsu, Makoto.

    1975-01-01

    Metabolites arising from the catabolism of lysine by the mixed rumen bacteria were chromatographically examined by using radioactive lysine. After 6 hr incubation, 241 nmole/ml of lysine was decomposed to give ether-soluble substances and CO 2 by the bacteria and 90 nmole/ml of lysine was incorporated unchanged into the bacteria. delta-Aminovalerate, cadaverine or pipecolate did not seem to be produced from lysine even after incubation of the bacteria with addition of those three amino compounds to trap besides lysine and radioactive lysine. Most of the ether-soluble substances produced from radioactive lysine was volatile fatty acids (VFAs). Fractionation of VFAs revealed that the peaks of butyric and acetic acids coincided with the strong radioactive peaks. Small amounts of radioactivities were detected in propionic acid peak and a peak assumed to be caproic acid. The rumen bacteria appeared to decompose much larger amounts of lysine than the rumen ciliate protozoa did. (auth.)

  13. Anti-fibrinolytic and anti-microbial activities of a serine protease inhibitor from honeybee (Apis cerana) venom.

    Science.gov (United States)

    Yang, Jie; Lee, Kwang Sik; Kim, Bo Yeon; Choi, Yong Soo; Yoon, Hyung Joo; Jia, Jingming; Jin, Byung Rae

    2017-10-01

    Bee venom contains a variety of peptide constituents, including low-molecular-weight protease inhibitors. While the putative low-molecular-weight serine protease inhibitor Api m 6 containing a trypsin inhibitor-like cysteine-rich domain was identified from honeybee (Apis mellifera) venom, no anti-fibrinolytic or anti-microbial roles for this inhibitor have been elucidated. In this study, we identified an Asiatic honeybee (A. cerana) venom serine protease inhibitor (AcVSPI) that was shown to act as a microbial serine protease inhibitor and plasmin inhibitor. AcVSPI was found to consist of a trypsin inhibitor-like domain that displays ten cysteine residues. Interestingly, the AcVSPI peptide sequence exhibited high similarity to the putative low-molecular-weight serine protease inhibitor Api m 6, which suggests that AcVSPI is an allergen Api m 6-like peptide. Recombinant AcVSPI was expressed in baculovirus-infected insect cells, and it demonstrated inhibitory activity against trypsin, but not chymotrypsin. Additionally, AcVSPI has inhibitory effects against plasmin and microbial serine proteases; however, it does not have any detectable inhibitory effects on thrombin or elastase. Consistent with these inhibitory effects, AcVSPI inhibited the plasmin-mediated degradation of fibrin to fibrin degradation products. AcVSPI also bound to bacterial and fungal surfaces and exhibited anti-microbial activity against fungi as well as gram-positive and gram-negative bacteria. These findings demonstrate the anti-fibrinolytic and anti-microbial roles of AcVSPI as a serine protease inhibitor. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. [Intravenous lysine clonixinate for the treatment of migraine: an open pilot study].

    Science.gov (United States)

    Krymchantowski, A V; Barbosa, J

    1999-09-01

    Several oral nonsteroidal anti-inflammatory drugs (NSAID) are effective to treat migraine attacks. Despite its efficacy to treat migraine and other pain, there are a few commercial NSAIDs available for intravenous (i.v.) administration. Lysine clonixinate (LC) is a NSAID derived from nicotinic acid that has been proven effective in various algic syndromes such as renal colic, nerve compression, muscular pain and odontalgias. The aim of this study was to evaluate the efficacy of the i.v. LC in the treatment of severe attacks of migraine. We studied prospectively 19 patients, 17 women and 2 men, ages from 18 to 57 years, with the diagnosis of migraine according to the International Headache Society criteria. The patients were oriented to proceed to the clinic once the headache has started, and were placed under an i.v. infusion of LC and saline in a superficial vein of the forearm, once the intensity reached severe. Evaluating the headache intensity after 30, 60 and 90 minutes, as well as the presence of side effects, we observed that all of the 19 patients were headache free after 90 minutes. Some patients presented mild adverse effects and the vital signs were not significantly affected. We then concluded that the i.v. infusion of the NSAID LC (2-3-chloro-o-toluidin)piridin-3-lysine carboxilate), a derived from the nicotinic acid with a chemical structure that resembles the flufenamic acid, was efficient abolishing a severe migraine attack after 90 minutes in 19 patients. Controlled studies with a double-blind and randomized design, and treating a greater number of patients and attacks are necessary to confirm these initial observations.

  15. Quantification of Nε-(2-Furoylmethyl)-L-lysine (furosine), Nε-(Carboxymethyl)-L-lysine (CML), Nε-(Carboxyethyl)-L-lysine (CEL) and total lysine through stable isotope dilution assay and tandem mass spectrometry

    NARCIS (Netherlands)

    Troise, A.D.; Fiore, A.; Wiltafsky, M.; Fogliano, V.

    2015-01-01

    The control of Maillard reaction (MR) is a key point to ensure processed foods quality. Due to the presence of a primary amino group on its side chain, lysine is particularly prone to chemical modifications with the formation of Amadori products (AP), Nε-(Carboxymethyl)-L-lysine (CML),

  16. [Effects of lysine clonixinate on platelet function. Comparison with other non-steroidal anti-inflammatory agents].

    Science.gov (United States)

    Kramer, E H; Sassetti, B; Kaminker, A J; De Los Santos, A R; Martí, M L; Di Girolamo, G

    2001-01-01

    One of the mechanisms of action of non steroid antiinflammatory drugs (NSAIDs) consists of inhibition of prostaglandin synthesis. This explains many of the pharmacological effects and adverse events observed in medical practice. Administration of NSAIDs to patients with hemostatic disorders or perioperative conditions entails the risk of bleeding due to inhibition of platelet function. This study deals with platelet changes induced by lysine clonixinate vs diclofenac, ibuprofen and aspirin in classical tests such as platelet count, platelet factor 3 (PF3) activity and platelet aggregation with various inductors and more recent procedures such as P-selectin measurement by flow cytometry. Unlike control drugs, lysine clonixinate did not induce changes in platelet count or function when administered to healthy volunteers at the commonly used therapeutic doses.

  17. Novel α-Oxoamide Advanced-Glycation Endproducts within the N6-Carboxymethyl Lysine and N6-Carboxyethyl Lysine Reaction Cascades.

    Science.gov (United States)

    Baldensperger, Tim; Jost, Tobias; Zipprich, Alexander; Glomb, Marcus A

    2018-02-28

    The highly reactive α-dicarbonyl compounds glyoxal and methylglyoxal are major precursors of posttranslational protein modifications in vivo. Model incubations of N 2 -t-Boc-lysine and either glyoxal or methylglyoxal were used to further elucidate the underlying mechanisms of the N 6 -carboxymethyl lysine and N 6 -carboxyethyl lysine reaction cascades. After independent synthesis of the authentic reference standards, we were able to detect N 6 -glyoxylyl lysine and N 6 -pyruvoyl lysine for the first time by HPLC-MS 2 analyses. These two novel amide advanced-glycation endproducts were exclusively formed under aerated conditions, suggesting that they were potent markers for oxidative stress. Analogous to the well-known Strecker degradation pathway, leading from amino acids to Strecker acids, the oxidation of an enaminol intermediate is suggested to be the key mechanistic step. A highly sensitive workup for the determination of AGEs in tissues was developed. In support of our hypothesis, the levels of N 6 -glyoxylyl lysine and N 6 -pyruvoyl lysine in rat livers indeed correlated with liver cirrhosis and aging.

  18. Reactive lysine content in commercially available pet foods

    NARCIS (Netherlands)

    Rooijen, van C.; Bosch, G.; Poel, van der A.F.B.; Wierenga, P.A.; Alexander, L.; Hendriks, W.H.

    2014-01-01

    The Maillard reaction can occur during processing of pet foods. During this reaction, the e-amino group of lysine reacts with reducing sugars to become unavailable for metabolism. The aim of the present study was to determine the reactive lysine (RL; the remaining available lysine) to total lysine

  19. Digestible lysine levels in diets supplemented with ractopamine

    Directory of Open Access Journals (Sweden)

    Evelar de Oliveira Souza

    2011-10-01

    Full Text Available In order evaluate digestible lysine levels in diets supplemented with 20 ppm of ractopamine on the performance and carcass traits, 64 barrows with high genetic potential at finishing phase were allotted in a completely randomized block design with four digestible lysine levels (0.80, 0.90, 1.00, and 1.10%, eight replicates and two pigs per experimental unit. Initial body weight and pigs' kinship were used as criteria in the blocks formation. Diets were mainly composed of corn and soybean meal supplemented with minerals, vitamins and amino acids to meet pigs' nutritional requirements at the finishing phase, except for digestible lysine. No effect of digestible lysine levels was observed in animal performance. The digestible lysine intake increased linearly by increasing the levels of digestible lysine in the diets. Carcass traits were not influenced by the dietary levels of digestible lysine. The level of 0.80% of digestible lysine in diets supplemented with 20 ppm ractopamine meets the nutritional requirements of castrated male pigs during the finishing phase.

  20. Increase of rutin antioxidant activity by generating Maillard reaction products with lysine.

    Science.gov (United States)

    Zhang, Ru; Zhang, Bian-Ling; He, Ting; Yi, Ting; Yang, Ji-Ping; He, Bin

    2016-06-01

    Rutin exists in medicinal herbs, fruits, vegetables, and a number of plant-derived sources. Dietary sources containing rutin are considered beneficial because of their potential protective roles in multiple diseases related to oxidative stresses. In the present study, the change and antioxidation activity of rutin in Maillard reaction with lysine through a heating process were investigated. There is release of glucose and rhamnose that interact with lysine to give Maillard reaction products (MRPs), while rutin is converted to less-polar quercetin and a small quantity of isoquercitrin. Because of their high cell-membrane permeability, the rutin-lysine MRPs increase the free radical-scavenging activity in HepG2 cells, showing cellular antioxidant activity against Cu(2+)-induced oxidative stress higher than that of rutin. Furthermore, the MRPs significantly increased the Cu/Zn SOD (superoxide dismutase) activity and Cu/Zn SOD gene expression of HepG2 cells, consequently enhancing antioxidation activity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. [Effect of the lysine guanidination on proteomic analysis].

    Science.gov (United States)

    Zheng, Hao; Mao, Jiawei; Pan, Yanbo; Liu, Zhongshan; Liu, Zheyi; Ye, Mingliang; Zou, Hanfa

    2014-04-01

    The guanidination of lysine side chain was paid great attention in recent years. It plays an important role in qualitative and quantitative proteomics. In this study, based on the results of separated peptides extracted from HeLa cells before and after the guanidination by liquid chromatography-tandem mass spectrometry (LC-MS/MS), the effect of the guanidination of three different kinds of peptides was systematically analyzed. It was found that the selectivity of the guanidination of the lysine side chain was as high as 96.8%. The ratio of identified peptides with lysine at C-term to all peptides increased from 51.7% to 57.3% and more new peptides were identified, while the ratio of peptides with lysine in the middle or without lysine changed little. Further study on the ratio of b and y ions indicated that there were more y ions of peptides with lysine at C-term after the guanidination. The results proved that the selective conversion of lysine to homoarginine by the guanidination could increase the sensitivity and selectivity of mass spectrum. The increased basicity and ability to sequester proton of lysine produced more y ions fragmentation information, which contributed to more identified peptides. It concluded that the lysine guanidination can improve the coverage of proteomic analysis.

  2. Topological dispositions of lysine α380 and lysine γ486 in the acetylcholine receptor from Torpedo californica

    International Nuclear Information System (INIS)

    Dwyer, B.P.

    1991-01-01

    The locations have been determined, with respect to the plasma membrane, of lysine α380 and lysine γ486 in the α subunit and the γ subunit, respectively, of the nicotinic acetylcholine receptor from Torpedo californica. Immunoadsorbents were constructed that recognize the carboxy terminus of the peptide GVKYIAE released by proteolytic digestion from positions 378-384 in the amino acid sequence of the α subunit of the acetylcholine receptor and the carboxy terminus of the peptide KYVP released by proteolytic digestion from positions 486-489 in the amino acid sequence of the γ subunit. They were used to isolate these peptides from proteolytic digests of polypeptides from the acetylcholine receptor. Sealed vesicles containing the native acetylcholine receptor were labeled with pyridoxal phosphate and sodium [ 3 H]-borohydride. The effect of saponin on the incorporation of pyridoxamine phosphate into lysine α380 and lysine γ486 from the acetylcholine receptor in these vesicles was assessed with the immunoadsorbents. The conclusions that follow from these results are that lysine α380 is on the inside surface of a vesicle and lysine γ486 is on the outside surface. Because a majority (85%) of the total binding sites for α-bungarotoxin bind the toxin in the absence of saponin, the majority of the vesicles are right side out with the inside of the vesicle corresponding to the cytoplasmic surface and the outside of the vesicle corresponding to the extracytoplasmic, synaptic surface. Because lysine α380 and lysine γ486 lie on opposite sides of the membrane, a membrane-spanning segment must be located between the two positions occupied by these two amino acids in the common sequence of a polypeptide of the acetylcholine receptor

  3. Role of L-lysine-alpha-ketoglutarate aminotransferase in catabolism of lysine as a nitrogen source for Rhodotorula glutinis.

    Science.gov (United States)

    Kinzel, J J; Winston, M K; Bhattacharjee, J K

    1983-01-01

    Wild-type and saccharopine dehydrogenaseless mutant strains of Rhodotorula glutinis grew in minimal medium containing lysine as the sole nitrogen source and simultaneously accumulated, in the culture supernatant, large amounts of a product identified as alpha-aminoadipic-delta-semialdehyde. The saccharopine dehydrogenase and pipecolic acid oxidase levels remained unchanged in wild-type cells grown in the presence of ammonium or lysine as the nitrogen source. Lysine-alpha-ketoglutarate aminotransferase activity was demonstrated in ammonium-grown cells. This activity was depressed in cells grown in the presence of lysine as the sole source of nitrogen. PMID:6408065

  4. Controllable synthesis of functional nanocomposites: Covalently functionalize graphene sheets with biocompatible L-lysine

    International Nuclear Information System (INIS)

    Mo, Zunli; Gou, Hao; He, Jingxian; Yang, Peipei; Feng, Chao; Guo, Ruibin

    2012-01-01

    Highlights: ► The biocompatible L-lysine functionalized graphene sheets (Gs/Lys) were synthesized controllably using a novel method. ► The Gs/Lys nanocomposites are water-soluble, biocompatible and chiral. ► A chiral graphene derivative was proposed. - Abstract: In this paper a novel method to synthesize functionalize graphene sheets (Gs) by biocompatible L-lysine (Gs/Lys) is reported. The method was composed of two steps: (1) we controllably synthesized self-assembly Gs/Lys-Cu-Lys through the terminal amino of copper L-lysine (Lys-Cu-Lys) attaching to graphite oxide (GO) and then reducing. (2) Obtained the Gs/Lys by eliminating the copper ion. This method could also be used to functionalize other nanomaterials by L-lysine. The Gs/Lys nanocomposites are water-soluble, biocompatible, and above all, it is a chiral material of graphene, which is proposed by us. This novel material will be promising for more applications of graphene. The formation of Gs/Lys nanocomposites were confirmed by scanning electron microscopy (SEM), Fourier-transform infrared spectra (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermal gravimetric (TG) analysis.

  5. Ascidian Sperm Lysin System

    OpenAIRE

    Hitoshi, Sawada; Department of Biochemistry, Graduate School of Pharmaceutical Sciences, Hokkaido University

    2002-01-01

    Fertilization is a precisely controlled process involving many gamete molecules in sperm binding to and penetration through the extracellular matrix of the egg. After sperm bind to the extracellular matrix (vitelline coat), they undergo the acrosome reaction which exposes and partially releases a lytic agent called "lysin" to digest the vitelline coat for the sperm penetration. The vitelline coat sperm lysin is generally a protease in deuterostomes. The molecular mechanism of the actual degra...

  6. Lysine: Participation in life, production and biosynthesis

    International Nuclear Information System (INIS)

    Shah, A.H.; Hameed, A.

    2002-01-01

    Lysine plays a vital role in life. Its demands increase worldwide. It is in the interest of students to advertise the supreme importance of its productions. In this report, the mechanism and the biosynthetic pathway of lysine in corynebacterium glutamicum is illustrated, in a simple and ready understandable way. These will pave the way of lysine production. (author)

  7. Global Analysis of Protein Lysine Succinylation Profiles and Their Overlap with Lysine Acetylation in the Marine Bacterium Vibrio parahemolyticus.

    Science.gov (United States)

    Pan, Jianyi; Chen, Ran; Li, Chuchu; Li, Weiyan; Ye, Zhicang

    2015-10-02

    Protein lysine acylation, including acetylation and succinylation, has been found to be a major post-translational modification (PTM) and is associated with the regulation of cellular processes that are widespread in bacteria. Vibrio parahemolyticus is a model marine bacterium that causes seafood-borne illness in humans worldwide. The lysine acetylation of V. parahemolyticus has been extensively characterized in our previous work, and here, we report the first global analysis of lysine succinylation and the overlap between the two types of acylation in this bacterium. Using high-accuracy nano liquid chromatography-tandem mass spectrometry combined with affinity purification, we identified 1931 lysine succinylated peptides matched on 642 proteins, with the quantity of the succinyl-proteins accounting for 13.3% of the total proteins in cells. Bioinformatics analysis results showed that these succinylated proteins are involved in almost every cellular process, particularly in protein biosynthesis and metabolism, and are distributed in diverse subcellular compartments. Moreover, several sequence motifs were identified, including succinyl-lysine flanked by a lysine or arginine residue at the -8, -7, or +7 position and without these residues at the -1 or +2 position, and these motifs differ from those found in other bacteria and eukaryotic cells. Furthermore, a total of 517 succinyl-lysine sites (26.7%) on 288 proteins (44.9%) were also found to be acetylated, suggesting extensive overlap between succinylation and acetylation in this bacterium. This systematic analysis provides a promising starting point for further investigations of the physiologic and pathogenic roles of lysine succinylation and acetylation in V. parahemolyticus.

  8. Optimization of lysine metabolism in Corynebacterium glutamicum

    DEFF Research Database (Denmark)

    Rytter, Jakob Vang

    ,000,000 tons. The aim of this project is to optimize the yield of lysine in C. glutamicum using metabolic engineering strategies. According to a genome scale model of C. glutamicum, theoretically there is much room for increasing the lysine yield (Kjeldsen and Nielsen 2009). Lysine synthesis requires NADPH......Commercial pig and poultry production use the essential amino acid lysine as a feed additive with the purpose of optimizing the feed utilization. Lysine is produced by a fermentation process involving either Corynebacterium glutamicum or Escherichia coli. The global annual production is around 1...... the project intends to eliminate. PGI catalyzes the conversion of alpha-D-glucose-6-phosphate to fructose-6-phosphate just downstream of the branch in the glycolysis, but it also catalyzes the reverse reaction. It is unknown whether up- or down-regulation of the pgi is required to increase the flux through...

  9. Lysine conjugation properties in human IgGs studied by integrating high-resolution native mass spectrometry and bottom-up proteomics

    NARCIS (Netherlands)

    Gautier, Violette|info:eu-repo/dai/nl/372660851; Boumeester, Anja J.; Lössl, Philip|info:eu-repo/dai/nl/371559693; Heck, Albert J R|info:eu-repo/dai/nl/105189332

    2015-01-01

    Antibody-drug conjugates (ADCs) are a novel class of biopharmaceuticals several of which are now being investigated in clinical studies. In ADCs, potent cytotoxic drugs are coupled via a linker to reactive residues in IgG monoclonal antibodies. Linkage to lysine residues in the IgGs, using

  10. Substrates for Efficient Fluorometric Screening Employing the NAD-Dependent Sirtuin 5 Lysine Deacylase (KDAC) Enzyme

    DEFF Research Database (Denmark)

    Madsen, Andreas Stahl; Olsen, Christian Adam

    2012-01-01

    The class III lysine deacylases (KDACs), also known as the sirtuins, have emerged as interesting drug targets for therapeutic intervention in a variety of diseases. To gain a deeper understanding of the processes affected by sirtuins, the development of selective small molecule modulators of indi...

  11. Protection against inflammatory β-cell damage by lysine deacetylase inhibition and microRNA expression?

    DEFF Research Database (Denmark)

    Vestergaard, Anna Lindeløv; Pallesen, Emil Marek Heymans; Novotny, Guy Wayne

    Background and aims: Pro-inflammatory cytokines contribute to pancreatic β-cell apoptosis in type 1 and 2 diabetes mellitus. The detrimental effects resulting from cytokine-induced signaling in the β cell can be reduced by inhibition of class I classical lysine deacetylases (KDACi), especially HDAC...... of oxidative stress proteins responsible for β-cell death. The aim of the study is to identify novel and specific therapeutic targets for β-cell protection by mapping the miR profile of β cells rescued from inflammatory assault by inhibition of lysine deacetylation, thereby identifying miR that repress....... The perspective of this study is to develop novel anti-diabetic drugs targeting HDAC1 and/or associated miR....

  12. Biotinylation of lysine method identifies acetylated histone H3 lysine 79 in Saccharomyces cerevisiae as a substrate for Sir2.

    Science.gov (United States)

    Bheda, Poonam; Swatkoski, Stephen; Fiedler, Katherine L; Boeke, Jef D; Cotter, Robert J; Wolberger, Cynthia

    2012-04-17

    Although the biological roles of many members of the sirtuin family of lysine deacetylases have been well characterized, a broader understanding of their role in biology is limited by the challenges in identifying new substrates. We present here an in vitro method that combines biotinylation and mass spectrometry (MS) to identify substrates deacetylated by sirtuins. The method permits labeling of deacetylated residues with amine-reactive biotin on the ε-nitrogen of lysine. The biotin can be utilized to purify the substrate and identify the deacetylated lysine by MS. The biotinyl-lysine method was used to compare deacetylation of chemically acetylated histones by the yeast sirtuins, Sir2 and Hst2. Intriguingly, Sir2 preferentially deacetylates histone H3 lysine 79 as compared to Hst2. Although acetylation of K79 was not previously reported in Saccharomyces cerevisiae, we demonstrate that a minor population of this residue is indeed acetylated in vivo and show that Sir2, and not Hst2, regulates the acetylation state of H3 lysine 79. The in vitro biotinyl-lysine method combined with chemical acetylation made it possible to identify this previously unknown, low-abundance histone acetyl modification in vivo. This method has further potential to identify novel sirtuin deacetylation substrates in whole cell extracts, enabling large-scale screens for new deacetylase substrates.

  13. Strain differences in the response to morphine on incorporation of 3H-lysine into rat brain protein

    International Nuclear Information System (INIS)

    Ford, D.H.; Rhines, R.K.; Levi, M.A.

    1977-01-01

    The effect of morphine on the specific activity (SA) of lysine in the plasma free amino acid (FFA) fraction and in the cerebral cortical FAA and protein fractions, as well as on the specific accumulation and incorporation, was determined in male Sprague-Dawley and Wistar rats at various time intervals after intravenous injection of drug and amino acid into unanesthetized animals. The lysine SA was higher in Sprague-Dawley than in Wistar rats in the plasma and brain FAA fraction and in the protein fraction. In the SD strain, morphine decreased the SA of plasma FAA significantly, but had only slight effects in the Wistar strain. In the cortical gray matter, morphine elevated the SA of lysine significantly in both strains. SA of the lysine in cerebral cortical protein increased in both strains with time. When the data for the free amino acids were expressed in terms of specific accumulation, the observed rates were higher in the Sprague-Dawley animals and reached a point of maximal concentration, which was not observed in animals of the Wistar strain. Morphine elevated the levels of specific accumulation of lysine into the cortical free amino acid pool in both strains of rat. It is concluded that Sprague-Dawley and Wistar rats are not equivalent in relation to the accumulation of an amino acid in the brain FAA pool from the plasma and that the effect of morphine on specific incorporation of lysine into brain protein is greater in Wistar rats. (author)

  14. Biodistribution and catabolism of 18F-labelled isopeptide N(epsilon)-(gamma-glutamyl)-L-lysine.

    Science.gov (United States)

    Hultsch, C; Bergmann, R; Pawelke, B; Pietzsch, J; Wuest, F; Johannsen, B; Henle, T

    2005-12-01

    Isopeptide bonds between the epsilon-amino group of lysine and the gamma-carboxamide group of glutamine are formed during strong heating of pure proteins or, more important, by enzymatic reaction mediated by transglutaminases. Despite the wide use of a microbial transglutaminase in food biotechnology, up to now little is known about the metabolic fate of the isopeptide N(epsilon)-(gamma-glutamyl)-L-lysine. In the present study, N-succinimidyl-4-[(18)F]fluorobenzoate was used to modify N(epsilon)-(gamma-glutamyl)-L-lysine at each of its two alpha-amino groups, resulting in the 4-[(18)F]fluorobenzoylated derivatives, for which biodistribution, catabolism, and elimination were investigated in male Wistar rats. A significant different biochemical behavior of the two labelled isopeptides was observed in terms of in vitro stability, in vivo metabolism as well as biodistribution. The results suggest that the metabolic fate of isopeptides is likely to be dependent on how they are reabsorbed - free or peptide bound.

  15. Differential Modulation of Cellular Bioenergetics by Poly(L-lysine)s of Different Molecular Weights

    DEFF Research Database (Denmark)

    Hall, Arnaldur; Wu, Lin-Ping; Parhamifar, Ladan

    2015-01-01

    Poly(L-lysine)s (PLLs), and related derivatives, have received considerable attention as nonviral vectors. High molecular weight PLLs (H-PLLs) are superior transfectants compared with low Mw PLLs (L-PLLs), but suggested to be more cytotoxic. Through a pan-integrated metabolomic approach using Sea...

  16. Solution Thermodynamics of Lysine Clonixinate in Some Ethanol + Water Mixtures

    OpenAIRE

    Delgado, Daniel R.; Martínez, Fleming; Gutiérrez, Rahumir A.

    2012-01-01

    The solubility of lysine clonixinate (LysClon) in several ethanol + water mixtures was determined at 293.15 to 313.15 K. The thermodynamic functions, Gibbs energy, enthalpy, and entropy of solution and of mixing were obtained from these solubility data by using the van’t Hoff and Gibbs equations. In general this drug exhibit good solubility and the greatest value was obtained in the mixture 0.60 in mass fraction of ethanol. A non-linear enthalpy–entropy relationship was observed from ...

  17. Microbial synthesis of poly(epsilon-lysine) and its various applications.

    Science.gov (United States)

    Shih, Ing-Lung; Shen, Ming-Haw; Van, Yi-Tsong

    2006-06-01

    This review article deals with the microbial synthesis, physiochemical properties, and potential applications of poly-epsilon-lysine (epsilon-PL), which is a naturally occurring biomaterial that is water soluble, biodegradable, edible and non-toxic toward humans and the environment. The potential applications of epsilon-PL as food preservatives, emulsifying agent, dietary agent, biodegradable fibers, highly water absorbable hydrogels, drug carriers, anticancer agent enhancer, biochip coatings in the fields of food, medicine, agriculture and electronics are also discussed in this review.

  18. Analgesic efficacy of lysine clonixinate, paracetamol and dipyrone in lower third molar extraction: a randomized controlled trial.

    Science.gov (United States)

    Noronha, Vladimir-Reimar-Augusto-de Souza; Gurgel, Gladson-de Souza; Alves, Luiz-César-Fonseca; Noman-Ferreira, Luiz-Cláudio; Mendonça, Lisette-Lobato; Aguiar, Evandro-Guimarães de; Abdo, Evandro-Neves

    2009-08-01

    The purpose of this study is to compare the analgesic effect of lysine clonixinate, paracetamol and dipyrone after lower third molar extraction. The sample consisted of 90 individuals with clinical indication for inferior third molar extraction. The mean age of the sample was 22.3 years (DP +/-2.5). The individuals received the medication in unidentified bottles along with the intake instructions. The postoperative pain parameters were measured according to the Visual Analogical Scale (VAS) and the data was evaluated using the Kruskal-Wallis Test and Friedman Test, with the latter used to test different time intervals for each one of the drugs. The final sample consisted of 64 individuals, including 23 males (45.9%) and 41 females (64.1%) The mean age of the entire sample was 22.3 years (+/-2.5). The average length of the procedures was 33.9 minutes (+/-9.8). The distribution of mean values for this variable showed little variance for the different drugs (p=0.07). Lysine Clonixinate did not show any substantial impact on the postoperative pain control when compared to other drugs.

  19. PENILAIAN PENGARUH PENAMBAHAN LYSINE PADA NASI

    Directory of Open Access Journals (Sweden)

    Ignatius Tarwotjo

    2012-11-01

    Full Text Available Pengaruh penambahan lysine pada mutu protein nasi dilakukan pada tikus putih dengan mengukur Protein Efficiency Ratio. Nasi dan Nasi dengan sayur beserta laukpauk, seperti dikonsumsi oleh kebanyakan keluarga di Indonesia, yang berasnya lebih dulu ditambahi butiran premix berisi lysine, thiamine dan riboflavin ternaya menghasilkan Protein Efficiency Ratio lebih tinggi dari pada yang tidak ditambahi.

  20. Drug-to-antibody determination for an antibody-drug-conjugate utilizing cathepsin B digestion coupled with reversed-phase high-pressure liquid chromatography analysis.

    Science.gov (United States)

    Adamo, Michael; Sun, Guoyong; Qiu, Difei; Valente, Joseph; Lan, Wenkui; Song, Hangtian; Bolgar, Mark; Katiyar, Amit; Krishnamurthy, Girija

    2017-01-20

    Antibody drug conjugates or ADCs are currently being evaluated for their effectiveness as targeted chemotherapeutic agents across the pharmaceutical industry. Due to the complexity arising from the choice of antibody, drug and linker; analytical methods for release and stability testing are required to provide a detailed understanding of both the antibody and the drug during manufacturing and storage. The ADC analyzed in this work consists of a tubulysin drug analogue that is randomly conjugated to lysine residues in a human IgG1 antibody. The drug is attached to the lysine residue through a peptidic, hydrolytically stable, cathepsin B cleavable linker. The random lysine conjugation produces a heterogeneous mixture of conjugated species with a variable drug-to-antibody ratio (DAR), therefore, the average amount of drug attached to the antibody is a critical parameter that needs to be monitored. In this work we have developed a universal method for determining DAR in ADCs that employ a cathepsin B cleavable linker. The ADC is first cleaved at the hinge region and then mildly reduced prior to treatment with the cathepsin B enzyme to release the drug from the antibody fragments. This pre-treatment allows the cathepsin B enzyme unrestricted access to the cleavage sites and ensures optimal conditions for the cathepsin B to cleave all the drug from the ADC molecule. The cleaved drug is then separated from the protein components by reversed phase high performance liquid chromatography (RP-HPLC) and quantitated using UV absorbance. This method affords superior cleavage efficiency to other methods that only employ a cathepsin digestion step as confirmed by mass spectrometry analysis. This method was shown to be accurate and precise for the quantitation of the DAR for two different random lysine conjugated ADC molecules. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Molecular basis for endotoxin neutralization by amphipathic peptides derived from the alpha-helical cationic core-region of NK-lysin.

    Science.gov (United States)

    Brandenburg, Klaus; Garidel, Patrick; Fukuoka, Satoshi; Howe, Jörg; Koch, Michel H J; Gutsmann, Thomas; Andrä, Jörg

    2010-08-01

    An analysis of the interaction of the NK-lysin derived peptide NK-2 and of analogs thereof with bacterial lipopolysaccharide (LPS, endotoxin) was performed to determine the most important biophysical parameters for an effective LPS neutralization. We used microcalorimetry, FTIR spectroscopy, Zeta potential measurements, and small-angle X-ray scattering to analyze the peptide:LPS binding enthalpy, the accessible LPS surface charge, the fluidity of the LPS hydrocarbon chains, their phase transition enthalpy change, the aggregate structure of LPS, and how these parameters are modulated by the peptides. We conclude that (i) a high peptide:LPS binding affinity, which is facilitated by electrostatic and hydrophobic interactions and which leads to a positive Zeta potential, (ii) the formation of peptide-enriched domains, which destabilize the lipid packing, demonstrated by a drastic decrease of phase transition enthalpy change of LPS, and (iii) the multilamellarization of the LPS aggregate structure are crucial for an effective endotoxin neutralization by cationic peptides.

  2. Effect of vitamins and bivalent metals on lysine yield in Bacillus ...

    African Journals Online (AJOL)

    The effects of vitamins and bivalent metals on lysine accumulation in Bacillus strains were investigated. Biotin enhanced lysine production in all the Bacillus strains, while folic acid and riboflavin stimulated lysine yields in Bacillus megaterium SP 86 only. All bivalent metals stimulated lysine accumulation in B. megaterium ...

  3. Plant derived antioxidants and antifibrotic drugs: past, present and future

    Directory of Open Access Journals (Sweden)

    Devaraj Ezhilarasan

    2014-09-01

    Full Text Available Hepatic fibrosis occurs as a wound-healing process after several forms of chronic hepatic injury. Activation and proliferation of hepatic stellate cells play pivotal role in the pathogenesis of hepatic fibrosis. Many researchers, from the therapeutic perspective, have focused their attention on searching for novel agents with inhibitory effects on hepatic stellate cells proliferation and activation to prevent hepatic fibrogenesis and a number of plant derived antioxidants have been tested as anti-fibrogenic agents, they generally suppress proliferation and collagen synthesis. Plants remain an imperative source of novel drugs, novel drug leads and new chemical entities. The plant based drug discovery resulted primarily in the development of antioxidant, anti-cancer and other anti-infectious agents and continues to contribute to the new leads in clinical trials. This review summarizes some of those most important plant derived anti-fibrotic drugs and their beneficial effects on experimentally induced hepatic fibrosis in vitro and in vivo. The plant derived antioxidant compounds described herein are curcumin, silymarin, silibinin, baicalein, resveratrol, salvianolic acids, tetrandine, quercetin and berberine. Studies from ours and as demonstrated by pervious workers much information has been accumulated over the past two decades through in vivo and in vitro. In light of those studies, it has been confirmed that plants derived antioxidants, particularly flavanoids, show a significant influence to block hepatic fibrosis regardless of any etiology. This review outlines recent progress in the use of plant derived drugs against experimentally induced liver fibrosis by in vitro and in vivo studies and summarizes the possible mechanisms anti-fibrotic effects of these compounds.

  4. Desensitization to inhaled aztreonam lysine in an allergic patient with cystic fibrosis using a novel approach.

    Science.gov (United States)

    Guglani, Lokesh; Abdulhamid, Ibrahim; Ditouras, Joanna; Montejo, Jenny

    2012-10-01

    To report the successful desensitization of a highly allergic patient with cystic fibrosis (CF) to inhaled aztreonam lysine using the novel approach of intravenous desensitization followed by full-dose inhaled therapy without any adverse reactions. A 19-year-old woman with CF had persistent Pseudomonas aeruginosa-positive cultures and a history of type I hypersensitivity reactions to multiple medications, including aztreonam and tobramycin (intravenous and inhaled). To start therapy with an inhaled antipseudomonal antibiotic on a chronic basis, she underwent rapid desensitization to intravenous aztreonam followed by initiation of inhaled aztreonam lysine. Following intravenous desensitization with aztreonam, there was no adverse reaction or decline in lung function noted with inhaled aztreonam lysine and the chronic therapy was continued at home, with a modified regimen to maintain desensitization. Aztreonam lysine has been used for treatment of patients with CF with chronic P. aeruginosa colonization. Previous allergic reaction to intravenous aztreonam is considered a contraindication for use of aztreonam lysine. Our patient had a history of hives and facial swelling following administration of intravenous aztreonam (type I hypersensitivity reaction) as well as hypersensitivity to tobramycin. Rapid desensitization can be done for drugs that mediate a type I hypersensitivity reaction, with mast cells and basophils being the cellular targets. There are a few case reports of desensitization to inhaled antibiotics such as tobramycin and colistin, but desensitization to aztreonam lysine has not previously been reported. Desensitization of a patient with CF who is allergic to intravenous aztreonam was successfully accomplished with the novel approach of rapid intravenous desensitization followed by inhaled therapy. As inhaled antibiotics are being increasingly used for patients with CF, this novel strategy can be used for desensitizing allergic patients with CF to

  5. Lysine-functionalized nanodiamonds: synthesis, physiochemical characterization, and nucleic acid binding studies

    Directory of Open Access Journals (Sweden)

    Kaur R

    2012-07-01

    Full Text Available Randeep Kaur,1 Jackson M Chitanda,2 Deborah Michel,1 Jason Maley,3 Ferenc Borondics,2,4 Peng Yang,5 Ronald E Verrall,2 Ildiko Badea11Drug Design and Discovery Research Group, College of Pharmacy and Nutrition, University of Saskatchewan, 2Department of Chemistry, University of Saskatchewan, 3Saskatchewan Structural Sciences Centre, University of Saskatchewan, 4Canadian Light Source, University of Saskatchewan, Saskatoon, SK, Canada; 5Department of Organic Chemistry, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang, People's Republic of ChinaPurpose: Detonation nanodiamonds (NDs are carbon-based nanomaterials that, because of their size (4–5 nm, stable inert core, alterable surface chemistry, fluorescence, and biocompatibility, are emerging as bioimaging agents and promising tools for the delivery of biochemical molecules into cellular systems. However, diamond particles possess a strong propensity to aggregate in liquid formulation media, restricting their applicability in biomedical sciences. Here, the authors describe the covalent functionalization of NDs with lysine in an attempt to develop nanoparticles able to act as suitable nonviral vectors for transferring genetic materials across cellular membranes.Methods: NDs were oxidized and functionalized by binding lysine moieties attached to a three-carbon-length linker (1,3-diaminopropane to their surfaces through amide bonds. Raman and Fourier transform infrared spectroscopy, zeta potential measurement, dynamic light scattering, atomic force microscopic imaging, and thermogravimetric analysis were used to characterize the lysine-functionalized NDs. Finally, the ability of the functionalized diamonds to bind plasmid DNA and small interfering RNA was investigated by gel electrophoresis assay and through size and zeta potential measurements.Results: NDs were successfully functionalized with the lysine linker, producing surface loading of 1.7 mmol g-1 of ND

  6. In Vitro Transfection Mediated by Dendrigraft Poly(L-lysines): The Effect of Structure and Molecule Size

    Czech Academy of Sciences Publication Activity Database

    Hofman, J.; Bunček, M.; Haluza, R.; Streinz, Ludvík; Ledvina, Miroslav; Cígler, Petr

    2013-01-01

    Roč. 13, č. 2 (2013), s. 167-176 ISSN 1616-5187 R&D Projects: GA MŠk(CZ) LH11027; GA AV ČR KAN200100801 Institutional support: RVO:61388963 Keywords : dendrigraft poly(L-lysines) * dendrimers * drug delivery systems * structureproperty relations Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.650, year: 2013

  7. Beyond Histones: New Substrate Proteins of Lysine Deacetylases in Arabidopsis Nuclei

    Directory of Open Access Journals (Sweden)

    Magdalena Füßl

    2018-04-01

    Full Text Available The reversible acetylation of lysine residues is catalyzed by the antagonistic action of lysine acetyltransferases and deacetylases, which can be considered as master regulators of their substrate proteins. Lysine deacetylases, historically referred to as histone deacetylases, have profound functions in regulating stress defenses and development in plants. Lysine acetylation of the N-terminal histone tails promotes gene transcription and decondensation of chromatin, rendering the DNA more accessible to the transcription machinery. In plants, the classical lysine deacetylases from the RPD3/HDA1-family have thus far mainly been studied in the context of their deacetylating activities on histones, and their versatility in molecular activities is still largely unexplored. Here we discuss the potential impact of lysine acetylation on the recently identified nuclear substrate proteins of lysine deacetylases from the Arabidopsis RPD3/HDA1-family. Among the deacetylase substrate proteins, many interesting candidates involved in nuclear protein import, transcriptional regulation, and chromatin remodeling have been identified. These candidate proteins represent key starting points for unraveling new molecular functions of the Arabidopsis lysine deacetylases. Site-directed engineering of lysine acetylation sites on these target proteins might even represent a new approach for optimizing plant growth under climate change conditions.

  8. Histone lysine demethylases as targets for anticancer therapy

    DEFF Research Database (Denmark)

    Højfeldt, Jonas W; Agger, Karl; Helin, Kristian

    2013-01-01

    It has recently been demonstrated that the genes controlling the epigenetic programmes that are required for maintaining chromatin structure and cell identity include genes that drive human cancer. This observation has led to an increased awareness of chromatin-associated proteins as potentially...... interesting drug targets. The successful introduction of DNA methylation and histone deacetylase (HDAC) inhibitors for the treatment of specific subtypes of cancer has paved the way for the use of epigenetic therapy. Here, we highlight key biological findings demonstrating the roles of members of the histone...... lysine demethylase class of enzymes in the development of cancers, discuss the potential and challenges of therapeutically targeting them, and highlight emerging small-molecule inhibitors of these enzymes....

  9. Myeloperoxidase-mediated protein lysine oxidation generates 2-aminoadipic acid and lysine nitrile in vivo.

    Science.gov (United States)

    Lin, Hongqiao; Levison, Bruce S; Buffa, Jennifer A; Huang, Ying; Fu, Xiaoming; Wang, Zeneng; Gogonea, Valentin; DiDonato, Joseph A; Hazen, Stanley L

    2017-03-01

    Recent studies reveal 2-aminoadipic acid (2-AAA) is both elevated in subjects at risk for diabetes and mechanistically linked to glucose homeostasis. Prior studies also suggest enrichment of protein-bound 2-AAA as an oxidative post-translational modification of lysyl residues in tissues associated with degenerative diseases of aging. While in vitro studies suggest redox active transition metals or myeloperoxidase (MPO) generated hypochlorous acid (HOCl) may produce protein-bound 2-AAA, the mechanism(s) responsible for generation of 2-AAA during inflammatory diseases are unknown. In initial studies we observed that traditional acid- or base-catalyzed protein hydrolysis methods previously employed to measure tissue 2-AAA can artificially generate protein-bound 2-AAA from an alternative potential lysine oxidative product, lysine nitrile (LysCN). Using a validated protease-based digestion method coupled with stable isotope dilution LC/MS/MS, we now report protein bound 2-AAA and LysCN are both formed by hypochlorous acid (HOCl) and the MPO/H 2 O 2 /Cl - system of leukocytes. At low molar ratio of oxidant to target protein N ε -lysine moiety, 2-AAA is formed via an initial N ε -monochloramine intermediate, which ultimately produces the more stable 2-AAA end-product via sequential generation of transient imine and semialdehyde intermediates. At higher oxidant to target protein N ε -lysine amine ratios, protein-bound LysCN is formed via initial generation of a lysine N ε -dichloramine intermediate. In studies employing MPO knockout mice and an acute inflammation model, we show that both free and protein-bound 2-AAA, and in lower yield, protein-bound LysCN, are formed by MPO in vivo during inflammation. Finally, both 2-AAA and to lesser extent LysCN are shown to be enriched in human aortic atherosclerotic plaque, a tissue known to harbor multiple MPO-catalyzed protein oxidation products. Collectively, these results show that MPO-mediated oxidation of protein lysyl

  10. Microbial production of lysine from sustainable feedstock

    DEFF Research Database (Denmark)

    Wang, Zhihao; Grishkova, Maria; Solem, Christian

    2014-01-01

    Lysine is produced in a fermentation process using Corynebacterium glutamicum. And even though production strains have been improved for decades, there is still room for further optimization.......Lysine is produced in a fermentation process using Corynebacterium glutamicum. And even though production strains have been improved for decades, there is still room for further optimization....

  11. Methodical investigations on the determination of metabolic lysine requirements in broiler chickens. 1

    International Nuclear Information System (INIS)

    Bergner, H.; Nguyen Thi Nhan; Wilke, A.

    1987-01-01

    For the estimation of lysine requirement 128 male broiler chickens were used at an age of 7 to 21 days posthatching. They received a lysine-deficient diet composed of wheat and wheat gluten. To this basal diet L-lysine-HCL was supplemented successively resulting in 8 lysine levels ranging from 5.8 to 23.3 g lysine per kg dry matter (DM) (2.2 to 8.7 g lysine per 16 g N). At the end of the two-week feeding period of the experimental diets 14 C-lysine was injected intravenously 1.5 and 5.5 hours after feed withdrawal. During the following 4 hours the exretion of CO 2 and 14 CO 2 was measured. The highest daily gain of 21.5 g was observed in animals fed 13.3 g lysine-kg DM. Lysine concentrations exceeding 18.3 g/kg DM depressed body weight gain. The CO 2 excretion was not influenced by lysine intake. 14 CO 2 excretion was low with diets low in lysine content and increased 3 to 4 times with diets meeting the lysine requirement. Based on measurements 1.5 to 5.5 hours after feed withdrawal the saturation value for lysine was reached at 13.3 g/kg DM. This value was lowered (10.8 g/kg DM), however, if the estimation was carried out 5.5 to 9.5 hours after feed withdrawal. These results suggest a higher metabolic lysine requirement during the earlier period after feed intake. Both, reduced weight gain and non linearity in 14 CO 2 excretion in diets exceeding a lysine content of 18.3 g/kg DM indicate a limited capacity of the organism to degrade excessive lysine. According to the results a lysine requirement betwen 10.8 and 13.3 g/kg DM (27% CP and 660 EFU/sub hen//kg DM) was estimated for broiler chickens 3 weeks posthatching. (author)

  12. Maintenance requirement and deposition efficiency of lysine in pigs

    Directory of Open Access Journals (Sweden)

    Marcos Speroni Ceron

    2013-09-01

    Full Text Available The objective of this work was to determine the maintenance requirement and the deposition efficiency of lysine in growing pigs. It was used the incomplete changeover experimental design, with replicates over time. Twelve castrated pigs with average body weight (BW of 52±2 kg were kept in metabolism crates with a controlled temperature of 22ºC. The diets were formulated to supply 30, 50, 60, and 70% of the expected requirements of standardized lysine, and provided at 2.6 times the energy requirements for maintenance. The trial lasted 24 days and was divided into two periods of 12 days: seven days for animal adaptation to the diet and five days for sample collection. The increasing content of lysine in the diet did not affect dry matter intake of the pigs. The amount of nitrogen excreted was 47% of the nitrogen intake, of which 35% was excreted through feces and 65% through urine. The estimated endogenous losses of lysine were 36.4 mg kg-1 BW0.75. The maintenance requirement of lysine for pigs weighing around 50 kg is 40.4 mg kg-1 BW0.75, and the deposition efficiency of lysine is 90%.

  13. Topography of the high-affinity lysine binding site of plasminogen as defined with a specific antibody probe

    International Nuclear Information System (INIS)

    Miles, L.A.; Plow, E.F.

    1986-01-01

    An antibody population that reacted with the high-affinity lysine binding site of human plasminogen was elicited by immunizing rabbits with an elastase degradation product containing kringles 1-3 (EDP I). This antibody was immunopurified by affinity chromatography on plasminogen-Sepharose and elution with 0.2 M 6-aminohexanoic acid. The eluted antibodies bound [ 125 I]EDP I, [ 125 I]Glu-plasminogen, and [ 125 I]Lys-plasminogen in radioimmunoassays, and binding of each ligand was at least 99% inhibited by 0.2 M 6-aminohexanoic acid. The concentrations for 50% inhibition of [ 125 I]EDP I binding by tranexamic acid, 6-aminohexanoic acid, and lysine were 2.6, 46, and l730 μM, respectively. Similar values were obtained with plasminogen and suggested that an unoccupied high-affinity lysine binding site was required for antibody recognition. The antiserum reacted exclusively with plasminogen derivatives containing the EDP I region and did not react with those lacking an EDP I region, or with tissue plasminogen activator or prothrombin, which also contains kringles. By immunoblotting analyses, a chymotryptic degradation product of M/sub r/ 20,000 was derived from EDP I that retained reactivity with the antibody. α 2 -Antiplasmin inhibited the binding of radiolabeled EDP I, Glu-plasminogen, or Lys-plasminogen by the antiserum, suggesting that the recognized site is involved in the noncovalent interaction of the inhibitor with plasminogen. The binding of [ 125 I]EDP I to fibrin was also inhibited by the antiserum. The observations provide independent evidence for the role of the high-affinity lysine binding site in the functional interactions of plasminogen with its primary substrate and inhibitor

  14. New Equilibrium Models of Drug-Receptor Interactions Derived from Target-Mediated Drug Disposition.

    Science.gov (United States)

    Peletier, Lambertus A; Gabrielsson, Johan

    2018-05-14

    In vivo analyses of pharmacological data are traditionally based on a closed system approach not incorporating turnover of target and ligand-target kinetics, but mainly focussing on ligand-target binding properties. This study incorporates information about target and ligand-target kinetics parallel to binding. In a previous paper, steady-state relationships between target- and ligand-target complex versus ligand exposure were derived and a new expression of in vivo potency was derived for a circulating target. This communication is extending the equilibrium relationships and in vivo potency expression for (i) two separate targets competing for one ligand, (ii) two different ligands competing for a single target and (iii) a single ligand-target interaction located in tissue. The derived expressions of the in vivo potencies will be useful both in drug-related discovery projects and mechanistic studies. The equilibrium states of two targets and one ligand may have implications in safety assessment, whilst the equilibrium states of two competing ligands for one target may cast light on when pharmacodynamic drug-drug interactions are important. The proposed equilibrium expressions for a peripherally located target may also be useful for small molecule interactions with extravascularly located targets. Including target turnover, ligand-target complex kinetics and binding properties in expressions of potency and efficacy will improve our understanding of within and between-individual (and across species) variability. The new expressions of potencies highlight the fact that the level of drug-induced target suppression is very much governed by target turnover properties rather than by the target expression level as such.

  15. The growing landscape of lysine acetylation links metabolism and cell signalling

    DEFF Research Database (Denmark)

    Choudhary, Chuna Ram; Weinert, Brian Tate; Nishida, Yuya

    2014-01-01

    Lysine acetylation is a conserved protein post-translational modification that links acetyl-coenzyme A metabolism and cellular signalling. Recent advances in the identification and quantification of lysine acetylation by mass spectrometry have increased our understanding of lysine acetylation...

  16. Glutamic acid and its derivatives: candidates for rational design of anticancer drugs.

    Science.gov (United States)

    Ali, Imran; Wani, Waseem A; Haque, Ashanul; Saleem, Kishwar

    2013-05-01

    Throughout the history of human civilizations, cancer has been a major health problem. Its treatment has been interesting but challenging to scientists. Glutamic acid and its derivative glutamine are known to play interesting roles in cancer genesis, hence, it was realized that structurally variant glutamic acid derivatives may be designed and developed and, might be having antagonistic effects on cancer. The present article describes the state-of-art of glutamic acid and its derivatives as anticancer agents. Attempts have been made to explore the effectivity of drug-delivery systems based on glutamic acid for the delivery of anticancer drugs. Moreover, efforts have also been made to discuss the mechanism of action of glutamic acid derivatives as anticancer agents, clinical applications of glutamic acid derivatives, as well as recent developments and future perspectives of glutamic acid drug development have also been discussed.

  17. Systematic analysis of the lysine acetylome in Vibrio parahemolyticus.

    Science.gov (United States)

    Pan, Jianyi; Ye, Zhicang; Cheng, Zhongyi; Peng, Xiaojun; Wen, Liangyou; Zhao, Fukun

    2014-07-03

    Lysine acetylation of proteins is a major post-translational modification that plays an important regulatory role in almost every aspect of cells, both eukaryotes and prokaryotes. Vibrio parahemolyticus, a model marine bacterium, is a worldwide cause of bacterial seafood-borne illness. Here, we conducted the first lysine acetylome in this bacterium through a combination of highly sensitive immune-affinity purification and high-resolution LC-MS/MS. Overall, we identified 1413 lysine acetylation sites in 656 proteins, which account for 13.6% of the total proteins in the cells; this is the highest ratio of acetyl proteins that has so far been identified in bacteria. The bioinformatics analysis of the acetylome showed that the acetylated proteins are involved in a wide range of cellular functions and exhibit diverse subcellular localizations. More specifically, proteins related to protein biosynthesis and carbon metabolism are the preferential targets of lysine acetylation. Moreover, two types of acetylation motifs, a lysine or arginine at the +4/+5 positions and a tyrosine, histidine, or phenylalanine at the +1/+2 positions, were revealed from the analysis of the acetylome. Additionally, protein interaction network analysis demonstrates that a wide range of interactions are modulated by protein acetylation. This study provides a significant beginning for the in-depth exploration of the physiological role of lysine acetylation in V. parahemolyticus.

  18. Impact of Variety and Agronomic Factors on Crude Protein and Total Lysine in Chicory; N(ε)-Carboxymethyl-lysine-Forming Potential during Drying and Roasting.

    Science.gov (United States)

    Loaëc, Grégory; Niquet-Léridon, Céline; Henry, Nicolas; Jacolot, Philippe; Jouquand, Céline; Janssens, Myriam; Hance, Philippe; Cadalen, Thierry; Hilbert, Jean-Louis; Desprez, Bruno; Tessier, Frédéric J

    2015-12-02

    During the heat treatment of coffee and its substitutes some compounds potentially deleterious to health are synthesized by the Maillard reaction. Among these, N(ε)-carboxymethyl-lysine (CML) was detected at high levels in coffee substitutes. The objective of this study was to evaluate the impact of changes in agricultural practice on the lysine content present in chicory roots and try to limit CML formation during roasting. Of the 24 varieties analyzed, small variations in lysine content were observed, 213 ± 8 mg/100 g dry matter (DM). The formation of lysine tested in five commercial varieties was affected by the nitrogen treatment with mean levels of 176 ± 2 mg/100 g DM when no fertilizer was added and 217 ± 7 mg/100 g DM with a nitrogen supply of 120 kg/ha. The lysine content of fresh roots was significantly correlated to the concentration of CML formed in roasted roots (r = 0.51; p < 0.0001; n = 76).

  19. Delivery of chemotherapeutic drugs in tumour cell-derived microparticles.

    Science.gov (United States)

    Tang, Ke; Zhang, Yi; Zhang, Huafeng; Xu, Pingwei; Liu, Jing; Ma, Jingwei; Lv, Meng; Li, Dapeng; Katirai, Foad; Shen, Guan-Xin; Zhang, Guimei; Feng, Zuo-Hua; Ye, Duyun; Huang, Bo

    2012-01-01

    Cellular microparticles are vesicular plasma membrane fragments with a diameter of 100-1,000 nanometres that are shed by cells in response to various physiological and artificial stimuli. Here we demonstrate that tumour cell-derived microparticles can be used as vectors to deliver chemotherapeutic drugs. We show that tumour cells incubated with chemotherapeutic drugs package these drugs into microparticles, which can be collected and used to effectively kill tumour cells in murine tumour models without typical side effects. We describe several mechanisms involved in this process, including uptake of drug-containing microparticles by tumour cells, synthesis of additional drug-packaging microparticles by these cells that contribute to the cytotoxic effect and the inhibition of drug efflux from tumour cells. This study highlights a novel drug delivery strategy with potential clinical application.

  20. CPLA 1.0: an integrated database of protein lysine acetylation.

    Science.gov (United States)

    Liu, Zexian; Cao, Jun; Gao, Xinjiao; Zhou, Yanhong; Wen, Longping; Yang, Xiangjiao; Yao, Xuebiao; Ren, Jian; Xue, Yu

    2011-01-01

    As a reversible post-translational modification (PTM) discovered decades ago, protein lysine acetylation was known for its regulation of transcription through the modification of histones. Recent studies discovered that lysine acetylation targets broad substrates and especially plays an essential role in cellular metabolic regulation. Although acetylation is comparable with other major PTMs such as phosphorylation, an integrated resource still remains to be developed. In this work, we presented the compendium of protein lysine acetylation (CPLA) database for lysine acetylated substrates with their sites. From the scientific literature, we manually collected 7151 experimentally identified acetylation sites in 3311 targets. We statistically studied the regulatory roles of lysine acetylation by analyzing the Gene Ontology (GO) and InterPro annotations. Combined with protein-protein interaction information, we systematically discovered a potential human lysine acetylation network (HLAN) among histone acetyltransferases (HATs), substrates and histone deacetylases (HDACs). In particular, there are 1862 triplet relationships of HAT-substrate-HDAC retrieved from the HLAN, at least 13 of which were previously experimentally verified. The online services of CPLA database was implemented in PHP + MySQL + JavaScript, while the local packages were developed in JAVA 1.5 (J2SE 5.0). The CPLA database is freely available for all users at: http://cpla.biocuckoo.org.

  1. Design of Drug Delivery Systems Containing Artemisinin and Its Derivatives

    Directory of Open Access Journals (Sweden)

    Blessing Atim Aderibigbe

    2017-02-01

    Full Text Available Artemisinin and its derivatives have been reported to be experimentally effective for the treatment of highly aggressive cancers without developing drug resistance, they are useful for the treatment of malaria, other protozoal infections and they exhibit antiviral activity. However, they are limited pharmacologically by their poor bioavailability, short half-life in vivo, poor water solubility and long term usage results in toxicity. They are also expensive for the treatment of malaria when compared to other antimalarials. In order to enhance their therapeutic efficacy, they are incorporated onto different drug delivery systems, thus yielding improved biological outcomes. This review article is focused on the currently synthesized derivatives of artemisinin and different delivery systems used for the incorporation of artemisinin and its derivatives.

  2. Threonine and lysine requirements for maintenance in chickens ...

    African Journals Online (AJOL)

    The maintenance requirement for threonine and lysine were estimated in two different experiments by measuring the nitrogen balance of adult male cockerels. Measured amounts of a diet first-limiting in threonine or lysine were fed by intubation each day for 4 d to give a range of intakes (unbalanced series) of from 0 to 239 ...

  3. Structural aspects of the solvation shell of lysine and acetylated lysine: A Car-Parrinello and classical molecular dynamics investigation

    International Nuclear Information System (INIS)

    Carnevale, V.; Raugei, S.

    2009-01-01

    Lysine acetylation is a post-translational modification, which modulates the affinity of protein-protein and/or protein-DNA complexes. Its crucial role as a switch in signaling pathways highlights the relevance of charged chemical groups in determining the interactions between water and biomolecules. A great effort has been recently devoted to assess the reliability of classical molecular dynamics simulations in describing the solvation properties of charged moieties. In the spirit of these investigations, we performed classical and Car-Parrinello molecular dynamics simulations on lysine and acetylated-lysine in aqueous solution. A comparative analysis between the two computational schemes is presented with a focus on the first solvation shell of the charged groups. An accurate structural analysis unveils subtle, yet statistically significant, differences which are discussed in connection to the significant electronic density charge transfer occurring between the solute and the surrounding water molecules.

  4. Conformational Studies of ε- CBz- L- Lysine and L- Valine Block Copolypeptides

    Directory of Open Access Journals (Sweden)

    Ajay Kumar

    2010-01-01

    Full Text Available Conformational studies of ε-CBz-L-lysine and L-valine block copoylpeptides using x- ray diffraction and CD spectra are described. The block copolypeptides contain valine block in the center and on both side of the valine are ε-CBz-L-lysine blocks. The conformation of the copolypeptides changes with increases in the chain length of ε- CBz-L- lysine blocks. When length of ε- CBZ- L- lysine blocks is 9, the block copolypeptide has exclusive beta sheet structure. With the increase in chain length of ε-CBz-L-lysine blocks from 9 to 14, the block copolypeptide shows presence of both alpha helix and beta sheet components. With further increase in chain length of ε- CBz- L- lysine blocks, the beta sheet component disappears and block copolypeptides exhibits exclusive α -helix conformation.

  5. Biomaterial-Derived Calcium Carbonate Nanoparticles for Enteric Drug Delivery

    Directory of Open Access Journals (Sweden)

    Diane Render

    2016-01-01

    Full Text Available Oral drug delivery systems provide the most convenient, noninvasive, readily acceptable alternatives to parenteral systems. In the current work, eggshell-derived calcium carbonate (CaCO3 nanoparticles were used to develop enteric drug delivery system in the form of tablets. CaCO3 nanoparticles were manufactured using top-down ball-milling method and characterized by X-ray diffractometry (XRD and transmission electron microscopy (TEM and loaded with 5-fluorouracil as a model drug. Tablets with varying CaCO3 core and binder compositions were fabricated and coated with Eudragit S100 or Eudragit L100. Suitability for enteric delivery of the tablets was tested by oral administration to rabbits and radiography. Radiograph images showed that the tablet remained in the stomach of the rabbit for up to 3 hours. Further modifications of these biomaterial-derived nanoparticles and the coatings will enable manufacturing of stable formulations for slow or controlled release of pharmaceuticals for enteric delivery.

  6. Human induced pluripotent stem cell (hiPSC)-derived neurons respond to convulsant drugs when co-cultured with hiPSC-derived astrocytes.

    Science.gov (United States)

    Ishii, Misawa Niki; Yamamoto, Koji; Shoji, Masanobu; Asami, Asano; Kawamata, Yuji

    2017-08-15

    Accurate risk assessment for drug-induced seizure is expected to be performed before entering clinical studies because of its severity and fatal damage to drug development. Induced pluripotent stem cell (iPSC) technology has allowed the use of human neurons and glial cells in toxicology studies. Recently, several studies showed the advantage of co-culture system of human iPSC (hiPSC)-derived neurons with rodent/human primary astrocytes regarding neuronal functions. However, the application of hiPSC-derived neurons for seizure risk assessment has not yet been fully addressed, and not at all when co-cultured with hiPSC-derived astrocytes. Here, we characterized hiPSC-derived neurons co-cultured with hiPSC-derived astrocytes to discuss how hiPSC-derived neurons are useful to assess seizure risk of drugs. First, we detected the frequency of spikes and synchronized bursts hiPSC-derived neurons when co-cultured with hiPSC-derived astrocytes for 8 weeks. This synchronized burst was suppressed by the treatment with 6-cyano-7-nitroquinoxaline-2,3-dione, α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor antagonist, and D-(-)-2-amino-5-phosphonopentanoic acid, an N-Methyl-d-aspartate (NMDA) receptor antagonist. These data suggested that co-cultured hiPSC-derived neurons formed synaptic connections mediated by AMPA and NMDA receptors. We also demonstrated that co-cultured hiPSC-derived neurons showed epileptiform activity upon treatment with gabazine or kaliotoxin. Finally, we performed single-cell transcriptome analysis in hiPSC-derived neurons and found that hiPSC-derived astrocytes activated the pathways involved in the activities of AMPA and NMDA receptor functions, neuronal polarity, and axon guidance in hiPSC-derived neurons. These data suggested that hiPSC-derived astrocytes promoted the development of action potential, synaptic functions, and neuronal networks in hiPSC-derived neurons, and then these functional alterations result in the epileptiform

  7. Lysine requirement of White Leghorn pullets from 8 to 21 weeks of age.

    Science.gov (United States)

    Berg, L R

    1976-01-01

    White Leghorn pullets were fed rations in which the protein supplementary to that provided by the grain portion of the ration was derived from soybean meal, meat and bone meal, anchovy fish meal or cottonseed meal from 8 to 21 weeks of age. Protein levels were varied so that each protein supplement was tested in a feeding program in which pullets received 16% protein diets from 8 to 14 weeks and 14% protein from 14 to 21 weeks and in another feeding program in which 14% protein was fed from 8 to 14 weeks and 12% protein from 14 to 21 weeks. Each of the developing rations contained sufficient nutrient to enable pullets to develop and attain high rate of laying performance. The 14% and 12% protein cottonseed meal diets contained only 0.50% and 0.45% lysine respectively. Thus the lysine requirement of White Leghorn pullets from 8 to 14 weeks and from 14 to 21 weeks is not over 0.50% and 0.45% respectively.

  8. Safely diagnosing clinically significant penicillin allergy using only penicilloyl-poly-lysine, penicillin, and oral amoxicillin.

    Science.gov (United States)

    Macy, Eric; Ngor, Eunis W

    2013-01-01

    Penicillin skin testing is rarely used to undiagnose penicillin "allergy" in the United States, partially because of concern that commercially available materials are inadequate. We determined whether skin testing with only commercially available penicilloyl-poly-lysine and penicillin followed by an oral amoxicillin challenge, if skin test-negative, can safely identify clinically significant penicillin allergy. Five hundred sequential persons with positive history of penicillin "allergy" were evaluated by skin testing with penicilloyl-poly-lysine and penicillin between June 8, 2010, and March 29, 2012. All persons with negative skin tests were given an oral amoxicillin challenge and observed for 1 hour. Persons undergoing penicillin allergy testing were representative of all health plan members with penicillin allergy. Only 4 persons (0.8%; 95% CI, 0.32%-2.03%) had a positive skin test result. Only 4 persons (0.8%; 95% CI, 0.32%-2.03%) had an acute objective oral amoxicillin challenge reaction. Fifteen persons (3.0%; 95% CI, 1.83%-4.98%) had subjective oral challenge reactions, either acute transient itching or dizziness. All were women and 11 (73.3%) had multiple drug intolerance syndrome. None had severe reactions or objective signs. These were not considered to be positive challenge reactions. Sixty-eight subjects (13.6%) who were negative on testing were exposed to 88 courses of penicillins during 90 days of follow-up. New reactions were reported after 4 courses (4.5%), 3 (75%) occurring in subjects with multiple drug intolerance syndrome. Penicillin skin testing, using only penicilloyl-poly-lysine and penicillin, followed by oral amoxicillin challenge, if negative, can safely identify clinically significant IgE-mediated penicillin allergy in patients who use health care in the United States at this time. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  9. Chemical mechanisms of histone lysine and arginine modifications

    OpenAIRE

    Smith, Brian C.; Denu, John M.

    2008-01-01

    Histone lysine and arginine residues are subject to a wide array of post-translational modifications including methylation, citrullination, acetylation, ubiquitination, and sumoylation. The combinatorial action of these modifications regulates critical DNA processes including replication, repair, and transcription. In addition, enzymes that modify histone lysine and arginine residues have been correlated with a variety of human diseases including arthritis, cancer, heart disease, diabetes, an...

  10. ß-Lysine discrimination by lysyl-tRNA synthetase

    DEFF Research Database (Denmark)

    Gilreath, Marla S; Roy, Hervé; Bullwinkle, Tammy J

    2011-01-01

    guided by the PoxA structure. A233S LysRS behaved as wild type with a-lysine, while the G469A and A233S/G469A variants decreased stable a-lysyl-adenylate formation. A233S LysRS recognized ß-lysine better than wildtype, suggesting a role for this residue in discriminating a- and ß-amino acids. Both...

  11. Comprehensive Proteomic Analysis of Lysine Acetylation in the Foodborne Pathogen Trichinella spiralis

    Directory of Open Access Journals (Sweden)

    Yong Yang

    2018-01-01

    Full Text Available Lysine acetylation is a dynamic and highly conserved post-translational modification that plays a critical role in regulating diverse cellular processes. Trichinella spiralis is a foodborne parasite with a considerable socio-economic impact. However, to date, little is known regarding the role of lysine acetylation in this parasitic nematode. In this study, we utilized a proteomic approach involving anti-acetyl lysine-based enrichment and highly sensitive mass spectrometry to identify the global acetylated proteome and investigate lysine acetylation in T. spiralis. In total, 3872 lysine modification sites were identified in 1592 proteins that are involved in a wide variety of biological processes. Consistent with the results of previous studies, a large number of the acetylated proteins appear to be involved in metabolic and biosynthetic processes. Interestingly, according to the functional enrichment analysis, 29 acetylated proteins were associated with phagocytosis, suggesting an important role of lysine acetylation in this process. Among the identified proteins, 15 putative acetylation motifs were detected. The presence of serine downstream of the lysine acetylation site was commonly observed in the regions surrounding the sites. Moreover, protein interaction network analysis revealed that various interactions are regulated by protein acetylation. These data represent the first report of the acetylome of T. spiralis and provide an important resource for further explorations of the role of lysine acetylation in this foodborne pathogen.

  12. Core/shell cellulose-based microspheres for oral administration of Ketoprofen Lysinate.

    Science.gov (United States)

    Guarino, Vincenzo; Caputo, Tania; Calcagnile, Paola; Altobelli, Rosaria; Demitri, Christian; Ambrosio, Luigi

    2018-01-26

    Herein, we propose the fabrication of a new carrier with core/shell structure-inner core of cellulose acetate (CA) coated by a micrometric layer of chitosan (CS)-fabricated through an integrated process, which combines Electro Dynamic Atomization (EDA) and layer-by-layer (LbL) technique. We demonstrate that CA based microspheres possess a unique capability to relevantly retain the drugs-that is, Ketoprofen Lysinate (KL)-along the gastric tract, while providing a massive release along the intestine. CS shell slightly influences the morphology and water retention under different pH conditions, improving drug encapsulation without compromising drug release kinetics. In vitro studies in simulated gastric and intestine fluids (SGF, SIF) with physiological enzymes, show a moderate release of LSK during the first 2 h (ca. 20% at pH 2), followed by a sustained release during the next 6 h (ca. 80% at pH 7). The obtained results demonstrate that CA-based microspheres hold strong potential to be used as carriers for a delayed oral administration of anti-inflammatory drugs. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2018. © 2018 Wiley Periodicals, Inc.

  13. Cyclophilin-B Modulates Collagen Cross-linking by Differentially Affecting Lysine Hydroxylation in the Helical and Telopeptidyl Domains of Tendon Type I Collagen.

    Science.gov (United States)

    Terajima, Masahiko; Taga, Yuki; Chen, Yulong; Cabral, Wayne A; Hou-Fu, Guo; Srisawasdi, Sirivimol; Nagasawa, Masako; Sumida, Noriko; Hattori, Shunji; Kurie, Jonathan M; Marini, Joan C; Yamauchi, Mitsuo

    2016-04-29

    Covalent intermolecular cross-linking provides collagen fibrils with stability. The cross-linking chemistry is tissue-specific and determined primarily by the state of lysine hydroxylation at specific sites. A recent study on cyclophilin B (CypB) null mice, a model of recessive osteogenesis imperfecta, demonstrated that lysine hydroxylation at the helical cross-linking site of bone type I collagen was diminished in these animals (Cabral, W. A., Perdivara, I., Weis, M., Terajima, M., Blissett, A. R., Chang, W., Perosky, J. E., Makareeva, E. N., Mertz, E. L., Leikin, S., Tomer, K. B., Kozloff, K. M., Eyre, D. R., Yamauchi, M., and Marini, J. C. (2014) PLoS Genet 10, e1004465). However, the extent of decrease appears to be tissue- and molecular site-specific, the mechanism of which is unknown. Here we report that although CypB deficiency resulted in lower lysine hydroxylation in the helical cross-linking sites, it was increased in the telopeptide cross-linking sites in tendon type I collagen. This resulted in a decrease in the lysine aldehyde-derived cross-links but generation of hydroxylysine aldehyde-derived cross-links. The latter were absent from the wild type and heterozygous mice. Glycosylation of hydroxylysine residues was moderately increased in the CypB null tendon. We found that CypB interacted with all lysyl hydroxylase isoforms (isoforms 1-3) and a putative lysyl hydroxylase-2 chaperone, 65-kDa FK506-binding protein. Tendon collagen in CypB null mice showed severe size and organizational abnormalities. The data indicate that CypB modulates collagen cross-linking by differentially affecting lysine hydroxylation in a site-specific manner, possibly via its interaction with lysyl hydroxylases and associated molecules. This study underscores the critical importance of collagen post-translational modifications in connective tissue formation. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Cyclophilin-B Modulates Collagen Cross-linking by Differentially Affecting Lysine Hydroxylation in the Helical and Telopeptidyl Domains of Tendon Type I Collagen*

    Science.gov (United States)

    Terajima, Masahiko; Taga, Yuki; Chen, Yulong; Cabral, Wayne A.; Hou-Fu, Guo; Srisawasdi, Sirivimol; Nagasawa, Masako; Sumida, Noriko; Hattori, Shunji; Kurie, Jonathan M.; Marini, Joan C.; Yamauchi, Mitsuo

    2016-01-01

    Covalent intermolecular cross-linking provides collagen fibrils with stability. The cross-linking chemistry is tissue-specific and determined primarily by the state of lysine hydroxylation at specific sites. A recent study on cyclophilin B (CypB) null mice, a model of recessive osteogenesis imperfecta, demonstrated that lysine hydroxylation at the helical cross-linking site of bone type I collagen was diminished in these animals (Cabral, W. A., Perdivara, I., Weis, M., Terajima, M., Blissett, A. R., Chang, W., Perosky, J. E., Makareeva, E. N., Mertz, E. L., Leikin, S., Tomer, K. B., Kozloff, K. M., Eyre, D. R., Yamauchi, M., and Marini, J. C. (2014) PLoS Genet. 10, e1004465). However, the extent of decrease appears to be tissue- and molecular site-specific, the mechanism of which is unknown. Here we report that although CypB deficiency resulted in lower lysine hydroxylation in the helical cross-linking sites, it was increased in the telopeptide cross-linking sites in tendon type I collagen. This resulted in a decrease in the lysine aldehyde-derived cross-links but generation of hydroxylysine aldehyde-derived cross-links. The latter were absent from the wild type and heterozygous mice. Glycosylation of hydroxylysine residues was moderately increased in the CypB null tendon. We found that CypB interacted with all lysyl hydroxylase isoforms (isoforms 1–3) and a putative lysyl hydroxylase-2 chaperone, 65-kDa FK506-binding protein. Tendon collagen in CypB null mice showed severe size and organizational abnormalities. The data indicate that CypB modulates collagen cross-linking by differentially affecting lysine hydroxylation in a site-specific manner, possibly via its interaction with lysyl hydroxylases and associated molecules. This study underscores the critical importance of collagen post-translational modifications in connective tissue formation. PMID:26934917

  15. Cholestane derivatives as antitumor and antiangiogenic drugs

    Czech Academy of Sciences Publication Activity Database

    Hoffmannová, L.; Steigerová, J.; Oklešťková, J.; Kohout, Ladislav; Chodounská, Hana; Hniličková, Jaroslava; Kasal, Alexander; Černý, Ivan; Kolář, Z.; Strnad, M.

    2010-01-01

    Roč. 35, SA (2010), s. 205-205 ISSN 0377-8282. [EFMC-ISMC 2010. International Symposium on Medicinal Chemistry /21./. 05.09.2010-09.09.2010, Brussels] R&D Projects: GA MŠk(CZ) LC06077; GA AV ČR KAN200200651 Institutional research plan: CEZ:AV0Z40550506 Keywords : cholestane derivatives * anticancer drugs Subject RIV: CC - Organic Chemistry

  16. Antibiotic and surfactant effects on lysine accumulation by Bacillus ...

    African Journals Online (AJOL)

    The effects of antibiotics and surfactants on lysine accumulation in the culture broth of three strains of Bacillus megaterium (B. megaterium SP 86, B. megaterium SP 76 and B. megaterium SP 14) were investigated. Lincomycin, neomycin and tetracycline stimulated lysine increase in B. megaterium SP 76 and B. megaterium ...

  17. Copper nanoclusters as probes for turn-on fluorescence sensing of L-lysine.

    Science.gov (United States)

    Zhang, Mingming; Qiao, Juan; Zhang, Shufeng; Qi, Li

    2018-05-15

    Herein, a unique protocol based on copper nanoclusters (CuNCs) probe for turn-on fluorescence sensing of L-lysine was developed. The fluorescent CuNCs with ovalbumin as the stabilizer was prepared by a simple, one-step and green method. When 370 nm was used as the excitation wavelength, the resultant CuNCs exhibited a pale blue fluorescence with the maximum emission at 440 nm. Interestingly, existence of L-lysine evoked the obvious fluorescence intensity increase of CuNCs. The detection limit of the proposed method for L-lysine was 5.5 μM, with a good linear range from 10.0 μM to 1.0 mM (r 2 = 0.999). Moreover, the possible mechanism for enhanced fluorescence intensity of CuNCs by addition of L-lysine was explored and discussed briefly. Further, the as-prepared fluorescent CuNCs was successfully applied in detection of L-lysine in urine. Our results demonstrated that L-lysine could be monitored by the probe, providing new path for construction of CuNCs as fluorescent probes and showing great potential in quantification of L-lysine in real samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Mass spectrometric characterization of circulating and functional antigens derived from piperacillin in patients with cystic fibrosis1

    Science.gov (United States)

    Whitaker, Paul; Meng, Xiaoli; Lavergne, Sidonie N.; El-Ghaiesh, Sabah; Monshi, Manal; Earnshaw, Caroline; Peckham, Daniel; Gooi, Jimmy; Conway, Steve; Pirmohamed, Munir; Jenkins, Rosalind E.; Naisbitt, Dean J.; Park, B. Kevin

    2011-01-01

    A mechanistic understanding of the relationship between the chemistry of drug antigen formation and immune function is lacking. Thus, mass spectrometric methods were employed to detect and fully characterize circulating antigens derived from piperacillin in patients undergoing therapy and the nature of the drug derived-epitopes on protein which can function as an antigen to stimulate T-cells. Albumin modification with piperacillin in vitro resulted in the formation of two distinct haptens, one formed directly from piperacillin and a second in which the dioxopiperazine ring had undergone hydrolysis. Modification was time- and concentration-dependent, with selective modification of Lys541 observed at low concentrations, whereas at higher concentrations up to 13/59 lysine residues were modified, four of which (Lys190, 195, 432 and 541) were detected in patients’ plasma. Piperacillin-specific T-lymphocyte responses (proliferation, cytokines and granzyme-B release) were detected ex vivo with cells from hypersensitive patients, and analysis of incubation medium showed that modification of the same lysine residues in albumin occurred in situ. The antigenicity of piperacillin-modified albumin was confirmed by stimulation of T-cells with characterized synthetic conjugates. Analysis of minimally-modified T-cell stimulatory albumin conjugates revealed peptide sequences incorporating Lys190, 432 and 541 as principal functional epitopes for T-cells. This study has characterized the multiple haptenic structures on albumin in patients, and showed that they constitute functional antigenic determinants for T-cells. PMID:21606251

  19. Widespread occurrence of lysine methylation in Plasmodium falciparum proteins at asexual blood stages.

    Science.gov (United States)

    Kaur, Inderjeet; Zeeshan, Mohammad; Saini, Ekta; Kaushik, Abhinav; Mohmmed, Asif; Gupta, Dinesh; Malhotra, Pawan

    2016-10-20

    Post-transcriptional and post-translational modifications play a major role in Plasmodium life cycle regulation. Lysine methylation of histone proteins is well documented in several organisms, however in recent years lysine methylation of proteins outside histone code is emerging out as an important post-translational modification (PTM). In the present study we have performed global analysis of lysine methylation of proteins in asexual blood stages of Plasmodium falciparum development. We immunoprecipitated stage specific Plasmodium lysates using anti-methyl lysine specific antibodies that immunostained the asexual blood stage parasites. Using liquid chromatography and tandem mass spectrometry analysis, 570 lysine methylated proteins at three different blood stages were identified. Analysis of the peptide sequences identified 605 methylated sites within 422 proteins. Functional classification of the methylated proteins revealed that the proteins are mainly involved in nucleotide metabolic processes, chromatin organization, transport, homeostatic processes and protein folding. The motif analysis of the methylated lysine peptides reveals novel motifs. Many of the identified lysine methylated proteins are also interacting partners/substrates of PfSET domain proteins as revealed by STRING database analysis. Our findings suggest that the protein methylation at lysine residues is widespread in Plasmodium and plays an important regulatory role in diverse set of the parasite pathways.

  20. Utility of Glioblastoma Patient-Derived Orthotopic Xenografts in Drug Discovery and Personalized Therapy

    Directory of Open Access Journals (Sweden)

    Michele Patrizii

    2018-02-01

    Full Text Available Despite substantial effort and resources dedicated to drug discovery and development, new anticancer agents often fail in clinical trials. Among many reasons, the lack of reliable predictive preclinical cancer models is a fundamental one. For decades, immortalized cancer cell cultures have been used to lay the groundwork for cancer biology and the quest for therapeutic responses. However, cell lines do not usually recapitulate cancer heterogeneity or reveal therapeutic resistance cues. With the rapidly evolving exploration of cancer “omics,” the scientific community is increasingly investigating whether the employment of short-term patient-derived tumor cell cultures (two- and three-dimensional and/or patient-derived xenograft models might provide a more representative delineation of the cancer core and its therapeutic response. Patient-derived cancer models allow the integration of genomic with drug sensitivity data on a personalized basis and currently represent the ultimate approach for preclinical drug development and biomarker discovery. The proper use of these patient-derived cancer models might soon influence clinical outcomes and allow the implementation of tailored personalized therapy. When assessing drug efficacy for the treatment of glioblastoma multiforme (GBM, currently, the most reliable models are generated through direct injection of patient-derived cells or more frequently the isolation of glioblastoma cells endowed with stem-like features and orthotopically injecting these cells into the cerebrum of immunodeficient mice. Herein, we present the key strengths, weaknesses, and potential applications of cell- and animal-based models of GBM, highlighting our experience with the glioblastoma stem-like patient cell-derived xenograft model and its utility in drug discovery.

  1. Use of acetimidation in the NMR identification of neurophysin lysine protons

    International Nuclear Information System (INIS)

    Sardana, V.; Breslow, E.

    1986-01-01

    Acetimidation of the two lysine residues of neurophysin (NP) results in localized changes in the proton magnetic resonance spectrum, allowing identification of lysine side-chain resonances. Neither peptide-binding nor protein self-association appeared to be significantly altered by acetimidation. Additionally, no significant effect of either peptide-binding or self-association on lysine epsilon-CH 2 protons was seen. However, dimerization-induced NMR changes in the 1.6-1.8 ppm region, associated with lysine β,γ,σ protons, were altered in the acetimidated protein. In particular, while the spectrum of the acetimidated NP monomer was almost identical to that of the native protein, a shoulder at 1.72 ppm in the native protein dimer was shifted upfield in the modified dimer. Additionally the direction of NMR shifts in the 1.6-1.8 ppm region normally associated with peptide binding to the NP dimer appeared to be reversed in the acetimidated protein. Binding-induced and dimerization-induced changes in all other regions of the spectrum were identical in the native and modified proteins. These results suggest that one or both NP lysine residues may be near the dimer subunit interface and indicate an effect of peptide-binding on lysine side-chain environment

  2. Interaction of L-lysine and soluble elastin with the semicarbazide-sensitive amine oxidase in the context of its vascular-adhesion and tissue maturation functions.

    LENUS (Irish Health Repository)

    Olivieri, Aldo

    2010-04-01

    The copper-containing quinoenzyme semicarbazide-sensitive amine oxidase (EC 1.4.3.21; SSAO) is a multifunctional protein. In some tissues, such as the endothelium, it also acts as vascular-adhesion protein 1 (VAP-1), which is involved in inflammatory responses and in the chemotaxis of leukocytes. Earlier work had suggested that lysine might function as a recognition molecule for SSAO\\/VAP-1. The present work reports the kinetics of the interaction of L-lysine and some of its derivatives with SSAO. Binding was shown to be saturable, time-dependent but reversible and to cause uncompetitive inhibition with respect to the amine substrate. It was also specific, since D-lysine, L-lysine ethyl ester and epsilon-acetyl-L-lysine, for example, did not bind to the enzyme. The lysine-rich protein soluble elastin bound to the enzyme relatively tightly, which may have relevance to the reported roles of SSAO in maintaining the extracellular matrix (ECM) and in the maturation of elastin. Our data show that lysyl residues are not oxidized by SSAO, but they bind tightly to the enzyme in the presence of hydrogen peroxide. This suggests that binding in vivo of SSAO to lysyl residues in physiological targets might be regulated in the presence of H(2)O(2), formed during the oxidation of a physiological SSAO substrate, yet to be identified.

  3. Crystallization and preliminary X-ray analysis of the inducible lysine decarboxylase from Escherichia coli

    International Nuclear Information System (INIS)

    Alexopoulos, Eftichia; Kanjee, Usheer; Snider, Jamie; Houry, Walid A.; Pai, Emil F.

    2008-01-01

    The structure of the decameric inducible lysine decarboxylase from E. coli was determined by SIRAS using a hexatantalum dodecabromide (Ta 6 Br 12 2+ ) derivative. Model building and refinement are under way. The decameric inducible lysine decarboxylase (LdcI) from Escherichia coli has been crystallized in space groups C2 and C222 1 ; the Ta 6 Br 12 2+ cluster was used to derivatize the C2 crystals. The method of single isomorphous replacement with anomalous scattering (SIRAS) as implemented in SHELXD was used to solve the Ta 6 Br 12 2+ -derivatized structure to 5 Å resolution. Many of the Ta 6 Br 12 2+ -binding sites had twofold and fivefold noncrystallographic symmetry. Taking advantage of this feature, phase modification was performed in DM. The electron-density map of LdcI displays many features in agreement with the low-resolution negative-stain electron-density map [Snider et al. (2006 ▶), J. Biol. Chem.281, 1532–1546

  4. Optimization of lysine production in Corynebacteriumglutamicum ATCC15032 by Response surface methodology

    Directory of Open Access Journals (Sweden)

    Mehrnaz Haghi

    2017-03-01

    Discussion and conclusion: According to the results, the proposed culture media by response surface methodology causes 1400 times increase in the lysine production compared with M9 culture media and methionine had an important role in the production of lysine, probably by inhibiting the other metabolic pathway which has common metabolic precursor with lysine production metabolic pathway.

  5. Characterization of Agronomy, Grain Physicochemical Quality, and Nutritional Property of High-Lysine 35R Transgenic Rice with Simultaneous Modification of Lysine Biosynthesis and Catabolism.

    Science.gov (United States)

    Yang, Qingqing; Wu, Hongyu; Li, Qianfeng; Duan, Ruxu; Zhang, Changquan; Sun, Samuel Saiming; Liu, Qiaoquan

    2017-05-31

    Lysine is the first limiting essential amino acid in rice. We previously constructed a series of transgenic rice lines to enhance lysine biosynthesis (35S), down-regulate its catabolism (Ri), or simultaneously achieve both metabolic effects (35R). In this study, nine transgenic lines, three from each group, were selected for both field and animal feeding trials. The results showed that the transgene(s) caused no obvious effects on field performance and main agronomic traits. Mature seeds of transgenic line 35R-17 contained 48-60-fold more free lysine than in wild type and had slightly lower apparent amylose content and softer gel consistency. Moreover, a 35-day feeding experiment showed that the body weight gain, food efficiency, and protein efficiency ratio of rats fed the 35R-17 transgenic rice diet were improved when compared with those fed wild-type rice diet. These data will be useful for further evaluation and potential commercialization of 35R high-lysine transgenic rice.

  6. Glycated Lysine Residues: A Marker for Non-Enzymatic Protein Glycation in Age-Related Diseases

    Directory of Open Access Journals (Sweden)

    Nadeem A. Ansari

    2011-01-01

    Full Text Available Nonenzymatic glycosylation or glycation of macromolecules, especially proteins leading to their oxidation, play an important role in diseases. Glycation of proteins primarily results in the formation of an early stage and stable Amadori-lysine product which undergo further irreversible chemical reactions to form advanced glycation endproducts (AGEs. This review focuses these products in lysine rich proteins such as collagen and human serum albumin for their role in aging and age-related diseases. Antigenic characteristics of glycated lysine residues in proteins together with the presence of serum autoantibodies to the glycated lysine products and lysine-rich proteins in diabetes and arthritis patients indicates that these modified lysine residues may be a novel biomarker for protein glycation in aging and age-related diseases.

  7. An Update on Lysine Deacylases Targeting the Expanding “Acylome”

    DEFF Research Database (Denmark)

    Olsen, Christian Adam

    2013-01-01

    Lysine e-amino acetylation has long been recognized as an epigenetically relevant post-translational modification of multiple residues in histone proteins. However, it has become clear that lysine acetylation is not restricted to histones, and therefore, it may be involved in the regulation of a ...

  8. METHODS FOR DETERMINATION REACTIVE LYSINE IN HEAT-TREATED FOODS AND FEEDS

    Directory of Open Access Journals (Sweden)

    Matej Brestenský

    2014-08-01

    Full Text Available Lysine is an essential amino acid, which is limited in foods of plant origin, especially in cereals. The heat-treatment of products containing proteins and reducing sugars results in formation of Maillard reactions during which the cross-linkages among epsilon amino groups (ε-NH2 and reducing sugars are created. Thus the protein-carbohydrate complex is formed. This complex contains an unreactive (unavailable lysine, which is bound to reducing sugars and is not available in body. Hereby, the nutritive value of feeds and foods decreases. When a standard analytical method for analyses of amino acids is used, in products containing protein-carbohydrate complexes, it is not possible to analyze the content of reactive (available and unreactive (unavailable lysine, but only the content of total lysine. Therefore, when the standard amino acid analysis is used, the content of lysine in heat-treated feeds and foods is overestimated. In order to avoid this, some methods for determination of reactive lysine were developed. Among the best known, the homoarginine and furosine methods are included. Using these methods, in evaluation of nutritive value of feeds and foods, is of great importance because they allow to determine the extent of proteins, which were damaged during the heat treatment and thus we obtain information on objective nutritional protein quality of the product.

  9. Structural dynamics and quantum mechanical aspects of shikonin derivatives as CREBBP bromodomain inhibitors.

    Science.gov (United States)

    Mitra, Sarmistha; Dash, Raju

    2018-05-04

    The Proteins involved in the chemical modification of lysine residues in histone, is currently being excessively focused as the therapeutic target for the treatment of cell related diseases like cancer. Among these proteins, the epigenetic reader, CREB-binding protein (CREBBP) bromodomain is one of the most prominent targets for effective anticancer drug design, which is responsible for the reorganization of acetylated histone lysine residues. Therefore, this study employed an integrative approach of structure based drug design, in combination with Molecular Dynamics (MD) and QM/MM study to identify as well as to describe the binding mechanism of two shikonin derivatives, acetylshikonin and propionylshikonin as inhibitors of CREBBP bromodomain. Here induced fit docking strategy was employed to explore the important intrinsic interactions of ligands with CREBBP bromodomain, consistently molecular dynamics simulation with two different methods and binding energy calculations by MM-GBSA and MM-PBSA were adopted to determine the stability of intermolecular interactions between protein and ligands. The results showed that both these derivatives made direct contacts with the important conserved residues of the active site, where propionylshikonin demonstrated stronger binding and stability than acetylshikonin, according to molecular dynamics simulation and binding free energy calculations. Further, QM/MM energy calculation was employed to study the chemical reactivity of the propionylshikonin and also to describe the mechanism of non bonded interactions between the propionylshikonin and CREBBP bromodomain. Though this study demands in vitro and in vivo experiments to evaluate the efficiency of the compound, these insights would assist to design more potent CREBBP bromodomain inhibitor, guiding the site of modification of propionylshikonin moiety for designing selective inhibitors. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Modulation of benzodiazepine by lysine and pipecolic acid on pentylenetetrazol-induced seizures

    International Nuclear Information System (INIS)

    Chang, Y.F.; Hargest, V.; Chen, J.S.

    1988-01-01

    L-lysine and its metabolite pipecolic acid (PA) have been studied for their effects on pentylenetetrazol (PTZ)-induced seizures in mice. L-Lysine of L-Pa i.p. significantly increased clonic and tonic latencies in a dose-dependent manner against 90 mg/kg PTZ-induced seizures. L-Lysine but not L-Pa enhanced the anticonvulsant effect of diazepam (DZ). L-Pa i.c.v. showed a slight decrease in clonic latency; it did not enhance the antiseizure activity of DZ; it caused seizures at 0.6 mmol/kg. D-PA i.c.v. displayed an opposite effect compared to its L-isomer. The anticonvulsant effect of L-lysine in terms of increase in seizure latency and survival was even more amplified when tested with a submaximal PTZ concentration. L-Lysine showed an enhancement of specific 3 H-flunitrazepam(FZ) binding to mouse brain membranes both in vitro an din vivo. The possibility of L-lysine acting as a modulator for the GABA/benzodiazepine receptors was demonstrated. Since L-PA showed enhancement of 3 H-FZ binding only in vitro but not in vivo, the anticonvulsant effect of L-PA may not be linked to the GABA/benzodiazepine receptor

  11. Lysine-Grafted MCM-41 Silica as an Antibacterial Biomaterial.

    Science.gov (United States)

    Villegas, María F; Garcia-Uriostegui, Lorena; Rodríguez, Ofelia; Izquierdo-Barba, Isabel; Salinas, Antonio J; Toriz, Guillermo; Vallet-Regí, María; Delgado, Ezequiel

    2017-09-26

    This paper proposes a facile strategy for the zwitterionization of bioceramics that is based on the direct incorporation of l-lysine amino acid via the ε-amino group onto mesoporous MCM-41 materials. Fourier transform infrared (FTIR) studies of lysine-grafted MCM-41 (MCM-LYS) simultaneously showed bands at 3080 and 1540 cm -1 and bands at 1625 and 1415 cm -1 corresponding to -NH 3+ /COO - pairs, which demonstrate the incorporation of the amino acid on the material surface keeping its zwitterionic character. Both elemental and thermogravimetric analyses showed that the amount of grafted lysine was 8 wt. % based on the bioceramic total weight. Moreover, MCM-LYS exhibited a reduction of adhesion of S. aureus and E. coli bacteria in 33% and 50%, respectively at physiological pH, as compared with pristine MCM-41. Biofilm studies onto surfaces showed that lysine functionalization elicited a reduction of the area covered by S. aureus biofilm from 42% to only 5% (88%). This research shows a simple and effective approach to chemically modify bioceramics using single amino acids that provides zwitterionic functionality, which is useful to develop new biomaterials that are able to resist bacterial adhesion.

  12. Lysine-Grafted MCM-41 Silica as an Antibacterial Biomaterial

    Directory of Open Access Journals (Sweden)

    María F. Villegas

    2017-09-01

    Full Text Available This paper proposes a facile strategy for the zwitterionization of bioceramics that is based on the direct incorporation of l-lysine amino acid via the ε-amino group onto mesoporous MCM-41 materials. Fourier transform infrared (FTIR studies of lysine-grafted MCM-41 (MCM-LYS simultaneously showed bands at 3080 and 1540 cm−1 and bands at 1625 and 1415 cm−1 corresponding to -NH3+/COO− pairs, which demonstrate the incorporation of the amino acid on the material surface keeping its zwitterionic character. Both elemental and thermogravimetric analyses showed that the amount of grafted lysine was 8 wt. % based on the bioceramic total weight. Moreover, MCM-LYS exhibited a reduction of adhesion of S. aureus and E. coli bacteria in 33% and 50%, respectively at physiological pH, as compared with pristine MCM-41. Biofilm studies onto surfaces showed that lysine functionalization elicited a reduction of the area covered by S. aureus biofilm from 42% to only 5% (88%. This research shows a simple and effective approach to chemically modify bioceramics using single amino acids that provides zwitterionic functionality, which is useful to develop new biomaterials that are able to resist bacterial adhesion.

  13. Lysine acetylation targets protein complexes and co-regulates major cellular functions

    DEFF Research Database (Denmark)

    Choudhary, Chuna Ram; Kumar, Chanchal; Gnad, Florian

    2009-01-01

    Lysine acetylation is a reversible posttranslational modification of proteins and plays a key role in regulating gene expression. Technological limitations have so far prevented a global analysis of lysine acetylation's cellular roles. We used high-resolution mass spectrometry to identify 3600......, cell cycle, splicing, nuclear transport, and actin nucleation. Acetylation impaired phosphorylation-dependent interactions of 14-3-3 and regulated the yeast cyclin-dependent kinase Cdc28. Our data demonstrate that the regulatory scope of lysine acetylation is broad and comparable with that of other...

  14. Small molecule inhibitors of bromodomain-acetyl-lysine interactions.

    Science.gov (United States)

    Brand, Michael; Measures, Angelina R; Measures, Angelina M; Wilson, Brian G; Cortopassi, Wilian A; Alexander, Rikki; Höss, Matthias; Hewings, David S; Rooney, Timothy P C; Paton, Robert S; Conway, Stuart J

    2015-01-16

    Bromodomains are protein modules that bind to acetylated lysine residues. Their interaction with histone proteins suggests that they function as "readers" of histone lysine acetylation, a component of the proposed "histone code". Bromodomain-containing proteins are often found as components of larger protein complexes with roles in fundamental cellular process including transcription. The publication of two potent ligands for the BET bromodomains in 2010 demonstrated that small molecules can inhibit the bromodomain-acetyl-lysine protein-protein interaction. These molecules display strong phenotypic effects in a number of cell lines and affect a range of cancers in vivo. This work stimulated intense interest in developing further ligands for the BET bromodomains and the design of ligands for non-BET bromodomains. Here we review the recent progress in the field with particular attention paid to ligand design, the assays employed in early ligand discovery, and the use of computational approaches to inform ligand design.

  15. Enhanced Amelioration of High-Fat Diet-Induced Fatty Liver by Docosahexaenoic Acid and Lysine Supplementations

    Directory of Open Access Journals (Sweden)

    Hsin-Yu Lin

    2014-01-01

    Full Text Available Fatty liver disease is the most common pathological condition in the liver. Here, we generated high-fat diet-(HFD- induced nonalcoholic fatty liver disease (NAFLD in mice and tested the effects of docosahexaenoic acid (DHA and lysine during a four-week regular chow (RCfeeding. Our results showed that 1% lysine and the combination of 1% lysine + 1% DHA reduced body weight. Moreover, serum triglyceride levels were reduced by 1% DHA and 1% lysine, whereas serum alanine transaminase activity was reduced by 1% DHA and 1% DHA + 0.5% lysine. Switching to RC reduced hepatic lipid droplet accumulation, which was further reduced by the addition of DHA or lysine. Furthermore, the mRNA expressions of hepatic proinflammatory cytokines were suppressed by DHA and combinations of DHA + lysine, whereas the mRNA for the lipogenic gene, acetyl-CoA carboxylase 1 (ACC1, was suppressed by DHA. In the gonadal adipose tissues, combinations of DHA and lysine inhibited mRNA expression of lipid metabolism-associated genes, including ACC1, fatty acid synthase, lipoprotein lipase, and perilipin. In conclusion, the present study demonstrated that, in conjunction with RC-induced benefits, supplementation with DHA or lysine further ameliorated the high-fat diet-induced NAFLD and provided an alternative strategy to treat, and potentially prevent, NAFLD.

  16. Surface biomimetic modification with laminin-loaded heparin/poly-L-lysine nanoparticles for improving the biocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Tao, E-mail: 11140021@hyit.edu.cn [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huai' an (China); Hu, Youdong [Department of Geriatrics, The Affiliated Huai' an Hospital of Xuzhou Medical College, Huai' an (China); Tan, Jianying [Key Lab. of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu (China); Liu, Shihui [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huai' an (China); Chen, Junying [Key Lab. of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu (China); Guo, Xin; Pan, Changjiang [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huai' an (China); Li, Xia, E-mail: xial_li@qq.com [Department of Geriatrics, The Affiliated Huai' an Hospital of Xuzhou Medical College, Huai' an (China)

    2017-02-01

    Late thrombus and restenosis caused by delayed endothelialization and insufficient biocompatibility of polymer coating continue to be the greatest limitations of drug-eluting stents. In this study, based on the specific structure of vascular basement membrane, a novel biomimetic nano-coating was constructed by incorporating laminin into electrostatic-assembled heparin/poly-L-lysine nanoparticles. Alteration of heparin and poly-L-lysine concentration ratio in a certain range has no significantly influence nanoparticle size, uniformity and stability, but may affect the chemical property and subsequently the binding efficiency to dopamine-coated titanium surface. By use of this feature, four different nanoparticles were synthesized and immobilized on titanium surface for creating gradient nanoparticle binding density. According to in vitro biocompatibility evaluation, the nanoparticle modified surfaces were found to effectively block coagulation pathway and reduce thrombosis formation. Moreover, NP10L and NP15L modified surface with relatively low heparin exposing density (4.9 to 7.1 μg/cm2) showed beneficial effect in selective promoting EPCs and ECs proliferation, as well as stimulating cell migration and NO synthesis. - Highlights: • A novel laminin-loaded anticoagulant nanoparticle was prepared and used for titanium surface modification. • The nanoparticle binding density was adjustable by alteration the concentration ratio of heparin and poly-L-lysine. • In a certain range of NPs density, the surface was found to selectively direct platelet and vascular cells behavior.

  17. Surface biomimetic modification with laminin-loaded heparin/poly-L-lysine nanoparticles for improving the biocompatibility

    International Nuclear Information System (INIS)

    Liu, Tao; Hu, Youdong; Tan, Jianying; Liu, Shihui; Chen, Junying; Guo, Xin; Pan, Changjiang; Li, Xia

    2017-01-01

    Late thrombus and restenosis caused by delayed endothelialization and insufficient biocompatibility of polymer coating continue to be the greatest limitations of drug-eluting stents. In this study, based on the specific structure of vascular basement membrane, a novel biomimetic nano-coating was constructed by incorporating laminin into electrostatic-assembled heparin/poly-L-lysine nanoparticles. Alteration of heparin and poly-L-lysine concentration ratio in a certain range has no significantly influence nanoparticle size, uniformity and stability, but may affect the chemical property and subsequently the binding efficiency to dopamine-coated titanium surface. By use of this feature, four different nanoparticles were synthesized and immobilized on titanium surface for creating gradient nanoparticle binding density. According to in vitro biocompatibility evaluation, the nanoparticle modified surfaces were found to effectively block coagulation pathway and reduce thrombosis formation. Moreover, NP10L and NP15L modified surface with relatively low heparin exposing density (4.9 to 7.1 μg/cm2) showed beneficial effect in selective promoting EPCs and ECs proliferation, as well as stimulating cell migration and NO synthesis. - Highlights: • A novel laminin-loaded anticoagulant nanoparticle was prepared and used for titanium surface modification. • The nanoparticle binding density was adjustable by alteration the concentration ratio of heparin and poly-L-lysine. • In a certain range of NPs density, the surface was found to selectively direct platelet and vascular cells behavior.

  18. Evaluation of umbilical cord mesenchymal stem cells labeling with superparamagnetic iron oxide nanoparticles coated with dextran and complexed with Poly-L-Lysine

    International Nuclear Information System (INIS)

    Sibov, Tatiana Tais; Mamani, Javier Bustamante; Pavon, Lorena Favaro; Cardenas, Walter Humberto; Gamarra, Lionel Fernel; Miyaki, Liza Aya Mabuchi; Marti, Luciana Cavalheiro; Sardinha, Luiz Roberto; Oliveira, Daniela Mara de

    2012-01-01

    Objective: The objective of this study was to evaluate the effect of the labeling of umbilical cord vein derived mesenchymal stem cells with superparamagnetic iron oxide nanoparticles coated with dextran and complexed to a non-viral transfector agent transfector poly-L-lysine. Methods: The labeling of mesenchymal stem cells was performed using the superparamagnetic iron oxide nanoparticles/dextran complexed and not complexed to poly-L-lysine. Superparamagnetic iron oxide nanoparticles/dextran was incubated with poly-L-lysine in an ultrasonic sonicator at 37 deg C for 10 minutes for complex formation superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine by electrostatic interaction. Then, the mesenchymal stem cells were incubated overnight with the complex superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine and superparamagnetic iron oxide nanoparticles/dextran. After the incubation period the mesenchymal stem cells were evaluated by internalization of the complex superparamagnetic iron oxide nanoparticles/dextran/polyL-lysine and superparamagnetic iron oxide nanoparticles/dextran by Prussian Blue stain. Cellular viability of labeled mesenchymal stem cells was evaluated by cellular proliferation assay using 5,6-carboxyfluorescein-succinimidyl ester method and apoptosis detection by Annexin V- Propidium Iodide assay. Results: mesenchymal stem cells labeled with superparamagnetic iron oxide nanoparticles/ dextran without poly-L-lysine not internalized efficiently the superparamagnetic iron oxide nanoparticles due to its low presence detected within cells. Mesenchymal stem cells labeled with the complex superparamagnetic iron oxide nanoparticles/dextran/polyL-lysine efficiently internalized the superparamagnetic iron oxide nanoparticles due to greater presence in the cells interior. The viability and apoptosis assays demonstrated that the mesenchymal stem cells labeled and not labeled respectively with the superparamagnetic iron oxide

  19. The tRNA synthetase paralog PoxA modifies elongation factor-P with (R)-ß-lysine

    DEFF Research Database (Denmark)

    Roy, Hervé; Zou, S Betty; Bullwinkle, Tammy J

    2011-01-01

    The lysyl-tRNA synthetase paralog PoxA modifies elongation factor P (EF-P) with a-lysine at low efficiency. Cell-free extracts containing non-a-lysine substrates of PoxA modified EF-P with a change in mass consistent with addition of ß-lysine, a substrate also predicted by genomic analyses. EF......-P was efficiently functionally modified with (R)-ß-lysine but not (S)-ß-lysine or genetically encoded a-amino acids, indicating that PoxA has evolved an activity orthogonal to that of the canonical aminoacyl-tRNA synthetases....

  20. Structural Basis for Recognition of L-lysine, L-ornithine, and L-2,4-diamino Butyric Acid by Lysine Cyclodeaminase.

    Science.gov (United States)

    Min, Kyungjin; Yoon, Hye-Jin; Matsuura, Atsushi; Kim, Yong Hwan; Lee, Hyung Ho

    2018-04-30

    L-pipecolic acid is a non-protein amino acid commonly found in plants, animals, and microorganisms. It is a well-known precursor to numerous microbial secondary metabolites and pharmaceuticals, including anticancer agents, immunosuppressants, and several antibiotics. Lysine cyclodeaminase (LCD) catalyzes β-deamination of L-lysine into L-pipecolic acid using β-nicotinamide adenine dinucleotide as a cofactor. Expression of a human homolog of LCD, μ-crystallin, is elevated in prostate cancer patients. To understand the structural features and catalytic mechanisms of LCD, we determined the crystal structures of Streptomyces pristinaespiralis LCD (SpLCD) in (i) a binary complex with NAD + , (ii) a ternary complex with NAD + and L-pipecolic acid, (iii) a ternary complex with NAD + and L-proline, and (iv) a ternary complex with NAD + and L-2,4-diamino butyric acid. The overall structure of SpLCD was similar to that of ornithine cyclodeaminase from Pseudomonas putida . In addition, SpLCD recognized L-lysine, L-ornithine, and L-2,4-diamino butyric acid despite differences in the active site, including differences in hydrogen bonding by Asp236, which corresponds with Asp228 from Pseudomonas putida ornithine cyclodeaminase. The substrate binding pocket of SpLCD allowed substrates smaller than lysine to bind, thus enabling binding to ornithine and L-2,4-diamino butyric acid. Our structural and biochemical data facilitate a detailed understanding of substrate and product recognition, thus providing evidence for a reaction mechanism for SpLCD. The proposed mechanism is unusual in that NAD + is initially converted into NADH and then reverted back into NAD + at a late stage of the reaction.

  1. Evaluation and Enhancement of the Oxygen Reduction Reaction Activity on Hafnium Oxide Nanoparticles Assisted by L(+)-lysine

    International Nuclear Information System (INIS)

    Chisaka, Mitsuharu; Itagaki, Noriaki

    2016-01-01

    Evaluation of the oxygen reduction reaction (ORR) on oxide compounds is difficult owing to the insulating nature of oxides. In this study, various amounts of L(+)-lysine were added to the precursor dispersion for the hydrothermal synthesis of hafnium oxide nanoparticles on reduced graphene oxide sheets (HfO_x–rGO) to coat the HfO_x catalysts with layers of carbon, thereby increasing the conductivity and number of active sites. When the mass ratio of L(+)-lysine to GO, R, was above 26, carbon layers were formed and the amount monotonically increased with increasing R, as noted by cyclic voltammogrametry. X-ray photoelectron spectroscopy and rotating disk electrode analyses revealed that pyrolysis produced ORR-active oxygen defects, whose formation was proposed to involve carbothermal reduction. When 53 ≤ R ≤ 210, HfO_x–rGO contained a similar amount of oxygen defects and ORR activity, as represented by an onset potential of 0.9 V versus the reversible hydrogen electrode in 0.1 mol dm"−"3 H_2SO_4. However, the number of active sites depended on R due to the amount of L(+)-lysine-derived carbon layers that increased both the number of active sites and resistivity towards oxygen diffusion.

  2. (R)-β-lysine-modified elongation factor P functions in translation elongation

    DEFF Research Database (Denmark)

    Bullwinkle, Tammy J; Zou, S Betty; Rajkovic, Andrei

    2013-01-01

    Post-translational modification of bacterial elongation factor P (EF-P) with (R)-β-lysine at a conserved lysine residue activates the protein in vivo and increases puromycin reactivity of the ribosome in vitro. The additional hydroxylation of EF-P at the same lysine residue by the YfcM protein has......-(β)-lysyl-EF-P showed 30% increased puromycin reactivity but no differences in dipeptide synthesis rates when compared with the β-lysylated form. Unlike disruption of the other genes required for EF-P modification, deletion of yfcM had no phenotypic consequences in Salmonella. Taken together, our findings indicate...

  3. Minoxidil specifically decreases the expression of lysine hydroxylase in cultured human skin fibroblasts.

    Science.gov (United States)

    Hautala, T; Heikkinen, J; Kivirikko, K I; Myllylä, R

    1992-01-01

    The levels of lysine hydroxylase protein and the levels of the mRNAs for lysine hydroxylase and the alpha- and beta-subunits of proline 4-hydroxylase were measured in cultured human skin fibroblasts treated with 1 mM-minoxidil. The data demonstrate that minoxidil decreases the amount of lysine hydroxylase protein, this being due to a decrease in the level of lysine hydroxylase mRNA. The effect of minoxidil appears to be highly specific, as no changes were observed in the amounts of mRNAs for the alpha- and beta-subunits of proline 4-hydroxylase. Images Fig. 1. Fig. 2. Fig. 3. PMID:1314568

  4. Selection and Characterization of a Lysine Yielding Mutant of Corynebacterium glutamicum - a Soil Isolate from Pakistan

    Directory of Open Access Journals (Sweden)

    Habib-ur-Rehman§٭, Abdul Hameed and Safia Ahmed

    2012-01-01

    Full Text Available L-lysine is the second limiting amino acid for poultry and supplemented in broiler feed for optimal performance. Lysine can be produced by inducing mutation in glutamate producing bacteria. The study was conducted to enhance lysine production from a local strain of Corynebacterium glutamicum. The bacterium was mutated by exposure to UV. Mutants resistant to s-2-aminoethyle L-cystein (AEC and showing auxotrophy for L-homoserine were screened for lysine production qualitatively and quantitatively. A mutant showing highest production of lysine (8.2 mg/mL was selected for optimization of physical and nutritional parameters for maximum production of lysine in shake flask. An initial pH 7.6, 30˚C temperature, 300 rpm and 60 h incubation time were the optimized values of physical requirements. Cane molasses and corn starch hydrolysate were required at 15% (w/v in the fermentation media which provided around 9% total sugars to produce maximum lysine (17 to 18 mg/mL. When amonium sulphate was used at 3.5% (w/v level in molasses or corn starch hydrolysate based fermentation media, production of lysine slightly increased above 18 mg/mL. It is concluded that industrial by products like cane molasses, corn steep liquor, and corn starch hydrolysate can be used as carbon and organic nitrogen sources in fermentation medium for scale up process of lysine production and this lysine enriched broth may be used in broiler feed later. However, more potent lysine producing mutant and additional in vivo trials would be required to commercialize this product.

  5. Lysine clonixinate versus dipyrone (metamizole) for the acute treatment of severe migraine attacks: a single-blind, randomized study

    OpenAIRE

    Krymchantowski,Abouch Valenty; Carneiro,Henrique; Barbosa,Jackeline; Jevoux,Carla

    2008-01-01

    BACKGROUND AND OBJECTIVE: Nonsteroidal anti-inflammatory drugs (NSAID) are effective to treat migraine attacks. Lysine clonixinate (LC) and dipyrone (metamizol) have been proven effective to treat acute migraine. The aim of this study was to evaluate the efficacy and tolerability of the intravenous formulations of LC and dipyrone in the treatment of severe migraine attacks. METHOD: Thirty patients (28 women, 2 men), aged 18 to 48 years with migraine according the International Headache Societ...

  6. Chitosan and Its Derivatives for Application in Mucoadhesive Drug Delivery Systems

    Directory of Open Access Journals (Sweden)

    Twana Mohammed M. Ways

    2018-03-01

    Full Text Available Mucoadhesive drug delivery systems are desirable as they can increase the residence time of drugs at the site of absorption/action, provide sustained drug release and minimize the degradation of drugs in various body sites. Chitosan is a cationic polysaccharide that exhibits mucoadhesive properties and it has been widely used in the design of mucoadhesive dosage forms. However, its limited mucoadhesive strength and limited water-solubility at neutral and basic pHs are considered as two major drawbacks of its use. Chemical modification of chitosan has been exploited to tackle these two issues. In this review, we highlight the up-to-date studies involving the synthetic approaches and description of mucoadhesive properties of chitosan and chitosan derivatives. These derivatives include trimethyl chitosan, carboxymethyl chitosan, thiolated chitosan, chitosan-enzyme inhibitors, chitosan-ethylenediaminetetraacetic acid (chitosan-EDTA, half-acetylated chitosan, acrylated chitosan, glycol chitosan, chitosan-catechol, methyl pyrrolidinone-chitosan, cyclodextrin-chitosan and oleoyl-quaternised chitosan. We have particularly focused on the effect of chemical derivatization on the mucoadhesive properties of chitosan. Additionally, other important properties including water-solubility, stability, controlled release, permeation enhancing effect, and in vivo performance are also described.

  7. Detection of DNA and poly-l-lysine using CVD graphene-channel FET biosensors

    International Nuclear Information System (INIS)

    Kakatkar, Aniket; Craighead, H G; Abhilash, T S; Alba, R De; Parpia, J M

    2015-01-01

    A graphene channel field-effect biosensor is demonstrated for detecting the binding of double-stranded DNA and poly-l-lysine. Sensors consist of chemical vapor deposition graphene transferred using a clean, etchant-free transfer method. The presence of DNA and poly-l-lysine are detected by the conductance change of the graphene transistor. A readily measured shift in the Dirac voltage (the voltage at which the graphene’s resistance peaks) is observed after the graphene channel is exposed to solutions containing DNA or poly-l-lysine. The ‘Dirac voltage shift’ is attributed to the binding/unbinding of charged molecules on the graphene surface. The polarity of the response changes to positive direction with poly-l-lysine and negative direction with DNA. This response results in detection limits of 8 pM for 48.5 kbp DNA and 11 pM for poly-l-lysine. The biosensors are easy to fabricate, reusable and are promising as sensors of a wide variety of charged biomolecules. (paper)

  8. Extensive Lysine Methylation in Hyperthermophilic Crenarchaea: Potential Implications for Protein Stability and Recombinant Enzymes

    Directory of Open Access Journals (Sweden)

    Catherine H. Botting

    2010-01-01

    Full Text Available In eukarya and bacteria, lysine methylation is relatively rare and is catalysed by sequence-specific lysine methyltransferases that typically have only a single-protein target. Using RNA polymerase purified from the thermophilic crenarchaeum Sulfolobus solfataricus, we identified 21 methyllysines distributed across 9 subunits of the enzyme. The modified lysines were predominantly in α-helices and showed no conserved sequence context. A limited survey of the Thermoproteus tenax proteome revealed widespread modification with 52 methyllysines in 30 different proteins. These observations suggest the presence of an unusual lysine methyltransferase with relaxed specificity in the crenarchaea. Since lysine methylation is known to enhance protein thermostability, this may be an adaptation to a thermophilic lifestyle. The implications of this modification for studies and applications of recombinant crenarchaeal enzymes are discussed.

  9. The effect of gamma irradiation on the lysine content of plants

    International Nuclear Information System (INIS)

    Benedekne-Lazar, M.

    1979-01-01

    It has been proved by studies on the physiological effect of ionizing irradiation that in plant metabolism important changes take place. From the endosperm of seven-day-old seedlings 14 C-L-Lysine is transported faster to organs, especially to shoots and its incorporation into protein is also more intensive. The animation of the growth of roots and shoots can be observed on 14-day-old plants grown in water culture. In sand culture a surplus in dry weight can be experienced after 56 days for maize, under the influence of 100 rad. Two soybean varieties (Merit, Clay) responded different to irradiation. The dry weight of the Merit variety was increased significantly by 500 and 1000 rad, whereas that of the Clay variety decreased or did not change significantly. The lysine content of plants changes in the function of growth. In the case of the two maize varieties (Szegedi sarga, KSC 360) treatments with 1000 and 5000 rad resulted in an essential surplus of the total lysine content (46.25 and 31.21%, respectively). The total lysine content of the Merit variety has been increased by about 23.9% and 20.92%, respectively. 5000 rad treatment resulted in a negative correlation (-0.77) in the shoots. The total lysine content of the Clay plants was lower than that of the control. Under the influence of 500 and 1000 rad treatments the total lysine content of the shoots of the Merit variety grown in fields increased to a lesser extent (16.82 and 3.19 respectively) than that of plants grown in a climate room. (author)

  10. The biology of lysine acetylation integrates transcriptional programming and metabolism

    Directory of Open Access Journals (Sweden)

    Mujtaba Shiraz

    2011-03-01

    Full Text Available Abstract The biochemical landscape of lysine acetylation has expanded from a small number of proteins in the nucleus to a multitude of proteins in the cytoplasm. Since the first report confirming acetylation of the tumor suppressor protein p53 by a lysine acetyltransferase (KAT, there has been a surge in the identification of new, non-histone targets of KATs. Added to the known substrates of KATs are metabolic enzymes, cytoskeletal proteins, molecular chaperones, ribosomal proteins and nuclear import factors. Emerging studies demonstrate that no fewer than 2000 proteins in any particular cell type may undergo lysine acetylation. As described in this review, our analyses of cellular acetylated proteins using DAVID 6.7 bioinformatics resources have facilitated organization of acetylated proteins into functional clusters integral to cell signaling, the stress response, proteolysis, apoptosis, metabolism, and neuronal development. In addition, these clusters also depict association of acetylated proteins with human diseases. These findings not only support lysine acetylation as a widespread cellular phenomenon, but also impel questions to clarify the underlying molecular and cellular mechanisms governing target selectivity by KATs. Present challenges are to understand the molecular basis for the overlapping roles of KAT-containing co-activators, to differentiate between global versus dynamic acetylation marks, and to elucidate the physiological roles of acetylated proteins in biochemical pathways. In addition to discussing the cellular 'acetylome', a focus of this work is to present the widespread and dynamic nature of lysine acetylation and highlight the nexus that exists between epigenetic-directed transcriptional regulation and metabolism.

  11. Estimation of Digestible Lysine Requirements of Japanese Quail during the Starter Period

    Directory of Open Access Journals (Sweden)

    M Ashoori

    2013-11-01

    Full Text Available The aim of this study was the estimation of digestible lysine requirements of Japanese quail during the 7-21d period. Graduation level of L-lysine.HCL were added to the basal diet at the expense of corn starch to create different levels of digestible lysine ranged from 0.75 to 1.35% of diet. Growth performance and carcass composition were evaluated during the experiment. The results showed that incremental levels of digestible lysine significantly affected the body weight gain (BWG, feed conversion ratio (FCR, feed intake (FI, breast meat yield (BMY and thigh meat yield (TMY. Either linear broken- line or quadratic broken line model were used to get break points of digestible lysine as a requirement. Based on linear broken line analysis, the break points for FCR and BMY were 0.99 and 1.04 % of diet, respectively. Using the quadratic broken-line model, the estimated Lys requirements for BWG, FCR, and BMY were 1.11, 1.04, and 1.15% of diet, respectively. The results showed that the Lys needs for optimum BMY was higher than BWG and FCR.

  12. Maternal malaria induces a procoagulant and antifibrinolytic state that is embryotoxic but responsive to anticoagulant therapy.

    Directory of Open Access Journals (Sweden)

    John W Avery

    Full Text Available Low birth weight and fetal loss are commonly attributed to malaria in endemic areas, but the cellular and molecular mechanisms that underlie these poor birth outcomes are incompletely understood. Increasing evidence suggests that dysregulated hemostasis is important in malaria pathogenesis, but its role in placental malaria (PM, characterized by intervillous sequestration of Plasmodium falciparum, proinflammatory responses, and excessive fibrin deposition is not known. To address this question, markers of coagulation and fibrinolysis were assessed in placentae from malaria-exposed primigravid women. PM was associated with significantly elevated placental monocyte and proinflammatory marker levels, enhanced perivillous fibrin deposition, and increased markers of activated coagulation and suppressed fibrinolysis in placental plasma. Submicroscopic PM was not proinflammatory but tended to be procoagulant and antifibrinolytic. Birth weight trended downward in association with placental parasitemia and high fibrin score. To directly assess the importance of coagulation in malaria-induced compromise of pregnancy, Plasmodium chabaudi AS-infected pregnant C57BL/6 mice were treated with the anticoagulant, low molecular weight heparin. Treatment rescued pregnancy at midgestation, with substantially decreased rates of active abortion and reduced placental and embryonic hemorrhage and necrosis relative to untreated animals. Together, the results suggest that dysregulated hemostasis may represent a novel therapeutic target in malaria-compromised pregnancies.

  13. Synthesis and Phase Behavior of Poly(N-isopropylacrylamide-b- Poly(L-Lysine Hydrochloride and Poly(N-Isopropylacrylamide- co-Acrylamide-b-Poly(L-Lysine Hydrochloride

    Directory of Open Access Journals (Sweden)

    Milica Spasojević

    2014-07-01

    Full Text Available The synthesis of poly(N-isopropylacrylamide-b-poly(L-lysine and poly(N- isopropylacrylamide-co-acrylamide-b-poly(L-lysine copolymers was accomplished by combining atom transfer radical polymerization (ATRP and ring opening polymerization (ROP. For this purpose, a di-functional initiator with protected amino group was successfully synthetized. The ATRP of N-isopropylacrylamide yielded narrowly dispersed polymers with consistent high yields (~80%. Lower yields (~50% were observed when narrowly dispersed random copolymers of N-isopropylacrylamide and acrylamide where synthesized. Amino-terminated poly(N-isopropylacrylamide and poly(N-isopropylacrylamide- co-acrylamide were successfully used as macroinitiators for ROP of N6-carbobenzoxy-L- lysine N-carboxyanhydride. The thermal behavior of the homopolymers and copolymers in aqueous solutions was studied by turbidimetry, dynamic light scattering (DLS and proton nuclear magnetic resonance spectroscopy (1H-NMR.

  14. Lysine Rich Proteins in the Salt-Soluble Protein Fraction of Barley

    DEFF Research Database (Denmark)

    Ingversen, J.; Køie, B.

    1973-01-01

    Fractionation of the protein complex from Emir barley showed that the salt-soluble fraction accounts for 44% of the total lysine content but only for 2.......Fractionation of the protein complex from Emir barley showed that the salt-soluble fraction accounts for 44% of the total lysine content but only for 2....

  15. Lysine Deacetylases and Regulated Glycolysis in Macrophages.

    Science.gov (United States)

    Shakespear, Melanie R; Iyer, Abishek; Cheng, Catherine Youting; Das Gupta, Kaustav; Singhal, Amit; Fairlie, David P; Sweet, Matthew J

    2018-06-01

    Regulated cellular metabolism has emerged as a fundamental process controlling macrophage functions, but there is still much to uncover about the precise signaling mechanisms involved. Lysine acetylation regulates the activity, stability, and/or localization of metabolic enzymes, as well as inflammatory responses, in macrophages. Two protein families, the classical zinc-dependent histone deacetylases (HDACs) and the NAD-dependent HDACs (sirtuins, SIRTs), mediate lysine deacetylation. We describe here mechanisms by which classical HDACs and SIRTs directly regulate specific glycolytic enzymes, as well as evidence that links these protein deacetylases to the regulation of glycolysis-related genes. In these contexts, we discuss HDACs and SIRTs as key control points for regulating immunometabolism and inflammatory outputs from macrophages. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Nε-(carboxymethyl)lysine and Nε-(carboxyethyl)lysine in tea and the factors affecting their formation.

    Science.gov (United States)

    Jiao, Ye; He, Jialiang; Li, Fengli; Tao, Guanjun; Zhang, Shuang; Zhang, Shikang; Qin, Fang; Zeng, Maomao; Chen, Jie

    2017-10-01

    The levels of N ε -(carboxymethyl)lysine (CML) and N ε -(carboxyethyl)lysine (CEL) in 99 tea samples from 14 geographic regions, including 44 green, 7 oolong, 41 black, and 7 dark teas were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The CML and CEL contents varied from 11.0 to 1701μg/g tea and 4.6 to 133μg/g tea, respectively. Dark tea presented the highest levels of CML and CEL, whereas green and oolong teas presented the lowest levels. Five kinds of catechins in the tea were also analyzed, and spearman's correlation coefficients showed that all the catechins negatively correlated with CML and CEL. The results suggested that withering, fermentation and pile fermentation may facilitate the formation of CML and CEL. Catechins might inhibit the formation of CML and CEL, but their inhibitory effects may be affected by tea processing. The results of this study are useful for the production of healthier tea. Copyright © 2017. Published by Elsevier Ltd.

  17. Flux through the tetrahydrodipicolinate succinylase pathway is dispensable for L-lysine production in Corynebacterium glutamicum.

    Science.gov (United States)

    Shaw-Reid, C A; McCormick, M M; Sinskey, A J; Stephanopoulos, G

    1999-03-01

    The N-succinyl-LL-diaminopimelate desuccinylase gene (dapE) in the four-step succinylase branch of the L-lysine biosynthetic pathway of Corynebacterium glutamicum was disrupted via marker-exchange mutagenesis to create a mutant strain that uses only the one-step meso-diaminopimelate dehydrogenase branch to overproduce lysine. This mutant strain grew and utilized glucose from minimal medium at the same rate as the parental strain. In addition, the dapE- strain produced lysine at the same rate as its parent strain. Transformation of the parental and dapE- strains with the amplified meso-diaminopimelate dehydrogenase gene (ddh) on a plasmid did not affect lysine production in either strain, despite an eightfold amplification of the activity of the enzyme. These results indicate that the four-step succinylase pathway is dispensable for lysine overproduction in shake-flask culture. In addition, the one-step meso-diaminopimelate dehydrogenase pathway does not limit lysine flux in Corynebacterium under these conditions.

  18. Molecular dynamics simulation of coarse-grained poly(L-lysine) dendrimers.

    Science.gov (United States)

    Rahimi, Ali; Amjad-Iranagh, Sepideh; Modarress, Hamid

    2016-03-01

    Poly(L-lysine) (PLL) dendrimer are amino acid based macromolecules and can be used as drug delivery agents. Their branched structure allows them to be functionalized by various groups to encapsulate drug agents into their structure. In this work, at first, an attempt was made on all-atom simulation of PLL dendrimer of different generations. Based on all-atom results, a course-grained model of this dendrimer was designed and its parameters were determined, to be used for simulation of three generations of PLL dendrimer, at two pHs. Similar to the all-atom, the coarse-grained results indicated that by increasing the generation, the dendrimer becomes more spherical. At pH 7, the dendrimer had larger size, whereas at pH 12, due to back folding of branching chains, they had the tendency to penetrate into the inner layers. The calculated radial probability and radial distribution functions confirm that at pH 7, the PLL dendrimer has more cavities and as a result it can encapsulate more water molecules into its inner structure. By calculating the moment of inertia and the aspect ratio, the formation of spherical structure for PLL dendrimer was confirmed.

  19. Design of Chitosan and Its Water Soluble Derivatives-Based Drug Carriers with Polyelectrolyte Complexes

    Directory of Open Access Journals (Sweden)

    Qing-Xi Wu

    2014-12-01

    Full Text Available Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have been considered well-suited as biomaterials for a number of vital drug carriers with targeted/controlled release profiles, e.g., films, capsules, microcapsules. In this work, an overview highlights not only the favorable properties of chitosan and its water soluble derivatives but also the good performance of the polyelectrolyte complexes produced based on chitosan. Their various types of applications as drug carriers are reviewed in detail.

  20. Design of chitosan and its water soluble derivatives-based drug carriers with polyelectrolyte complexes.

    Science.gov (United States)

    Wu, Qing-Xi; Lin, Dong-Qiang; Yao, Shan-Jing

    2014-12-19

    Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have been considered well-suited as biomaterials for a number of vital drug carriers with targeted/controlled release profiles, e.g., films, capsules, microcapsules. In this work, an overview highlights not only the favorable properties of chitosan and its water soluble derivatives but also the good performance of the polyelectrolyte complexes produced based on chitosan. Their various types of applications as drug carriers are reviewed in detail.

  1. Design of Chitosan and Its Water Soluble Derivatives-Based Drug Carriers with Polyelectrolyte Complexes

    Science.gov (United States)

    Wu, Qing-Xi; Lin, Dong-Qiang; Yao, Shan-Jing

    2014-01-01

    Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have been considered well-suited as biomaterials for a number of vital drug carriers with targeted/controlled release profiles, e.g., films, capsules, microcapsules. In this work, an overview highlights not only the favorable properties of chitosan and its water soluble derivatives but also the good performance of the polyelectrolyte complexes produced based on chitosan. Their various types of applications as drug carriers are reviewed in detail. PMID:25532565

  2. Systematic Analysis of the Functions of Lysine Acetylation in the Regulation of Tat Activity.

    Directory of Open Access Journals (Sweden)

    Minghao He

    Full Text Available The Tat protein of HIV-1 has several well-known properties, such as nucleocytoplasmic trafficking, transactivation of transcription, interaction with tubulin, regulation of mitotic progression, and induction of apoptosis. Previous studies have identified a couple of lysine residues in Tat that are essential for its functions. In order to analyze the functions of all the lysine residues in Tat, we mutated them individually to alanine, glutamine, and arginine. Through systematic analysis of the lysine mutants, we discovered several previously unidentified characteristics of Tat. We found that lysine acetylation could modulate the subcellular localization of Tat, in addition to the regulation of its transactivation activity. Our data also revealed that lysine mutations had distinct effects on microtubule assembly and Tat binding to bromodomain proteins. By correlation analysis, we further found that the effects of Tat on apoptosis and mitotic progression were not entirely attributed to its effect on microtubule assembly. Our findings suggest that Tat may regulate diverse cellular activities through binding to different proteins and that the acetylation of distinct lysine residues in Tat may modulate its interaction with various partners.

  3. Self-degradation of tissue adhesive based on oxidized dextran and poly-L-lysine.

    Science.gov (United States)

    Matsumura, Kazuaki; Nakajima, Naoki; Sugai, Hajime; Hyon, Suong-Hyu

    2014-11-26

    We have developed a low-toxicity bioadhesive based on oxidized dextran and poly-L-lysine. Here, we report that the mechanical properties and degradation of this novel hydrogel bioadhesive can be controlled by changing the extent of oxidation of the dextran and the type or concentration of the anhydride species in the acylated poly-L-lysine. The dynamic moduli of the hydrogels can be controlled from 120 Pa to 20 kPa, suggesting that they would have mechanical compatibility with various tissues, and could have applications as tissue adhesives. Development of the hydrogel color from clear to brown indicates that the reaction between the dextran aldehyde groups and the poly-L-lysine amino groups may be induced by a Maillard reaction via Schiff base formation. Degradation of the aldehyde dextran may begin by reaction of the amino groups in the poly-L-lysine. The gel degradation can be ascribed to degradation of the aldehyde dextran in the hydrogel, although the aldehyde dextran itself is relatively stable in water. The oxidized dextran and poly-L-lysine, and the degraded hydrogel showed low cytotoxicities. These findings indicate that a hydrogel consisting of oxidized dextran and poly-L-lysine has low toxicity and a well-controlled degradation rate, and has potential clinical applications as a bioadhesive. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. The Preventive Effect of L-Lysine on Lysozyme Glycation in Type 2 Diabetes

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    Hossein Mirmiranpour

    2016-01-01

    Full Text Available Lysozyme is a bactericidal enzyme whose structure and functions change in diabetes. Chemical chaperones are small molecules including polyamines (e.g. spermine, amino acids (e.g. L-lysine and polyols (e.g. glycerol. They can improve protein conformation in several stressful conditions such as glycation. In this study, the authors aimed to observe the effect of L-lysine as a chemical chaperone on structure and function of glycated lysozyme. In this study, in vitro and in vivo effects of L-lysine on lysozyme glycation were investigated. Lysozyme was incubated with glucose and/or L-lysine, followed by an investigation of its structure by electrophoresis, fluorescence spectroscopy, and circular dichroism spectroscopy and also assessment of its bactericidal activity against M. lysodeikticus. In the clinical trial, patients with type 2 diabetes mellitus (T2DM were randomly divided into two groups of 25 (test and control. All patients received metformin and glibenclamide for a three months period. The test group was supplemented with 3 g/day of L-lysine. The quantity and activity of lysozyme and other parameters were then measured. Among the test group, L-lysine was found to reduce the advanced glycation end products (AGEs in the sera of patients with T2DM and in vitro condition. This chemical chaperone reversed the alteration in lysozyme structure and function due to glycation and resulted in increased lysozyme activity. Structure and function of glycated lysozyme are significantly improved by l-lysine; therefore it can be considered an effective therapeutic supplementation in T2DM, decreasing the risk of infection in these patients.

  5. Aflatoxin B1-lysine adduct in dried blood spot samples of animals and humans.

    Science.gov (United States)

    Xue, Kathy S; Cai, Wenjie; Tang, Lili; Wang, Jia-Sheng

    2016-12-01

    Dried blood spots (DBS) were proposed as potentially viable method for exposure assessment of environmental toxicants in infant and young children. For this study, we validated an experimental protocol to quantify AFB 1 -lysine adduct in DBS samples of AFB 1 -treated F344 rats, as well as samples from human field study. Significant dose-response relationships in AFB 1 -lysine adduct formation were found in DBS samples of rats treated with single- and repeated-dose AFB 1 . AFB 1 -lysine levels in DBS samples were highly correlated with corresponding serum sample levels. The Person coefficients were 0.997 for the single-dose exposure, and 0.996 for the repeated-dose exposure. Levels of AFB 1 -lysine adduct had also good agreement between DBS and serum samples as shown by Bland-Altman plot analysis. For human field study samples (n = 36), a Pearson correlation coefficient of 0.784 was found between AFB 1 -lysine adduct levels of DBS and corresponding serum samples. Bland-Altman plots showed the distribution of the log differences between DBS and serum AFB 1 -lysine levels are within 95% confidence intervals. These results showed AFB 1 -lysine adduct levels in DBS cards and serum samples from animals and human samples are comparable, and the DBS technique and analytical protocol is a good means to assess AFB 1 exposure in infant and children populations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Voluntary wheel running is beneficial to the amino acid profile of lysine-deficient rats.

    Science.gov (United States)

    Nagao, Kenji; Bannai, Makoto; Seki, Shinobu; Kawai, Nobuhiro; Mori, Masato; Takahashi, Michio

    2010-06-01

    Rats voluntarily run up to a dozen kilometers per night when their cages are equipped with a running wheel. Daily voluntary running is generally thought to enhance protein turnover. Thus, we sought to determine whether running worsens or improves protein degradation caused by a lysine-deficient diet and whether it changes the utilization of free amino acids released by proteolysis. Rats were fed a lysine-deficient diet and were given free access to a running wheel or remained sedentary (control) for 4 wk. Amino acid levels in plasma, muscle, and liver were measured together with plasma insulin levels and tissue weight. The lysine-deficient diet induced anorexia, skeletal muscle loss, and serine and threonine aminoacidemia, and it depleted plasma insulin and essential amino acids in skeletal muscle. Allowing rats to run voluntarily improved these symptoms; thus, voluntary wheel running made the rats less susceptible to dietary lysine deficiency. Amelioration of the declines in muscular leucine and plasma insulin observed in running rats could contribute to protein synthesis together with the enhanced availability of lysine and other essential amino acids in skeletal muscle. These results indicate that voluntary wheel running under lysine-deficient conditions does not enhance protein catabolism; on the contrary, it accelerates protein synthesis and contributes to the maintenance of muscle mass. The intense nocturnal voluntary running that characterizes rodents might be an adaptation of lysine-deficient grain eaters that allows them to maximize opportunities for food acquisition.

  7. Induced pluripotent stem cell-derived cardiomyocytes for cardiovascular disease modeling and drug screening.

    Science.gov (United States)

    Sharma, Arun; Wu, Joseph C; Wu, Sean M

    2013-12-24

    Human induced pluripotent stem cells (hiPSCs) have emerged as a novel tool for drug discovery and therapy in cardiovascular medicine. hiPSCs are functionally similar to human embryonic stem cells (hESCs) and can be derived autologously without the ethical challenges associated with hESCs. Given the limited regenerative capacity of the human heart following myocardial injury, cardiomyocytes derived from hiPSCs (hiPSC-CMs) have garnered significant attention from basic and translational scientists as a promising cell source for replacement therapy. However, ongoing issues such as cell immaturity, scale of production, inter-line variability, and cell purity will need to be resolved before human clinical trials can begin. Meanwhile, the use of hiPSCs to explore cellular mechanisms of cardiovascular diseases in vitro has proven to be extremely valuable. For example, hiPSC-CMs have been shown to recapitulate disease phenotypes from patients with monogenic cardiovascular disorders. Furthermore, patient-derived hiPSC-CMs are now providing new insights regarding drug efficacy and toxicity. This review will highlight recent advances in utilizing hiPSC-CMs for cardiac disease modeling in vitro and as a platform for drug validation. The advantages and disadvantages of using hiPSC-CMs for drug screening purposes will be explored as well.

  8. Systematic derivation of an Australian standard for Tall Man lettering to distinguish similar drug names.

    Science.gov (United States)

    Emmerton, Lynne; Rizk, Mariam F S; Bedford, Graham; Lalor, Daniel

    2015-02-01

    Confusion between similar drug names can cause harmful medication errors. Similar drug names can be visually differentiated using a typographical technique known as Tall Man lettering. While international conventions exist to derive Tall Man representation for drug names, there has been no national standard developed in Australia. This paper describes the derivation of a risk-based, standardized approach for use of Tall Man lettering in Australia, and known as National Tall Man Lettering. A three-stage approach was applied. An Australian list of similar drug names was systematically compiled from the literature and clinical error reports. Secondly, drug name pairs were prioritized using a risk matrix based on the likelihood of name confusion (a four-component score) vs. consensus ratings of the potential severity of the confusion by 31 expert reviewers. The mid-type Tall Man convention was then applied to derive the typography for the highest priority drug pair names. Of 250 pairs of confusable Australian drug names, comprising 341 discrete names, 35 pairs were identified by the matrix as an 'extreme' risk if confused. The mid-type Tall Man convention was successfully applied to the majority of the prioritized drugs; some adaption of the convention was required. This systematic process for identification of confusable drug names and associated risk, followed by application of a convention for Tall Man lettering, has produced a standard now endorsed for use in clinical settings in Australia. Periodic updating is recommended to accommodate new drug names and error reports. © 2014 John Wiley & Sons, Ltd.

  9. Tuning a Protein-Labeling Reaction to Achieve Highly Site Selective Lysine Conjugation.

    Science.gov (United States)

    Pham, Grace H; Ou, Weijia; Bursulaya, Badry; DiDonato, Michael; Herath, Ananda; Jin, Yunho; Hao, Xueshi; Loren, Jon; Spraggon, Glen; Brock, Ansgar; Uno, Tetsuo; Geierstanger, Bernhard H; Cellitti, Susan E

    2018-04-16

    Activated esters are widely used to label proteins at lysine side chains and N termini. These reagents are useful for labeling virtually any protein, but robust reactivity toward primary amines generally precludes site-selective modification. In a unique case, fluorophenyl esters are shown to preferentially label human kappa antibodies at a single lysine (Lys188) within the light-chain constant domain. Neighboring residues His189 and Asp151 contribute to the accelerated rate of labeling at Lys188 relative to the ≈40 other lysine sites. Enriched Lys188 labeling can be enhanced from 50-70 % to >95 % by any of these approaches: lowering reaction temperature, applying flow chemistry, or mutagenesis of specific residues in the surrounding protein environment. Our results demonstrated that activated esters with fluoro-substituted aromatic leaving groups, including a fluoronaphthyl ester, can be generally useful reagents for site-selective lysine labeling of antibodies and other immunoglobulin-type proteins. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Histone Lysine Methylation and Neurodevelopmental Disorders

    Directory of Open Access Journals (Sweden)

    Jeong-Hoon Kim

    2017-06-01

    Full Text Available Methylation of several lysine residues of histones is a crucial mechanism for relatively long-term regulation of genomic activity. Recent molecular biological studies have demonstrated that the function of histone methylation is more diverse and complex than previously thought. Moreover, studies using newly available genomics techniques, such as exome sequencing, have identified an increasing number of histone lysine methylation-related genes as intellectual disability-associated genes, which highlights the importance of accurate control of histone methylation during neurogenesis. However, given the functional diversity and complexity of histone methylation within the cell, the study of the molecular basis of histone methylation-related neurodevelopmental disorders is currently still in its infancy. Here, we review the latest studies that revealed the pathological implications of alterations in histone methylation status in the context of various neurodevelopmental disorders and propose possible therapeutic application of epigenetic compounds regulating histone methylation status for the treatment of these diseases.

  11. Purification and properties of fructosyl lysine oxidase from Fusarium oxysporum S-1F4.

    Science.gov (United States)

    Sakai, Y; Yoshida, N; Isogai, A; Tani, Y; Kato, N

    1995-03-01

    Fructosyl lysine oxidase (FLOD) was examined for its use in the enzymatic measurement of the level of glycated albumin in blood serum. To isolate microorganisms having such an enzyme activity, we used N epsilon-fructosyl N alpha-Z-lysine (epsilon-FL) as a sole nitrogen source in the enrichment culture medium. The isolated fungus, strain S-1F4, showed a high FLOD activity in the cell-free extract and was identified as Fusarium oxysporum. FLOD was purified to an apparent homogeneity on SDS-PAGE. The molecular mass of the subunit was 50 kDa on SDS-PAGE and seemed to exist in a monomeric form. The enzyme had an absorption spectrum characteristic of a flavoprotein and the flavin was found to be covalently bound to the enzyme. The enzyme acted against N epsilon-fructosyl N alpha-Z-lysine and N alpha-fructosyl N epsilon-Z-lysine and showed specificity for fructosyl lysine residues.

  12. Characterisation of the first enzymes committed to lysine biosynthesis in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Michael D W Griffin

    Full Text Available In plants, the lysine biosynthetic pathway is an attractive target for both the development of herbicides and increasing the nutritional value of crops given that lysine is a limiting amino acid in cereals. Dihydrodipicolinate synthase (DHDPS and dihydrodipicolinate reductase (DHDPR catalyse the first two committed steps of lysine biosynthesis. Here, we carry out for the first time a comprehensive characterisation of the structure and activity of both DHDPS and DHDPR from Arabidopsis thaliana. The A. thaliana DHDPS enzyme (At-DHDPS2 has similar activity to the bacterial form of the enzyme, but is more strongly allosterically inhibited by (S-lysine. Structural studies of At-DHDPS2 show (S-lysine bound at a cleft between two monomers, highlighting the allosteric site; however, unlike previous studies, binding is not accompanied by conformational changes, suggesting that binding may cause changes in protein dynamics rather than large conformation changes. DHDPR from A. thaliana (At-DHDPR2 has similar specificity for both NADH and NADPH during catalysis, and has tighter binding of substrate than has previously been reported. While all known bacterial DHDPR enzymes have a tetrameric structure, analytical ultracentrifugation, and scattering data unequivocally show that At-DHDPR2 exists as a dimer in solution. The exact arrangement of the dimeric protein is as yet unknown, but ab initio modelling of x-ray scattering data is consistent with an elongated structure in solution, which does not correspond to any of the possible dimeric pairings observed in the X-ray crystal structure of DHDPR from other organisms. This increased knowledge of the structure and function of plant lysine biosynthetic enzymes will aid future work aimed at improving primary production.

  13. Radioactive Lysine in Protein Metabolism Studies

    Science.gov (United States)

    Miller, L. L.; Bale, W. F.; Yuile, C. L.; Masters, R. E.; Tishkoff, G. H.; Whipple,, G. H.

    1950-01-09

    Studies of incorporation of DL-lysine in various body proteins of the dog; the time course of labeled blood proteins; and apparent rate of disappearance of labeled plasma proteins for comparison of behavior of the plasma albumin and globulin fractions; shows more rapid turn over of globulin fraction.

  14. Extraction and LC determination of lysine clonixinate salt in water/oil microemulsions.

    Science.gov (United States)

    Pineros, I; Ballesteros, P; Lastres, J L

    2002-02-01

    A new reversed-phase high performance liquid chromatography method has been developed and validated for the quantitative determination of lysine clonixinate salt in water/oil microemulsions. The mobile phase was acetonitrile-buffer phosphate pH 3.3. Detection was UV absorbance at 252 nm. The precision and accurately of the method were excellent. The established linearity range was 5-60 microg ml(-1) (r(2)=0.999). Microemulsions samples were dispersed with chloroform and extracted lysine clonixinate salt with water. This easy method employing chloroformic extraction has been done three times. The recovery of lysine clonixinate salt from spiked placebo and microemulsion were >90% over the linear range.

  15. Insight into the collagen assembly in the presence of lysine and glutamic acid: An in vitro study

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xinhua; Dan, Nianhua [Key Laboratory for Leather Chemistry and Engineering of the Education Ministry, Sichuan University, Chengdu, Sichuan 610065 (China); Research Center of Biomedical Engineering, Sichuan University, Chengdu, Sichuan 610065 (China); Dan, Weihua, E-mail: danweihua_scu@126.com [Key Laboratory for Leather Chemistry and Engineering of the Education Ministry, Sichuan University, Chengdu, Sichuan 610065 (China); Research Center of Biomedical Engineering, Sichuan University, Chengdu, Sichuan 610065 (China)

    2017-01-01

    The aim of this study is to evaluate the effects of two different charged amino acids in collagen chains, lysine and glutamic acid, on the fibrillogenesis process of collagen molecules. The turbidity, zeta potential, and fiber diameter analysis suggest that introducing the positively charged lysine into collagen might improve the sizes or amounts of the self-assembled collagen fibrils significantly. Conversely, the negatively charged glutamic acid might restrict the self-assembly of collagen building blocks into a higher order structure. Meanwhile, the optimal fibrillogenesis condition is achieved when the concentration of lysine reaches to 1 mM. Both scanning electron microscopy (SEM) and atomic force microscope (AFM) analysis indicates that compared to pure collagen fibrils, the reconstructed collagen-lysine co-fibrils exhibit a higher degree of inter-fiber entanglements with more straight and longer fibrils. Noted that the specific D-period patterns of the reconstructed collagen fibrils could be clearly discernible and the width of D-banding increases steadily after introducing lysine. Besides, the kinetic and thermodynamic collagen self-assembly analysis confirms that the rate constants of both the first and second assembly phase decrease after introducing lysine, and lysine could promote the process of collagen fibrillogenesis obeying the laws of thermodynamics. - Highlights: • The effects of two different charged amino acids in collagen chains on the collagen fibrillogenesis were evaluated. • The positively charged lysine could improve the sizes or amounts of self-assembled collagen fibrils. • The width of D-banding of the collagen-lysine co-fibrils increased steadily after introducing lysine. • The optimal fibrillogenesis was achieved when the concentration of lysine reached to 1 mM. • The kinetic and thermodynamic collagen self-assembly were both analyzed.

  16. Critical lysine residues of Klf4 required for protein stabilization and degradation

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Key-Hwan; Kim, So-Ra; Ramakrishna, Suresh; Baek, Kwang-Hyun, E-mail: baek@cha.ac.kr

    2014-01-24

    Highlights: • Klf4 undergoes the 26S proteasomal degradation by ubiquitination on its multiple lysine residues. • Essential Klf4 ubiquitination sites are accumulated between 190–263 amino acids. • A mutation of lysine at 232 on Klf4 elongates protein turnover. • Klf4 mutants dramatically suppress p53 expression both under normal and UV irradiated conditions. - Abstract: The transcription factor, Krüppel-like factor 4 (Klf4) plays a crucial role in generating induced pluripotent stem cells (iPSCs). As the ubiquitination and degradation of the Klf4 protein have been suggested to play an important role in its function, the identification of specific lysine sites that are responsible for protein degradation is of prime interest to improve protein stability and function. However, the molecular mechanism regulating proteasomal degradation of the Klf4 is poorly understood. In this study, both the analysis of Klf4 ubiquitination sites using several Klf4 deletion fragments and bioinformatics predictions showed that the lysine sites which are signaling for Klf4 protein degradation lie in its N-terminal domain (aa 1–296). The results also showed that Lys32, 52, 232, and 252 of Klf4 are responsible for the proteolysis of the Klf4 protein. These results suggest that Klf4 undergoes proteasomal degradation and that these lysine residues are critical for Klf4 ubiquitination.

  17. PLMD: An updated data resource of protein lysine modifications.

    Science.gov (United States)

    Xu, Haodong; Zhou, Jiaqi; Lin, Shaofeng; Deng, Wankun; Zhang, Ying; Xue, Yu

    2017-05-20

    Post-translational modifications (PTMs) occurring at protein lysine residues, or protein lysine modifications (PLMs), play critical roles in regulating biological processes. Due to the explosive expansion of the amount of PLM substrates and the discovery of novel PLM types, here we greatly updated our previous studies, and presented a much more integrative resource of protein lysine modification database (PLMD). In PLMD, we totally collected and integrated 284,780 modification events in 53,501 proteins across 176 eukaryotes and prokaryotes for up to 20 types of PLMs, including ubiquitination, acetylation, sumoylation, methylation, succinylation, malonylation, glutarylation, glycation, formylation, hydroxylation, butyrylation, propionylation, crotonylation, pupylation, neddylation, 2-hydroxyisobutyrylation, phosphoglycerylation, carboxylation, lipoylation and biotinylation. Using the data set, a motif-based analysis was performed for each PLM type, and the results demonstrated that different PLM types preferentially recognize distinct sequence motifs for the modifications. Moreover, various PLMs synergistically orchestrate specific cellular biological processes by mutual crosstalks with each other, and we totally found 65,297 PLM events involved in 90 types of PLM co-occurrences on the same lysine residues. Finally, various options were provided for accessing the data, while original references and other annotations were also present for each PLM substrate. Taken together, we anticipated the PLMD database can serve as a useful resource for further researches of PLMs. PLMD 3.0 was implemented in PHP + MySQL and freely available at http://plmd.biocuckoo.org. Copyright © 2017 Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and Genetics Society of China. Published by Elsevier Ltd. All rights reserved.

  18. The Global Acetylome of the Human Pathogen Vibrio cholerae V52 Reveals Lysine Acetylation of Major Transcriptional Regulators

    DEFF Research Database (Denmark)

    Jers, Carsten; Ravikumar, Vaishnavi; Lezyk, Mateusz Jakub

    2018-01-01

    Protein lysine acetylation is recognized as an important reversible post translational modification in all domains of life. While its primary roles appear to reside in metabolic processes, lysine acetylation has also been implicated in regulating pathogenesis in bacteria. Several global lysine...... acetylome analyses have been carried out in various bacteria, but thus far there have been no reports of lysine acetylation taking place in the important human pathogen Vibrio cholerae. In this study, we analyzed the lysine acetylproteome of the human pathogen V. cholerae V52. By applying a combination...... in direct regulation of virulence in V. cholerae were acetylated. In conclusion, this is the first global protein lysine acetylome analysis of V. cholerae and should constitute a valuable resource for in-depth studies of the impact of lysine acetylation in pathogenesis and other cellular processes....

  19. Lysine Acetylation of CREBH Regulates Fasting-Induced Hepatic Lipid Metabolism

    Science.gov (United States)

    Kim, Hyunbae; Mendez, Roberto; Chen, Xuequn; Fang, Deyu

    2015-01-01

    Cyclic AMP-responsive element-binding protein 3-like 3, hepatocyte specific (CREBH), is a hepatic transcription factor that functions as a key regulator of energy homeostasis. Here, we defined a regulatory CREBH posttranslational modification process, namely, lysine-specific acetylation, and its functional involvement in fasting-induced hepatic lipid metabolism. Fasting induces CREBH acetylation in mouse livers in a time-dependent manner, and this event is critical for CREBH transcriptional activity in regulating hepatic lipid homeostasis. The histone acetyltransferase PCAF-mediated acetylation and the deacetylase sirtuin-1-mediated deacetylation coexist to maintain CREBH acetylation states under fasting conditions. Site-directed mutagenesis and functional analyses revealed that the lysine (K) residue at position 294 (K294) within the bZIP domain of the CREBH protein is the site where fasting-induced acetylation/deacetylation occurs. Introduction of the acetylation-deficient (K294R) or acetylation-mimicking (K294Q) mutation inhibited or enhanced CREBH transcriptional activity, respectively. Importantly, CREBH acetylation at lysine 294 was required for the interaction and synergy between CREBH and peroxisome proliferator-activated receptor α (PPARα) in activating their target genes upon fasting or glucagon stimulation. Introduction of the CREBH lysine 294 mutation in the liver leads to hepatic steatosis and hyperlipidemia in animals under prolonged fasting. In summary, our study reveals a molecular mechanism by which fasting or glucagon stimulation modulates lipid homeostasis through acetylation of CREBH. PMID:26438600

  20. Induction of monooxygenases and incorporation of radioactivity from 2-14C-lysine into hepatic microsomes of phenobarbital-treated rats fed a diet deficient in lysine, methionine, threonine and vitamines A, C, E

    International Nuclear Information System (INIS)

    Nurmagambetov, T.Zh.; Amirov, B.B.; Kuanysheva, T.G.; Sharmanov, T.Sh.

    1992-01-01

    The effect of diet on induction of monooxygenases and distribution of radioactivity from 2- 14 C-lysine in fractions of liver homogenate, muscle homogenate and blood of male rats treated with phenobarbital was studied. 2- 14 C-lysin was injected intraperitoneally 24 h before the first injection of phenobarbital. It was demonstrated that monooxygenase induction, increase of relative liver weight and incorporation of radioactivity from 2- 14 C-lysine into fractions of liver homogenate in phenobarbital-treated rats fed diet deficient in lysine, methionine, threonine and vitamins A, C, E were more pronounced as compared with the similarly treated rats which were fed a balanced diet. The possibility of mobilization of deficient essencial components to liver from other organs and tissues for maintenance of monooxygenase induction iis discussed

  1. Lysine supplementation in late gestation of gilts: effects on piglet birth weight, and gestational and lactational performance

    Directory of Open Access Journals (Sweden)

    Diogo Magnabosco

    2013-08-01

    Full Text Available Lysine requirements for gain in maternal body reserves and piglet birth weight, during pregnancy, in contemporary prolific genotypes, are not well established. This study aimed to evaluate the effect of dietary lysine in late pregnancy on piglet birth weight, and on the gestational and lactational performance of gilts. Pregnant gilts were uniformly distributed into two groups and received, from 85 to 110 days of gestation, either of two lysine levels in their diet: Control group - 28g lysine/day (n=136, and Lysine group - 35g lysine/day (n=141. There were no effects (P>0.10 of supplemental lysine on body weight and backfat (BF gain of females or on piglet birth weight. Gilts supplemented with lysine tended to have a lower percentage of stillbirths (P=0.077, reduced within-litter birth weight variation (P=0.094 and a lower percentage of piglets weighing less than 1100g (P=0.082 than in the Control group. During lactation, the performance of sows and litters was also evaluated in a subgroup of sows (n=26/group. There were no differences between the Control and Lysine groups (P>0.10 in voluntary feed intake, body reserve losses (weight and BF, weaning-to-estrus interval of the sows, and litter weaning weight. In conclusion, an increase in lysine (from 28 to 35g/day in late gestation of gilts (85 to 110 days tends to reduce the rate of stillbirths and to improve the uniformity of litter weight at birth, but does not affect the performance of females until farrowing or during subsequent lactation.

  2. Effect of exogenous CNT on kinetics of 3H-lysine in haerbin white rabbits

    International Nuclear Information System (INIS)

    Liu Dengke; Zan Linsen; Liu Yongfeng

    2007-01-01

    Haerbin White rabbits was used as testimonial and trace kinetics and radioimmunoassay and other techniques were used to study the distribution, transportation and metabolism of 3 H-Lysine in the animal. The metabolic kinetics of 3 H-Lysine could be described by the follows equation: (Y-circumflex) (t) =983.6281e -0.021935t + 1773.9999e -0.083932t - 983.6281e -0.432590t - 0773.9999e -0.050399t + 300.2820. Experimental results showed that 3 H-Lysine was accumulated mainly in kidney, heart, liver, spleen and muscle in check group; accumulated mainly in muscle, stomach, liver, heart and genitalia in cAMP treated group; accumulated in bladder, muscle, lung and intestine in cGMP treated group; and accumulated mainly in muscle, bladder, genitalia an fat in cAMP + cGMP treated group, respectively. The distribution of 3 H-Lysine was of evidently variations being treated with exogenous CNT. The results indicated that the distribution, transportation and metabolism of 3 H-Lysine were significantly affected by exogenous CNT in the Haerbin White rabbit. (authors)

  3. Effects of fortified lysine on the amino acid profile and sensory qualities of deep-fried and dried noodles.

    Science.gov (United States)

    Polpuech, C; Chavasit, V; Srichakwal, P; Paniangvait, P

    2011-08-01

    Lysine fortification of wheat flour has been used toward reducing protein energy malnutrition in developing countries. The feasibility of fortifying instant noodles with lysine was evaluated based on sensory qualities and the residual lysine content. Fifty grams of deep-fried and dried instant noodles were fortified with 0.23 and 0.21 g lysine, respectively. The production temperatures used for deep-frying were 165-175 degrees C and for drying, 80-105 degrees C; these are the temperatures used in the industrial production of both kinds of noodles. Lysine fortification was then performed at the local factories using the commercial production lines and packaging for both types of instant noodles. Both fortified and unfortified deep-fried and dried instant noodles were stored at 50 degrees C under fluorescent light for 2 and 4 months, respectively. The fortified products were tested for residual lysine content and sensory qualities as compared with unfortified noodles. The results show fortified products from the tested processing temperatures were all accepted. After storage, significant losses of lysine were not found in both types of noodles analysed. The lysine-fortified noodles had amino acid scores of 102% and 122%, respectively. After 2 months, the sensory quality of fortified deep-fried noodles was still acceptable; however, the dried noodles turned to an unacceptable dark colour. This study shows that it is feasible to fortify deep-fried instant noodles with lysine, though lysine fortification exhibited an undesirable colour in the dried instant noodles after storage.

  4. Lysine-functionalized nanodiamonds: synthesis, physiochemical characterization, and nucleic acid binding studies

    Science.gov (United States)

    Kaur, Randeep; Chitanda, Jackson M; Michel, Deborah; Maley, Jason; Borondics, Ferenc; Yang, Peng; Verrall, Ronald E; Badea, Ildiko

    2012-01-01

    Purpose: Detonation nanodiamonds (NDs) are carbon-based nanomaterials that, because of their size (4–5 nm), stable inert core, alterable surface chemistry, fluorescence, and biocompatibility, are emerging as bioimaging agents and promising tools for the delivery of biochemical molecules into cellular systems. However, diamond particles possess a strong propensity to aggregate in liquid formulation media, restricting their applicability in biomedical sciences. Here, the authors describe the covalent functionalization of NDs with lysine in an attempt to develop nanoparticles able to act as suitable nonviral vectors for transferring genetic materials across cellular membranes. Methods: NDs were oxidized and functionalized by binding lysine moieties attached to a three-carbon-length linker (1,3-diaminopropane) to their surfaces through amide bonds. Raman and Fourier transform infrared spectroscopy, zeta potential measurement, dynamic light scattering, atomic force microscopic imaging, and thermogravimetric analysis were used to characterize the lysine-functionalized NDs. Finally, the ability of the functionalized diamonds to bind plasmid DNA and small interfering RNA was investigated by gel electrophoresis assay and through size and zeta potential measurements. Results: NDs were successfully functionalized with the lysine linker, producing surface loading of 1.7 mmol g−1 of ND. These modified NDs formed highly stable aqueous dispersions with a zeta potential of 49 mV and particle size of approximately 20 nm. The functionalized NDs were found to be able to bind plasmid DNA and small interfering RNA by forming nanosized “diamoplexes”. Conclusion: The lysine-substituted ND particles generated in this study exhibit stable aqueous formulations and show potential for use as carriers for genetic materials. PMID:22904623

  5. Tracking the behavior of Maillard browning in lysine/arginine-sugar model systems under high hydrostatic pressure.

    Science.gov (United States)

    Ma, Xiao-Juan; Gao, Jin-Yan; Tong, Ping; Li, Xin; Chen, Hong-Bing

    2017-12-01

    High-pressure processing is gaining popularity in the food industry. However, its effect on the Maillard reaction during high-pressure-assisted pasteurization and sterilization is not well documented. This study aimed to investigate the effects of high hydrostatic pressure on the Maillard reaction during these processes using amino acid (lysine or arginine)-sugar (glucose or fructose) solution models. High pressure retarded the intermediate and final stages of the Maillard reaction in the lysine-sugar model. For the lysine-glucose model, the degradation rate of Amadori compounds was decelerated, while acceleration was observed in the arginine-sugar model. Increased temperature not only accelerated the Maillard reaction over time but also formed fluorescent compounds with different emission wavelengths. Lysine reacted with the sugars more readily than arginine under the same conditions. In addition, it was easier for lysine to react with glucose, whereas arginine reacted more readily with fructose under high pressure. High pressure exerts different effects on lysine-sugar and arginine-sugar models. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  6. High lysine and high yielding mutants in wheat (Triticum aestivum) L

    International Nuclear Information System (INIS)

    Mohammad, T.; Mahmood, F.; Ahmad, A.; Sattar, A.; Khan, I.

    1988-01-01

    The dry seeds of the variety Lu-26 were irradiated with 20 krad of gamma rays. In M 2 about 300 mutant plants were selected for short stature, rust resistance and other desirable traits. As a result of further selection, in M 6 , eight superior lines were finally identified. The agronomic characteristics of these mutants, the parent variety (Lu-26) and a standard check variety (Pak-81) are shown. The selected mutants and commercially grown cultivars (Lu-26 and Pak-81) were studied for total protein content and amino acid pattern. The mutants WM-89-1, WM-6-17 and WM-81-2 showing high yield also contained comparatively high amounts of methionine and lysine. The lysine contents were 565, 410, and 370 mg/100g in the mutants WM-89-1, WM-6-17 and WM-81-2, respectively against a range value of 210-370 mg/100g in other mutants and 250-320 in the commercial cultivars. The mutant WM-81-2 was comparable to WM-56-1-5 in lysine content. The results of these experiments show a possibility of developing varieties having high yield and high amounts of essential amino acids such as lysine and methionine

  7. Machine Learning of Human Pluripotent Stem Cell-Derived Engineered Cardiac Tissue Contractility for Automated Drug Classification

    Directory of Open Access Journals (Sweden)

    Eugene K. Lee

    2017-11-01

    Full Text Available Accurately predicting cardioactive effects of new molecular entities for therapeutics remains a daunting challenge. Immense research effort has been focused toward creating new screening platforms that utilize human pluripotent stem cell (hPSC-derived cardiomyocytes and three-dimensional engineered cardiac tissue constructs to better recapitulate human heart function and drug responses. As these new platforms become increasingly sophisticated and high throughput, the drug screens result in larger multidimensional datasets. Improved automated analysis methods must therefore be developed in parallel to fully comprehend the cellular response across a multidimensional parameter space. Here, we describe the use of machine learning to comprehensively analyze 17 functional parameters derived from force readouts of hPSC-derived ventricular cardiac tissue strips (hvCTS electrically paced at a range of frequencies and exposed to a library of compounds. A generated metric is effective for then determining the cardioactivity of a given drug. Furthermore, we demonstrate a classification model that can automatically predict the mechanistic action of an unknown cardioactive drug.

  8. Molecular evolution of the lysine biosynthetic pathways.

    Science.gov (United States)

    Velasco, A M; Leguina, J I; Lazcano, A

    2002-10-01

    Among the different biosynthetic pathways found in extant organisms, lysine biosynthesis is peculiar because it has two different anabolic routes. One is the diaminopimelic acid pathway (DAP), and the other over the a-aminoadipic acid route (AAA). A variant of the AAA route that includes some enzymes involved in arginine and leucine biosyntheses has been recently reported in Thermus thermophilus (Nishida et al. 1999). Here we describe the results of a detailed genomic analysis of each of the sequences involved in the two lysine anabolic routes, as well as of genes from other routes related to them. No evidence was found of an evolutionary relationship between the DAP and AAA enzymes. Our results suggest that the DAP pathway is related to arginine metabolism, since the lysC, asd, dapC, dapE, and lysA genes from lysine biosynthesis are related to the argB, argC, argD, argE, and speAC genes, respectively, whose products catalyze different steps in arginine metabolism. This work supports previous reports on the relationship between AAA gene products and some enzymes involved in leucine biosynthesis and the tricarboxylic acid cycle (Irvin and Bhattacharjee 1998; Miyazaki et al. 2001). Here we discuss the significance of the recent finding that several genes involved in the arginine (Arg) and leucine (Leu) biosynthesis participate in a new alternative route of the AAA pathway (Miyazaki et al. 2001). Our results demonstrate a clear relationship between the DAP and Arg routes, and between the AAA and Leu pathways.

  9. Comprehensive assessment of the L-lysine production process from fermentation of sugarcane molasses.

    Science.gov (United States)

    Anaya-Reza, Omar; Lopez-Arenas, Teresa

    2017-07-01

    L-Lysine is an essential amino acid that can be produced by chemical processes from fossil raw materials, as well as by microbial fermentation, the latter being a more efficient and environmentally friendly procedure. In this work, the production process of L-lysine-HCl is studied using a systematic approach based on modeling and simulation, which supports decision making in the early stage of process design. The study considers two analysis stages: first, the dynamic analysis of the fermentation reactor, where the conversion of sugars from sugarcane molasses to L-lysine with a strain of Corynebacterium glutamicum is carried out. In this stage, the operation mode (either batch or fed batch) and operating conditions of the fermentation reactor are defined to reach the maximum technical criteria. Afterwards, the second analysis stage relates to the industrial production process of L-lysine-HCl, where the fermentation reactor, upstream processing, and downstream processing are included. In this stage, the influence of key parameters on the overall process performance is scrutinized through the evaluation of several technical, economic, and environmental criteria, to determine a profitable and sustainable design of the L-lysine production process. The main results show how the operating conditions, process design, and selection of evaluation criteria can influence in the conceptual design. The best plant design shows maximum product yield (0.31 g L-lysine/g glucose) and productivity (1.99 g/L/h), achieving 26.5% return on investment (ROI) with a payback period (PBP) of 3.8 years, decreasing water and energy consumption, and with a low potential environmental impact (PEI) index.

  10. Proteomic investigations of lysine acetylation identify diverse substrates of mitochondrial deacetylase sirt3

    DEFF Research Database (Denmark)

    Sol, E-ri Maria; Wagner, Sebastian A; Weinert, Brian T

    2012-01-01

    Lysine acetylation is a posttranslational modification that is dynamically regulated by the activity of acetyltransferases and deacetylases. The human and mouse genomes encode 18 different lysine deacetylases (KDACs) which are key regulators of many cellular processes. Identifying substrates...... of KDACs and pinpointing the regulated acetylation sites on target proteins may provide important information about the molecular basis of their functions. Here we apply quantitative proteomics to identify endogenous substrates of the mitochondrial deacetylase Sirtuin 3 (Sirt3) by comparing site...... by modulating acetylation on diverse substrates. The experimental strategy described here is generic and can be applied to identify endogenous substrates of other lysine deacetylases....

  11. [Benzimidazole and its derivatives--from fungicides to designer drugs. A new occupational and environmental hazards].

    Science.gov (United States)

    Lutz, Piotr

    2012-01-01

    Benzimidazole and benzimidazole derivatives play an important role in controlling various fungal pathogens. The benzimidazoles are also used to treat nematode and trematode infections in humans and animals. It acts by binding to the microtubules and stopping hyphal growth. It also binds to the spindle microtubules and blocks nuclear division. The most popular fungicide is carbendazim. The fungicide is used to control plant diseases in cereals and fruits. Laboratory studies have shown that carbendazim cause infertility and destroy the testicles of laboratory animals. Other benzimidazole derivatives are used as a preservative in paint, textile, papermaking, leather industry, and warehousing practices, as well as a preservative of fruits. Occupational exposure to benzimidazole may occur through inhalation and dermal contact with those compounds at workplaces where benzimidazole is used or produced. Some of the benzimidazoles are common environmental pollutants. They are often found in food and fruit products. Some of the benzimidazoles, like a astemizole or esomeprazole have found applications in diverse therapeutical areas. Despite of the clear advantages afforded by the use of benzimidazole derivatives, they share a danger potential. The most hazardous, however, are new illegally synthesed psychoactive drugs known as designer drugs. Some of them, like nitazene, etonitazene or clonitazene belong to benzimidazole derivatives. Laboratory animal studies revealed that etonitazene produced very similar effects in central nervous system as those observed after morphine administration. Considering etonitazene's properties, it seems reasonable to expected that long-term exposure to other benzimidazole derivatives may result in drug abuse and development of drug dependence.

  12. Simple, rapid, and sensitive liquid chromatography-fluorescence method for the quantification of tranexamic acid in blood

    NARCIS (Netherlands)

    Huertas-Pérez, José Fernando; Heger, Michal; Dekker, Henk; Krabbe, Hans; Lankelma, Jan; Ariese, Freek

    2007-01-01

    Tranexamic acid (TA) is a synthetic antifibrinolytic agent that is being considered as a candidate adjuvant drug for site-specific pharmaco-laser therapy of port wine stains. For drug utility studies, a high-performance liquid chromatography (HPLC)-fluorescence method was developed for the

  13. Lysine supplementation is not effective for the prevention or treatment of feline herpesvirus 1 infection in cats: a systematic review.

    Science.gov (United States)

    Bol, Sebastiaan; Bunnik, Evelien M

    2015-11-16

    Feline herpesvirus 1 is a highly contagious virus that affects many cats. Virus infection presents with flu-like signs and irritation of ocular and nasal regions. While cats can recover from active infections without medical treatment, examination by a veterinarian is recommended. Lysine supplementation appears to be a popular intervention (recommended by > 90 % of veterinarians in cat hospitals). We investigated the scientific merit of lysine supplementation by systematically reviewing all relevant literature. NCBI's PubMed database was used to search for published work on lysine and feline herpesvirus 1, as well as lysine and human herpesvirus 1. Seven studies on lysine and feline herpesvirus 1 (two in vitro studies and 5 studies with cats), and 10 publications on lysine and human herpesvirus 1 (three in vitro studies and 7 clinical trials) were included for qualitative analysis. There is evidence at multiple levels that lysine supplementation is not effective for the prevention or treatment of feline herpesvirus 1 infection in cats. Lysine does not have any antiviral properties, but is believed to act by lowering arginine levels. However, lysine does not antagonize arginine in cats, and evidence that low intracellular arginine concentrations would inhibit viral replication is lacking. Furthermore, lowering arginine levels is highly undesirable since cats cannot synthesize this amino acid themselves. Arginine deficiency will result in hyperammonemia, which may be fatal. In vitro studies with feline herpesvirus 1 showed that lysine has no effect on the replication kinetics of the virus. Finally, and most importantly, several clinical studies with cats have shown that lysine is not effective for the prevention or the treatment of feline herpesvirus 1 infection, and some even reported increased infection frequency and disease severity in cats receiving lysine supplementation. We recommend an immediate stop of lysine supplementation because of the complete lack of

  14. Insight into the collagen assembly in the presence of lysine and glutamic acid: An in vitro study.

    Science.gov (United States)

    Liu, Xinhua; Dan, Nianhua; Dan, Weihua

    2017-01-01

    The aim of this study is to evaluate the effects of two different charged amino acids in collagen chains, lysine and glutamic acid, on the fibrillogenesis process of collagen molecules. The turbidity, zeta potential, and fiber diameter analysis suggest that introducing the positively charged lysine into collagen might improve the sizes or amounts of the self-assembled collagen fibrils significantly. Conversely, the negatively charged glutamic acid might restrict the self-assembly of collagen building blocks into a higher order structure. Meanwhile, the optimal fibrillogenesis condition is achieved when the concentration of lysine reaches to 1mM. Both scanning electron microscopy (SEM) and atomic force microscope (AFM) analysis indicates that compared to pure collagen fibrils, the reconstructed collagen-lysine co-fibrils exhibit a higher degree of inter-fiber entanglements with more straight and longer fibrils. Noted that the specific D-period patterns of the reconstructed collagen fibrils could be clearly discernible and the width of D-banding increases steadily after introducing lysine. Besides, the kinetic and thermodynamic collagen self-assembly analysis confirms that the rate constants of both the first and second assembly phase decrease after introducing lysine, and lysine could promote the process of collagen fibrillogenesis obeying the laws of thermodynamics. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Performance comparison between crystalline and co-amorphous salts of indomethacin-lysine

    DEFF Research Database (Denmark)

    Kasten, Georgia; Nouri, Khatera; Grohganz, Holger

    2017-01-01

    The introduction of a highly water soluble amino acid as co-amorphous co-former has previously been shown to significantly improve the dissolution rate of poorly water soluble drugs. In this work, dry ball milling (DBM) and liquid assisted grinding (LAG) were used to prepare different physical...... forms of salts of indomethacin (IND) with the amino acid lysine (LYS), allowing the direct comparison of their solid-state properties to their in vitro performance. X-ray powder diffraction and Fourier-transformed infrared spectroscopy showed that DBM experiments led to the formation of a fully co......-amorphous salt, while LAG resulted in a crystalline salt. Differential scanning calorimetry showed that the samples prepared by DBM had a single glass transition temperature (Tg) of approx. 100°C for the co-amorphous salt, while a new melting point (223°C) was obtained for the crystalline salt prepared by LAG...

  16. Fortification of lysine for improving protein quality in multiple-fortified quick cooking rice : Review

    NARCIS (Netherlands)

    Wongmetinee, T.; Boonstra, A.; Zimmermann, M.B.; Chavasit, V.

    2009-01-01

    Previous studies in Thailand indicated that rice-based complementary foods of breast-fed infants normally provided inadequate iron and calcium. Quick-cooking rice fortified with different nutrients was therefore developed. The idea of lysine fortification was based on the fact that lysine is a

  17. Lysine-vasopressin analogues with glycoconjugates in position 8

    Czech Academy of Sciences Publication Activity Database

    Marcinkowska, A.; Borovičková, Lenka; Slaninová, Jiřina; Grzonka, Z.

    2006-01-01

    Roč. 80, č. 5 (2006), s. 759-766 ISSN 0137- 5083 Institutional research plan: CEZ:AV0Z40550506 Keywords : glycoconjugates * glycopeptides * lysine-vasopressin analogues Subject RIV: CC - Organic Chemistry Impact factor: 0.491, year: 2006

  18. [Expression of the genes for lysine biosynthesis of Bacillus subtilis in Escherichia coli cells].

    Science.gov (United States)

    Shevchenko, T N; Okunev, O V; Aleksieva, Z M; Maliuta, S S

    1984-01-01

    Hybrid plasmids pLRS33 and pLRB4 containing Bac. subtilis genes coding lysin biosynthesis were subjected to genetical analysis. It is shown that after pLRS33- and pLRB4- transformation of E. coli strains, auxotrophic relative to lysin and diaminopimelic acid, there occurs complementation of dapA, dapB, dapC, dapD, dapE, lysA mutations by plasmid pLRS33 and of dapC, dapB, lysA mutations by plasmid pLRB4. The plasmids are studied for their influence on the level of lysin and its precurror synthesis in E. coli strains.

  19. Dgroup: DG01908 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available DG01908 DGroup Antiinflammatory drug, propionic acid derivatives ... DG00245 ... Ibuprofen ... D00126 ... Ibuprofen... (JP17/USP/INN) ... D01122 ... Ibuprofen piconol (JP17/USAN) ... D04490 ... Ibuprofen aluminum (USAN) ... D06606 ... Ibupro...fen lysine (USAN); Ibuprofen L-lysine (JAN) ... D08058 ... Ibuprofen arginine salt ... D08059 ... Ibuprofen... sodium ... D09760 ... Ibuprofen sodium (USAN) DG00455 ... Naproxen ... D00118

  20. Studies of lysine cyclodeaminase from Streptomyces pristinaespiralis: Insights into the complex transition NAD+ state.

    Science.gov (United States)

    Ying, Hanxiao; Wang, Jing; Shi, Ting; Zhao, Yilei; Wang, Xin; Ouyang, Pingkai; Chen, Kequan

    2018-01-01

    Lysine cyclodeaminase (LCD) catalyzes the piperidine ring formation in macrolide-pipecolate natural products metabolic pathways from a lysine substrate through a combination of cyclization and deamination. This enzyme belongs to a unique enzyme class, which uses NAD + as the catalytic prosthetic group instead of as the co-substrate. To understand the molecular details of NAD + functions in lysine cyclodeaminase, we have determined four ternary crystal structure complexes of LCD-NAD + with pipecolic acid (LCD-PA), lysine (LCD-LYS), and an intermediate (LCD-INT) as ligands at 2.26-, 2.00-, 2.17- and 1.80 Å resolutions, respectively. By combining computational studies, a NAD + -mediated "gate keeper" function involving NAD + /NADH and Arg49 that control the binding and entry of the ligand lysine was revealed, confirming the critical roles of NAD + in the substrate access process. Further, in the gate opening form, a substrate delivery tunnel between ε-carboxyl moiety of Glu264 and the α-carboxyl moiety of Asp236 was observed through a comparison of four structure complexes. The LCD structure details including NAD + -mediated "gate keeper" and substrate tunnel may assist in the exploration the NAD + function in this unique enzyme class, and in regulation of macrolide-pipecolate natural product synthesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Structural Basis of Histone Demethylase KDM6B Histone 3 Lysine 27 Specificity

    DEFF Research Database (Denmark)

    Jones, Sarah E; Olsen, Lars; Gajhede, Michael

    2018-01-01

    KDM subfamily 6 enzymes KDM6A and KDM6B specifically catalyze demethylation of di- and trimethylated lysine on histone 3 lysine 27 (H3K27me3/2) and play an important role in repression of developmental genes. Despite identical amino acid sequence in the immediate surroundings of H3K9me3/2 (ARKS...

  2. Derivative Spectrophotometric Method for Estimation of Antiretroviral Drugs in Fixed Dose Combinations

    Science.gov (United States)

    P.B., Mohite; R.B., Pandhare; S.G., Khanage

    2012-01-01

    Purpose: Lamivudine is cytosine and zidovudine is cytidine and is used as an antiretroviral agents. Both drugs are available in tablet dosage forms with a dose of 150 mg for LAM and 300 mg ZID respectively. Method: The method employed is based on first order derivative spectroscopy. Wavelengths 279 nm and 300 nm were selected for the estimation of the Lamovudine and Zidovudine respectively by taking the first order derivative spectra. The conc. of both drugs was determined by proposed method. The results of analysis have been validated statistically and by recovery studies as per ICH guidelines. Result: Both the drugs obey Beer’s law in the concentration range 10-50 μg mL-1,for LAM and ZID; with regression 0.9998 and 0.9999, intercept – 0.0677 and – 0.0043 and slope 0.0457 and 0.0391 for LAM and ZID, respectively.The accuracy and reproducibility results are close to 100% with 2% RSD. Conclusion: A simple, accurate, precise, sensitive and economical procedures for simultaneous estimation of Lamovudine and Zidovudine in tablet dosage form have been developed. PMID:24312779

  3. Application of the fragment molecular orbital method analysis to fragment-based drug discovery of BET (bromodomain and extra-terminal proteins) inhibitors.

    Science.gov (United States)

    Ozawa, Motoyasu; Ozawa, Tomonaga; Ueda, Kazuyoshi

    2017-06-01

    The molecular interactions of inhibitors of bromodomains (BRDs) were investigated. BRDs are protein interaction modules that recognizing ε-N-acetyl-lysine (εAc-Lys) motifs found in histone tails and are promising protein-protein interaction (PPI) targets. First, we analyzed a peptide ligand containing εAc-Lys to evaluate native PPIs. We then analyzed tetrahydroquinazoline-6-yl-benzensulfonamide derivatives found by fragment-based drug design (FBDD) and examined their interactions with the protein compared with the peptide ligand in terms of the inter-fragment interaction energy. In addition, we analyzed benzodiazepine derivatives that are high-affinity ligands for BRDs and examined differences in the CH/π interactions of the amino acid residues. We further surveyed changes in the charges of the amino acid residues among individual ligands, performed pair interaction energy decomposition analysis and estimated the water profile within the ligand binding site. Thus, useful insights for drug design were provided. Through these analyses and considerations, we show that the FMO method is a useful drug design tool to evaluate the process of FBDD and to explore PPI inhibitors. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Thrombin-activatable fibrinolysis inhibitor is degraded by Salmonella enterica and Yersinia pestis.

    Science.gov (United States)

    Valls Serón, M; Haiko, J; DE Groot, P G; Korhonen, T K; Meijers, J C M

    2010-10-01

     Pathogenic bacteria modulate the host coagulation system to evade immune responses or to facilitate dissemination through extravascular tissues. In particular, the important bacterial pathogens Salmonella enterica and Yersinia pestis intervene with the plasminogen/fibrinolytic system. Thrombin-activatable fibrinolysis inhibitor (TAFI) has anti-fibrinolytic properties as the active enzyme (TAFIa) removes C-terminal lysine residues from fibrin, thereby attenuating accelerated plasmin formation.  Here, we demonstrate inactivation and cleavage of TAFI by homologous surface proteases, the omptins Pla of Y. pestis and PgtE of S. enterica. We show that omptin-expressing bacteria decrease TAFI activatability by thrombin-thrombomodulin and that the anti-fibrinolytic potential of TAFIa was reduced by recombinant Escherichia coli expressing Pla or PgtE. The functional impairment resulted from C-terminal cleavage of TAFI by the omptins.  Our results indicate that TAFI is degraded directly by the omptins PgtE of S. enterica and Pla of Y. pestis. This may contribute to the ability of PgtE and Pla to damage tissue barriers, such as fibrin, and thereby to enhance spread of S. enterica and Y. pestis during infection. © 2010 International Society on Thrombosis and Haemostasis.

  5. Intravenous lysine clonixinate for the acute treatment of severe migraine attacks: a double-blind, randomized, placebo-controlled study

    Directory of Open Access Journals (Sweden)

    Abouch Valenty Krymchantowski, MD, PhD

    2003-09-01

    Full Text Available Background: Several nonsteroidal anti-inflammatory drugs (NSAIDs have been shown to be effective in the treatment of migraine. However, few commercially available NSAIDs can be administered IV. Lysine clonixinate (LC, an NSAID derived from nicotinic acid, has been proved effective in various algesic syndromes (eg, renal colic, muscular pain, nerve compression, odontalgia. The oral formulation of LC has been shown to be effective in the treatment of migraine of moderate severity. Objective: The aim of this study was to assess the efficacy and tolerability of the IV formulation of LC in the treatment of severe migraine. Methods: This double-blind, randomized, placebo-controlled, prospective study enrolled patients with severe migraine (without aura as defined by the criteria of the International Headache Society. When patients presented to a neurology hospital with an outpatient headache unit (Instituto de Neurologia Deolindo Couto, Rio de Janeiro, Brazil with a severe migraine attack that had lasted <4 hours, they were randomized to 1 of 2 groups (IV placebo [25 mL of 0.9% saline] or IV LC [21 mL of 0.9% saline plus 4 mL of LC 200 mg]. Headache intensity and adverse effects (AEs were assessed before (0 minute and 30, 60, and 90 minutes after study drug administration. Rescue medication was available 2 hours after study drug administration, and its use was compared between groups. Results: Thirty-two patients (23 women, 9 men; mean [SD] age, 32 [2] years; range, 18–58 years entered the study. Twenty-nine patients (21 women, 8 men; mean [SD] age, 32 [2] years; range, 18–56 years completed the study. Three patients (all in the placebo group did not complete the study (1 patient was unable to rate the pain severity after drug administration and 2 patients refused IV drug administration. Among study completers, 17 patients received LC and 12 placebo. At 30 minutes, 1 patient (8.3% in the placebo group and 5 patients (29.4% in the LC group were

  6. Utilization in rats of 14C-L-lysine-labeled casein browned by amino-carbonyl reaction

    International Nuclear Information System (INIS)

    Mori, Bunpei; Nakatsuji, Hirotaka.

    1977-01-01

    The investigation was carried out in order to elucidate the reason for the reduction in nutritive value of browned protein, by using labeled casein as a model protein. Goat casein preparation in which lysine residues had been labeled with 14 C was browned by amino-carbonyl reaction with glucose at 37 0 C. Browned or non-browned casein was ingested by growing rats by spaced feeding. When the rats ingested the browned casein the experimental group, higher radioactivity was found in TCA-soluble fraction in the small intestine as compared with that in the control group, while radioactivity was scarecely found in feces for 22 hr. Along with absorption delay, considerably high radioactivity was found in urine. The recovery of radioactivity in expired air of rats fed the labeled casein (browned and non-browned) was measured. In the experimental group, expired 14 CO 2 came out slower than the control group. From these results, it is suggested that the main reason for the reduction in nutritive value by browning reaction may be the formation of a lysine derivative in a protein, which remains in the small intestinal lumen as an absorption-delayed material and is finally excreted in urine. (auth.)

  7. Differential lysine acetylation profiles of Erwinia amylovora strains revealed by proteomics

    Science.gov (United States)

    Wu, Xia; Vellaichamy, Adaikkalam; Wang, Dongping; Zamdborg, Leonid; Kelleher, Neil L.; Huber, Steven C.; Zhao, Youfu

    2015-01-01

    Protein lysine acetylation (LysAc) has recently been demonstrated to be widespread in E. coli and Salmonella, and to broadly regulate bacterial physiology and metabolism. However, LysAc in plant pathogenic bacteria is largely unknown. Here we first report the lysine acetylome of Erwinia amylovora, an enterobacterium causing serious fire blight disease of apples and pears. Immunoblots using generic anti-lysine acetylation antibodies demonstrated that growth conditions strongly affected the LysAc profiles in E. amylovora. Differential LysAc profiles were also observed for two E. amylovora strains, known to have differential virulence in plants, indicating translational modification of proteins may be important in determining virulence of bacterial strains. Proteomic analysis of LysAc in two E. amylovora strains identified 141 LysAc sites in 96 proteins that function in a wide range of biological pathways. Consistent with previous reports, 44% of the proteins are involved in metabolic processes, including central metabolism, lipopolysaccharide, nucleotide and amino acid metabolism. Interestingly, for the first time, several proteins involved in E. amylovora virulence, including exopolysaccharide amylovoran biosynthesis- and type III secretion-associated proteins, were found to be lysine acetylated, suggesting that LysAc may play a major role in bacterial virulence. Comparative analysis of LysAc sites in E. amylovora and E. coli further revealed the sequence and structural commonality for LysAc in the two organisms. Collectively, these results reinforce the notion that LysAc of proteins is widespread in bacterial metabolism and virulence. PMID:23234799

  8. Adsorption of Lysine on Na-Montmorillonite and Competition with Ca(2+): A Combined XRD and ATR-FTIR Study.

    Science.gov (United States)

    Yang, Yanli; Wang, Shengrui; Liu, Jingyang; Xu, Yisheng; Zhou, Xiaoyun

    2016-05-17

    Lysine adsorption at clay/aqueous interfaces plays an important role in the mobility, bioavailability, and degradation of amino acids in the environment. Knowledge of these interfacial interactions facilitates our full understanding of the fate and transport of amino acids. Here, X-ray diffraction (XRD) and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) measurements were used to explore the dynamic process of lysine adsorption on montmorillonite and the competition with Ca(2+) at the molecular level. Density functional theory (DFT) calculations were employed to determine the peak assignments of dissolved lysine in the solution phase. Three surface complexes, including dicationic, cationic, and zwitterionic structures, were observed to attach to the clay edge sites and penetrate the interlayer space. The increased surface coverage and Ca(2+) competition did not affect the interfacial lysine structures at a certain pH, whereas an elevated lysine concentration contributed to zwitterionic-type coordination at pH 10. Moreover, clay dissolution at pH 4 could be inhibited at a higher surface coverage with 5 and 10 mM lysine, whereas the inhibition effect was inconspicuous or undetected at pH 7 and 10. The presence of Ca(2+) not only could remove a part of the adsorbed lysine but also could facilitate the readsorption of dissolved Si(4+) and Al(3+) and surface protonation. Our results provide new insights into the process of lysine adsorption and its effects on montmorillonite surface sites.

  9. Internalization and Subcellular Trafficking of Poly-l-lysine Dendrimers Are Impacted by the Site of Fluorophore Conjugation.

    Science.gov (United States)

    Avaritt, Brittany R; Swaan, Peter W

    2015-06-01

    Internalization and intracellular trafficking of dendrimer-drug conjugates play an important role in achieving successful drug delivery. In this study, we aimed to elucidate the endocytosis mechanisms and subcellular localization of poly-l-lysine (PLL) dendrimers in Caco-2 cells. We also investigated the impact of fluorophore conjugation on cytotoxicity, uptake, and transepithelial transport. Oregon green 514 (OG) was conjugated to PLL G3 at either the dendrimer periphery or the core. Chemical inhibitors of clathrin-, caveolin-, cholesterol-, and dynamin-mediated endocytosis pathways and macropinocytosis were employed to establish internalization mechanisms, while colocalization with subcellular markers was used to determine dendrimer trafficking. Cell viability, internalization, and uptake were all influenced by the site of fluorophore conjugation. Uptake was found to be highly dependent on cholesterol- and dynamin-mediated endocytosis as well as macropinocytosis. Dendrimers were trafficked to endosomes and lysosomes, and subcellular localization was impacted by the fluorophore conjugation site. The results of this study indicate that PLL dendrimers exploit multiple pathways for cellular entry, and internalization and trafficking can be impacted by conjugation. Therefore, design of dendrimer-drug conjugates requires careful consideration to achieve successful drug delivery.

  10. Bioconversion of Agricultural By-Products to Lysin by brevibacterium flavum and physico-chemical optimization for hyper-production

    International Nuclear Information System (INIS)

    Irshad, S.; Hashmi, A. S.; Babar, M. E.; Awan, A. R.; Anjum, A. A.; Javed, M. M.

    2015-01-01

    Poultry and agriculture industry has a great role in the development of food sector in Pakistan. Whole of the Lysine required for poultry feed is imported to fulfil the desired dietary needs. Present study was designed to utilize different agricultural by-products like molasses, wheat bran, rice polishing and corn steep liquor. Different Physico-Chemical parameters were optimized to have hyper-production of Lysine through fermentation by using Brevibacterium flavum as a fermentative agent. From wheat bran, rice polishing and molasses (as best carbon source), significantly high concentrations of lysine (10.4 g/L) after 72h of incubation was observed with molasses (4 percentage) with 3 percentage (v/v) inoculum size at 30 degree C and pH 7. Among different nitrogen sources, 0.25 percentage (NH/sub 4/)2SO/sub 4/ showed significantly (P< 0.05) high yield of Lysine (16.89 g/L). Addition of different optimum levels of ionic salts; 4 percentage CaCO/sub 3/, 0.4 percentage MgSO/sub 4/.7H/sub 2/O, 0.1 percentage NaCl and 0.2 percentage KH/sub 2/PO/sub 4/ gave significantly (P< 0.05) higher quantity of Lysine 19.01 g/L. Inclusion of 0.6 percentage corn steep liquor and 0.4 mg/100mL biotin significantly (P< 0.05) raised the Lysine from 19.4 g/L - 19.45 g/L. The presence of Lysine in fermented broth was detected by TLC. Thus a cheap and practical bioprocess of Lysine production was concluded, that can be exploited commercially to save foreign exchange. (author)

  11. Biological significance of lysine mono-, di- and trimethylation on histone and non-histone proteins

    International Nuclear Information System (INIS)

    Perez-Burgos, L.

    2006-01-01

    Histones are the proteins that compact DNA into the repeating unit of chromatin known as the nucleosome. The N-termini of histones are subject to a series of post-translational modifications, one of which is methylation. This modification is termed 'epigenetic' because it extends the information encoded in the genome. Lysines can be mono-, di- or tri-methylated at different positions on histones H1, H3 and H4. In order to study the biological role of histone lysine methylation, antibodies were generated against mono-, di- and trimethylated H3-K9 and H3-27. Indeed, different chromatin domains in the mouse nucleus are enriched in distinct forms of histone lysine methylation, such as pericentric heterochromatin and the inactive X chromosome. Interestingly, heterochromatin in Arabidopsis thaliana is enriched in the mono- and di-, but not the trimethylated form of H3-K9. Furthermore, there exists a hierarchy of epigenetic modifications in which H3-K9 trimethylation is found to be upstream of DNA methylation on mouse major satellites. Histone lysine methylation is also involved in gene regulation upon development. One example is the chicken 61538;-globin locus, a region of facultative chromatin that undergoes a loss of di- and trimethylated H3-K27 in mature red blood cells, concomitant with expression of the 61538;-globin genes. SET-domain proteins are enzymes that methylate histones, but some of them are also able to methylate non-histone substrates. In particular, p53 is methylated by Set9 on lysine 372, G9a and Glp-1 on lysine 373 and by Smyd2 on lysine 370. Smyd2 transcript levels are greatly increased upon irradiation and dimethylated p53-370 specifically binds to 53BP1, a protein involved in recognizing DNA double-stranded breaks upon ionizing radiation. These results argue for a novel role of p53-K370 methylation in the biology of DNA damage. In summary, lysine methylation is a post-translational modification that can occur both on histone and non-histone proteins

  12. Tranexamsyre reducerer blodtabet efter større elektive ortopædkirurgiske operationer

    DEFF Research Database (Denmark)

    Eschen, Camilla Tofte; Tengberg, Peter Toft; Husted, Henrik

    2012-01-01

    surgery as an antifibrinolytic agent. Several studies within the orthopaedic fields have underlined the effect of the drug in reducing blood loss and need for transfusions. However, more studies are needed to examine the optimal dosage and administration along with the risks associated with the drug....

  13. Proteome-wide analysis of lysine acetylation suggests its broad regulatory scope in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Henriksen, Peter; Wagner, Sebastian Alexander; Weinert, Brian Tate

    2012-01-01

    Post-translational modification of proteins by lysine acetylation plays important regulatory roles in living cells. The budding yeast Saccharomyces cerevisiae is a widely used unicellular eukaryotic model organism in biomedical research. S. cerevisiae contains several evolutionary conserved lysine...... acetyltransferases and deacetylases. However, only a few dozen acetylation sites in S. cerevisiae are known, presenting a major obstacle for further understanding the regulatory roles of acetylation in this organism. Here we use high resolution mass spectrometry to identify about 4000 lysine acetylation sites in S....... cerevisiae. Acetylated proteins are implicated in the regulation of diverse cytoplasmic and nuclear processes including chromatin organization, mitochondrial metabolism, and protein synthesis. Bioinformatic analysis of yeast acetylation sites shows that acetylated lysines are significantly more conserved...

  14. Effect of varying dietary concentrations of lysine on growth performance of the Pearl Grey guinea fowl.

    Science.gov (United States)

    Bhogoju, S; Nahashon, S N; Donkor, J; Kimathi, B; Johnson, D; Khwatenge, C; Bowden-Taylor, T

    2017-05-01

    Lysine is the second limiting essential amino acid in poultry nutrition after methionine. Understanding the lysine requirement of poultry is necessary in guiding formulation of least cost diets that effectively meet the nutritional needs of individual birds. The lysine requirement of the Pearl Grey guinea fowl (PGGF) is not known. Therefore, the objective of this study was to assess the appropriate lysine levels required for optimal growth attributes of the PGGF. In a 12-week study, 512 one-day-old Pearl Grey guinea keets were weighed individually and randomly assigned to electrically heated battery brooders. Each battery contained 12 compartments housing 15 birds each. Eight diets fed to the experimental birds consisted of corn-soybean meal and contained 0.80 to 1.22 digestible lysine in 0.06% increments. Feed and water were provided at free choice and the diets were replicated twice. Experimental diets contained 3,100 Kcal metabolizable energy (ME)/kg diet and 23% crude protein (CP), 3,150 ME Kcal ME/kg diet and 21% CP, and 3,100 ME/kg and 17% CP, at zero to 4, 5 to 10, and 11 to 12 weeks of age (WOA), respectively. Birds were provided water ad libitum and a 23:1 and 8:16-hr (light:dark) regimen at zero to 8 and 9 to 12 WOA, respectively. Birds were weighed weekly, and body weight gain, feed consumption, and feed conversions were determined. Data were analyzed using the General Linear Model (GLM) procedures of SAS (2002) with dietary lysine as treatment effect. Females responded better to diets containing 1.04 and 0.8% lysine from hatch to 4 and 5 to 12 WOA, respectively. Males responded better to diets containing 1.10 and 0.8% lysine at hatch to 4 WOA and 5 to 12 WOA, respectively. Therefore, we recommend that PGGF females and males be fed diets containing 1.04 and 1.10%, respectively, at hatch to 4 WOA and 0.80% lysine at 5 to 12 WOA. The diets should be supplied in phases. © 2016 Poultry Science Association Inc.

  15. Tracking of Drug Release and Material Fate for Naturally Derived Omega-3 Fatty Acid Biomaterials.

    Science.gov (United States)

    Faucher, Keith M; Artzi, Natalie; Beck, Moshe; Beckerman, Rita; Moodie, Geoff; Albergo, Theresa; Conroy, Suzanne; Dale, Alicia; Corbeil, Scott; Martakos, Paul; Edelman, Elazer R

    2016-03-01

    In vitro and in vivo studies were conducted on omega-3 fatty acid-derived biomaterials to determine their utility as an implantable material for adhesion prevention following soft tissue hernia repair and as a means to allow for the local delivery of antimicrobial or antibiofilm agents. Naturally derived biomaterials offer several advantages over synthetic materials in the field of medical device development. These advantages include enhanced biocompatibility, elimination of risks posed by the presence of toxic catalysts and chemical crosslinking agents, and derivation from renewable resources. Omega-3 fatty acids are readily available from fish and plant sources and can be used to create implantable biomaterials either as a stand-alone device or as a device coating that can be utilized in local drug delivery applications. In-depth characterization of material erosion degradation over time using non-destructive imaging and chemical characterization techniques provided mechanistic insight into material structure: function relationship. This in turn guided rational tailoring of the material based on varying fatty acid composition to control material residence time and hence drug release. These studies demonstrate the utility of omega-3 fatty acid derived biomaterials as an absorbable material for soft tissue hernia repair and drug delivery applications.

  16. Auspicious role of the steroidal heterocyclic derivatives as a platform for anti-cancer drugs.

    Science.gov (United States)

    Tantawy, Mohamed A; Nafie, Mohamed S; Elmegeed, Gamal A; Ali, Ibrahim A I

    2017-08-01

    Steroids are polycyclic compounds that have a wide range of biological activities. They are bio-synthesized from cholesterol through a series of enzyme-mediated transformations, so they are highly lipophilic and readily enter most cells to interact with intracellular receptors, making them ideal vehicles for targeting a broad array of pathologies. New curative agents for cancers have been developed from several steroidal derivatives. Some biologically important properties of modified steroids are dependent on structural features of the steroid moiety and their side chains. Therefore, chemical derivatization of steroids provides a way to modify their function, and many structure-activity relationships have been confirmed by such synthetic modifications. Several studies demonstrate that steroidal heterocyclic derivatives can be effective in the prevention and treatment of many types of hormone-dependent cancers. The present review is a concise report on steroidal heterocyclic derivatives, with special emphasis on steroid heterocyclic derivatives with 5 membered rings or six-membered rings having interesting therapeutic potential as enzyme inhibitors and cytotoxic drugs to be used as candidates for anti-cancer drug development. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. SucStruct: Prediction of succinylated lysine residues by using structural properties of amino acids.

    Science.gov (United States)

    López, Yosvany; Dehzangi, Abdollah; Lal, Sunil Pranit; Taherzadeh, Ghazaleh; Michaelson, Jacob; Sattar, Abdul; Tsunoda, Tatsuhiko; Sharma, Alok

    2017-06-15

    Post-Translational Modification (PTM) is a biological reaction which contributes to diversify the proteome. Despite many modifications with important roles in cellular activity, lysine succinylation has recently emerged as an important PTM mark. It alters the chemical structure of lysines, leading to remarkable changes in the structure and function of proteins. In contrast to the huge amount of proteins being sequenced in the post-genome era, the experimental detection of succinylated residues remains expensive, inefficient and time-consuming. Therefore, the development of computational tools for accurately predicting succinylated lysines is an urgent necessity. To date, several approaches have been proposed but their sensitivity has been reportedly poor. In this paper, we propose an approach that utilizes structural features of amino acids to improve lysine succinylation prediction. Succinylated and non-succinylated lysines were first retrieved from 670 proteins and characteristics such as accessible surface area, backbone torsion angles and local structure conformations were incorporated. We used the k-nearest neighbors cleaning treatment for dealing with class imbalance and designed a pruned decision tree for classification. Our predictor, referred to as SucStruct (Succinylation using Structural features), proved to significantly improve performance when compared to previous predictors, with sensitivity, accuracy and Mathew's correlation coefficient equal to 0.7334-0.7946, 0.7444-0.7608 and 0.4884-0.5240, respectively. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Hemoglobin Labeled by Radioactive Lysine

    Science.gov (United States)

    Bale, W. F.; Yuile, C. L.; DeLaVergne, L.; Miller, L. L.; Whipple, G. H.

    1949-12-08

    This paper reports on the utilization of tagged epsilon carbon of DL-lysine by a dog both anemic and hypoproteinemic due to repeated bleeding plus a diet low in protein. The experiment extended over period of 234 days, a time sufficient to indicate an erythrocyte life span of at least 115 days based upon the rate of replacement of labeled red cell proteins. The proteins of broken down red cells seem not to be used with any great preference for the synthesis of new hemoglobin.

  19. Synthesis and binding of [125I2]philanthotoxin-343, [125I2]philanthotoxin-343-lysine, and [125I2]philanthotoxin-343-arginine to rat brain membranes

    International Nuclear Information System (INIS)

    Goodnow, R.A. Jr.; Bukownik, R.; Nakanishi, K.; Usherwood, P.N.; Eldefrawi, A.T.; Anis, N.A.; Eldefrawi, M.E.

    1991-01-01

    125I2-iodinated philanthotoxin-343 (PhTX-343), [125I2]PhTX-343-arginine, and [125I2]PhTX-343-lysine were synthesized and evaluated as probes for glutamate receptors in rat brain synaptic membranes. It was found that these probes were not specific for the glutamate receptors but may be useful for investigating the polyamine binding site. Filtration assays with Whatman GF/B fiber glass filters were unsuitable because the iodinated PhTX-343 analogues exhibited high nonspecific binding to the filters, thus hindering detection of specific binding to membranes. When binding was measured by a centrifugal assay, [125I2]PhTX-343-lysine bound with low affinity (KD = 11.4 ± 2 microM) to a large number of sites (37.2 ± 9.1 nmol/mg of protein). The binding of [125I2]PhTX-343-lysine was sensitive only to the polyamines spermine and spermidine, which displaced [125I2]PhTX-343-lysine with Ki values of (3.77 ± 1.4) x 10(-5) M and (7.51 ± 0.77) x 10(-5) M, respectively. The binding was insensitive to glutamate receptor agonists and antagonists. Binding results with [125I2]PhTX-343-arginine were similar to those of [125I2]-PhTX-343-lysine. Considering the high number of toxin binding sites (10000-fold more than glutamate) in these membranes and the insensitivity of the binding to almost all drugs that bind to glutamate receptors, it is evident that most of the binding observed is not to glutamate receptors. On the other hand, PhTX analogues with photoaffinity labels may be useful in the isolation/purification of various glutamate and nicotinic acetylcholine receptors; they could also be useful in structural studies of receptors and their binding sites

  20. Effect of Selected Plant Extracts and D- and L-Lysine on the Cyanobacterium Microcystis aeruginosa

    NARCIS (Netherlands)

    Lurling, M.F.L.L.W.; Oosterhout, J.F.X.

    2014-01-01

    We tested extracts from Fructus mume, Salvia miltiorrhiza and Moringa oleifera as well as L-lysine and D-Lysine as curative measures to rapidly suppress the cyanobacterium Microcystis aeruginosa NIVA-CYA 43. We tested these compounds under similar conditions to facilitate comparisons. We

  1. Genetic analysis of diaminopimelic acid- and lysine-requiring mutants of Escherichia coli.

    Science.gov (United States)

    Bukhari, A I; Taylor, A L

    1971-03-01

    Several diaminopimelic acid (DAP)- and lysine-requiring mutants of Escherichia coli were isolated and studied by genetic, physiological, and biochemical means. The genes concerned with DAP-lysine synthesis map at several different sites on the E. coli chromosome and, therefore, do not constitute a single operon. Three separate loci affecting DAP synthesis are located in the 0 to 2.5 min region of the genetic map. The order of the loci in this region is thr-dapB-pyrA-ara-leu-pan-dapC-tonA-dapD. Two additional DAP genes map in the region between min 47 and 48, with the gene order being gua-dapA-dapE-ctr. The lys locus at min 55 determines the synthesis of the enzyme DAP decarboxylase, which catalyzes the conversion of DAP into lysine. The order of the genes in this region is serA-lysA-thyA.

  2. Exoproteome and Secretome Derived Broad Spectrum Novel Drug and Vaccine Candidates in Vibrio cholerae Targeted by Piper betel Derived Compounds

    Science.gov (United States)

    Barh, Debmalya; Barve, Neha; Gupta, Krishnakant; Chandra, Sudha; Jain, Neha; Tiwari, Sandeep; Leon-Sicairos, Nidia; Canizalez-Roman, Adrian; Rodrigues dos Santos, Anderson; Hassan, Syed Shah; Almeida, Síntia; Thiago Jucá Ramos, Rommel; Augusto Carvalho de Abreu, Vinicius; Ribeiro Carneiro, Adriana; de Castro Soares, Siomar; Luiz de Paula Castro, Thiago; Miyoshi, Anderson; Silva, Artur; Kumar, Anil; Narayan Misra, Amarendra; Blum, Kenneth; Braverman, Eric R.; Azevedo, Vasco

    2013-01-01

    Vibrio cholerae is the causal organism of the cholera epidemic, which is mostly prevalent in developing and underdeveloped countries. However, incidences of cholera in developed countries are also alarming. Because of the emergence of new drug-resistant strains, even though several generic drugs and vaccines have been developed over time, Vibrio infections remain a global health problem that appeals for the development of novel drugs and vaccines against the pathogen. Here, applying comparative proteomic and reverse vaccinology approaches to the exoproteome and secretome of the pathogen, we have identified three candidate targets (ompU, uppP and yajC) for most of the pathogenic Vibrio strains. Two targets (uppP and yajC) are novel to Vibrio, and two targets (uppP and ompU) can be used to develop both drugs and vaccines (dual targets) against broad spectrum Vibrio serotypes. Using our novel computational approach, we have identified three peptide vaccine candidates that have high potential to induce both B- and T-cell-mediated immune responses from our identified two dual targets. These two targets were modeled and subjected to virtual screening against natural compounds derived from Piper betel. Seven compounds were identified first time from Piper betel to be highly effective to render the function of these targets to identify them as emerging potential drugs against Vibrio. Our preliminary validation suggests that these identified peptide vaccines and betel compounds are highly effective against Vibrio cholerae. Currently we are exhaustively validating these targets, candidate peptide vaccines, and betel derived lead compounds against a number of Vibrio species. PMID:23382822

  3. Exoproteome and secretome derived broad spectrum novel drug and vaccine candidates in Vibrio cholerae targeted by Piper betel derived compounds.

    Directory of Open Access Journals (Sweden)

    Debmalya Barh

    Full Text Available Vibrio cholerae is the causal organism of the cholera epidemic, which is mostly prevalent in developing and underdeveloped countries. However, incidences of cholera in developed countries are also alarming. Because of the emergence of new drug-resistant strains, even though several generic drugs and vaccines have been developed over time, Vibrio infections remain a global health problem that appeals for the development of novel drugs and vaccines against the pathogen. Here, applying comparative proteomic and reverse vaccinology approaches to the exoproteome and secretome of the pathogen, we have identified three candidate targets (ompU, uppP and yajC for most of the pathogenic Vibrio strains. Two targets (uppP and yajC are novel to Vibrio, and two targets (uppP and ompU can be used to develop both drugs and vaccines (dual targets against broad spectrum Vibrio serotypes. Using our novel computational approach, we have identified three peptide vaccine candidates that have high potential to induce both B- and T-cell-mediated immune responses from our identified two dual targets. These two targets were modeled and subjected to virtual screening against natural compounds derived from Piper betel. Seven compounds were identified first time from Piper betel to be highly effective to render the function of these targets to identify them as emerging potential drugs against Vibrio. Our preliminary validation suggests that these identified peptide vaccines and betel compounds are highly effective against Vibrio cholerae. Currently we are exhaustively validating these targets, candidate peptide vaccines, and betel derived lead compounds against a number of Vibrio species.

  4. Energy and lysine requirements and balances of sows during transition and lactation: A factorial approach

    DEFF Research Database (Denmark)

    Feyera, Takele; Theil, Peter Kappel

    2017-01-01

    components (including uterus wall, placenta and membrane fluids) and maintenance were estimated. It was estimated that maintenance, additional heat loss, colostrum production, fetal growth, mammary growth and uterine components accounted for 66.8%, 19.3%, 7.2%, 5.0%, 1.3% and 0.5% of total ME requirements......, respectively, in the last 12 days of gestation. Oxidation/transamination, fetal growth, mammary growth, colostrum production, maintenance and uterine components were estimated to account for 29.5%, 22.7%, 16.8%, 16.1%, 10.4% and 4.5% of total SID lysine requirements, respectively, in the last 12 days...... of gestation. After parturition, ME and SID lysine requirements increased daily until peak lactation (day 17). At peak lactation, 95% and 72% of total required SID lysine and ME, respectively, were associated with milk production (including oxidation). Relative to day 104 of gestation, ME and SID lysine...

  5. Combinatorial Drug Testing in 3D Microtumors Derived from GBM Patient-Derived Xenografts Reveals Cytotoxic Synergy in Pharmacokinomics-informed Pathway Interactions.

    Science.gov (United States)

    Gilbert, Ashley N; Anderson, Joshua C; Duarte, Christine W; Shevin, Rachael S; Langford, Catherine P; Singh, Raj; Gillespie, G Yancey; Willey, Christopher D

    2018-05-30

    Glioblastoma multiforme (GBM), the most common form of primary malignant brain cancer in adults, is a devastating disease for which effective treatment has remained elusive for over 75 years. One reason for the minimal progress during this time is the lack of accurate preclinical models to represent the patient's tumor's in vivo environment, causing a disconnect in drug therapy effectiveness between the laboratory and clinic. While patient-derived xenografts (PDX's or xenolines) are excellent human tumor representations, they are not amenable to high throughput testing. Therefore, we developed a miniaturized xenoline system (microtumors) for drug testing. Nineteen GBM xenolines were profiled for global kinase (kinomic) activity revealing actionable kinase targets associated with intracranial tumor growth rate. Kinase inhibitors for these targets (WP1066, selumetinib, crizotinib, and cediranib) were selected for single and combination therapy using a fully human-derived three-dimensional (3D) microtumor model of GBM xenoline cells embedded in HuBiogel for subsequent molecular and phenotype assays. GBM microtumors closely resembled orthotopically-implanted tumors based on immunohistochemical analysis and displayed kinomic and morphological diversity. Drug response testing could be reproducibly performed in a 96-well format identifying several synergistic combinations. Our findings indicate that 3D microtumors can provide a suitable high-throughput model for combination drug testing.

  6. Sildenafil and tadalafil in simulated chlorination conditions: Ecotoxicity of drugs and their derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Temussi, Fabio; DellaGreca, Marina; Pistillo, Paola; Previtera, Lucio; Zarrelli, Armando [UdR Napoli 4 INCA, Dipartimento di Scienze Chimiche, Complesso Universitario di Monte Sant' Angelo, Università Federico II, Via Cintia, I-80126 Napoli (Italy); Criscuolo, Emma; Lavorgna, Margherita; Russo, Chiara [Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Seconda Università di Napoli, Via Vivaldi 43, I-81100 Caserta (Italy); Isidori, Marina, E-mail: marina.isidori@unina2.it [Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Seconda Università di Napoli, Via Vivaldi 43, I-81100 Caserta (Italy)

    2013-10-01

    Chlorination experiments on two drugs (sildenafil and tadalafil) were performed mimicking the conditions of a typical wastewater treatment process. The main transformation products were isolated by chromatographic techniques (Thin Layer Chromatography (TLC), Column Chromatography (CC), High Performance Liquid Chromatography (HPLC)) and fully characterized employing Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS) analyses. The environmental effects of the parent compounds and transformation products were evaluated using an overall toxicity approach that considered aquatic acute and chronic toxicity on Brachionus calyciflorus and Ceriodaphnia dubia as well as mutagenesis and genotoxicity on bacterial strains. The results revealed that both parent drugs did not show high acute and chronic toxicity for the organisms utilized in the bioassays while, chronic exposure to chlorine derivatives caused inhibition of growth population on rotifers and crustaceans. A mutagenic potential was found for all the compounds investigated. - Highlights: • Simulated disinfection process of pharmaceuticals was performed. • Toxicity and genotoxicity of sildenafil, tadalafil and their derivatives were evaluated. • Chlorine derivatives caused chronic toxicity on rotifers and crustaceans. • A mutagenic potential was found for all the compounds investigated.

  7. Histidine-lysine peptides as carriers of nucleic acids.

    Science.gov (United States)

    Leng, Qixin; Goldgeier, Lisa; Zhu, Jingsong; Cambell, Patricia; Ambulos, Nicholas; Mixson, A James

    2007-03-01

    With their biodegradability and diversity of permutations, peptides have significant potential as carriers of nucleic acids. This review will focus on the sequence and branching patterns of peptide carriers composed primarily of histidines and lysines. While lysines within peptides are important for binding to the negatively charged phosphates, histidines are critical for endosomal lysis enabling nucleic acids to reach the cytosol. Histidine-lysine (HK) polymers by either covalent or ionic bonds with liposomes augment transfection compared to liposome carriers alone. More recently, we have examined peptides as sole carriers of nucleic acids because of their intrinsic advantages compared to the bipartite HK/liposome carriers. With a protocol change and addition of a histidine-rich tail, HK peptides as sole carriers were more effective than liposomes alone in several cell lines. While four-branched polymers with a primary repeating sequence pattern of -HHK- were more effective as carriers of plasmids, eight-branched polymers with a sequence pattern of -HHHK- were more effective as carriers of siRNA. Compared to polyethylenimine, HK carriers of siRNA and plasmids had reduced toxicity. When injected intravenously, HK polymers in complex with plasmids encoding antiangiogenic proteins significantly decreased tumor growth. Furthermore, modification of HK polymers with polyethylene glycol and vascular-specific ligands increased specificity of the polyplex to the tumor by more than 40-fold. Together with further development and insight on the structure of HK polyplexes, HK peptides may prove to be useful as carriers of different forms of nucleic acids both in vitro and in vivo.

  8. Lysine metabolism in antisense C-hordein barley grains

    DEFF Research Database (Denmark)

    Schmidt, Daiana; Rizzi, Vanessa; Gaziola, Salete A

    2015-01-01

    The grain proteins of barley are deficient in lysine and threonine due to their low concentrations in the major storage protein class, the hordeins, especially in the C-hordein subgroup. Previously produced antisense C-hordein transgenic barley lines have an improved amino acid composition, with ...

  9. Effect of feeding three lysine to energy diets on growth, body composition and age at puberty in replacement gilts

    Science.gov (United States)

    This study evaluated the effect of diets differing in standard ileal digestible (SID) lysine on lysine intake, growth rate, body composition and age at puberty on maternal line gilts. Crossbred Large White×Landrace gilts (n =641) were fed corn-soybean diets differing in SID lysine concentration (%, ...

  10. Comparison of human myofibrillar protein catabolic rate derived from 3-methylhistidine excretion with synthetic rate from muscle biopsies during L-(. cap alpha. -/sup 15/N)lysine infusion

    Energy Technology Data Exchange (ETDEWEB)

    McKeran, R O; Halliday, D; Purkiss, P [Clinical Research Centre, Harrow (UK). Div. of Inherited Metabolic Diseases and Clinical Investigation

    1978-05-01

    Urine was collected in five healthy men over 10 to 14 days, with fasting blood samples on days 1, 5 and 10, whilst they consumed a standard creatine-free diet, which was quantitatively related to their body surface area. The urinary excretion of 3-methylhistidine fell to a plateau by day 5 in all subjects. Myofibrillar protein catabolic rate calculated from the mean value of 3-methylhistidine excretion from day 5 to day 10 averaged 1.21 g day/sup -1/ kg/sup -1/ body weight. The average turnover of muscle myofibrillar protein was calculated to be 2.16%/day. From a previous study using continuous intravenous infusion of L-(a-/sup 15/N)lysine with serial muscle biopsies on the same subjects, the mean myofibrillar protein synthetic rate was calculated to be 0.82 g day/sup -1/ kg/sup -1/ body weight, and the mean turnover rate was 1.47%/day of total muscle myofibrillar protein. The estimations of myofibrillar protein turnover rate derived from the two methods are compared and the differences discussed.

  11. Regulation of eukaryotic elongation factor 1 alpha (eEF1A) by dynamic lysine methylation

    DEFF Research Database (Denmark)

    Jakobsson, Magnus E; Małecki, Jędrzej; Falnes, Pål Ø

    2018-01-01

    Lysine methylation is a frequent post-translational protein modification, which has been intensively studied in the case of histone proteins. Lysine methylations are also found on many non-histone proteins, and one prominent example is eukaryotic elongation factor 1 alpha (eEF1A). Besides its...... essential role in the protein synthesis machinery, a number of non-canonical functions have also been described for eEF1A, such as regulation of the actin cytoskeleton and the promotion of viral replication. The functional significance of the extensive lysine methylations on eEF1A, as well as the identity...

  12. Report: Bioconversion of agriculture waste to lysine with UV mutated strain of brevibacterium flavum and its biological evaluation in broiler chicks.

    Science.gov (United States)

    Tabassum, Alia; Hashmi, Abu Saeed; Masood, Faiza; Iqbal, Muhammad Aamir; Tayyab, Muhammad; Nawab, Amber; Nadeem, Asif; Sadeghi, Zahra; Mahmood, Adeel

    2015-07-01

    Lysine executes imperative structural and functional roles in body and its supplementation in diet beneficial to prevent the escalating threat of protein deficiency. The physical mutagenesis offers new fascinating avenues of research for overproduction of lysine through surplus carbohydrate containing agriculture waste especially in developing countries. The current study was aimed to investigate the potential of UV mutated strain of Brevibacterium flavum at 254 nm for lysine production. The physical and nutritional parameters were optimized and maximum lysine production was observed with molasses (4% substrate water ratio). Moreover, supplementation of culture medium with metal cations (i.e. 0.4% CaSO₄, 0.3% NaCl, 0.3% KH₂PO₄, 0.4% MgSO₄, and 0.2% (NH₄) ₂SO₄w/v) together with 0.75% v/v corn steep liquor significantly enhanced the lysine production up to 26.71 ± 0.31 g/L. Though, concentrations of urea, ammonium nitrate and yeast sludge did not exhibit any profound effect on lysine production. Biological evaluation of lysine enriched biomass in terms of weight gain and feed conversion ratio reflected non-significant difference for experimental and control (+ve) groups. Conclusively, lysine produced in the form of biomass was compatible to market lysine in its effectiveness and have potential to utilize at commercial scale.

  13. Effect of Selected Plant Extracts and D- and L-Lysine on the Cyanobacterium Microcystis aeruginosa

    Directory of Open Access Journals (Sweden)

    Miquel Lürling

    2014-06-01

    Full Text Available We tested extracts from Fructus mume, Salvia miltiorrhiza and Moringa oleifera as well as L-lysine and D-Lysine as curative measures to rapidly suppress the cyanobacterium Microcystis aeruginosa NIVA-CYA 43. We tested these compounds under similar conditions to facilitate comparisons. We hypothesized that for each compound, relatively low concentrations—i.e., 5–50 mg L−1, would reduce M. aeruginosa biomass. At these low concentrations, only L-lysine caused a decline in M. aeruginosa biomass at ≥4.3 mg L−1. F. mume extract was effective to do so at high concentrations, i.e., at ≥240 mg L−1, but the others were virtually non-effective. Low pH caused by organic acids is a probable explanation for the effect of F. mume extract. No complete wipe-outs of the experimental population were achieved as Photosystem II efficiency showed a recovery after six days. L-lysine may be effective at low concentrations—meaning low material costs. However, the effect of L-lysine seems relatively short-lived. Overall, the results of our study did not support the use of the tested plant extracts and amino-acid as promising candidates for curative application in M. aeruginosa bloom control.

  14. Induced pluripotent stem cell-derived cardiomyocytes for cardiovascular disease modeling and drug screening

    OpenAIRE

    Sharma, Arun; Wu, Joseph C; Wu, Sean M

    2013-01-01

    Human induced pluripotent stem cells (hiPSCs) have emerged as a novel tool for drug discovery and therapy in cardiovascular medicine. hiPSCs are functionally similar to human embryonic stem cells (hESCs) and can be derived autologously without the ethical challenges associated with hESCs. Given the limited regenerative capacity of the human heart following myocardial injury, cardiomyocytes derived from hiPSCs (hiPSC-CMs) have garnered significant attention from basic and translational scienti...

  15. Impact of lysine-fortified wheat flour on morbidity and immunologic variables among members of rural families in northwest Syria.

    Science.gov (United States)

    Ghosh, Shibani; Pellett, Peter L; Aw-Hassan, Aden; Mouneime, Youssef; Smriga, Miro; Scrimshaw, Nevin S

    2008-09-01

    Previous studies have shown an effect of lysine fortification on nutrition and immunity of poor men, women, and children consuming a predominantly wheat-based diet. To examine the lysine value of diets and the effect of lysine fortification on functional protein status, anthropometry, and morbidity of men, women, and children in rural Syria. At baseline of a two-phase study using 7-day household food intake inventories (n = 98), nutrient availabilities per adult male equivalent were estimated. In the intervention phase, a 16-week double-blind trial, households (n = 106) were randomly assigned to control and lysine groups. Hematologic and anthropometric data were collected from men (n = 69; 31 control, 38 lysine), women (n = 99; 51 control, 48 lysine), and children (n = 69; 37 control, 32 lysine) at baseline, 12 weeks, and 16 weeks. Total CD3 T lymphocytes as well as T lymphocytes bearing the receptors CD4, CD8, and CD56, IgM, IgG, IgA, complement C3, C-reactive protein, serum albumin, prealbumin, transferrin, retinol-binding protein, hemoglobin, and hepatitis B surface antigen were determined. Health status and flour usage were monitored. Paired- and independent-sample t-tests and chi-square tests were performed. Mean nutrient availability per adult equivalent was 2,650 +/- 806 kcal, 70.1 +/- 26.4 g protein, 65 +/- 14% cereal protein, and 41.9 +/- 0.8 mg lysine per gram of protein. Complement C3 was significantly higher in men receiving lysine than in controls (p children, who have much higher morbidity and mortality rates from this disease than school-age children or adults.

  16. Proteomic Analysis of Lysine Acetylation Sites in Rat Tissues Reveals Organ Specificity and Subcellular Patterns

    Directory of Open Access Journals (Sweden)

    Alicia Lundby

    2012-08-01

    Full Text Available Lysine acetylation is a major posttranslational modification involved in a broad array of physiological functions. Here, we provide an organ-wide map of lysine acetylation sites from 16 rat tissues analyzed by high-resolution tandem mass spectrometry. We quantify 15,474 modification sites on 4,541 proteins and provide the data set as a web-based database. We demonstrate that lysine acetylation displays site-specific sequence motifs that diverge between cellular compartments, with a significant fraction of nuclear sites conforming to the consensus motifs G-AcK and AcK-P. Our data set reveals that the subcellular acetylation distribution is tissue-type dependent and that acetylation targets tissue-specific pathways involved in fundamental physiological processes. We compare lysine acetylation patterns for rat as well as human skeletal muscle biopsies and demonstrate its general involvement in muscle contraction. Furthermore, we illustrate that acetylation of fructose-bisphosphate aldolase and glycerol-3-phosphate dehydrogenase serves as a cellular mechanism to switch off enzymatic activity.

  17. Aspects of the selection, design and use of high lysine cereals

    International Nuclear Information System (INIS)

    Munck, L.

    1976-01-01

    A discussion of the need for and the considerations involved in the breeding of high lysine cereals is presented. Progress in the discovery and exploitation of genotypes with high lysine characters in maize and barley are briefly reviewed. The role and some of the characteristics of the dye-binding capacity (DBC) methods are evaluated along with the ways in which DBC results should be used in combination with other information. Lastly, the changes in attitudes and procedures associated with the acceptance of a product of a new technology such as nutritionally improved cereals is discussed. (author)

  18. Effect of different levels of lysine in the diet of broilers on the metabolism of /sup 35/S-methionine

    Energy Technology Data Exchange (ETDEWEB)

    Stanchev, Kh; Venkov, T; Dzharova, M [Akademiya na Selskostopanskite Nauki, Sofia-Kostinbrod (Bulgaria). Inst. po Zhivotnovydstvo

    1974-01-01

    The lack of balance of the ration with respect to lysine leads to a decrease in the rate of incorporation of /sup 35/S-methionine in the liver, pancreas, kidney and femoral muscle. Most intensive protein synthesis in the liver of chickens is observed in the group receiving ration balanced with respect to lysine while in the case of a deficiency or excess of lysine the protein biosynthesis drops. The deficiency or excess of lysine leads to an increase in the excretion rate and decreases the assimilability of radioactive methionine in the chickens organisms. (INIS)

  19. Low dose tubulin-binding drugs rescue peroxisome trafficking deficit in patient-derived stem cells in Hereditary Spastic Paraplegia

    Directory of Open Access Journals (Sweden)

    Yongjun Fan

    2014-05-01

    Full Text Available Hereditary Spastic Paraplegia (HSP is a genetically heterogeneous group of disorders, diagnosed by progressive gait disturbances with muscle weakness and spasticity, for which there are no treatments targeted at the underlying pathophysiology. Mutations in spastin are a common cause of HSP. Spastin is a microtubule-severing protein whose mutation in mouse causes defective axonal transport. In human patient-derived olfactory neurosphere-derived (ONS cells, spastin mutations lead to lower levels of acetylated α-tubulin, a marker of stabilised microtubules, and to slower speed of peroxisome trafficking. Here we screened multiple concentrations of four tubulin-binding drugs for their ability to rescue levels of acetylated α-tubulin in patient-derived ONS cells. Drug doses that restored acetylated α-tubulin to levels in control-derived ONS cells were then selected for their ability to rescue peroxisome trafficking deficits. Automated microscopic screening identified very low doses of the four drugs (0.5 nM taxol, 0.5 nM vinblastine, 2 nM epothilone D, 10 µM noscapine that rescued acetylated α-tubulin in patient-derived ONS cells. These same doses rescued peroxisome trafficking deficits, restoring peroxisome speeds to untreated control cell levels. These results demonstrate a novel approach for drug screening based on high throughput automated microscopy for acetylated α-tubulin followed by functional validation of microtubule-based peroxisome transport. From a clinical perspective, all the drugs tested are used clinically, but at much higher doses. Importantly, epothilone D and noscapine can enter the central nervous system, making them potential candidates for future clinical trials.

  20. Low dose tubulin-binding drugs rescue peroxisome trafficking deficit in patient-derived stem cells in Hereditary Spastic Paraplegia

    Science.gov (United States)

    Fan, Yongjun; Wali, Gautam; Sutharsan, Ratneswary; Bellette, Bernadette; Crane, Denis I.; Sue, Carolyn M.; Mackay-Sim, Alan

    2014-01-01

    ABSTRACT Hereditary Spastic Paraplegia (HSP) is a genetically heterogeneous group of disorders, diagnosed by progressive gait disturbances with muscle weakness and spasticity, for which there are no treatments targeted at the underlying pathophysiology. Mutations in spastin are a common cause of HSP. Spastin is a microtubule-severing protein whose mutation in mouse causes defective axonal transport. In human patient-derived olfactory neurosphere-derived (ONS) cells, spastin mutations lead to lower levels of acetylated α-tubulin, a marker of stabilised microtubules, and to slower speed of peroxisome trafficking. Here we screened multiple concentrations of four tubulin-binding drugs for their ability to rescue levels of acetylated α-tubulin in patient-derived ONS cells. Drug doses that restored acetylated α-tubulin to levels in control-derived ONS cells were then selected for their ability to rescue peroxisome trafficking deficits. Automated microscopic screening identified very low doses of the four drugs (0.5 nM taxol, 0.5 nM vinblastine, 2 nM epothilone D, 10 µM noscapine) that rescued acetylated α-tubulin in patient-derived ONS cells. These same doses rescued peroxisome trafficking deficits, restoring peroxisome speeds to untreated control cell levels. These results demonstrate a novel approach for drug screening based on high throughput automated microscopy for acetylated α-tubulin followed by functional validation of microtubule-based peroxisome transport. From a clinical perspective, all the drugs tested are used clinically, but at much higher doses. Importantly, epothilone D and noscapine can enter the central nervous system, making them potential candidates for future clinical trials. PMID:24857849

  1. Pharmacokinetics of lysine clonixinate in children in postoperative care.

    Science.gov (United States)

    González-Martin, G; Cattan, C; Zuñiga, S

    1996-09-01

    The pharmacokinetics of 2 doses of intravenous lysine clonixinate (4 and 6 mg x kg-1) were studied in 10 children (age 4-10 years) under postoperative care. A single dose of the drug was injected in a forearm vein. Blood samples were collected at regular intervals for 3 hours. Serum clonixin concentrations (expressed as clonixin) were analyzed using a high pressure liquid chromatography method. Pharmacokinetic values were estimated by a nonlinear computer program. The distribution volume was similar in both groups of children (1.288 +/- 0.829 1 and 1. 139 +/- 0.667 1, respectively). There were no differences between the values of total plasma clearance and the administered doses (0.026 +/- 0.017 ml x min-1 and 0.017 +/- 0.008 ml x min-1, t = 1.07, p = 0.76). The elimination half-life was longer in children who received 6 mg x kg-1 (44.26 +/- 6.34 min vs 38.63 +/- 10.93 min) but this difference was not statistically significant (t = 0.99, p < 0.34). The pharmacokinetic parameters calculated in these children were different from those found by other authors in adults and experimental animals.

  2. Acid dissociation constant and apparent nucleophilicity of lysine-501 of the alpha-polypeptide of sodium and potassium ion activated adenosinetriphosphatase

    International Nuclear Information System (INIS)

    Xu, K.Y.

    1989-01-01

    A combination of competitive labeling with [ 3 H]acetic anhydride and immunoaffinity chromatography is described that permits the assignment of the acid dissociation constant and the absolute nucleophilicity of individual lysines in a native enzyme. The acid dissociation constant of lysine-501 of the alpha-polypeptide in native (Na+ + K+)-ATPase was determined. This lysine had a normal pKa of 10.4. The rate constant for the reaction of the free base of lysine-501 with acetic anhydride at 10 degrees C is 400 M-1 s-1. This value is only 30% that for a fully accessible lysine in a protein. The lower than normal apparent nucleophilicity suggests that lysine-501 is hindered from reacting with its intrinsic nucleophilicity by the tertiary structure of the enzyme and is consistent with its location within a pocket that forms the active site upon the surface of the native protein

  3. Brain-derived neurotrophic factor and addiction: Pathological versus therapeutic effects on drug seeking

    NARCIS (Netherlands)

    Barker, J.M.; Taylor, J.R.; de Vries, T.J.; Peters, J.

    2015-01-01

    Many abused drugs lead to changes in endogenous brain-derived neurotrophic factor (BDNF) expression in neural circuits responsible for addictive behaviors. BDNF is a known molecular mediator of memory consolidation processes, evident at both behavioral and neurophysiological levels. Specific neural

  4. Pharmacokinetic drug interactions of morphine, codeine, and their derivatives: theory and clinical reality, part I.

    Science.gov (United States)

    Armstrong, Scott C; Cozza, Kelly L

    2003-01-01

    Pharmacokinetic drug-drug interactions with morphine, hydromorphone, and oxymorphone are reviewed in this column. Morphine is a naturally occurring opiate that is metabolized chiefly through glucuronidation by uridine diphosphate glucuronosyl transferase (UGT) enzymes in the liver. These enzymes produce an active analgesic metabolite and a potentially toxic metabolite. In vivo drug-drug interaction studies with morphine are few, but they do suggest that inhibition or induction of UGT enzymes could alter morphine and its metabolite levels. These interactions could change analgesic efficacy. Hydromorphone and oxymorphone, close synthetic derivatives of morphine, are also metabolized primarily by UGT enzymes. Hydromorphone may have a toxic metabolite similar to morphine. In vivo drug-drug interaction studies with hydromorphone and oxymorphone have not been done, so it is difficult to make conclusions with these drugs.

  5. Antibacterial activity of a newly developed peptide-modified lysin against Acinetobacter baumannii and Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Hang eYang

    2015-12-01

    Full Text Available The global emergence of multidrug-resistant (MDR bacteria is a growing threat to public health worldwide. Natural bacteriophage lysins are promising alternatives in the treatment of infections caused by Gram-positive pathogens, but not Gram-negative ones, like Acinetobacter baumannii and Pseudomonas aeruginosa, due to the barriers posed by their outer membranes. Recently, modifying a natural lysin with an antimicrobial peptide was found able to break the barriers, and to kill Gram-negative pathogens. Herein, a new peptide-modified lysin (PlyA was constructed by fusing the cecropin A peptide residues 1–8 (KWKLFKKI with the OBPgp279 lysin and its antibacterial activity was studied. PlyA showed good and broad antibacterial activities against logarithmic phase A. baumannii and P. aeruginosa, but much reduced activities against the cells in stationary phase. Addition of outer membrane permeabilizers (EDTA and citric acid could enhance the antibacterial activity of PlyA against stationary phase cells. Finally, no antibacterial activity of PlyA could be observed in some bio-matrices, such as culture media, milk, and sera. In conclusion, we reported here a novel peptide-modified lysin with significant antibacterial activity against both logarithmic (without OMPs and stationary phase (with OMPs A. baumannii and P. aeruginosa cells in buffer, but further optimization is needed to achieve broad activity in diverse bio-matrices.

  6. Induction of monooxygenases and incorporation of radioactivity from 2-14C-lysine into hepatic microsomes of phenobarbital-treated rats fed a diet deficient in lysine, methionine, threonine and vitamine A, C and E

    International Nuclear Information System (INIS)

    Nurmagambetov, T.Zh.; Amirov, B.B.; Kuanysheva, T.K.; Sharmanov, T.Sh.

    1991-01-01

    The effect of diet on induction of monooxygenases and distribution of label from 2- 14 C-lysine in fractions of liver homogenate, muscle homogenate and blood of male rats treated with phenobarbital (80 mg/rg, three days) was studied. 2- 14 C-lysine was injected intraperitoneally 24 h before the first injection of phenobarbital. It was demonstrated that monooxygenase induction, increase of relative liver weight and incorporation of label from 2- 14 C-lysine into fractions of liver homogenate in phenobarbital-treated rats were more pronounced as compared with the similarly trated rats that were fed a balanced diet. The possibility of mobilization of deficient essential components to liver from other organs and tissues for maintenance of monooxygenase induction is discussed

  7. Toxins and derivatives in molecular pharmaceutics: Drug delivery and targeted therapy.

    Science.gov (United States)

    Zhan, Changyou; Li, Chong; Wei, Xiaoli; Lu, Wuyuan; Lu, Weiyue

    2015-08-01

    Protein and peptide toxins offer an invaluable source for the development of actively targeted drug delivery systems. They avidly bind to a variety of cognate receptors, some of which are expressed or even up-regulated in diseased tissues and biological barriers. Protein and peptide toxins or their derivatives can act as ligands to facilitate tissue- or organ-specific accumulation of therapeutics. Some toxins have evolved from a relatively small number of structural frameworks that are particularly suitable for addressing the crucial issues of potency and stability, making them an instrumental source of leads and templates for targeted therapy. The focus of this review is on protein and peptide toxins for the development of targeted drug delivery systems and molecular therapies. We summarize disease- and biological barrier-related toxin receptors, as well as targeted drug delivery strategies inspired by those receptors. The design of new therapeutics based on protein and peptide toxins is also discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. protein, tryptophan and lysine contents in quality protien maize

    African Journals Online (AJOL)

    owner

    From the human nutrition view point, lysine is the ... latitude and 79.3°E longitude and at an altitude of ... transferred to boiling tubes. ... mixtures were heated until the color changes to ... water was added into the digestion tube carefully.

  9. Herb–drug interaction prediction based on the high specific inhibition of andrographolide derivatives towards UDP-glucuronosyltransferase (UGT) 2B7

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Hai-Ying [The Fourth Affiliated Hospital of China Medical University, Shenyang 110032 (China); Sun, Dong-Xue [School of Traditional Chinese Medicine, Shenyang Pharmaceutical University, No. 103, Wenhua Road, Shenyang 110016 (China); Cao, Yun-Feng [The First Affiliated Hospital of Liaoning Medical University, Jinzhou 121001 (China); Joint Center for Translational Medicine, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road, Dalian 116023 (China); Ai, Chun-Zhi [Joint Center for Translational Medicine, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road, Dalian 116023 (China); Qu, Yan-Qing [Thyroid Surgery, Yantaishan Hospital, Yantai, Shandong (China); Hu, Cui-Min [Joint Center for Translational Medicine, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road, Dalian 116023 (China); Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057 (United States); Jiang, Changtao [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892 (United States); Dong, Pei-Pei [Academy of Integrative Medicine, Dalian Medical University, Dalian 116044 (China); Sun, Xiao-Yu; Hong, Mo [Joint Center for Translational Medicine, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road, Dalian 116023 (China); Tanaka, Naoki; Gonzalez, Frank J. [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892 (United States); others, and

    2014-05-15

    Herb–drug interaction strongly limits the clinical application of herbs and drugs, and the inhibition of herbal components towards important drug-metabolizing enzymes (DMEs) has been regarded as one of the most important reasons. The present study aims to investigate the inhibition potential of andrographolide derivatives towards one of the most important phase II DMEs UDP-glucuronosyltransferases (UGTs). Recombinant UGT isoforms (except UGT1A4)-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction and UGT1A4-catalyzed trifluoperazine (TFP) glucuronidation were employed to firstly screen the andrographolide derivatives' inhibition potential. High specific inhibition of andrographolide derivatives towards UGT2B7 was observed. The inhibition type and parameters (K{sub i}) were determined for the compounds exhibiting strong inhibition capability towards UGT2B7, and human liver microsome (HLMs)-catalyzed zidovudine (AZT) glucuronidation probe reaction was used to furtherly confirm the inhibition behavior. In combination of inhibition parameters (K{sub i}) and in vivo concentration of andrographolide and dehydroandrographolide, the potential in vivo inhibition magnitude was predicted. Additionally, both the in vitro inhibition data and computational modeling results provide important information for the modification of andrographolide derivatives as selective inhibitors of UGT2B7. Taken together, data obtained from the present study indicated the potential herb–drug interaction between Andrographis paniculata and the drugs mainly undergoing UGT2B7-catalyzed metabolic elimination, and the andrographolide derivatives as potential candidates for the selective inhibitors of UGT2B7. - Highlights: • Specific inhibition of andrographolide derivatives towards UGT2B7. • Herb-drug interaction related withAndrographis paniculata. • Guidance for design of UGT2B7 specific inhibitors.

  10. Herb–drug interaction prediction based on the high specific inhibition of andrographolide derivatives towards UDP-glucuronosyltransferase (UGT) 2B7

    International Nuclear Information System (INIS)

    Ma, Hai-Ying; Sun, Dong-Xue; Cao, Yun-Feng; Ai, Chun-Zhi; Qu, Yan-Qing; Hu, Cui-Min; Jiang, Changtao; Dong, Pei-Pei; Sun, Xiao-Yu; Hong, Mo; Tanaka, Naoki; Gonzalez, Frank J.

    2014-01-01

    Herb–drug interaction strongly limits the clinical application of herbs and drugs, and the inhibition of herbal components towards important drug-metabolizing enzymes (DMEs) has been regarded as one of the most important reasons. The present study aims to investigate the inhibition potential of andrographolide derivatives towards one of the most important phase II DMEs UDP-glucuronosyltransferases (UGTs). Recombinant UGT isoforms (except UGT1A4)-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction and UGT1A4-catalyzed trifluoperazine (TFP) glucuronidation were employed to firstly screen the andrographolide derivatives' inhibition potential. High specific inhibition of andrographolide derivatives towards UGT2B7 was observed. The inhibition type and parameters (K i ) were determined for the compounds exhibiting strong inhibition capability towards UGT2B7, and human liver microsome (HLMs)-catalyzed zidovudine (AZT) glucuronidation probe reaction was used to furtherly confirm the inhibition behavior. In combination of inhibition parameters (K i ) and in vivo concentration of andrographolide and dehydroandrographolide, the potential in vivo inhibition magnitude was predicted. Additionally, both the in vitro inhibition data and computational modeling results provide important information for the modification of andrographolide derivatives as selective inhibitors of UGT2B7. Taken together, data obtained from the present study indicated the potential herb–drug interaction between Andrographis paniculata and the drugs mainly undergoing UGT2B7-catalyzed metabolic elimination, and the andrographolide derivatives as potential candidates for the selective inhibitors of UGT2B7. - Highlights: • Specific inhibition of andrographolide derivatives towards UGT2B7. • Herb-drug interaction related withAndrographis paniculata. • Guidance for design of UGT2B7 specific inhibitors

  11. Herb–drug interaction prediction based on the high specific inhibition of andrographolide derivatives towards UDP-glucuronosyltransferase (UGT) 2B7

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Hai-Ying, E-mail: cmu4h-mhy@126.com [The Fourth Affiliated Hospital of China Medical University, Shenyang 110032 (China); Sun, Dong-Xue [School of Traditional Chinese Medicine, Shenyang Pharmaceutical University, No. 103, Wenhua Road, Shenyang 110016 (China); Cao, Yun-Feng [The First Affiliated Hospital of Liaoning Medical University, Jinzhou 121001 (China); Joint Center for Translational Medicine, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road, Dalian 116023 (China); Ai, Chun-Zhi [Joint Center for Translational Medicine, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road, Dalian 116023 (China); Qu, Yan-Qing [Thyroid Surgery, Yantaishan Hospital, Yantai, Shandong (China); Hu, Cui-Min [Joint Center for Translational Medicine, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road, Dalian 116023 (China); Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057 (United States); Jiang, Changtao [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892 (United States); Dong, Pei-Pei [Academy of Integrative Medicine, Dalian Medical University, Dalian 116044 (China); Sun, Xiao-Yu; Hong, Mo [Joint Center for Translational Medicine, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road, Dalian 116023 (China); Tanaka, Naoki; Gonzalez, Frank J. [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892 (United States); and others

    2014-05-15

    Herb–drug interaction strongly limits the clinical application of herbs and drugs, and the inhibition of herbal components towards important drug-metabolizing enzymes (DMEs) has been regarded as one of the most important reasons. The present study aims to investigate the inhibition potential of andrographolide derivatives towards one of the most important phase II DMEs UDP-glucuronosyltransferases (UGTs). Recombinant UGT isoforms (except UGT1A4)-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction and UGT1A4-catalyzed trifluoperazine (TFP) glucuronidation were employed to firstly screen the andrographolide derivatives' inhibition potential. High specific inhibition of andrographolide derivatives towards UGT2B7 was observed. The inhibition type and parameters (K{sub i}) were determined for the compounds exhibiting strong inhibition capability towards UGT2B7, and human liver microsome (HLMs)-catalyzed zidovudine (AZT) glucuronidation probe reaction was used to furtherly confirm the inhibition behavior. In combination of inhibition parameters (K{sub i}) and in vivo concentration of andrographolide and dehydroandrographolide, the potential in vivo inhibition magnitude was predicted. Additionally, both the in vitro inhibition data and computational modeling results provide important information for the modification of andrographolide derivatives as selective inhibitors of UGT2B7. Taken together, data obtained from the present study indicated the potential herb–drug interaction between Andrographis paniculata and the drugs mainly undergoing UGT2B7-catalyzed metabolic elimination, and the andrographolide derivatives as potential candidates for the selective inhibitors of UGT2B7. - Highlights: • Specific inhibition of andrographolide derivatives towards UGT2B7. • Herb-drug interaction related withAndrographis paniculata. • Guidance for design of UGT2B7 specific inhibitors.

  12. Deregulation of histone lysine methyltransferases contributes to oncogenic transformation of human bronchoepithelial cells

    Directory of Open Access Journals (Sweden)

    Yoda Satoshi

    2008-11-01

    Full Text Available Abstract Background Alterations in the processing of the genetic information in carcinogenesis result from stable genetic mutations or epigenetic modifications. It is becoming clear that nucleosomal histones are central to proper gene expression and that aberrant DNA methylation of genes and histone methylation plays important roles in tumor progression. To date, several histone lysine methyltransferases (HKMTs have been identified and histone lysine methylation is now considered to be a critical regulator of transcription. However, still relatively little is known about the role of HKMTs in tumorigenesis. Results We observed differential HKMT expression in a lung cancer model in which normal human bronchial epithelial (NHBE cells expressing telomerase, SV40 large T antigen, and Ras were immortal, formed colonies in soft agar, and expressed specific HKMTs for H3 lysine 9 and 27 residues but not for H3 lysine 4 residue. Modifications in the H3 tails affect the binding of proteins to the histone tails and regulate protein function and the position of lysine methylation marks a gene to be either activated or repressed. In the present study, suppression by siRNA of HKMTs (EZH2, G9A, SETDB1 and SUV39H1 that are over-expressed in immortalized and transformed cells lead to reduced cell proliferation and much less anchorage-independent colony growth. We also found that the suppression of H3-K9, G9A and SUV39H1 induced apoptosis and the suppression of H3-K27, EZH2 caused G1 arrest. Conclusion Our results indicate the potential of these HKMTs in addition to the other targets for epigenetics such as DNMTs and HDACs to be interesting therapeutic targets.

  13. [Studies with 15N-labeled lysine in colostomized hens. 2. 15N excretion in feces].

    Science.gov (United States)

    Gruhn, K; Wiefel, P

    1983-05-01

    Over a period of four days colostomised hens were given 15N-lysine, and the development of 15N-excretion both in the TCA-soluble and the TCA-precipitable fraction of the faeces was measured over eight days. In both fractions the total, lysine, histidine and arginine N and 15N-excess (15N') was determined. The average apparent digestibility of 14N was 81.2% +/- 1.1% and of 15N' 93.2% +/- 0.7%. Labelled N is already excreted in faeces 3 hours after its application. The TCA-precipitable N is less strongly labelled than the TCA-soluble N. During the application of 15N' the labelling in faecal lysine is nearly one power of ten higher than in total N. The atom-% 15N' of the lysine could also be distinctly detected in arginine and histidine. The quotas of the total 15N' in faeces were 3.5% for arginine-15N' and 0.8% for histidine 15N'; 15N' can mainly be detected in the soluble fraction.

  14. Effect of low protein diets and lysine supplementation on growth ...

    African Journals Online (AJOL)

    Dr. Ajit

    2012-07-17

    Jul 17, 2012 ... 3Division of Livestock Product Technology, Indian Veterinary Research Institute, Izatnagar – 243 ... Key words: Carcass trait, low protein, lysine, meat quality, pigs. ... functional activities, reproduction and disease resistance.

  15. A Toolbox of Genetically Encoded FRET-Based Biosensors for Rapid l-Lysine Analysis

    Directory of Open Access Journals (Sweden)

    Victoria Steffen

    2016-09-01

    Full Text Available Background: The fast development of microbial production strains for basic and fine chemicals is increasingly carried out in small scale cultivation systems to allow for higher throughput. Such parallelized systems create a need for new rapid online detection systems to quantify the respective target compound. In this regard, biosensors, especially genetically encoded Förster resonance energy transfer (FRET-based biosensors, offer tremendous opportunities. As a proof-of-concept, we have created a toolbox of FRET-based biosensors for the ratiometric determination of l-lysine in fermentation broth. Methods: The sensor toolbox was constructed based on a sensor that consists of an optimized central lysine-/arginine-/ornithine-binding protein (LAO-BP flanked by two fluorescent proteins (enhanced cyan fluorescent protein (ECFP, Citrine. Further sensor variants with altered affinity and sensitivity were obtained by circular permutation of the binding protein as well as the introduction of flexible and rigid linkers between the fluorescent proteins and the LAO-BP, respectively. Results: The sensor prototype was applied to monitor the extracellular l-lysine concentration of the l-lysine producing Corynebacterium glutamicum (C. glutamicum strain DM1933 in a BioLector® microscale cultivation device. The results matched well with data obtained by HPLC analysis and the Ninhydrin assay, demonstrating the high potential of FRET-based biosensors for high-throughput microbial bioprocess optimization.

  16. Forfeiture of the profits and proceeds derived from drug trafficking: thoughts on future action in Malaysia.

    Science.gov (United States)

    Vohrah, K C

    1984-01-01

    While the Dangerous Drugs Act 1952 of Malaysia has been amended to take into account changing patterns of drug abuse and trafficking, it lacks provisions for the mandatory forfeiture of proceeds derived from drug trafficking. Nor do the general powers of forfeiture in the Criminal Procedure Code of the country extend to such proceeds. To meet further changing patterns of drug trafficking involving criminal syndicate leaders, who rarely incriminate themselves through overt and detectable acts, Malaysia has a bill in Parliament the purpose of which, when it becomes law, is to detain without trial, upon cogent evidence, persons who have been associated with any activity relating to or involving drug trafficking, and to prevent them from further committing drug crimes. In addition, serious thinking has been given to the possibility of adopting, within the constraints of the Malaysian Constitution, a law on forfeiture of the proceeds derived from drug trafficking. There are, in this respect, several problems to be resolved, such as the secrecy of bank accounts and taxpayers' returns, which might make it difficult to trace proceeds and to keep track of tainted money being remitted abroad, although it is believed that such problems could be overcome by domestic measures. A more serious problem is the lack of international co-operation for investigations to be carried out outside national borders to trace, seize, freeze and secure the forfeiture of the proceeds of drug crimes located abroad.

  17. Overexpression of wild-type aspartokinase increases L-lysine production in the thermotolerant methylotrophic bacterium Bacillus methanolicus.

    Science.gov (United States)

    Jakobsen, Oyvind M; Brautaset, Trygve; Degnes, Kristin F; Heggeset, Tonje M B; Balzer, Simone; Flickinger, Michael C; Valla, Svein; Ellingsen, Trond E

    2009-02-01

    Aspartokinase (AK) controls the carbon flow into the aspartate pathway for the biosynthesis of the amino acids l-methionine, l-threonine, l-isoleucine, and l-lysine. We report here the cloning of four genes (asd, encoding aspartate semialdehyde dehydrogenase; dapA, encoding dihydrodipicolinate synthase; dapG, encoding AKI; and yclM, encoding AKIII) of the aspartate pathway in Bacillus methanolicus MGA3. Together with the known AKII gene lysC, dapG and yclM form a set of three AK genes in this organism. Overexpression of dapG, lysC, and yclM increased l-lysine production in wild-type B. methanolicus strain MGA3 2-, 10-, and 60-fold (corresponding to 11 g/liter), respectively, without negatively affecting the specific growth rate. The production levels of l-methionine (less than 0.5 g/liter) and l-threonine (less than 0.1 g/liter) were low in all recombinant strains. The AK proteins were purified, and biochemical analyses demonstrated that they have similar V(max) values (between 47 and 58 micromol/min/mg protein) and K(m) values for l-aspartate (between 1.9 and 5.0 mM). AKI and AKII were allosterically inhibited by meso-diaminopimelate (50% inhibitory concentration [IC(50)], 0.1 mM) and by l-lysine (IC(50), 0.3 mM), respectively. AKIII was inhibited by l-threonine (IC(50), 4 mM) and by l-lysine (IC(50), 5 mM), and this enzyme was synergistically inhibited in the presence of both of these amino acids at low concentrations. The correlation between the impact on l-lysine production in vivo and the biochemical properties in vitro of the individual AK proteins is discussed. This is the first example of improving l-lysine production by metabolic engineering of B. methanolicus and also the first documentation of considerably increasing l-lysine production by overexpression of a wild-type AK.

  18. Systematic replacement of lysine with glutamine and alanine in Escherichia coli malate synthase G: effect on crystallization

    International Nuclear Information System (INIS)

    Anstrom, David M.; Colip, Leslie; Moshofsky, Brian; Hatcher, Eric; Remington, S. James

    2005-01-01

    Alanine and glutamine mutations were made to the same 15 lysine positions on the surface of E. coli malate synthase G and the impact on crystallization observed. The results support lysine replacement for improvement of crystallization and provide insight into site selection and type of amino-acid replacement. Two proposals recommend substitution of surface lysine residues as a means to improve the quality of protein crystals. In proposal I, substitution of lysine by alanine has been suggested to improve crystallization by reducing the entropic cost of ordering flexible side chains at crystal contacts. In proposal II, substitution of lysine by residues more commonly found in crystal contacts, such as glutamine, has been proposed to improve crystallization. 15 lysine residues on the surface of Escherichia coli malate synthase G, distributed over a variety of secondary structures, were individually mutated to both alanine and glutamine. For 28 variants, detailed studies of the effect on enzymatic activity and crystallization were conducted. This has permitted direct comparison of the relative effects of the two types of mutations. While none of the variants produced crystals suitable for X-ray structural determination, small crystals were obtained in a wide variety of conditions, in support of the general approach. Glutamine substitutions were found to be more effective than alanine in producing crystals, in support of proposal II. Secondary structure at the site of mutation does not appear to play a major role in determining the rate of success

  19. Nanoparticles as Antituberculosis Drugs Carriers: Effect on Activity Against Mycobacterium tuberculosis in Human Monocyte-Derived Macrophages

    International Nuclear Information System (INIS)

    Anisimova, Y.V.; Gelperina, S.I.; Peloquin, C.A.; Heifets, L.B.

    2000-01-01

    This is the first report evaluating the nanoparticle delivery system for three antituberculosis drugs: isoniazid, rifampin, and streptomycin. The typical particle size is 250 nm. We studied accumulation of these drugs in human monocytes as well as their antimicrobial activity against Mycobacterium tuberculosis residing in human monocyte-derived macrophages. Nanoparticle encapsulation increased the intracellular accumulation (cell-association) of all three tested drugs, but it enhanced the antimicrobial activity of isoniazid and streptomycin only. On the other hand, the activity of encapsulated rifampin against intracellular bacteria was not higher than that of the free drug

  20. Lysine and glutamate transport in the erythrocytes of common brushtail possum, Tammar Wallaby and eastern grey, kangaroo.

    Science.gov (United States)

    Ogawa, E; Kuchel, P W; Agar, N S

    1998-04-01

    It was recently coincidentally discovered, using 1H NMR spectroscopy, that the erythrocytes of two species of Australian marsupials, Tammar Wallaby (Macropus eugenii) and Bettong (Bettongia penicillata), contain relatively high concentrations of the essential amino acid lysine (Agar NS, Rae CD, Chapman BE, Kuchel PW. Comp Biochem Physiol 1991;99B:575-97). Hence, in the present work the rates of transport of lysine into the erythrocytes from the Common Brushtail Possum (Dactylopsilia trivirgata) and Eastern Grey Kangaroo (Macropus giganteus) (which both have low lysine concentrations), and Tammar Wallaby were studied, to explore the mechanistic basis of this finding. The concentration-dependence of the uptake was studied with lysine alone and in the presence of arginine, which may be a competitor of the transport in some species. In relation to GSH metabolism, glutamate uptake was determined in the presence and absence of Na+. The data was analysed to yield estimates of the maximal velocity (Vmax) and the Km in each of the species. Erythrocytes from Tammar Wallaby lacked saturable lysine transport in contrast to the other two species. The glutamate uptake was normal in all three animals for adequate GSH biosynthesis.

  1. Ribosomes slide on lysine-encoding homopolymeric A stretches

    Science.gov (United States)

    Koutmou, Kristin S; Schuller, Anthony P; Brunelle, Julie L; Radhakrishnan, Aditya; Djuranovic, Sergej; Green, Rachel

    2015-01-01

    Protein output from synonymous codons is thought to be equivalent if appropriate tRNAs are sufficiently abundant. Here we show that mRNAs encoding iterated lysine codons, AAA or AAG, differentially impact protein synthesis: insertion of iterated AAA codons into an ORF diminishes protein expression more than insertion of synonymous AAG codons. Kinetic studies in E. coli reveal that differential protein production results from pausing on consecutive AAA-lysines followed by ribosome sliding on homopolymeric A sequence. Translation in a cell-free expression system demonstrates that diminished output from AAA-codon-containing reporters results from premature translation termination on out of frame stop codons following ribosome sliding. In eukaryotes, these premature termination events target the mRNAs for Nonsense-Mediated-Decay (NMD). The finding that ribosomes slide on homopolymeric A sequences explains bioinformatic analyses indicating that consecutive AAA codons are under-represented in gene-coding sequences. Ribosome ‘sliding’ represents an unexpected type of ribosome movement possible during translation. DOI: http://dx.doi.org/10.7554/eLife.05534.001 PMID:25695637

  2. Design of Chitosan and Its Water Soluble Derivatives-Based Drug Carriers with Polyelectrolyte Complexes

    OpenAIRE

    Wu, Qing-Xi; Lin, Dong-Qiang; Yao, Shan-Jing

    2014-01-01

    Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have...

  3. Use of a bacteriophage lysin to identify a novel target for antimicrobial development.

    Directory of Open Access Journals (Sweden)

    Raymond Schuch

    Full Text Available We identified an essential cell wall biosynthetic enzyme in Bacillus anthracis and an inhibitor thereof to which the organism did not spontaneously evolve measurable resistance. This work is based on the exquisite binding specificity of bacteriophage-encoded cell wall-hydrolytic lysins, which have evolved to recognize critical receptors within the bacterial cell wall. Focusing on the B. anthracis-specific PlyG lysin, we first identified its unique cell wall receptor and cognate biosynthetic pathway. Within this pathway, one biosynthetic enzyme, 2-epimerase, was required for both PlyG receptor expression and bacterial growth. The 2-epimerase was used to design a small-molecule inhibitor, epimerox. Epimerox prevented growth of several Gram-positive pathogens and rescued mice challenged with lethal doses of B. anthracis. Importantly, resistance to epimerox was not detected (<10(-11 frequency in B. anthracis and S. aureus. These results describe the use of phage lysins to identify promising lead molecules with reduced resistance potential for antimicrobial development.

  4. Genetic Analysis of Diaminopimelic Acid- and Lysine-Requiring Mutants of Escherichia coli1

    Science.gov (United States)

    Bukhari, Ahmad I.; Taylor, Austin L.

    1971-01-01

    Several diaminopimelic acid (DAP)- and lysine-requiring mutants of Escherichia coli were isolated and studied by genetic, physiological, and biochemical means. The genes concerned with DAP-lysine synthesis map at several different sites on the E. coli chromosome and, therefore, do not constitute a single operon. Three separate loci affecting DAP synthesis are located in the 0 to 2.5 min region of the genetic map. The order of the loci in this region is thr-dapB-pyrA-ara-leu-pan-dapC-tonA-dapD. Two additional DAP genes map in the region between min 47 and 48, with the gene order being gua-dapA-dapE-ctr. The lys locus at min 55 determines the synthesis of the enzyme DAP decarboxylase, which catalyzes the conversion of DAP into lysine. The order of the genes in this region is serA-lysA-thyA. PMID:4926684

  5. Predicting post-translational lysine acetylation using support vector machines

    DEFF Research Database (Denmark)

    Gnad, Florian; Ren, Shubin; Choudhary, Chunaram

    2010-01-01

    spectrometry to identify 3600 lysine acetylation sites on 1750 human proteins covering most of the previously annotated sites and providing the most comprehensive acetylome so far. This dataset should provide an excellent source to train support vector machines (SVMs) allowing the high accuracy in silico...

  6. CYLD, a deubiquitinase specific for lysine63-linked polyubiquitins, accumulates at the postsynaptic density in an activity-dependent manner

    International Nuclear Information System (INIS)

    Dosemeci, Ayse; Thein, Soe; Yang, Yijung; Reese, Thomas S.; Tao-Cheng, Jung-Hwa

    2013-01-01

    Highlights: ► CYLD is a deubiquitinase specific for lysine63-linked polyubiquitins. ► Presence of CYLD in PSDs is established by biochemistry and immunoEM. ► CYLD accumulates on PSDs upon depolarization of neurons. ► Accumulation of CYLD at PSDs may regulate trafficking/degradation of synaptic proteins. -- Abstract: Polyubiquitin chains on proteins flag them for distinct fates depending on the type of polyubiquitin linkage. While lysine48-linked polyubiquitination directs proteins to proteasomal degradation, lysine63-linked polyubiquitination promotes different protein trafficking and is involved in autophagy. Here we show that postsynaptic density (PSD) fractions from adult rat brain contain deubiquitinase activity that targets both lysine48 and lysine63-linked polyubiquitins. Comparison of PSD fractions with parent subcellular fractions by Western immunoblotting reveals that CYLD, a deubiquitinase specific for lysine63-linked polyubiquitins, is highly enriched in the PSD fraction. Electron microscopic examination of hippocampal neurons in culture under basal conditions shows immunogold label for CYLD at the PSD complex in approximately one in four synapses. Following depolarization by exposure to high K+, the proportion of CYLD-labeled PSDs as well as the labeling intensity of CYLD at the PSD increased by more than eighty percent, indicating that neuronal activity promotes accumulation of CYLD at the PSD. An increase in postsynaptic CYLD following activity would promote removal of lysine63-polyubiquitins from PSD proteins and thus could regulate their trafficking and prevent their autophagic degradation.

  7. Structure-activity studies of Wnt/β-catenin inhibition in the Niclosamide chemotype: Identification of derivatives with improved drug exposure.

    Science.gov (United States)

    Mook, Robert A; Wang, Jiangbo; Ren, Xiu-Rong; Chen, Minyong; Spasojevic, Ivan; Barak, Larry S; Lyerly, H Kim; Chen, Wei

    2015-09-01

    The Wnt signaling pathway plays a key role in regulation of organ development and tissue homeostasis. Dysregulated Wnt activity is one of the major underlying mechanisms responsible for many diseases including cancer. We previously reported the FDA-approved anthelmintic drug Niclosamide inhibits Wnt/β-catenin signaling and suppresses colon cancer cell growth in vitro and in vivo. Niclosamide is a multi-functional drug that possesses important biological activity in addition to inhibition of Wnt/β-catenin signaling. Here, we studied the SAR of Wnt signaling inhibition in the anilide and salicylamide region of Niclosamide. We found that the 4'-nitro substituent can be effectively replaced by trifluoromethyl or chlorine and that the potency of inhibition was dependent on the substitution pattern in the anilide ring. Non-anilide, N-methyl amides and reverse amide derivatives lost significant potency, while acylated salicylamide derivatives inhibited signaling with potency similar to non-acyl derivatives. Niclosamide's low systemic exposure when dosed orally may hinder its use to treat systemic disease. To overcome this limitation we identified an acyl derivative of Niclosamide, DK-520 (compound 32), that significantly increased both the plasma concentration and the duration of exposure of Niclosamide when dosed orally. The studies herein provide a medicinal chemical foundation to improve the pharmacokinetic exposure of Niclosamide and Wnt-signaling inhibitors based on the Niclosamide chemotype. The identification of novel derivatives of Niclosamide that metabolize to Niclosamide and increase its drug exposure may provide important research tools for in vivo studies and provide drug candidates for treating cancers with dysregulated Wnt signaling including drug-resistant cancers. Moreover, since Niclosamide is a multi-functional drug, new research tools such as DK520 could directly result in novel treatments against bacterial and viral infection, lupus, and metabolic

  8. Structure–activity studies of Wnt/β-catenin inhibition in the Niclosamide chemotype: Identification of derivatives with improved drug exposure

    Science.gov (United States)

    Mook, Robert A.; Wang, Jiangbo; Ren, Xiu-Rong; Chen, Minyong; Spasojevic, Ivan; Barak, Larry S.; Lyerly, H. Kim; Chen, Wei

    2015-01-01

    The Wnt signaling pathway plays a key role in regulation of organ development and tissue homeostasis. Dysregulated Wnt activity is one of the major underlying mechanisms responsible for many diseases including cancer. We previously reported the FDA-approved anthelmintic drug Niclosamide inhibits Wnt/β-catenin signaling and suppresses colon cancer cell growth in vitro and in vivo. Niclosamide is a multi-functional drug that possesses important biological activity in addition to inhibition of Wnt/β-catenin signaling. Here, we studied the SAR of Wnt signaling inhibition in the anilide and salicylamide region of Niclosamide. We found that the 4′-nitro substituent can be effectively replaced by trifluoromethyl or chlorine and that the potency of inhibition was dependent on the substitution pattern in the anilide ring. Non-anilide, N-methyl amides and reverse amide derivatives lost significant potency, while acylated salicylamide derivatives inhibited signaling with potency similar to non-acyl derivatives. Niclosamide's low systemic exposure when dosed orally may hinder its use to treat systemic disease. To overcome this limitation we identified an acyl derivative of Niclosamide, DK-520 (compound 32), that significantly increased both the plasma concentration and the duration of exposure of Niclosamide when dosed orally. The studies herein provide a medicinal chemical foundation to improve the pharmacokinetic exposure of Niclosamide and Wnt-signaling inhibitors based on the Niclosamide chemotype. The identification of novel derivatives of Niclosamide that metabolize to Niclosamide and increase its drug exposure may provide important research tools for in vivo studies and provide drug candidates for treating cancers with dysregulated Wnt signaling including drug-resistant cancers. Moreover, since Niclosamide is a multifunctional drug, new research tools such as DK520 could directly result in novel treatments against bacterial and viral infection, lupus, and metabolic

  9. The course of protein synthesis during grain filling in normal and high lysine barley

    International Nuclear Information System (INIS)

    Giese, H.; Andersen, B.

    1984-01-01

    A study of the course of protein synthesis during grain filling in Bomi and the high lysine barleys Hily 82/3 and Risoe 56 showed that the four salt-soluble proteins, protein Z, β-amylase and the chymotrypsin inhibitors CI-1 and CI-2, are synthesized in greater amounts earlier in the high lysine lines than in Bomi. On the other hand, the hordeins are synthesized in greater amounts earlier during grain filling in Bomi than in Hily 82/3 and Risoe 56. There is no indication of a significant reduction of total protein synthesis in the high lysine lines compared with the standard lines Bomi and Pirrka. Hily 82/3 and Risoe 56 are very similar in protein composition in that they have a lower hordein content and higher levels, particularly of β-amylase and the chymotrypsin inhibitors, than Bomi. (author)

  10. Glycated Lysine Residues: A Marker for Non-Enzymatic Protein Glycation in Age-Related Diseases

    OpenAIRE

    Ansari, Nadeem A.; Moinuddin,; Ali, Rashid

    2011-01-01

    Nonenzymatic glycosylation or glycation of macromolecules, especially proteins leading to their oxidation, play an important role in diseases. Glycation of proteins primarily results in the formation of an early stage and stable Amadori-lysine product which undergo further irreversible chemical reactions to form advanced glycation endproducts (AGEs). This review focuses these products in lysine rich proteins such as collagen and human serum albumin for their role in aging and age-related dise...

  11. Non-enzymatic N-acetylation of Lysine Residues by AcetylCoA Often Occurs via a Proximal S-acetylated Thiol Intermediate Sensitive to Glyoxalase II

    Directory of Open Access Journals (Sweden)

    Andrew M. James

    2017-02-01

    Full Text Available Summary: Acetyl coenzyme A (AcCoA, a key intermediate in mitochondrial metabolism, N-acetylates lysine residues, disrupting and, in some cases, regulating protein function. The mitochondrial lysine deacetylase Sirtuin 3 (Sirt3 reverses this modification with benefits reported in diabetes, obesity, and aging. We show that non-enzymatic lysine N-acetylation by AcCoA is greatly enhanced by initial acetylation of a cysteine residue, followed by SN-transfer of the acetyl moiety to a nearby lysine on mitochondrial proteins and synthetic peptides. The frequent occurrence of an S-acetyl intermediate before lysine N-acetylation suggests that proximity to a thioester is a key determinant of lysine susceptibility to acetylation. The thioesterase glyoxalase II (Glo2 can limit protein S-acetylation, thereby preventing subsequent lysine N-acetylation. This suggests that the hitherto obscure role of Glo2 in mitochondria is to act upstream of Sirt3 in minimizing protein N-acetylation, thus limiting protein dysfunction when AcCoA accumulates. : James et al. show that the non-enzymatic N-acetylation of lysine residues in mitochondrial proteins frequently occurs via a proximal S-acetylated thiol intermediate. Glutathione equilibrates with this intermediate, allowing the thioesterase glyoxalase II to limit protein lysine N-acetylation. These findings expand our understanding of how protein acetylation arises. Keywords: AcetylCoA, lysine acetylation, glyoxalase

  12. Herb-drug interaction prediction based on the high specific inhibition of andrographolide derivatives towards UDP-glucuronosyltransferase (UGT) 2B7.

    Science.gov (United States)

    Ma, Hai-Ying; Sun, Dong-Xue; Cao, Yun-Feng; Ai, Chun-Zhi; Qu, Yan-Qing; Hu, Cui-Min; Jiang, Changtao; Dong, Pei-Pei; Sun, Xiao-Yu; Hong, Mo; Tanaka, Naoki; Gonzalez, Frank J; Ma, Xiao-Chi; Fang, Zhong-Ze

    2014-05-15

    Herb-drug interaction strongly limits the clinical application of herbs and drugs, and the inhibition of herbal components towards important drug-metabolizing enzymes (DMEs) has been regarded as one of the most important reasons. The present study aims to investigate the inhibition potential of andrographolide derivatives towards one of the most important phase II DMEs UDP-glucuronosyltransferases (UGTs). Recombinant UGT isoforms (except UGT1A4)-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction and UGT1A4-catalyzed trifluoperazine (TFP) glucuronidation were employed to firstly screen the andrographolide derivatives' inhibition potential. High specific inhibition of andrographolide derivatives towards UGT2B7 was observed. The inhibition type and parameters (Ki) were determined for the compounds exhibiting strong inhibition capability towards UGT2B7, and human liver microsome (HLMs)-catalyzed zidovudine (AZT) glucuronidation probe reaction was used to furtherly confirm the inhibition behavior. In combination of inhibition parameters (Ki) and in vivo concentration of andrographolide and dehydroandrographolide, the potential in vivo inhibition magnitude was predicted. Additionally, both the in vitro inhibition data and computational modeling results provide important information for the modification of andrographolide derivatives as selective inhibitors of UGT2B7. Taken together, data obtained from the present study indicated the potential herb-drug interaction between Andrographis paniculata and the drugs mainly undergoing UGT2B7-catalyzed metabolic elimination, and the andrographolide derivatives as potential candidates for the selective inhibitors of UGT2B7. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Metabolic responses to pyruvate kinase deletion in lysine producing Corynebacterium glutamicum

    Directory of Open Access Journals (Sweden)

    Wittmann Christoph

    2008-03-01

    Full Text Available Abstract Background Pyruvate kinase is an important element in flux control of the intermediate metabolism. It catalyzes the irreversible conversion of phosphoenolpyruvate into pyruvate and is under allosteric control. In Corynebacterium glutamicum, this enzyme was regarded as promising target for improved production of lysine, one of the major amino acids in animal nutrition. In pyruvate kinase deficient strains the required equimolar ratio of the two lysine precursors oxaloacetate and pyruvate can be achieved through concerted action of the phosphotransferase system (PTS and phosphoenolpyruvate carboxylase (PEPC, whereby a reduced amount of carbon may be lost as CO2 due to reduced flux into the tricarboxylic acid (TCA cycle. In previous studies, deletion of pyruvate kinase in lysine-producing C. glutamicum, however, did not yield a clear picture and the exact metabolic consequences are not fully understood. Results In this work, deletion of the pyk gene, encoding pyruvate kinase, was carried out in the lysine-producing strain C. glutamicum lysCfbr, expressing a feedback resistant aspartokinase, to investigate the cellular response to deletion of this central glycolytic enzyme. Pyk deletion was achieved by allelic replacement, verified by PCR analysis and the lack of in vitro enzyme activity. The deletion mutant showed an overall growth behavior (specific growth rate, glucose uptake rate, biomass yield which was very similar to that of the parent strain, but differed in slightly reduced lysine formation, increased formation of the overflow metabolites dihydroxyacetone and glycerol and in metabolic fluxes around the pyruvate node. The latter involved a flux shift from pyruvate carboxylase (PC to PEPC, by which the cell maintained anaplerotic supply of the TCA cycle. This created a metabolic by-pass from PEP to pyruvate via malic enzyme demonstrating its contribution to metabolic flexibility of C. glutamicum on glucose. Conclusion The metabolic

  14. Ex-vivo absorption study of lysine R-lipoate salt, a new pharmaceutical form of R-ALA.

    Science.gov (United States)

    Amenta, Francesco; Buccioni, Michela; Ben, Diego Dal; Lambertucci, Catia; Navia, Aleix Martí; Ngouadjeu Ngnintedem, Michael A; Ricciutelli, Massimo; Spinaci, Andrea; Volpini, Rosaria; Marucci, Gabriella

    2018-06-15

    Alpha-lipoic acid (ALA) oral supplements were used in many pathologies associated with increased oxidative stress. Although only R-ALA is considered the biologically active form, R,S-ALA is used in therapeutic applications even showing poor water solubility. The aim of this work was to study the absorption and transport mechanism across the intestinal barrier of new R-ALA stable and water soluble form, consisting in the lysine R-ALA salt, in presence and absence of specific inhibitors of Na + /multivitamin (SMVT) and monocarboxylic acids (MCT). The absorption of a new ALA form was investigated at rat everted sacs in comparison with R-ALA, S-ALA, and R,S-ALA. Results showed that duodenum is the best portion of intestine for ALA forms absorption. The absorption percentage of R-ALA, S-ALA, R,S-ALA, and lysine R-ALA salt was 66%, 43%, 55%, and 70%, respectively. The modest effect of the SMVT inhibitor biotin demonstrated that this transporter system is not principally involved in the absorption of lysine R-lipoate salt across the rat intestinal barrier. On the contrary, the MCT inhibitor octanoic acid significantly reduced the transport of this salt, whit an absorption decrease of R-ALA and lysine R-lipoate salt of 28% and 24%, respectively. Since the highest concentration of these inhibitors did not completely inhibit the absorption of lysine R-lipoate salt, other transport mechanisms probably operate for its intracellular delivery. The new form of ALA, lysine R-lipoate salt, was the most absorbed respect to the other ALA forms demonstrating that this compound is more suitable for oral administration. This new salt could represent a promising candidate for ALA oral supplementation. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. CYLD, a deubiquitinase specific for lysine63-linked polyubiquitins, accumulates at the postsynaptic density in an activity-dependent manner

    Energy Technology Data Exchange (ETDEWEB)

    Dosemeci, Ayse, E-mail: dosemeca@mail.nih.gov [Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892 (United States); Thein, Soe; Yang, Yijung; Reese, Thomas S. [Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892 (United States); Tao-Cheng, Jung-Hwa [EM Facility, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892 (United States)

    2013-01-04

    Highlights: Black-Right-Pointing-Pointer CYLD is a deubiquitinase specific for lysine63-linked polyubiquitins. Black-Right-Pointing-Pointer Presence of CYLD in PSDs is established by biochemistry and immunoEM. Black-Right-Pointing-Pointer CYLD accumulates on PSDs upon depolarization of neurons. Black-Right-Pointing-Pointer Accumulation of CYLD at PSDs may regulate trafficking/degradation of synaptic proteins. -- Abstract: Polyubiquitin chains on proteins flag them for distinct fates depending on the type of polyubiquitin linkage. While lysine48-linked polyubiquitination directs proteins to proteasomal degradation, lysine63-linked polyubiquitination promotes different protein trafficking and is involved in autophagy. Here we show that postsynaptic density (PSD) fractions from adult rat brain contain deubiquitinase activity that targets both lysine48 and lysine63-linked polyubiquitins. Comparison of PSD fractions with parent subcellular fractions by Western immunoblotting reveals that CYLD, a deubiquitinase specific for lysine63-linked polyubiquitins, is highly enriched in the PSD fraction. Electron microscopic examination of hippocampal neurons in culture under basal conditions shows immunogold label for CYLD at the PSD complex in approximately one in four synapses. Following depolarization by exposure to high K+, the proportion of CYLD-labeled PSDs as well as the labeling intensity of CYLD at the PSD increased by more than eighty percent, indicating that neuronal activity promotes accumulation of CYLD at the PSD. An increase in postsynaptic CYLD following activity would promote removal of lysine63-polyubiquitins from PSD proteins and thus could regulate their trafficking and prevent their autophagic degradation.

  16. Efficacy and tolerance of lysine clonixinate versus paracetamol/codeine following inguinal hernioplasty.

    Science.gov (United States)

    de los Santos, A R; Di Girolamo, G; Martí, M L

    1998-01-01

    In this study lysine clonixinate, a nonsteroidal antiinflammatory agent with selective inhibition of cyclooxygenase-2 and 5-lipooxygenase in in vitro and in vivo pharmacodynamic studies, was evaluated in a prospective, randomized, double-blind, double-dummy clinical study versus paracetamol/codeine, in 151 patients with pain following inguinal hernioplasty. Patients were treated with one 125 mg tablet of lysine clonixinate or paracetamol/codeine (500 mg + 30 mg) administered at fixed doses every 4 h during 2 days. Controls were carried out 1, 2 and 4 h after the first intake of day 1 and day 2. Each control included assessment of pain at rest, when coughing, sitting and upon moderate pressure. Both treatment groups (lysine clonixinate, 77 patients and paracetamol/codeine, 74 patients) were comparable in terms of demographic and baseline pain intensities. Spontaneous pain was reduced significantly in both treatment groups from the 1st-h control. The following values were recorded in the lysine clonixinate group during day 1: baseline: 6.86 +/- 1.24; 1st h: 4.49 +/- 1.77; 2nd h: 2.96 +/- 1.74; 4th h: 2.23 +/- 1.51. The following values for the same group during day 2 were: predose: 1.70 +/- 1.64; 1st h: 1.16 +/- 1.17; 2nd h: 0.78 +/- 1.06; 4th h: 0.63 +/- 1.05. The paracetamol/codeine group revealed the following values: day 1: baseline: 6.72 +/- 1.22; 1st h: 4.57 +/- 1.72; 2nd h: 2.97 +/- 1.68; 4th h: 2.47 +/- 1.68 and day 2: predose: 2.02 +/- 1.57; 1st h: 1.32 +/- 1.23; 2nd h: 0.82 +/- 0.99; 4th h: 0.66 +/- 0.89. Reduction of pain induced by coughing, sitting and pressure showed similar behavior patterns. No significant differences between both treatment groups were encountered in terms of analgesic efficacy. Incidence of adverse effects was significantly higher in the paracetamol/codeine group (X2: p lysine clonixinate group four out of 77 patients showed side effects but these did not require treatment discontinuation.

  17. Effect of Low Protein-Methionine-and-Lysine-Supplemented Diets ...

    African Journals Online (AJOL)

    Two experiments were conducted to investigate the effect of supplementing low CP diets with methionine and lysine on broiler performance, carcass measure and their immune response against Infectious Bursa Disease (IBD) virus. In Experiment 1, ten diets were formulated. Diet 1 (control diet) contained 23.0% CP and ...

  18. DNA Damage-Induced Acetylation of Lysine 3016 of ATM Activates ATM Kinase Activity▿ †

    OpenAIRE

    Sun, Yingli; Xu, Ye; Roy, Kanaklata; Price, Brendan D.

    2007-01-01

    The ATM protein kinase is essential for cells to repair and survive genotoxic events. The activation of ATM's kinase activity involves acetylation of ATM by the Tip60 histone acetyltransferase. In this study, systematic mutagenesis of lysine residues was used to identify regulatory ATM acetylation sites. The results identify a single acetylation site at lysine 3016, which is located in the highly conserved C-terminal FATC domain adjacent to the kinase domain. Antibodies specific for acetyl-ly...

  19. Effect of irradiation on Nε-carboxymethyl-lysine and Nε-carboxyethyl-lysine formation in cooked meat products during storage

    International Nuclear Information System (INIS)

    Yu, Ligang; He, Zhiyong; Zeng, Maomao; Zheng, Zongping; Chen, Jie

    2016-01-01

    This study investigated the effects of irradiation on N ε -carboxymethyl-lysine (CML) and N ε -carboxyethyl-lysine (CEL) formation in cooked red and white meats during storage. The results showed that irradiation did not affect CML/CEL formation (0 weeks). After 6 weeks, CML/CEL contents in the irradiated samples exhibited a higher growth rate than the non-irradiated samples, especially the red meat. The results of electron spin resonance spectrometry and 2-Thiobarbituric acid-reactive substances suggested irradiation had induced free-radical reactions and accelerated lipid oxidation during storage. A linear correlation (r=0.810–0.906, p<0.01) was found between the loss of polyunsaturated fatty acids content and increase of CML/CEL content in the irradiated samples after 0 and 6 weeks of storage. The results indicate that irradiation-induced lipid oxidation promotes CML/CEL formation, and CML/CEL formation by the lipid oxidation pathways may be an important pathway for CML/CEL accumulation in irradiated meat products during storage. - Highlights: • The effect of irradiation on CML and CEL formation in meat products is investigated. • CML and CEL contents in irradiated meat products exhibit a higher growth rate than non-irradiated samples. • PUFAs oxidation induced by irradiation promotes CML and CEL formation. • Lipid oxidation pathways are an important pathway for CML and CEL accumulation in irradiated samples during storage.

  20. Proteome-wide mapping of the Drosophila acetylome demonstrates a high degree of conservation of lysine acetylation

    DEFF Research Database (Denmark)

    Weinert, Brian T; Wagner, Sebastian A; Horn, Heiko

    2011-01-01

    Posttranslational modification of proteins by acetylation and phosphorylation regulates most cellular processes in living organisms. Surprisingly, the evolutionary conservation of phosphorylated serine and threonine residues is only marginally higher than that of unmodified serines and threonines....... With high-resolution mass spectrometry, we identified 1981 lysine acetylation sites in the proteome of Drosophila melanogaster. We used data sets of experimentally identified acetylation and phosphorylation sites in Drosophila and humans to analyze the evolutionary conservation of these modification sites...... between flies and humans. Site-level conservation analysis revealed that acetylation sites are highly conserved, significantly more so than phosphorylation sites. Furthermore, comparison of lysine conservation in Drosophila and humans with that in nematodes and zebrafish revealed that acetylated lysines...

  1. Comparative Analysis of Proteome-Wide Lysine Acetylation in Juvenile and Adult Schistosoma japonicum

    Directory of Open Access Journals (Sweden)

    Qing Li

    2017-11-01

    Full Text Available Schistosomiasis is a devastating parasitic disease caused by tremotodes of the genus Schistosoma. Eggs produced by sexually mature schistosomes are the causative agents of for pathogenesis and transmission. Elucidating the molecular mechanism of schistosome development and sexual maturation would facilitate the prevention and control of schistosomiasis. Acetylation of lysine is a dynamic and reversible post-translational modification playing keys role in many biological processes including development in both eukaryotes and prokaryotes. To investigate the impacts of lysine acetylation on Schistosoma japonicum (S. japonicum development and sexual maturation, we used immunoaffinity-based acetyllysine peptide enrichment combined with mass spectrometry (MS, to perform the first comparative analysis of proteome-wide lysine acetylation in both female and male, juvenile (18 days post infection, 18 dpi and adult (28 dpi schistosome samples. In total, we identified 874 unique acetylated sites in 494 acetylated proteins. The four samples shared 47 acetylated sites and 46 proteins. More acetylated sites and proteins shared by both females and males were identified in 28 dpi adults (189 and 143, respectively than in 18 dpi schistosomula (76 and 59, respectively. More stage-unique acetylated sites and proteins were also identified in 28 dpi adults (494 and 210, respectively than in 18 dpi schistosomula (73 and 44, respectively. Functional annotation showed that in different developmental stages and genders, a number of proteins involving in muscle movement, glycometabolism, lipid metabolism, energy metabolism, environmental stress resistance, antioxidation, etc., displayed distinct acetylation profiles, which was in accordance with the changes of their biological functions during schistosome development, suggesting that lysine acetylation modification exerted important regulatory roles in schistosome development. Taken together, our data provided the first

  2. Bioinspired Cell-Derived Nanovesicles versus Exosomes as Drug Delivery Systems : A Cost-Effective Alternative

    NARCIS (Netherlands)

    Goh, Wei Jiang; Zou, Shui; Ong, Wei Yi; Torta, Federico; Alexandra, Alvarez Fernandez; Schiffelers, Raymond M.; Storm, Gert; Wang, Jiong-Wei; Czarny, Bertrand M S; Pastorin, Giorgia

    2017-01-01

    Cell Derived Nanovesicles (CDNs) have been developed from the rapidly expanding field of exosomes, representing a class of bioinspired Drug Delivery Systems (DDS). However, translation to clinical applications is limited by the low yield and multi-step approach in isolating naturally secreted

  3. Bioinspired Cell-Derived Nanovesicles versus Exosomes as Drug Delivery Systems : a Cost-Effective Alternative

    NARCIS (Netherlands)

    Goh, Wei Jiang; Zou, Shui; Ong, Wei Yi; Torta, Federico; Alexandra, Alvarez Fernandez; Schiffelers, Raymond M; Storm, G; Wang, Jiong Wei; Czarny, Bertrand; Pastorin, Giorgia

    2017-01-01

    Cell Derived Nanovesicles (CDNs) have been developed from the rapidly expanding field of exosomes, representing a class of bioinspired Drug Delivery Systems (DDS). However, translation to clinical applications is limited by the low yield and multi-step approach in isolating naturally secreted

  4. Rational modification of Corynebacterium glutamicum dihydrodipicolinate reductase to switch the nucleotide-cofactor specificity for increasing l-lysine production.

    Science.gov (United States)

    Xu, Jian-Zhong; Yang, Han-Kun; Liu, Li-Ming; Wang, Ying-Yu; Zhang, Wei-Guo

    2018-03-25

    l-lysine is an important amino acid in animals and humans and NADPH is a vital cofactor for maximizing the efficiency of l-lysine fermentation. Dihydrodipicolinate reductase (DHDPR), an NAD(P)H-dependent enzyme, shows a variance in nucleotide-cofactor affinity in bacteria. In this study, we rationally engineered Corynebacterium glutamicum DHDPR (CgDHDPR) to switch its nucleotide-cofactor specificity resulting in an increase in final titer (from 82.6 to 117.3 g L -1 ), carbon yield (from 0.35 to 0.44 g [g glucose] -1 ) and productivity (from 2.07 to 2.93 g L -1  hr -1 ) of l-lysine in JL-6 ΔdapB::Ec-dapB C115G,G116C in fed-batch fermentation. To do this, we comparatively analyzed the characteristics of CgDHDPR and Escherichia coli DHDPR (EcDHDPR), indicating that hetero-expression of NADH-dependent EcDHDPR increased l-lysine production. Subsequently, we rationally modified the conserved structure of cofactor-binding motif, and results indicated that introducing the mutation K11A or R13A in CgDHDPR and introducing the mutation R16A or R39A in EcDHDPR modifies the nucleotide-cofactor affinity of DHDPR. Lastly, the effects of these mutated DHDPRs on l-lysine production were investigated. The highest increase (26.2%) in l-lysine production was observed for JL-6 ΔdapB::Ec-dapB C115G,G116C , followed by JL-6 Cg-dapB C37G,G38C (21.4%) and JL-6 ΔdapB::Ec-dapB C46G,G47C (15.2%). This is the first report of a rational modification of DHDPR that enhances the l-lysine production and yield through the modulation of nucleotide-cofactor specificity. © 2018 Wiley Periodicals, Inc.

  5. Effect of amino acids lysine and arginine on fracture healing in rabbits: A radiological and histomorphological analysis

    Directory of Open Access Journals (Sweden)

    Sinha Shivam

    2009-01-01

    Full Text Available Background: Amino acids like arginine and lysine have been suggested to hasten the process of fracture healing by improving the local blood supply, supplementing growth factors, and improving collagen synthesis. We studied the role of lysine and arginine in the fracture repair process with regard to the rate of healing, probable mechanisms involved in the process, and mutual synergism between these agents. Materials and Methods: In an experimental study, 40 rabbits were subjected to ulnar osteotomy. They were distributed in control (14 and test groups (26. Twenty-six animals in the test group were fed with a diet rich in lysine and arginine. Both the groups were followed radiologically and histologically till union. Results: There was better healing of osteotomy in terms of better vascularization, callus formation, and mineralization in the test group. The time of healing in the test group was reduced by a period of 2 weeks. Conclusion: We conclude that amino acids like arginine and lysine may hasten fracture healing.

  6. Digestible threonine to lysine ratio in diets for laying hens aged 24-40 weeks

    Directory of Open Access Journals (Sweden)

    Tatiana Cristina da Rocha

    2013-12-01

    Full Text Available Two-hundred sixteen white laying hens were used to assess the ideal ratio of digestible threonine:lysine in diets for laying hens at 24 to 40 weeks of age. Birds were assigned to a randomized block design, with six treatments, six replicates per treatment and six birds per experimental unit. The cage was used as the blocking criterion. Experimental diets contained different digestible threonine:digestible lysine ratios (65, 70, 75, 80, 85 and 90% with 142 g/kg of crude protein. Experimental diets were formulated to be isonitrogenous and isocaloric with different contents of L-glutamic acid. Feed intake (g/hen/d, egg production (%, egg weight (g, egg mass (g/hen/d, feed conversion ratio (kg/dozen and kg/kg egg, eggshell weight (g, albumen weight (g, yolk weight (g and body weight gain (g were assessed. The maximum egg production was observed at 78% digestible threonine:digestible lysine ratio, while the best values of feed conversion ratio (kg/dozen egg and feed conversion ratio (kg/kg of egg were observed at 77.6% and 75%, respectively. Feed intake, egg mass and egg contents (yolk, albumen and eggshell were not affected by treatments. The estimated digestible threonine:digestible lysine ratio of Hy-Line W36 laying hens at 24 to 40 weeks of age is 78%, corresponding to 5.70 g/kg of dietary digestible threonine.

  7. Aflatoxin exposure during the first 1000 days of life in rural South Asia assessed by aflatoxin B₁-lysine albumin biomarkers.

    Science.gov (United States)

    Groopman, John D; Egner, Patricia A; Schulze, Kerry J; Wu, Lee S-F; Merrill, Rebecca; Mehra, Sucheta; Shamim, Abu A; Ali, Hasmot; Shaikh, Saijuddin; Gernand, Alison; Khatry, Subarna K; LeClerq, Steven C; West, Keith P; Christian, Parul

    2014-12-01

    Aflatoxin B1 is a potent carcinogen, occurring from mold growth that contaminates staple grains in hot, humid environments. In this investigation, aflatoxin B1-lysine albumin biomarkers were measured by mass spectrometry in rural South Asian women, during the first and third trimester of pregnancy, and their children at birth and at two years of age. These subjects participated in randomized community trials of antenatal micronutrient supplementation in Sarlahi District, southern Nepal and Gaibandha District in northwestern Bangladesh. Findings from the Nepal samples demonstrated exposure to aflatoxin, with 94% detectable samples ranging from 0.45 to 2939.30 pg aflatoxin B1-lysine/mg albumin during pregnancy. In the Bangladesh samples the range was 1.56 to 63.22 pg aflatoxin B1-lysine/mg albumin in the first trimester, 3.37 to 72.8 pg aflatoxin B1-lysine/mg albumin in the third trimester, 4.62 to 76.69 pg aflatoxin B1-lysine/mg albumin at birth and 3.88 to 81.44 pg aflatoxin B1-lysine/mg albumin at age two years. Aflatoxin B1-lysine adducts in cord blood samples demonstrated that the fetus had the capacity to convert aflatoxin into toxicologically active compounds and the detection in the same 2-year-old children illustrates exposure over the first 1000 days of life. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Novel Therapeutic Strategies in the Management of Non-Variceal Upper Gastrointestinal Bleeding

    Directory of Open Access Journals (Sweden)

    Ari Garber

    2016-09-01

    Full Text Available Non-variceal upper gastrointestinal bleeding, the most common etiology of which is peptic ulcer disease, remains a persistent challenge despite a reduction in both its incidence and mortality. Both pharmacologic and endoscopic techniques have been developed to achieve hemostasis, with varying degrees of success. Among the pharmacologic therapies, proton pump inhibitors remain the mainstay of treatment, as they reduce the risk of rebleeding and requirement for recurrent endoscopic evaluation. Tranexamic acid, a derivative of the amino acid lysine, is an antifibrinolytic agent whose role requires further investigation before application. Endoscopically delivered pharmacotherapy, including Hemospray (Cook Medical, EndoClot (EndoClot Plus Inc., and Ankaferd Blood Stopper (Ankaferd Health Products, in addition to standard epinephrine, show promise in this regard, although their mechanisms of action require further investigation. Non-pharmacologic endoscopic techniques use one of the following two methods to achieve hemostasis: ablation or mechanical tamponade, which may involve using endoscopic clips, cautery, argon plasma coagulation, over-the-scope clipping devices, radiofrequency ablation, and cryotherapy. This review aimed to highlight these novel and fundamental hemostatic strategies and the research supporting their efficacy.

  9. DFT application for chlorin derivatives photosensitizer drugs modeling

    Science.gov (United States)

    Machado, Neila; Carvalho, B. G.; Téllez Soto, C. A.; Martin, A. A.; Favero, P. P.

    2018-04-01

    Photodynamic therapy is an alternative form of cancer treatment that meets the desire for a less aggressive approach to the body. It is based on the interaction between a photosensitizer, activating light, and molecular oxygen. This interaction results in a cascade of reactions that leads to localized cell death. Many studies have been conducted to discover an ideal photosensitizer, which aggregates all the desirable characteristics of a potent cell killer and generates minimal side effects. Using Density Functional Theory (DFT) implemented in the program Vienna Ab-initio Simulation Package, new chlorin derivatives with different functional groups were simulated to evaluate the different absorption wavelengths to permit resonant absorption with the incident laser. Gaussian 09 program was used to determine vibrational wave numbers and Natural Bond Orbitals. The chosen drug with the best characteristics for the photosensitizer was a modified model of the original chlorin, which was called as Thiol chlorin. According to our calculations it is stable and is 19.6% more efficient at optical absorption in 708 nm in comparison to the conventional chlorin e6. Vibrational modes, optical and electronic properties were predicted. In conclusion, this study is an attempt to improve the development of new photosensitizer drugs through computational methods that save time and contribute to decrease the numbers of animals for model application.

  10. In silico modeling predicts drug sensitivity of patient-derived cancer cells.

    Science.gov (United States)

    Pingle, Sandeep C; Sultana, Zeba; Pastorino, Sandra; Jiang, Pengfei; Mukthavaram, Rajesh; Chao, Ying; Bharati, Ila Sri; Nomura, Natsuko; Makale, Milan; Abbasi, Taher; Kapoor, Shweta; Kumar, Ansu; Usmani, Shahabuddin; Agrawal, Ashish; Vali, Shireen; Kesari, Santosh

    2014-05-21

    Glioblastoma (GBM) is an aggressive disease associated with poor survival. It is essential to account for the complexity of GBM biology to improve diagnostic and therapeutic strategies. This complexity is best represented by the increasing amounts of profiling ("omics") data available due to advances in biotechnology. The challenge of integrating these vast genomic and proteomic data can be addressed by a comprehensive systems modeling approach. Here, we present an in silico model, where we simulate GBM tumor cells using genomic profiling data. We use this in silico tumor model to predict responses of cancer cells to targeted drugs. Initially, we probed the results from a recent hypothesis-independent, empirical study by Garnett and co-workers that analyzed the sensitivity of hundreds of profiled cancer cell lines to 130 different anticancer agents. We then used the tumor model to predict sensitivity of patient-derived GBM cell lines to different targeted therapeutic agents. Among the drug-mutation associations reported in the Garnett study, our in silico model accurately predicted ~85% of the associations. While testing the model in a prospective manner using simulations of patient-derived GBM cell lines, we compared our simulation predictions with experimental data using the same cells in vitro. This analysis yielded a ~75% agreement of in silico drug sensitivity with in vitro experimental findings. These results demonstrate a strong predictability of our simulation approach using the in silico tumor model presented here. Our ultimate goal is to use this model to stratify patients for clinical trials. By accurately predicting responses of cancer cells to targeted agents a priori, this in silico tumor model provides an innovative approach to personalizing therapy and promises to improve clinical management of cancer.

  11. Patient-derived stem cells: pathways to drug discovery for brain diseases

    Directory of Open Access Journals (Sweden)

    Alan eMackay-Sim

    2013-03-01

    Full Text Available The concept of drug discovery through stem cell biology is based on technological developments whose genesis is now coincident. The first is automated cell microscopy with concurrent advances in image acquisition and analysis, known as high content screening (HCS. The second is patient-derived stem cells for modelling the cell biology of brain diseases. HCS has developed from the requirements of the pharmaceutical industry for high throughput assays to screen thousands of chemical compounds in the search for new drugs. HCS combines new fluorescent probes with automated microscopy and computational power to quantify the effects of compounds on cell functions. Stem cell biology has advanced greatly since the discovery of genetic reprogramming of somatic cells into induced pluripotent stem cells (iPSCs. There is now a rush of papers describing their generation from patients with various diseases of the nervous system. Although the majority of these have been genetic diseases, iPSCs have been generated from patients with complex diseases (schizophrenia and sporadic Parkinson’s disease. Some genetic diseases are also modelled in embryonic stem cells generated from blastocysts rejected during in vitro fertilisation. Neural stem cells have been isolated from post-mortem brain of Alzheimer’s patients and neural stem cells generated from biopsies of the olfactory organ of patients is another approach. These olfactory neurosphere-derived cells demonstrate robust disease-specific phenotypes in patients with schizophrenia and Parkinson’s disease. High content screening is already in use to find small molecules for the generation and differentiation of embryonic stem cells and induced pluripotent stem cells. The challenges for using stem cells for drug discovery are to develop robust stem cell culture methods that meet the rigorous requirements for repeatable, consistent quantities of defined cell types at the industrial scale necessary for high

  12. Lysine demethylase inhibition protects pancreatic β cells from apoptosis and improves β-cell function

    DEFF Research Database (Denmark)

    Backe, Marie Balslev; Andersson, Jan Legaard; Bacos, Karl

    2018-01-01

    ) protects β cells from cytokine-induced apoptosis and reduces type 1 diabetes incidence in animals. We hypothesized that also lysine demethylases (KDMs) regulate β-cell fate in response to inflammatory stress. Expression of the demethylase Kdm6B was upregulated by proinflammatory cytokines suggesting......Transcriptional changes control β-cell survival in response to inflammatory stress. Posttranslational modifications of histone and non-histone transcriptional regulators activate or repress gene transcription, but the link to cell-fate signaling is unclear. Inhibition of lysine deacetylases (KDACs...

  13. Piezoelectric and pyroelectric properties of DL-alanine and L-lysine amino-acid polymer nanofibres

    Science.gov (United States)

    de Matos Gomes, Etelvina; Viseu, Teresa; Belsley, Michael; Almeida, Bernardo; Costa, Maria Margarida R.; Rodrigues, Vitor H.; Isakov, Dmitry

    2018-04-01

    The piezoelectric and pyroelectric properties of electrospun polyethylene oxide nanofibres embedded with polar amino acids DL-alanine and L-lysine hemihydrate are reported. A high pyroelectric coefficient of 150 μC m‑2 K‑1 was measured for L-lysine hemihydrate and piezoelectric current densities up to 7 μA m‑2 were obtained for the nanofibres. The study reveals a potential for polymer amino-acid nanofibres to be used as biocompatible energy harvesters for autonomous circuit applications like in implantable electronics.

  14. Chemical modification of lysine residues in lysozyme may dramatically influence its amyloid fibrillation.

    Science.gov (United States)

    Morshedi, Dina; Ebrahim-Habibi, Azadeh; Moosavi-Movahedi, Ali Akbar; Nemat-Gorgani, Mohsen

    2010-04-01

    Studies on the aggregation of mutant proteins have provided new insights into the genetics of amyloid diseases and the role of the net charge of the protein on the rate, extent, and type of aggregate formation. In the present work, hen egg white lysozyme (HEWL) was employed as the model protein. Acetylation and (separately) citraconylation were employed to neutralize the charge on lysine residues. Acetylation of the lysine residues promoted amyloid formation, resulting in more pronounced fibrils and a dramatic decline in the nucleation time. In contrast, citraconylation produced the opposite effect. In both cases, native secondary and tertiary structures appeared to be retained. Studies on the effect of pH on aggregation suggested greater possibilities for amorphous aggregate formation rather than fibrillation at pH values closer to neutrality, in which the protein is known to take up a conformation more similar to its native form. This is in accord with reports in the literature suggesting that formation of amorphous aggregates is more favored under relatively more native conditions. pH 5 provided a critical environment in which a mixture of amorphous and fibrillar structures were observed. Use of Tango and Aggrescan software which describe aggregation tendencies of different parts of a protein structure suggested critical importance of some of the lysine residues in the aggregation process. Results are discussed in terms of the importance of the net charge in control of protein-protein interactions leading to aggregate formation and possible specific roles of lysine residues 96 and 97. Copyright 2009 Elsevier B.V. All rights reserved.

  15. Effect of dietary nutrients on ileal endogenous losses of threonine, cysteine, methionine, lysine, leucine and protein in broiler chicks.

    Science.gov (United States)

    Cerrate, S; Vignale, S K; Ekmay, R; England, J; Coon, C

    2018-04-01

    An isotope dose technique was utilized (i) to determine endogenous amino acid (AA) and protein losses and (ii) to propose adjusted values for AA requirements. The endogenous flow rate was calculated from the pool of enrichment in plasma AA, assuming similitude to enrichment of endogenous AA. In experiment 1, chicks were orally administered D4-lysine at 2% of estimated lysine intake from 16 to 24 days to find the isotopic steady state of the atom percent excess (APE) of lysine for plasma and jejunal and ileal digesta. The APE of D4-lysine in plasma, jejunal digesta and ileal digesta reached the isotopic steady state at 5.5, 3.4 and 2.0 days, respectively, by using the broken-line model. It was assumed that the isotopic steady state at 5 days identified for D4-lysine is also representative for the 15N-labeled AA. In experiment 2, chicks were fed diets from 1 to 21 days with increasing levels of fat (6%, 8%, 12%, 13% extract ether), protein (26%, 28.5%, 31% CP) or fiber (14%, 16%, 18% NDF) by adding poultry fat, soybean meal, blended animal protein or barley. Chicks were orally administered 15N-threonine, 15N-cysteine, 15N-methionine, 15N-lysine and 15N-leucine at 2% of estimated daily intake for 5 days from 17 to 21 days of age. Dietary nutrients influenced endogenous losses (EL), where dietary fat stimulated EL of lysine (P=0.06), leucine and protein (P=0.07); dietary protein enhanced EL of leucine and protein; and finally the dietary fiber increased EL of leucine. Dietary nutrients also affected apparent ileal digestibility (AID). Dietary fat increased AID of cysteine but decreased AID of lysine. Dietary protein reduced AID of protein, threonine, lysine and leucine, and similarly dietary fiber decreased AID of protein, threonine, methionine, lysine and leucine. In contrast, dietary fat or protein did not affect real ileal digestibility (RID) of protein and AA except threonine and leucine. The dietary fiber reduced the RID of protein, threonine and leucine. This

  16. Enantioselective adsorption of ibuprofen and lysine in metal-organic frameworks

    NARCIS (Netherlands)

    Bueno-Perez, R.; Martin-Calvo, A.; Gómez-Álvarez, P.; Gutiérrez-Sevillano, J.J.; Merkling, P.J.; Vlugt, T.J.H.; van Erp, T.S.; Dubbeldam, D.; Calero, S.

    2014-01-01

    This study reveals the efficient enantiomeric separation of bioactive molecules in the liquid phase. Chiral structure HMOF-1 separates racemic mixtures whereas heteroselectivity is observed for scalemic mixtures of ibuprofen using non-chiral MIL-47 and MIL-53. Lysine enantiomers are only separated

  17. Amino acid nutrition beyond methionine and lysine for milk protein

    Science.gov (United States)

    Amino acids are involved in many important physiological processes affecting the production, health, and reproduction of high-producing dairy cows. Most research and recommendations for lactating dairy cows has focused on methionine and lysine for increasing milk protein yield. This is because these...

  18. Development of surface-engineered PLGA nanoparticulate-delivery system of Tet1-conjugated nattokinase enzyme for inhibition of Aβ40 plaques in Alzheimer’s disease

    Science.gov (United States)

    Bhatt, Prakash Chandra; Verma, Amita; Al-Abbasi, Fahad A; Anwar, Firoz; Kumar, Vikas; Panda, Bibhu Prasad

    2017-01-01

    According to the World Health Organization, globally there are around 18 million patients suffering from Alzheimer’s disease (AD), and this number is expected to double by 2025. The pathophysiology of AD includes selective deposition of Aβ peptide in the mitochondria of cells, which inhibits uptake of glucose by neurons and key enzyme functions. Current drug treatments for AD are unable to rectify the underlying pathology of the disease; they only provide short-term symptomatic relief, so there is a need for the development of newer treatment regimes. The antiamyloid activity, antifibrinolytic activity, and antithrombotic activity of nattokinase holds potential for the treatment of AD. As nattokinase is a protein, its stability restricts its usage to a greater extent, but this limitation can be overcome by nanoencapsulation. In this work, we successfully synthesized polymeric nanoparticles of nattokinase and characterized its use by different techniques: transmission electron microscopy, scanning electron microscopy, DTS Nano, differential scanning calorimetry, Fourier-transform infrared spectroscopy, thioflavin T-binding assay, in vitro drug release, antifibrinolytic activity, and in vivo antiamyloid activity. As brain targeting of hydrophilic drugs is complicated due to the stringent nature of blood–brain barrier, in the current experimental study, we conjugated poly(lactic-co-glycolic acid) (PLGA)-encapsulated nattokinase with Tet1 peptide, which exhibits retrograde transportation properties because of its affinity to neurons. Our study suggests that PLGA-encapsulated nattokinase polymeric nanoparticles are able to downregulate amyloid aggregation and exhibit antifibrinolytic activity. The encapsulation of nattokinase in PLGA did not affect its enzyme activity, so the prepared nanoformulation containing nattokinase can be used as an effective drug treatment against AD. PMID:29263666

  19. Development of surface-engineered PLGA nanoparticulate-delivery system of Tet1-conjugated nattokinase enzyme for inhibition of Aβ40 plaques in Alzheimer's disease.

    Science.gov (United States)

    Bhatt, Prakash Chandra; Verma, Amita; Al-Abbasi, Fahad A; Anwar, Firoz; Kumar, Vikas; Panda, Bibhu Prasad

    2017-01-01

    According to the World Health Organization, globally there are around 18 million patients suffering from Alzheimer's disease (AD), and this number is expected to double by 2025. The pathophysiology of AD includes selective deposition of Aβ peptide in the mitochondria of cells, which inhibits uptake of glucose by neurons and key enzyme functions. Current drug treatments for AD are unable to rectify the underlying pathology of the disease; they only provide short-term symptomatic relief, so there is a need for the development of newer treatment regimes. The antiamyloid activity, antifibrinolytic activity, and antithrombotic activity of nattokinase holds potential for the treatment of AD. As nattokinase is a protein, its stability restricts its usage to a greater extent, but this limitation can be overcome by nanoencapsulation. In this work, we successfully synthesized polymeric nanoparticles of nattokinase and characterized its use by different techniques: transmission electron microscopy, scanning electron microscopy, DTS Nano, differential scanning calorimetry, Fourier-transform infrared spectroscopy, thioflavin T-binding assay, in vitro drug release, antifibrinolytic activity, and in vivo antiamyloid activity. As brain targeting of hydrophilic drugs is complicated due to the stringent nature of blood-brain barrier, in the current experimental study, we conjugated poly(lactic- co -glycolic acid) (PLGA)-encapsulated nattokinase with Tet1 peptide, which exhibits retrograde transportation properties because of its affinity to neurons. Our study suggests that PLGA-encapsulated nattokinase polymeric nanoparticles are able to downregulate amyloid aggregation and exhibit antifibrinolytic activity. The encapsulation of nattokinase in PLGA did not affect its enzyme activity, so the prepared nanoformulation containing nattokinase can be used as an effective drug treatment against AD.

  20. Abundant Rodent Furan-Derived Urinary Metabolites Are Associated with Tobacco Smoke Exposure in Humans.

    Science.gov (United States)

    Grill, Alex E; Schmitt, Thaddeus; Gates, Leah A; Lu, Ding; Bandyopadhyay, Dipankar; Yuan, Jian-Min; Murphy, Sharon E; Peterson, Lisa A

    2015-07-20

    Furan, a possible human carcinogen, is found in heat treated foods and tobacco smoke. Previous studies have shown that humans are capable of converting furan to its reactive metabolite, cis-2-butene-1,4-dial (BDA), and therefore may be susceptible to furan toxicity. Human risk assessment of furan exposure has been stymied because of the lack of mechanism-based exposure biomarkers. Therefore, a sensitive LC-MS/MS assay for six furan metabolites was applied to measure their levels in urine from furan-exposed rodents as well as in human urine from smokers and nonsmokers. The metabolites that result from direct reaction of BDA with lysine (BDA-N(α)-acetyllysine) and from cysteine-BDA-lysine cross-links (N-acetylcysteine-BDA-lysine, N-acetylcysteine-BDA-N(α)-acetyllysine, and their sulfoxides) were targeted in this study. Five of the six metabolites were identified in urine from rodents treated with furan by gavage. BDA-N(α)-acetyllysine, N-acetylcysteine-BDA-lysine, and its sulfoxide were detected in most human urine samples from three different groups. The levels of N-acetylcysteine-BDA-lysine sulfoxide were more than 10 times higher than that of the corresponding sulfide in many samples. The amount of this metabolite was higher in smokers relative to that in nonsmokers and was significantly reduced following smoking cessation. Our results indicate a strong relationship between BDA-derived metabolites and smoking. Future studies will determine if levels of these biomarkers are associated with adverse health effects in humans.

  1. Acetyl-Phosphate Is a Critical Determinant of Lysine Acetylation in E. coli

    DEFF Research Database (Denmark)

    Weinert, Brian T; Iesmantavicius, Vytautas; Wagner, Sebastian A

    2013-01-01

    Lysine acetylation is a frequently occurring posttranslational modification in bacteria; however, little is known about its origin and regulation. Using the model bacterium Escherichia coli (E. coli), we found that most acetylation occurred at a low level and accumulated in growth-arrested cells...... acetylate lysine residues in vitro and that AcP levels are correlated with acetylation levels in vivo, suggesting that AcP may acetylate proteins nonenzymatically in cells. These results uncover a critical role for AcP in bacterial acetylation and indicate that most acetylation in E. coli occurs at a low...

  2. Irbesartan treatment does not influence plasma levels of the advanced glycation end products N(epsilon)(1-carboxymethyl)lysine and N(epsilon)(1-carboxyethyl)lysine in patients with type 2 diabetes and microalbuminuria. A randomized controlled trial

    DEFF Research Database (Denmark)

    Engelen, Lian; Persson, Frederik; Ferreira, Isabel

    2011-01-01

    to confirm such beneficial effects of ARBs on AGEs are lacking. Therefore, we investigated the effects of irbesartan treatment on plasma levels of the AGEs N(e)(1-carboxymethyl)lysine (CML) and N(e)(1-carboxyethyl)lysine (CEL) in hypertensive patients with type 2 diabetes and microalbuminuria. METHODS: We...... and -0.10 µmol/mol lysine (-0.76 to 0.56) for CEL. CONCLUSIONS: Long-term irbesartan treatment does not influence plasma levels of the AGE CML and CEL in patients with type 2 diabetes and microalbuminuria.......BACKGROUND: In vitro and animal experiments have shown inhibiting effects of angiotensin receptor blockers (ARBs) on the formation of advanced glycation end products (AGEs), which are known to be involved in the development of cardiovascular complications in diabetes. However, sufficient human data...

  3. Boosting Anaplerotic Reactions by Pyruvate Kinase Gene Deletion and Phosphoenolpyruvate Carboxylase Desensitization for Glutamic Acid and Lysine Production in Corynebacterium glutamicum.

    Science.gov (United States)

    Yokota, Atsushi; Sawada, Kazunori; Wada, Masaru

    In the 1980s, Shiio and coworkers demonstrated using random mutagenesis that the following three phenotypes were effective for boosting lysine production by Corynebacterium glutamicum: (1) low-activity-level citrate synthase (CS L ), (2) phosphoenolpyruvate carboxylase (PEPC) resistant to feedback inhibition by aspartic acid (PEPC R ), and (3) pyruvate kinase (PYK) deficiency. Here, we reevaluated these phenotypes and their interrelationship in lysine production using recombinant DNA techniques.The pyk deletion and PEPC R (D299N in ppc) independently showed marginal effects on lysine production, but both phenotypes synergistically increased lysine yield, demonstrating the importance of PEPC as an anaplerotic enzyme in lysine production. Similar effects were also found for glutamic acid production. CS L (S252C in gltA) further increased lysine yield. Thus, using molecular techniques, the combination of these three phenotypes was reconfirmed to be effective for lysine production. However, a simple CS L mutant showed instabilities in growth and lysine yield.Surprisingly, the pyk deletion was found to increase biomass production in wild-type C. glutamicum ATCC13032 under biotin-sufficient conditions. The mutant showed a 37% increase in growth (based on OD 660 ) compared with the ATCC13032 strain in a complex medium containing 100 g/L glucose. Metabolome analysis revealed the intracellular accumulation of excess precursor metabolites. Thus, their conversion into biomass was considered to relieve the metabolic distortion in the pyk-deleted mutant. Detailed physiological studies of various pyk-deleted mutants also suggested that malate:quinone oxidoreductase (MQO) is important to control both the intracellular oxaloacetic acid (OAA) level and respiration rate. These findings may facilitate the rational use of C. glutamicum in fermentation industries.

  4. Effect of lysine addition on growth of black iguana (Ctenosaura pectinata).

    Science.gov (United States)

    Guzmán, Juan José Ortiz; Luis, Arcos-García José; Martínez, Germán D Mendoza; Pérez, Fernando Xicoténcatl Plata; Mascorro, Gisela Fuentes; Inzunza, Gabriela Ruelas

    2013-01-01

    The effects of the addition of lysine to commercial feed given to captive black iguana (Ctenosaura pectinata) were evaluated in terms of growth and feed digestibility. Twenty-eight-day-old black iguana with an initial weight of 5.5 ± 0.3 g were housed individually in cages measuring 45 × 45 × 45 cm. The experiment lasted 150 days. The ambient temperature ranged from 28 to 35°C with a relative humidity of 60 to 95%. Treatments consisted of the addition of different percentages of lysine to the feed (0.0, 0.1, 0.2, and 0.3%, dry matter [DM] base). There was a linear response (P iguana diet in the first months of life is important to stimulate growth and intake. © 2012 Wiley Periodicals, Inc.

  5. Metabolically stable bradykinin B2 receptor agonists enhance transvascular drug delivery into malignant brain tumors by increasing drug half-life

    Directory of Open Access Journals (Sweden)

    Glen Daniel

    2009-05-01

    Full Text Available Abstract Background The intravenous co-infusion of labradimil, a metabolically stable bradykinin B2 receptor agonist, has been shown to temporarily enhance the transvascular delivery of small chemotherapy drugs, such as carboplatin, across the blood-brain tumor barrier. It has been thought that the primary mechanism by which labradimil does so is by acting selectively on tumor microvasculature to increase the local transvascular flow rate across the blood-brain tumor barrier. This mechanism of action does not explain why, in the clinical setting, carboplatin dosing based on patient renal function over-estimates the carboplatin dose required for target carboplatin exposure. In this study we investigated the systemic actions of labradimil, as well as other bradykinin B2 receptor agonists with a range of metabolic stabilities, in context of the local actions of the respective B2 receptor agonists on the blood-brain tumor barrier of rodent malignant gliomas. Methods Using dynamic contrast-enhanced MRI, the pharmacokinetics of gadolinium-diethyltriaminepentaacetic acid (Gd-DTPA, a small MRI contrast agent, were imaged in rodents bearing orthotopic RG-2 malignant gliomas. Baseline blood and brain tumor tissue pharmacokinetics were imaged with the 1st bolus of Gd-DTPA over the first hour, and then re-imaged with a 2nd bolus of Gd-DTPA over the second hour, during which normal saline or a bradykinin B2 receptor agonist was infused intravenously for 15 minutes. Changes in mean arterial blood pressure were recorded. Imaging data was analyzed using both qualitative and quantitative methods. Results The decrease in systemic blood pressure correlated with the known metabolic stability of the bradykinin B2 receptor agonist infused. Metabolically stable bradykinin B2 agonists, methionine-lysine-bradykinin and labradimil, had differential effects on the transvascular flow rate of Gd-DTPA across the blood-brain tumor barrier. Both methionine-lysine

  6. Tranexamic acid treatment of hemothorax in two patients with malignant mesothelioma

    NARCIS (Netherlands)

    de Boer, W. A.; Koolen, M. G.; Roos, C. M.; ten Cate, J. W.

    1991-01-01

    Patients with malignant mesothelioma may present with hemothorax. We used a combination of oral and intrapleural tranexamic acid to treat two patients with this severe complication. Initiation of treatment with this potent anti-fibrinolytic drug resulted in rapid reduction of bleeding and of

  7. Tranexamic Acid Does Not Influence Cardioprotection by Ischemic Preconditioning and Remote Ischemic Preconditioning

    NARCIS (Netherlands)

    van Caster, Patrick; Eiling, Sandra; Boekholt, Yvonne; Behmenburg, Friederike; Dorsch, Marianne; Heinen, André; Hollmann, Markus W.; Huhn, Ragnar

    2018-01-01

    Prior studies have suggested that the antifibrinolytic drug aprotinin increases the infarct size after ischemia and reperfusion (I/R) and attenuates the effect of ischemic preconditioning (IPC). Aprotinin was replaced by tranexamic acid (TXA) in clinical practice. Here, we investigated whether TXA

  8. Quantification of Lysine Acetylation and Succinylation Stoichiometry in Proteins Using Mass Spectrometric Data-Independent Acquisitions (SWATH)

    Science.gov (United States)

    Meyer, Jesse G.; D'Souza, Alexandria K.; Sorensen, Dylan J.; Rardin, Matthew J.; Wolfe, Alan J.; Gibson, Bradford W.; Schilling, Birgit

    2016-11-01

    Post-translational modification of lysine residues by NƐ-acylation is an important regulator of protein function. Many large-scale protein acylation studies have assessed relative changes of lysine acylation sites after antibody enrichment using mass spectrometry-based proteomics. Although relative acylation fold-changes are important, this does not reveal site occupancy, or stoichiometry, of individual modification sites, which is critical to understand functional consequences. Recently, methods for determining lysine acetylation stoichiometry have been proposed based on ratiometric analysis of endogenous levels to those introduced after quantitative per-acetylation of proteins using stable isotope-labeled acetic anhydride. However, in our hands, we find that these methods can overestimate acetylation stoichiometries because of signal interferences when endogenous levels of acylation are very low, which is especially problematic when using MS1 scans for quantification. In this study, we sought to improve the accuracy of determining acylation stoichiometry using data-independent acquisition (DIA). Specifically, we use SWATH acquisition to comprehensively collect both precursor and fragment ion intensity data. The use of fragment ions for stoichiometry quantification not only reduces interferences but also allows for determination of site-level stoichiometry from peptides with multiple lysine residues. We also demonstrate the novel extension of this method to measurements of succinylation stoichiometry using deuterium-labeled succinic anhydride. Proof of principle SWATH acquisition studies were first performed using bovine serum albumin for both acetylation and succinylation occupancy measurements, followed by the analysis of more complex samples of E. coli cell lysates. Although overall site occupancy was low (<1%), some proteins contained lysines with relatively high acetylation occupancy.

  9. Tranexamic acid–associated seizures: Causes and treatment

    Science.gov (United States)

    Lecker, Irene; Wang, Dian‐Shi; Whissell, Paul D.; Avramescu, Sinziana; Mazer, C. David

    2015-01-01

    Antifibrinolytic drugs are routinely used worldwide to reduce the bleeding that results from a wide range of hemorrhagic conditions. The most commonly used antifibrinolytic drug, tranexamic acid, is associated with an increased incidence of postoperative seizures. The reported increase in the frequency of seizures is alarming, as these events are associated with adverse neurological outcomes, longer hospital stays, and increased in‐hospital mortality. However, many clinicians are unaware that tranexamic acid causes seizures. The goal of this review is to summarize the incidence, risk factors, and clinical features of these seizures. This review also highlights several clinical and preclinical studies that offer mechanistic insights into the potential causes of and treatments for tranexamic acid–associated seizures. This review will aid the medical community by increasing awareness about tranexamic acid–associated seizures and by translating scientific findings into therapeutic interventions for patients. ANN NEUROL 2016;79:18–26 PMID:26580862

  10. "Drug" Discovery with the Help of Organic Chemistry.

    Science.gov (United States)

    Itoh, Yukihiro; Suzuki, Takayoshi

    2017-01-01

    The first step in "drug" discovery is to find compounds binding to a potential drug target. In modern medicinal chemistry, the screening of a chemical library, structure-based drug design, and ligand-based drug design, or a combination of these methods, are generally used for identifying the desired compounds. However, they do not necessarily lead to success and there is no infallible method for drug discovery. Therefore, it is important to explore medicinal chemistry based on not only the conventional methods but also new ideas. So far, we have found various compounds as drug candidates. In these studies, some strategies based on organic chemistry have allowed us to find drug candidates, through 1) construction of a focused library using organic reactions and 2) rational design of enzyme inhibitors based on chemical reactions catalyzed by the target enzyme. Medicinal chemistry based on organic chemical reactions could be expected to supplement the conventional methods. In this review, we present drug discovery with the help of organic chemistry showing examples of our explorative studies on histone deacetylase inhibitors and lysine-specific demethylase 1 inhibitors.

  11. Non-enzymatic N-acetylation of Lysine Residues by AcetylCoA Often Occurs via a Proximal S-acetylated Thiol Intermediate Sensitive to Glyoxalase II.

    Science.gov (United States)

    James, Andrew M; Hoogewijs, Kurt; Logan, Angela; Hall, Andrew R; Ding, Shujing; Fearnley, Ian M; Murphy, Michael P

    2017-02-28

    Acetyl coenzyme A (AcCoA), a key intermediate in mitochondrial metabolism, N-acetylates lysine residues, disrupting and, in some cases, regulating protein function. The mitochondrial lysine deacetylase Sirtuin 3 (Sirt3) reverses this modification with benefits reported in diabetes, obesity, and aging. We show that non-enzymatic lysine N-acetylation by AcCoA is greatly enhanced by initial acetylation of a cysteine residue, followed by SN-transfer of the acetyl moiety to a nearby lysine on mitochondrial proteins and synthetic peptides. The frequent occurrence of an S-acetyl intermediate before lysine N-acetylation suggests that proximity to a thioester is a key determinant of lysine susceptibility to acetylation. The thioesterase glyoxalase II (Glo2) can limit protein S-acetylation, thereby preventing subsequent lysine N-acetylation. This suggests that the hitherto obscure role of Glo2 in mitochondria is to act upstream of Sirt3 in minimizing protein N-acetylation, thus limiting protein dysfunction when AcCoA accumulates. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Lysine and Leucine Deficiencies Affect Myocytes Development and IGF Signaling in Gilthead Sea Bream (Sparus aurata.

    Directory of Open Access Journals (Sweden)

    Sheida Azizi

    Full Text Available Optimizing aquaculture production requires better knowledge of growth regulation and improvement in diet formulation. A great effort has been made to replace fish meal for plant protein sources in aquafeeds, making necessary the supplementation of such diets with crystalline amino acids (AA to cover the nutritional requirements of each species. Lysine and Leucine are limiting essential AA in fish, and it has been demonstrated that supplementation with them improves growth in different species. However, the specific effects of AA deficiencies in myogenesis are completely unknown and have only been studied at the level of hepatic metabolism. It is well-known that the TOR pathway integrates the nutritional and hormonal signals to regulate protein synthesis and cell proliferation, to finally control muscle growth, a process also coordinated by the expression of myogenic regulatory factors (MRFs. This study aimed to provide new information on the impact of Lysine and Leucine deficiencies in gilthead sea bream cultured myocytes examining their development and the response of insulin-like growth factors (IGFs, MRFs, as well as key molecules involved in muscle growth regulation like TOR. Leucine deficiency did not cause significant differences in most of the molecules analyzed, whereas Lysine deficiency appeared crucial in IGFs regulation, decreasing significantly IGF-I, IGF-II and IGF-IRb mRNA levels. This treatment also down-regulated the gene expression of different MRFs, including Myf5, Myogenin and MyoD2. These changes were also corroborated by a significant decrease in proliferation and differentiation markers in the Lysine-deficient treatment. Moreover, both Lysine and Leucine limitation induced a significant down-regulation in FOXO3 gene expression, which deserves further investigation. We believe that these results will be relevant for the production of a species as appreciated for human consumption as it is gilthead sea bream and demonstrates

  13. Gastrointestinal blood loss induced by three different non-steroidal anti-inflammatory drugs.

    Science.gov (United States)

    Bidlingmaier, A; Hammermaier, A; Nagyiványi, P; Pabst, G; Waitzinger, J

    1995-04-01

    A clinical study was performed on 18 healthy volunteers to compare the gastrointestinal daily blood loss induced by oral intake of three different non-steroidal anti-inflammatory drugs, lysine clonixinate (CAS 55837-30-4), ibuprofen (CAS 15687-27-1) and acetylsalicylic acid (CAS 50-78-2 ASA). For quantitative determination of gastrointestinal blood loss, autologous erythrocytes were radiolabelled in vitro with 51Cr and reinfused at study start. The amount of radioactivity excreted in faeces was measured during a placebo baseline phase of three days, a treatment phase of five days with thrice daily dosing of ASA, ibuprofen or lysine clonixinate and a subsequent wash-out phase of five days. The highest increase of mean daily blood loss over baseline was observed after treatment with ASA (+ 1.66 ml/d versus baseline). Treatment with ibuprofen led to an increase of mean daily blood loss by + 0.52 ml/d. During treatment with lysine clonixinate the mean increase of daily blood loss was +0.32 ml/d versus baseline. In the ibuprofen and lysine clonixinate treatment groups the values of mean daily blood loss decreased during the wash-out phase with respect to the verum phase, whereas the mean daily blood loss during the wash-out phase after treatment with ASA even increased in comparison to the verum phase (mean daily blood loss: +2.07 ml/d versus baseline.

  14. The effects of acute morphine treatment on the incorporation of [3H]L-lysine by normal and regenerating facial nucleus neurons

    International Nuclear Information System (INIS)

    Sinatra, R.S.; Ford, D.H.; Rhines, R.K.

    1979-01-01

    The effect of morphine on the incorporation of [ 3 H]L-lysine into proteins of facial nucleus neurons was examined by light microscopic radioautography. Silver grains present within various compartments of normal and regenerating (3-, 7-. 14- and 21 days post-axotomy) neurons from saline-treated Wistar rats were compared with the amount present in similar cells from animals receiving 40 mg/kg morphine sulfate i.v. At 14- and 21-days post-axotomy, regenerating neurons were larger and the grain count in the emulsion over these cells was greater than that observed in normal (unoperated) neurons. In normal facial neurons, the accumulation of lysine into the nucleus and nucleolus was significantly lower 60 min after morphine adminstration. However, morphine's inhibition of lysine incorporation was even more pronounced in regenerating neurons. In these cells, nuclear lysine uptake was depressed at 3 and 7 days, while maximum inhibition of cytoplasmic incorporation occurred at 14-days post-axotomy. Morphine adminstration decreased nucleolar lysine incorporation at all survival intervals. (Auth.)

  15. Site-specific antibody-drug conjugates: the nexus of bioorthogonal chemistry, protein engineering, and drug development.

    Science.gov (United States)

    Agarwal, Paresh; Bertozzi, Carolyn R

    2015-02-18

    Antibody-drug conjugates (ADCs) combine the specificity of antibodies with the potency of small molecules to create targeted drugs. Despite the simplicity of this concept, generation of clinically successful ADCs has been very difficult. Over the past several decades, scientists have learned a great deal about the constraints on antibodies, linkers, and drugs as they relate to successful construction of ADCs. Once these components are in hand, most ADCs are prepared by nonspecific modification of antibody lysine or cysteine residues with drug-linker reagents, which results in heterogeneous product mixtures that cannot be further purified. With advances in the fields of bioorthogonal chemistry and protein engineering, there is growing interest in producing ADCs by site-specific conjugation to the antibody, yielding more homogeneous products that have demonstrated benefits over their heterogeneous counterparts in vivo. Here, we chronicle the development of a multitude of site-specific conjugation strategies for assembly of ADCs and provide a comprehensive account of key advances and their roots in the fields of bioorthogonal chemistry and protein engineering.

  16. Sequences of digestible lysine for gilts from 60 to 148 days of age

    Directory of Open Access Journals (Sweden)

    Veredino Louzada da Silva Júnior

    2015-01-01

    Full Text Available The experiment was conducted to evaluate five nutritional plans based on sequences of standardized ileal digestible lysine: 0.90-0.80-0.70, 1.00-0.90-0.80, 1.10-1.00-0.90, 1.20-1.10-1.00, and 1.30-1.20-1.10% fed to gilts from 60 to 99, 129 to 100, and 130 to 148 days of age, respectively. Eighty commercial hybrid gilts, selected for lean gain, with initial weight of 23.46±0.27kg were allotted in a randomized block design, with five treatments, eight replicates, and two pigs per experimental unit. No effect (P>0.05 of the nutritional plans was verified on daily feed intake, daily weight gain and feed conversion. The nutritional plans had no influence (P>0.05 on any of the carcass traits evaluated (carcass yield, meat amount, and meat yield. The nutritional plan of 0.90-0.80-0.70% standardized ileal digestible lysine fed to gilts from 60 to 99, 100 to 129, and 130 to 148 days of age, respectively, meets the standardized ileal digestible lysine requirements of gilts from 60 to 148 days of age.

  17. Distinct Paths for Basic Amino Acid Export in Escherichia coli: YbjE (LysO) Mediates Export of L-Lysine.

    Science.gov (United States)

    Pathania, Amit; Sardesai, Abhijit A

    2015-06-15

    In Escherichia coli, argO encodes an exporter for L-arginine (Arg) and its toxic analogue canavanine (CAN), and its transcriptional activation and repression, by Arg and L-lysine (Lys), respectively, are mediated by the regulator ArgP. Accordingly argO and argP mutants are CAN supersensitive (CAN(ss)). We report the identification of ybjE as a gene encoding a predicted inner membrane protein that mediates export of Lys, and our results confirm the previous identification with a different approach of YbjE as a Lys exporter, reported by Ueda and coworkers (T. Ueda, Y. Nakai, Y. Gunji, R. Takikawa, and Y. Joe, U.S. patents 7,629,142 B2 [December 2009] and 8,383,363 B1 [February 2013] and European patent 1,664,318 B1 [September 2009]). ybjE was isolated as a multicopy suppressor of the CAN(ss) phenotype of a strain lacking ArgO. The absence of YbjE did not confer a CAN(ss) phenotype but instead conferred hypersensitivity to the lysine antimetabolite thialysine and led to growth inhibition by the dipeptide lysylalanine, which is associated with elevated cellular Lys content. YbjE overproduction resulted in Lys excretion and syntrophic cross-feeding of a Lys auxotroph. Constitutive overexpression of argO promoted Lys cross-feeding that is indicative of a latent Lys export potential of ArgO. Arg modestly repressed ybjE transcription in an ArgR-dependent manner, and ArgR displayed Arg-sensitive binding to the ybjE promoter region in vitro. Our studies suggest that the reciprocal repression of argO and ybjE, respectively, by Lys and Arg confers the specificity for basic amino acid export by distinct paths and that such cross-repression contributes to maintenance of cytoplasmic Arg/Lys balance. We propose that YbjE be redesignated LysO. This work ascribes a lysine export function to the product of the ybjE gene of Escherichia coli, leading to a physiological scenario wherein two proteins, ArgO and YbjE, perform the task of separately exporting arginine and lysine

  18. 21 CFR 184.1685 - Rennet (animal-derived) and chymosin preparation (fermentation-derived).

    Science.gov (United States)

    2010-04-01

    ... (fermentation-derived). 184.1685 Section 184.1685 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... (animal-derived) and chymosin preparation (fermentation-derived). (a)(1) Rennet and bovine rennet are... clear solution containing the active enzyme chymosin (E.C. 3.4.23.4). It is derived, via fermentation...

  19. Non-enzymatic N -acetylation of Lysine Residues by AcetylCoA Often Occurs via a Proximal S -acetylated Thiol Intermediate Sensitive to Glyoxalase II

    OpenAIRE

    James, Andrew M.; Hoogewijs, Kurt; Logan, Angela; Hall, Andrew R.; Ding, Shujing; Fearnley, Ian M.; Murphy, Michael P.

    2017-01-01

    Summary: Acetyl coenzyme A (AcCoA), a key intermediate in mitochondrial metabolism, N-acetylates lysine residues, disrupting and, in some cases, regulating protein function. The mitochondrial lysine deacetylase Sirtuin 3 (Sirt3) reverses this modification with benefits reported in diabetes, obesity, and aging. We show that non-enzymatic lysine N-acetylation by AcCoA is greatly enhanced by initial acetylation of a cysteine residue, followed by SN-transfer of the acetyl moiety to a nearby lysin...

  20. Lysine and Glutamic Acids as the End Products of Multi-response of Optimized Fermented Medium by Mucor mucedo KP736529.

    Science.gov (United States)

    El-Hersh, Mohammed S; Saber, WesamEldin I A; El-Fadaly, Husain A; Mahmoud, Mohammed K

    Amino acids are important for living organisms, they acting as crucial for metabolic activities and energy generation, wherein the deficiency in these amino acids cause various physiological defects. The aim of this study is to investigate the effect of some nutritional factors on the amino acids production by Mucor mucedo KP736529 during fermentation intervals. Mucor mucedo KP736529 was selected according to proteolytic activity. Corn steep liquor and olive cake were used in the fermented medium during Placket-Burman and central composite design to maximize the production of lysine and glutamic acids. During the screening by Plackett-Burman design, olive cake and Corn Steep Liquor (CSL) had potential importance for the higher production of amino acids. The individual fractionation of total amino acids showed both lysine and glutamic as the major amino acids associated with the fermentation process. Moreover, the Central Composite Design (CCD) has been adopted to explain the interaction between olive cake and CSL on the production of lysine and glutamic acids. The model recorded significant F-value, with high values of R 2, adjusted R 2 and predicted R 2 for both lysine and glutamic, indicating the validity of the data. Solving equation for maximum production of lysine recorded theoretical levels of olive cake and CSL, being 2.58 and 1.83 g L -1, respectively, with predicting value of lysine at 1.470 μg mL -1, whereas the predicting value of glutamic acid reached 0.805 mg mL -1 at levels of 2.49 and 1.93 g L -1 from olive cake and CSL, respectively. The desirability function (D) showed the actual responses being 1.473±0.009 and 0.801±0.004 μg mL -1 for lysine and glutamic acids, respectively. The model showed adequate validity to be applied in a large-scale production of both lysine and glutamic acids.

  1. In-Silico Study Of Water Soluble C60-Fullerene Derivatives And Different Drug Targets

    Directory of Open Access Journals (Sweden)

    Mohammad Teimouri

    2015-08-01

    Full Text Available Fullerene C60 is a unique carbon molecule that adopts a sphere shape. It has been proved that fullerene and some of its derivatives several disease targets. Fullerene itself is insoluble in water. So fullerene application is hindered in medical field. In this study a literature search was performed and all derivatives were collected. The fullerene binding protein previously reported in literature were also retrieved from protein databank. The docking study were performed with fullerene derivatives and its binding proteins. The selected proteins include Voltage-Gated Potassium Channel estrogenic 17beta-hydroxysteroid dehydrogenase and monoclonal anti-progesterone antibody. The binding affinity and binding free energy were computed for these proteins and fullerene derivatives complexes. The binding affinity and binding free energy calculation of the co-crystal ligands were also carried out. The results show the good fitting of fullerene derivatives in the active site of different proteins. The binding affinities and binding free energies of fullerene derivatives are better. The present study gives a detail information about the binding mode of C60 derivatives. The finding will be helpful in fullerene-based drug discovery and facilitate the efforts of fighting many diseases.

  2. Bioequivalence of 250 mg lysine clonixinate tablets after a single oral dose in a healthy female Mexican population under fasting conditions.

    Science.gov (United States)

    Marcelín-Jiménez, G; Angeles, A C P; García, A; Morales, M; Rivera, L; Martín-Del-Campo, A

    2010-05-01

    To evaluate the bioequivalence between two 250 mg-tablets of lysine clonixinate, Dorixina Forte (Siegfried Rhein, México) as reference product, and Prestodol (Farmaceúticos Rayere, S.A., México) as test formulation. 26 healthy adult female Mexican volunteers received a single oral dose of 250-mg lysine clonixinate under fasting conditions. The drug was administered following a randomized, two-period, two-sequence, cross-over design. Twelve serial blood samples were collected up to 8 h after dosing, and clonixin (CLX) was measured by ultra-performance liquid chromatography (UPLC) coupled with tandem mass spectrometry. Decimal logarithm values of Cmax and area under the curve (AUC) were used to construct a classic confidence interval at 90% (90% CI). Bioequivalence was established if 90% CI of mean ratios (test/reference) fall within the 0.8-1.25 range. Volunteers formed a homogeneous population in terms of age (27.2 +/- 6.3 years), weight (55.9 +/- 6.5 kg), height (1.6 +/- 0.04 m), and body mass index (BMI) (22.91 +/- 2.03 kg/m(2)). Reference formulation exhibited the following pharmacokinetics: C(max) (32.39 +/- 8.32 microg/ml); t(max) (0.64 +/- 0.2 h); AUC0-8h (48.92 +/- 16.51 microg x h/ml); t1/2 (1.3 +/- 0.24 h); CLapp (5.64 +/- 1.99 l/h), and Vdapp (10.22 +/- 2.9 l). Concerning bioequivalence, 90% CI were: C(max) (82.32 - 98.79), AUC0-t (94.59-106.29), and AUC(0-inf) (94.61-106.42), with a statistical power of > 0.90 at every tested interval. This single-dose study found that both 250-mg immediate-release tablets of lysine clonixinate met the Mexican regulatory criteria for bioequivalence in these volunteers.

  3. Therapeutic use of chimeric bacteriophage (phage) lysins in staphylococcal endophthalmitis

    Science.gov (United States)

    Purpose: Phage endolysins are peptidoglycan hydrolases that are produced at the end of the phage lytic cycle to digest the host bacterial cell wall, facilitating the release of mature phage progeny. The aim of this study is to determine the antimicrobial activity of chimeric phage lysins against cli...

  4. Monitoring lysin motif-ligand interactions via tryptophan analog fluorescence spectroscopy

    NARCIS (Netherlands)

    Petrovic, Dejan M.; Leenhouts, Kees; van Roosmalen, Maarten L.; KleinJan, Fenneke; Broos, Jaap

    2012-01-01

    The lysin motif (LysM) is a peptidoglycan binding protein domain found in a wide range of prokaryotes and eukaryotes. Various techniques have been used to study the LysM-ligand interaction, but a sensitive spectroscopic method to directly monitor this interaction has not been reported. Here a

  5. Increased expression of pyruvate carboxylase and biotin protein ligase increases lysine production in a biotin prototrophic Corynebacterium glutamicum strain

    DEFF Research Database (Denmark)

    Wang, Zhihao; Moslehi-Jenabian, Soloomeh; Solem, Christian

    2015-01-01

    , and achieved biotin prototrophy. We found that AHP-3, containing pBIO, was able to produce lysine in a medium lacking biotin and that the lysine yield on glucose was similar to what is obtained when using a medium containing biotin. However, there was a decrease in specific growth rate of 20% when the strain...... pimeloyl-Acyl Carrier Protein [ACP]) formation. Pyruvate carboxylase (pycA), a biotin-dependent enzyme needed for lysine biosynthesis and biotin ligase (birA), which is responsible for attaching biotin to pyruvate carboxylase, were overexpressed by replacing the native promoters with the strong superoxide...... dismutase (sod) promoter, to see whether growth could be restored. Neither pycA nor birA overexpression, whether alone or in combination, had an effect on specific growth rate, but they did have a positive effect on lysine yield, which increased by 55% in the strain overexpressing both enzymes....

  6. N-epsilon-(carboxyethyl)lysine, a product of the chemical modification of proteins by methylglyoxal, increases with age in human lens proteins.

    OpenAIRE

    Ahmed, M U; Brinkmann Frye, E; Degenhardt, T P; Thorpe, S R; Baynes, J W

    1997-01-01

    Advanced glycation end-products and glycoxidation products, such as Nepsilon-(carboxymethyl)lysine (CML) and pentosidine, accumulate in long-lived tissue proteins with age and are implicated in the aging of tissue proteins and in the development of pathology in diabetes, atherosclerosis and other diseases. In this paper we describe a new advanced glycation end-product, Nepsilon-(carboxyethyl)lysine (CEL), which is formed during the reaction of methylglyoxal with lysine residues in model compo...

  7. The conserved Lysine69 residue plays a catalytic role in Mycobacterium tuberculosis shikimate dehydrogenase

    Directory of Open Access Journals (Sweden)

    Rodrigues Valnês

    2009-01-01

    Full Text Available Abstract Background The shikimate pathway is an attractive target for the development of antitubercular agents because it is essential in Mycobacterium tuberculosis, the causative agent of tuberculosis, but absent in humans. M. tuberculosis aroE-encoded shikimate dehydrogenase catalyzes the forth reaction in the shikimate pathway. Structural and functional studies indicate that Lysine69 may be involved in catalysis and/or substrate binding in M. tuberculosis shikimate dehydrogenase. Investigation of the kinetic properties of mutant enzymes can bring important insights about the role of amino acid residues for M. tuberculosis shikimate dehydrogenase. Findings We have performed site-directed mutagenesis, steady-state kinetics, equilibrium binding measurements and molecular modeling for both the wild-type M. tuberculosis shikimate dehydrogenase and the K69A mutant enzymes. The apparent steady-state kinetic parameters for the M. tuberculosis shikimate dehydrogenase were determined; the catalytic constant value for the wild-type enzyme (50 s-1 is 68-fold larger than that for the mutant K69A (0.73 s-1. There was a modest increase in the Michaelis-Menten constant for DHS (K69A = 76 μM; wild-type = 29 μM and NADPH (K69A = 30 μM; wild-type = 11 μM. The equilibrium dissociation constants for wild-type and K69A mutant enzymes are 32 (± 4 μM and 134 (± 21, respectively. Conclusion Our results show that the residue Lysine69 plays a catalytic role and is not involved in substrate binding for the M. tuberculosis shikimate dehydrogenase. These efforts on M. tuberculosis shikimate dehydrogenase catalytic mechanism determination should help the rational design of specific inhibitors, aiming at the development of antitubercular drugs.

  8. Drug-loaded nanoparticles induce gene expression in human pluripotent stem cell derivatives

    Science.gov (United States)

    Gajbhiye, Virendra; Escalante, Leah; Chen, Guojun; Laperle, Alex; Zheng, Qifeng; Steyer, Benjamin; Gong, Shaoqin; Saha, Krishanu

    2013-12-01

    Tissue engineering and advanced manufacturing of human stem cells requires a suite of tools to control gene expression spatiotemporally in culture. Inducible gene expression systems offer cell-extrinsic control, typically through addition of small molecules, but small molecule inducers typically contain few functional groups for further chemical modification. Doxycycline (DXC), a potent small molecule inducer of tetracycline (Tet) transgene systems, was conjugated to a hyperbranched dendritic polymer (Boltorn H40) and subsequently reacted with polyethylene glycol (PEG). The resulting PEG-H40-DXC nanoparticle exhibited pH-sensitive drug release behavior and successfully controlled gene expression in stem-cell-derived fibroblasts with a Tet-On system. While free DXC inhibited fibroblast proliferation and matrix metalloproteinase (MMP) activity, PEG-H40-DXC nanoparticles maintained higher fibroblast proliferation levels and MMP activity. The results demonstrate that the PEG-H40-DXC nanoparticle system provides an effective tool to controlling gene expression in human stem cell derivatives.Tissue engineering and advanced manufacturing of human stem cells requires a suite of tools to control gene expression spatiotemporally in culture. Inducible gene expression systems offer cell-extrinsic control, typically through addition of small molecules, but small molecule inducers typically contain few functional groups for further chemical modification. Doxycycline (DXC), a potent small molecule inducer of tetracycline (Tet) transgene systems, was conjugated to a hyperbranched dendritic polymer (Boltorn H40) and subsequently reacted with polyethylene glycol (PEG). The resulting PEG-H40-DXC nanoparticle exhibited pH-sensitive drug release behavior and successfully controlled gene expression in stem-cell-derived fibroblasts with a Tet-On system. While free DXC inhibited fibroblast proliferation and matrix metalloproteinase (MMP) activity, PEG-H40-DXC nanoparticles maintained

  9. Clinical Drug-Drug Pharmacokinetic Interaction Potential of Sucralfate with Other Drugs

    DEFF Research Database (Denmark)

    Sulochana, Suresh P; Syed, Muzeeb; Chandrasekar, Devaraj V

    2016-01-01

    of drugs. This review covers several category of drugs such as non-steroidal anti-inflammatory drugs, fluoroquinolones, histamine H2-receptor blockers, macrolides, anti-fungals, anti-diabetics, salicylic acid derivatives, steroidal anti-inflammatory drugs and provides pharmacokinetic data summary along...

  10. Synthesis and characterization of in situ photogelable polysaccharide derivative for drug delivery.

    Science.gov (United States)

    Hu, Rong; Chen, Yu-Yun; Zhang, Li-Ming

    2010-06-30

    A novel polysaccharide derivative with photoreactivity was prepared by the conjugation of carboxymethylated chitosan with N-hydroxyl succinimide-activated nitrocinnamate in the presence of N,N-dicyclohexylcarbodiimide, and characterized by IR, (1)H NMR, UV-vis and rheological analyses. It was found that such a modified polysaccharide could exhibit an unique photogelation ability in the absence of potentially toxic photoinitiator or catalyst and be suitable particularly for the in situ preparation of photocrosslinked hydrogel biomaterials. By changing the photoirradiation time and incorporated nitrocinnamate content, its photogelation property could be modulated. For the resultant hydrogels incorporated with various nitrocinnamate contents, their properties such as swelling, viscoelasticity, in vitro biodegradation and drug release were investigated. In addition, the photogelation mechanism of this polysaccharide derivative was also discussed. 2010 Elsevier B.V. All rights reserved.

  11. Basophil histamine release to Amoxicilloyl-poly-L-lysine compared to amoxicillin in patients with IgE-mediated allergic reactions to amoxicillin

    DEFF Research Database (Denmark)

    Arribas, F; Falkencrone, S; Sola, J

    2017-01-01

    BACKGROUND: Amoxicillin (AX) is the betalactam most often involved in IgE-mediated reactions and the diagnosis is mainly based on skin testing (ST) although without optimal sensitivity. We have produced a newly AX derivative, amoxicilloyl-poly-L-lysine (APL), and have analysed its IgE recognition...... with AX or APL. Histamine released was determined and expressed as ng of histamine release/mL blood. RESULTS: Patients clinical symptoms were anaphylaxis (N=9), urticaria (N=7), erythema (N=2) and not defined immediate reactions (N=1). The median time interval between reaction and study was 90 days (IQR...

  12. Human iPSC-Derived Neural Progenitors Are an Effective Drug Discovery Model for Neurological mtDNA Disorders.

    Science.gov (United States)

    Lorenz, Carmen; Lesimple, Pierre; Bukowiecki, Raul; Zink, Annika; Inak, Gizem; Mlody, Barbara; Singh, Manvendra; Semtner, Marcus; Mah, Nancy; Auré, Karine; Leong, Megan; Zabiegalov, Oleksandr; Lyras, Ekaterini-Maria; Pfiffer, Vanessa; Fauler, Beatrix; Eichhorst, Jenny; Wiesner, Burkhard; Huebner, Norbert; Priller, Josef; Mielke, Thorsten; Meierhofer, David; Izsvák, Zsuzsanna; Meier, Jochen C; Bouillaud, Frédéric; Adjaye, James; Schuelke, Markus; Wanker, Erich E; Lombès, Anne; Prigione, Alessandro

    2017-05-04

    Mitochondrial DNA (mtDNA) mutations frequently cause neurological diseases. Modeling of these defects has been difficult because of the challenges associated with engineering mtDNA. We show here that neural progenitor cells (NPCs) derived from human induced pluripotent stem cells (iPSCs) retain the parental mtDNA profile and exhibit a metabolic switch toward oxidative phosphorylation. NPCs derived in this way from patients carrying a deleterious homoplasmic mutation in the mitochondrial gene MT-ATP6 (m.9185T>C) showed defective ATP production and abnormally high mitochondrial membrane potential (MMP), plus altered calcium homeostasis, which represents a potential cause of neural impairment. High-content screening of FDA-approved drugs using the MMP phenotype highlighted avanafil, which we found was able to partially rescue the calcium defect in patient NPCs and differentiated neurons. Overall, our results show that iPSC-derived NPCs provide an effective model for drug screening to target mtDNA disorders that affect the nervous system. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Detection of salt bridges to lysines in solution in barnase

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Williamson, Michael P.; Hounslow, Andrea M.

    2013-01-01

    We show that salt bridges involving lysines can be detected by deuterium isotope effects on NMR chemical shifts of the sidechain amine. Lys27 in the ribonuclease barnase is salt bridged, and mutation of Arg69 to Lys retains a partially buried salt bridge. The salt bridges are functionally important....

  14. Metabolism-oriented amino acid requirement determination by means of the catabolic rates of 14C- and 15N-labelled lysine under maintenance

    International Nuclear Information System (INIS)

    Simon, O.; Bergner, H.; Adam, K.

    1977-01-01

    Male Wistar rats (of 60 g live weight) allotted in 10 groups were fed diets with gradually increasing lysine levels ranging from 1.4 to 7.4 g lysine/16 g N. Feed intake was restricted so much that the experimental animals did not change their live weights during the last 3 days of the 8-day experimental period. On the 7the experimental day, 4 animals of each group were injected, i. p. 14 C-L-lysine, the 14 CO 2 -excretion being subsequently measured over a period of 2 hours. On the next day, 6 animals of each group were applied an i. p. injection of 15 N-L-lysine, the urine being collected over the following 24-hour period to measure the 15 N-frequency. Applying both labelling methods, an increased catabolisation of the amino acid was observed after the metabolically necessary lysine requirement had been covered. The methods are very sensitive and revealed, under the experimental conditions chosen, a lysine requirement coverage of about 3 g lysine/16 g N. The possibility of using also 15 N-labelled compounds in the metabolism-oriented amino acid requirement determination is likely to facilitate the transfer of the methodology to farm animals would thus allow to study the amino acid requirement of man. The metabolism-oriented amino acid requirement determination will likewise allow to estimate exact amino acid requirement data under conditions that cannot be rated on the basis of productive yields. (author)

  15. Effects of lysine residues on structural characteristics and stability of tau proteins

    International Nuclear Information System (INIS)

    Lee, Myeongsang; Baek, Inchul; Choi, Hyunsung; Kim, Jae In; Na, Sungsoo

    2015-01-01

    Pathological amyloid proteins have been implicated in neuro-degenerative diseases, specifically Alzheimer's, Parkinson's, Lewy-body diseases and prion related diseases. In prion related diseases, functional tau proteins can be transformed into pathological agents by environmental factors, including oxidative stress, inflammation, Aβ-mediated toxicity and covalent modification. These pathological agents are stable under physiological conditions and are not easily degraded. This un-degradable characteristic of tau proteins enables their utilization as functional materials to capturing the carbon dioxides. For the proper utilization of amyloid proteins as functional materials efficiently, a basic study regarding their structural characteristic is necessary. Here, we investigated the basic tau protein structure of wild-type (WT) and tau proteins with lysine residues mutation at glutamic residue (Q2K) on tau protein at atomistic scale. We also reported the size effect of both the WT and Q2K structures, which allowed us to identify the stability of those amyloid structures. - Highlights: • Lysine mutation effect alters the structure conformation and characteristic of tau. • Over the 15 layers both WT and Q2K models, both tau proteins undergo fractions. • Lysine mutation causes the increment of non-bonded energy and solvent accessible surface area. • Structural instability of Q2K model was proved by the number of hydrogen bonds analysis.

  16. Effects of lysine residues on structural characteristics and stability of tau proteins

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Myeongsang; Baek, Inchul; Choi, Hyunsung; Kim, Jae In; Na, Sungsoo, E-mail: nass@korea.ac.kr

    2015-10-23

    Pathological amyloid proteins have been implicated in neuro-degenerative diseases, specifically Alzheimer's, Parkinson's, Lewy-body diseases and prion related diseases. In prion related diseases, functional tau proteins can be transformed into pathological agents by environmental factors, including oxidative stress, inflammation, Aβ-mediated toxicity and covalent modification. These pathological agents are stable under physiological conditions and are not easily degraded. This un-degradable characteristic of tau proteins enables their utilization as functional materials to capturing the carbon dioxides. For the proper utilization of amyloid proteins as functional materials efficiently, a basic study regarding their structural characteristic is necessary. Here, we investigated the basic tau protein structure of wild-type (WT) and tau proteins with lysine residues mutation at glutamic residue (Q2K) on tau protein at atomistic scale. We also reported the size effect of both the WT and Q2K structures, which allowed us to identify the stability of those amyloid structures. - Highlights: • Lysine mutation effect alters the structure conformation and characteristic of tau. • Over the 15 layers both WT and Q2K models, both tau proteins undergo fractions. • Lysine mutation causes the increment of non-bonded energy and solvent accessible surface area. • Structural instability of Q2K model was proved by the number of hydrogen bonds analysis.

  17. Novel NSAID-Derived Drugs for the Potential Treatment of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Ivana Cacciatore

    2016-06-01

    Full Text Available Nonsteroidal anti-inflammatory drugs (NSAIDs have been suggested for the potential treatment of neurodegenerative diseases, such as Alzheimer’s disease (AD. Prolonged use of NSAIDs, however, produces gastrointestinal (GI toxicity. To overcome this serious limitation, the aim of this study was to develop novel NSAID-derived drug conjugates (Anti-inflammatory-Lipoyl derivatives, AL4–9 that preserve the beneficial effects of NSAIDS without causing GI problems. As such, we conjugated selected well-known NSAIDs, such as (S-naproxen and (R-flurbiprofen, with (R-α-lipoic acid (LA through alkylene diamine linkers. The selection of the antioxidant LA was based on the proposed role of oxidative stress in the development and/or progression of AD. Our exploratory studies revealed that AL7 containing the diaminoethylene linker between (R-flurbiprofen and LA had the most favorable chemical and in vitro enzymatic stability profiles among the synthesized compounds. Upon pretreatment, this compound exhibited excellent antioxidant activity in phorbol 12-miristate 13-acetate (PMA-stimulated U937 cells (lymphoblast lung from human and Aβ(25–35-treated THP-1 cells (leukemic monocytes. Furthermore, AL7 also modulated the expression of COX-2, IL-1β and TNF-α in these cell lines, suggesting anti-inflammatory activity. Taken together, AL7 has emerged as a potential lead worthy of further characterization and testing in suitable in vivo models of AD.

  18. Overexpression of KCNJ2 in induced pluripotent stem cell-derived cardiomyocytes for the assessment of QT-prolonging drugs

    Directory of Open Access Journals (Sweden)

    Min Li

    2017-06-01

    Full Text Available Human induced pluripotent stem cell (hiPSC-derived cardiomyocytes hold great potentials to predict pro-arrhythmic risks in preclinical cardiac safety screening, although the hiPSC cardiomyocytes exhibit rather immature functional and structural characteristics, including spontaneous activity. Our physiological characterization and mathematical simulation showed that low expression of the inward-rectifier potassium (IK1 channel is a determinant of spontaneous activity. To understand impact of the low IK1 expression on the pharmacological properties, we tested if transduction of hiPSC-derived cardiomyocytes with KCNJ2, which encodes the IK1 channel, alters pharmacological response to cardiac repolarization processes. The transduction of KCNJ2 resulted in quiescent hiPSC-derived cardiomyocytes, which need pacing to elicit action potentials. Significant prolongation of paced action potential duration in KCNJ2-transduced hiPSC-derived cardiomyocytes was stably measured at 0.1 μM E-4031, although the same concentration of E-4031 ablated firing of non-treated hiPSC-derived cardiomyocytes. These results in single cells were confirmed by mathematical simulations. Using the hiPSC-derived cardiac sheets with KCNJ2-transduction, we also investigated effects of a range of drugs on field potential duration recorded at 1 Hz. The KCNJ2 overexpression in hiPSC-derived cardiomyocytes may contribute to evaluate a part of QT-prolonging drugs at toxicological concentrations with high accuracy.

  19. Personality, Drug Preference, Drug Use, and Drug Availability

    Science.gov (United States)

    Feldman, Marc; Boyer, Bret; Kumar, V. K.; Prout, Maurice

    2011-01-01

    This study examined the relationship between drug preference, drug use, drug availability, and personality among individuals (n = 100) in treatment for substance abuse in an effort to replicate the results of an earlier study (Feldman, Kumar, Angelini, Pekala, & Porter, 2007) designed to test prediction derived from Eysenck's (1957, 1967)…

  20. Expand classical drug administration ways by emerging routes using dendrimer drug delivery systems: a concise overview.

    Science.gov (United States)

    Mignani, Serge; El Kazzouli, Saïd; Bousmina, Mosto; Majoral, Jean-Pierre

    2013-10-01

    Drugs are introduced into the body by numerous routes such as enteral (oral, sublingual and rectum administration), parenteral (intravascular, intramuscular, subcutaneous and inhalation administration), or topical (skin and mucosal membranes). Each route has specific purposes, advantages and disadvantages. Today, the oral route remains the preferred one for different reasons such as ease and compliance by patients. Several nanoformulated drugs have been already approved by the FDA, such as Abelcet®, Doxil®, Abraxane® or Vivagel®(Starpharma) which is an anionic G4-poly(L-lysine)-type dendrimer showing potent topical vaginal microbicide activity. Numerous biochemical studies, as well as biological and pharmacological applications of both dendrimer based products (dendrimers as therapeutic compounds per se, like Vivagel®) and dendrimers as drug carriers (covalent conjugation or noncovalent encapsulation of drugs) were described. It is widely known that due to their outstanding physical and chemical properties, dendrimers afforded improvement of corresponding carried-drugs as dendrimer-drug complexes or conjugates (versus plain drug) such as biodistribution and pharmacokinetic behaviors. The purpose of this manuscript is to review the recent progresses of dendrimers as nanoscale drug delivery systems for the delivery of drugs using enteral, parenteral and topical routes. In particular, we focus our attention on the emerging and promising routes such as oral, transdermal, ocular and transmucosal routes using dendrimers as delivery systems. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Mechanisms of mono- and poly-ubiquitination: Ubiquitination specificity depends on compatibility between the E2 catalytic core and amino acid residues proximal to the lysine

    Directory of Open Access Journals (Sweden)

    Sadowski Martin

    2010-08-01

    Full Text Available Abstract Ubiquitination involves the attachment of ubiquitin to lysine residues on substrate proteins or itself, which can result in protein monoubiquitination or polyubiquitination. Ubiquitin attachment to different lysine residues can generate diverse substrate-ubiquitin structures, targeting proteins to different fates. The mechanisms of lysine selection are not well understood. Ubiquitination by the largest group of E3 ligases, the RING-family E3 s, is catalyzed through co-operation between the non-catalytic ubiquitin-ligase (E3 and the ubiquitin-conjugating enzyme (E2, where the RING E3 binds the substrate and the E2 catalyzes ubiquitin transfer. Previous studies suggest that ubiquitination sites are selected by E3-mediated positioning of the lysine toward the E2 active site. Ultimately, at a catalytic level, ubiquitination of lysine residues within the substrate or ubiquitin occurs by nucleophilic attack of the lysine residue on the thioester bond linking the E2 catalytic cysteine to ubiquitin. One of the best studied RING E3/E2 complexes is the Skp1/Cul1/F box protein complex, SCFCdc4, and its cognate E2, Cdc34, which target the CDK inhibitor Sic1 for K48-linked polyubiquitination, leading to its proteasomal degradation. Our recent studies of this model system demonstrated that residues surrounding Sic1 lysines or lysine 48 in ubiquitin are critical for ubiquitination. This sequence-dependence is linked to evolutionarily conserved key residues in the catalytic region of Cdc34 and can determine if Sic1 is mono- or poly-ubiquitinated. Our studies indicate that amino acid determinants in the Cdc34 catalytic region and their compatibility to those surrounding acceptor lysine residues play important roles in lysine selection. This may represent a general mechanism in directing the mode of ubiquitination in E2 s.

  2. Effect of low protein diets and lysine supplementation on growth ...

    African Journals Online (AJOL)

    The present study was to assess the effect of feeding low protein diet with or without supplemental lysine to meet NRC (1998) requirement on growth performance, carcass trait, meat composition, and meat quality of pigs. An experiment of 126 days was conducted on 21 crossbred Landrace pigs (average weight 11.72 ...

  3. New insights into the interplay between the lysine transporter LysP and the pH sensor CadC in Escherichia coli.

    Science.gov (United States)

    Rauschmeier, Martina; Schüppel, Valentina; Tetsch, Larissa; Jung, Kirsten

    2014-01-09

    The coordination of signal transduction and substrate transport represents a sophisticated way to integrate information on metabolite fluxes into transcriptional regulation. This widely distributed process involves protein-protein interactions between two integral membrane proteins. Here we report new insights into the molecular mechanism of the regulatory interplay between the lysine-specific permease LysP and the membrane-integrated pH sensor CadC, which together induce lysine-dependent adaptation of E. coli under acidic stress. In vivo analyses revealed that, in the absence of either stimulus, the two proteins form a stable association, which is modulated by lysine and low pH. In addition to its transmembrane helix, the periplasmic domain of CadC also participated in the interaction. Site-directed mutagenesis pinpointed Arg265 and Arg268 in CadC as well as Asp275 and Asp278 in LysP as potential periplasmic interaction sites. Moreover, a systematic analysis of 100 LysP variants with single-site replacements indicated that the lysine signal is transduced from co-sensor to sensor via lysine-dependent conformational changes (upon substrate binding and/or transport) of LysP. Our results suggest a scenario in which CadC is inhibited by LysP via intramembrane and periplasmic contacts under non-inducing conditions. Upon induction, lysine-dependent conformational changes in LysP transduce the lysine signal via a direct conformational coupling to CadC without resolving the interaction completely. Moreover, concomitant pH-dependent protonation of periplasmic amino acids in both proteins dissolves their electrostatic connections resulting in further destabilization of the CadC/LysP interaction. © 2013.

  4. Tumor accumulation of {epsilon}-poly-lysines-based polyamines conjugated with boron clusters

    Energy Technology Data Exchange (ETDEWEB)

    Umano, Masayuki; Uechi, Kazuhiro; Uriuda, Takatoshi; Murayama, Sayuri; Azuma, Hideki [Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 5588585 (Japan); Shinohara, Atsuko [Department of Epidemiology and Environmental Health, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 1138421 (Japan); Liu, Young; Ono, Koji [Research Reactor Institute, Kyoto University, 2-1010 Asashiro-nishi, Kumatori 5900494 (Japan); Kirihata, Mitsunori [Department of Bioscience and Informatics, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai 5998531 (Japan); Yanagie, Hironobu [Department of Nuclear Engineering and Management, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 1138656 (Japan); Nagasaki, Takeshi, E-mail: nagasaki@bioa.eng.osaka-cu.ac.jp [Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 5588585 (Japan)

    2011-12-15

    Boron Neutron Capture Therapy (BNCT) is one of the potent cancer radiotherapies using nuclear reaction between {sup 10}B atoms and the neutron. Whether BNCT will succeed or not depends on tumor selective delivery of {sup 10}B compounds. {epsilon}-Poly-L-lysine is a naturally occurring polyamine characterized by the peptide linkages between the carboxyl and {epsilon}-amino groups of L-lysine. Because of high safety {epsilon}-PLL is applied practically as a food additive due to its strong antimicrobial activity. In this study, we focus on a development of a novel polymeric delivery system for BNCT using biodegradable {epsilon}-PLL conjugated with {sup 10}B-containing clusters (BSH). This polymeric boron carrier will be expected to deliver safely and efficiently into tumor tissues based on Enhanced Permeability and Retention (EPR) effect.

  5. Tranexamic acid-associated seizures: Causes and treatment.

    Science.gov (United States)

    Lecker, Irene; Wang, Dian-Shi; Whissell, Paul D; Avramescu, Sinziana; Mazer, C David; Orser, Beverley A

    2016-01-01

    Antifibrinolytic drugs are routinely used worldwide to reduce the bleeding that results from a wide range of hemorrhagic conditions. The most commonly used antifibrinolytic drug, tranexamic acid, is associated with an increased incidence of postoperative seizures. The reported increase in the frequency of seizures is alarming, as these events are associated with adverse neurological outcomes, longer hospital stays, and increased in-hospital mortality. However, many clinicians are unaware that tranexamic acid causes seizures. The goal of this review is to summarize the incidence, risk factors, and clinical features of these seizures. This review also highlights several clinical and preclinical studies that offer mechanistic insights into the potential causes of and treatments for tranexamic acid-associated seizures. This review will aid the medical community by increasing awareness about tranexamic acid-associated seizures and by translating scientific findings into therapeutic interventions for patients. © 2015 The Authors Annals of Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.

  6. Design and Application of Synthetic Receptors for Recognition of Methylated Lysine and Supramolecular Affinity Labeling

    Science.gov (United States)

    Gober, Isaiah Nathaniel

    This dissertation involves the design and synthesis of new synthetic receptors and their application in the molecular recognition of methylated lysine and their use as tools for chemical biology. The dissertation is divided into four parts. The first section focuses on the development of a novel labeling method that is based on ligand-directed affinity labeling principles. In this labeling method, a synthetic receptor that binds to trimethyl lysine (Kme3) is attached through a linker to an electrophilic tag group that can react with a nucleophilic amine in a histone peptide. This affinity labeling probe, which we called CX4-ONBD, is equipped with an electrophilic tag that allows for turn-on fluorescence labeling of Kme3 histone peitdes. We show that the probe gives a pronounced turn-on fluorescence response when it is incubated with a histone peptide that contains Kme3 and a nearby reactive lysine. This probe also displays >5-fold selectivity in covalent labeling over an unmethylated lysine peptide. This represents the first time a synthetic receptor has been used for affinity labeling purposes, and it also expands on the chemical toolkit that is available for sensing PTMs like lysine methylation. In the second section, the supramolecular affinity labeling method that was optimized using CX4-ONBD was applied to the development of a real-time assay for measuring enzymatic activity. More specifically, the probe was used to create a turn-on fluorescence assay for histone deacetylase (HDAC) activity and for inhibitor screening and IC50 determination. Most commercial kits for HDAC activity have limited substrate scope, and other common methods used for characterizing enzymatic activity often require chromatographic separation and are therefore not high-throughput. This small molecule receptor-mediated affinity labeling strategy allowed for facile readout of HDAC activity and inhibition. Overall, this application of supramolecular affinity labeling expands on the

  7. Synthesis of L-lysine imprinted cryogels for immunoglobulin G adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Çulha, Senem; Armutcu, Canan; Uzun, Lokman; Şenel, Serap, E-mail: senel@hacettepe.edu.tr; Denizli, Adil

    2015-07-01

    L-Lysine imprinted poly(2-hydroxyethyl methacrylate-co-N-methacryloyl-L-aspartic acid) [P(HEMA-co-MAAsp)] cryogels were synthesized and characterized with Fourier transform infrared spectroscopy, scanning electron microscopy, surface area measurements, swelling, and squeezing tests. Specific surface area for imprinted cryogel was 34.2 m{sup 2}/g while the value was 21.3 m{sup 2}/g for non-imprinted cryogel. IgG adsorption from aqueous solution was examined in continuous mode examining the factors effecting adsorption capacity such as pH, concentration, flow rate, temperature, ionic strength, and incubation time. 0.5 M NaCl was used as desorption agent. The IgG adsorption capacity was determined as 55.1 mg/g for 1.0 mg/mL IgG original concentration at 25.0 °C while pH and flow rate were 7.0 and 0.5 mL/min, respectively. When human serum was used as IgG source, the removal of 90.4% of crude IgG was attained for 1/20 diluted plasma sample. The imprinted cryogel was used in ten successive cycles without significant loss in adsorption capacity. The cryogel was determined to be 1.79 times more selective to IgG than albumin and 1.45 times more selective than hemoglobin. The adsorption behavior well suited to Langmuir isotherm and the kinetics followed pseudo-second-order model. Thermodynamic parameters ΔH°, ΔS° and ΔG° for this adsorption process were also calculated. - Highlights: • L-Lysine imprinted cryogels through epitope imprinting approach • Optimization of recognition conditions for template (L-lysine) and target (IgG) biomolecules • Efficient reusability (upto 10 cycles) without any significant change in capacity • A great potential for specific and selective IgG purification • Promising, cost-friendly, specific and selective adsorbent • IgG separation/purification from complex feeding solutions like human serum.

  8. Assessing the drug-likeness of lamellarins, a marine-derived natural product class with diverse oncological activities.

    Science.gov (United States)

    Chittchang, Montakarn; Gleeson, M Paul; Ploypradith, Poonsakdi; Ruchirawat, Somsak

    2010-06-01

    Natural products currently represent an underutilized source of leads for the pharmaceutical industry, especially when one considers that almost 50% of all drugs were either derived from such sources or are very closely related. Lamellarins are a class of natural products with diverse biological activities and have entered into preclinical development for the treatment of multidrug-resistant tumors. Although these compounds demonstrated good cell penetration, as observed by their low microM activity in whole cell models, they have not been extensively profiled from a physicochemical point of view, and this is the goal of this study. For this study, we have determined the experimental logP values of a set of 25 lamellarins, given it is the single most important parameter in determining multiple ADMET parameters. We also discuss the relationship between this natural product class, natural product derivatives in development and on the market, oral marketed drugs, as well as drug molecules in development, using a range of physicochemical parameters in conjunction with principal components analysis (PCA). The impact of this systematic analysis on our ongoing medicinal chemistry strategy is also discussed. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

  9. Comparative pharmacokinetics of cefuroxime lysine after single intravenous, intraperitoneal, and intramuscular administration to rats.

    Science.gov (United States)

    Zhao, Long-shan; Yin, Ran; Wei, Bin-bin; Li, Qing; Jiang, Zhen-yuan; Chen, Xiao-hui; Bi, Kai-shun

    2012-11-01

    To compare the pharmacokinetic parameters of cefuroxime lysine, a new second-generation of cephalosporin antibiotics, after intravenous (IV), intraperitoneal (IP), or intramuscular (IM) administration. Twelve male and 12 virgin female Sprague-Dawley rats, weighing from 200 to 250 g, were divided into three groups (n=4 for each gender in each group). The rats were administered a single dose (67.5 mg/kg) of cefuroxime lysine via IV bolus or IP or IM injection. Blood samples were collected and analyzed with a validated UFLC-MS/MS method. The concentration-time data were then calculated by compartmental and non-compartmental pharmacokinetic methods using DAS software. After IV, IP or IM administration, the plasma cefuroxime lysine disposition was best described by a tri-compartmental, bi-compartmental or mono-compartmental open model, respectively, with first-order elimination. The plasma concentration profiles were similar through the 3 administration routes. The distribution process was rapid after IV administration [t(1/2(d)), 0.10 ± 0.11 h vs 1.36 ± 0.65 and 1.25 ± 1.01 h]. The AUMC(0-∞) is markedly larger, and mean residence time (MRT) is greatly longer after IP administration than that in IV, or IM routes (AUMC(0-∞): 55.33 ± 20.34 vs 16.84 ± 4.85 and 36.17 ± 13.24 mg·h(2)/L; MRT: 0.93 ± 0.10 h vs 0.37 ± 0.07 h and 0.65 ± 0.05 h). The C(max) after IM injection was significantly higher than that in IP injection (73.51 ± 12.46 vs 49.09 ± 7.06 mg/L). The AUC(0-∞) in male rats were significantly higher than that in female rats after IM administration (66.38 ± 16.5 vs 44.23 ± 6.37 mg·h/L). There was no significantly sex-related difference in other pharmacokinetic parameters of cefuroxime lysine between male and female rats. Cefuroxime lysine shows quick absorption after IV injection, a long retension after IP injection, and a high C(max) after IM injection. After IM administration the AUC(0-∞) in male rats was significantly larger than that in

  10. Elicitin-induced distal systemic resistance in plants is mediated through the protein-protein interactions influenced by selected lysine residues

    Directory of Open Access Journals (Sweden)

    Hana eUhlíková

    2016-02-01

    Full Text Available Elicitins are a family of small proteins with sterol-binding activity that are secreted by Phytophthora and Pythium spp. classified as oomycete PAMPs. Although alfa- and beta-elicitins bind with the same affinity to one high affinity binding site on the plasma membrane, beta-elicitins (possessing 6-7 lysine residues are generally 50- to 100-fold more active at inducing distal HR and systemic resistance than the alfa-isoforms (with only 1-3 lysine residues.To examine the role of lysine residues in elicitin biological activity, we employed site-directed mutagenesis to prepare a series of beta-elicitin cryptogein variants with mutations on specific lysine residues. In contrast to direct infiltration of protein into leaves, application to the stem revealed a rough correlation between protein’s charge and biological activity, resulting in protection against Phytophthora parasitica. A detailed analysis of proteins’ movement in plants showed no substantial differences in distribution through phloem indicating differences in consequent apoplastic or symplastic transport. In this process, an important role of homodimer formation together with the ability to form a heterodimer with potential partner represented by endogenous plants LTPs is suggested. Our work demonstrates a key role of selected lysine residues in these interactions and stresses the importance of processes preceding elicitin recognition responsible for induction of distal systemic resistance.

  11. Lysine-Directed Post-translational Modifications of Tau Protein in Alzheimer's Disease and Related Tauopathies

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    Christiana Kontaxi

    2017-08-01

    Full Text Available Tau is a microtubule-associated protein responsible mainly for stabilizing the neuronal microtubule network in the brain. Under normal conditions, tau is highly soluble and adopts an “unfolded” conformation. However, it undergoes conformational changes resulting in a less soluble form with weakened microtubule stabilizing properties. Altered tau forms characteristic pathogenic inclusions in Alzheimer's disease and related tauopathies. Although, tau hyperphosphorylation is widely considered to be the major trigger of tau malfunction, tau undergoes several post-translational modifications at lysine residues including acetylation, methylation, ubiquitylation, SUMOylation, and glycation. We are only beginning to define the site-specific impact of each type of lysine modification on tau biology as well as the possible interplay between them, but, like phosphorylation, these modifications are likely to play critical roles in tau's normal and pathobiology. This review summarizes the latest findings focusing on lysine post-translational modifications that occur at both endogenous tau protein and pathological tau forms in AD and other tauopathies. In addition, it highlights the significance of a site-dependent approach of studying tau post-translational modifications under normal and pathological conditions.

  12. The structure, vibrational spectra and nonlinear optical properties of the L-lysine × tartaric acid complex—Theoretical studies

    Science.gov (United States)

    Drozd, M.; Marchewka, M. K.

    2006-05-01

    The room temperature X-ray studies of L-lysine × tartaric acid complex are not unambiguous. The disorder of three atoms of carbon in L-lysine molecule is observed. These X-ray studies are ambiguous. The theoretical geometry study performed by DFT methods explain the most doubts which are connected with crystallographic measurements. The theoretical vibrational frequencies and potential energy distribution (PED) of L-lysine × tartaric acid were calculated by B3LYP method. The calculated frequencies were compared with experimental measured IR spectra. The complete assignment of the bands has been made on the basis of the calculated PED. The restricted Hartee-Fock (RHF) methods were used for calculation of the hyperpolarizability for investigated compound. The theoretical results are compared with experimental value of β.

  13. Effect Of Sprouting On Available Lysine Content Of Cowpea ( Vigna ...

    African Journals Online (AJOL)

    This study was conducted to determine the effect of sprouting on available Lysine content of cowpea (Vigna unguiculata) flour and the performance of the flour used for producing “moi – moi” (steamed bean cake). Cowpea seed was subjected to sprouting for different periods of 1 day, 2 days and 3 days for samples B, C and ...

  14. PSG gene expression is up-regulated by lysine acetylation involving histone and nonhistone proteins.

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    Soledad A Camolotto

    Full Text Available BACKGROUND: Lysine acetylation is an important post-translational modification that plays a central role in eukaryotic transcriptional activation by modifying chromatin and transcription-related factors. Human pregnancy-specific glycoproteins (PSG are the major secreted placental proteins expressed by the syncytiotrophoblast at the end of pregnancy and represent early markers of cytotrophoblast differentiation. Low PSG levels are associated with complicated pregnancies, thus highlighting the importance of studying the mechanisms that control their expression. Despite several transcription factors having been implicated as key regulators of PSG gene family expression; the role of protein acetylation has not been explored. METHODOLOGY/PRINCIPAL FINDINGS: Here, we explored the role of acetylation on PSG gene expression in the human placental-derived JEG-3 cell line. Pharmacological inhibition of histone deacetylases (HDACs up-regulated PSG protein and mRNA expression levels, and augmented the amount of acetylated histone H3 associated with PSG 5'regulatory regions. Moreover, PSG5 promoter activation mediated by Sp1 and KLF6, via the core promoter element motif (CPE, -147/-140, was markedly enhanced in the presence of the HDAC inhibitor trichostatin A (TSA. This effect correlated with an increase in Sp1 acetylation and KLF6 nuclear localization as revealed by immunoprecipitation and subcellular fractionation assays. The co-activators PCAF, p300, and CBP enhanced Sp1-dependent PSG5 promoter activation through their histone acetylase (HAT function. Instead, p300 and CBP acetyltransferase domain was dispensable for sustaining co-activation of PSG5 promoter by KLF6. CONCLUSIONS/SIGNIFICANCE: Results are consistent with a regulatory role of lysine acetylation on PSG expression through a relaxed chromatin state and an increase in the transcriptional activity of Sp1 and KLF6 following an augmented Sp1 acetylation and KLF6 nuclear localization.

  15. De Novo Assembly and Comparative Transcriptome Analysis Provide Insight into Lysine Biosynthesis in Toona sinensis Roem.

    Science.gov (United States)

    Zhang, Xia; Song, Zhenqiao; Liu, Tian; Guo, Linlin; Li, Xingfeng

    2016-01-01

    Toona sinensis Roem is a popular leafy vegetable in Chinese cuisine and is also used as a traditional Chinese medicine. In this study, leaf samples were collected from the same plant on two development stages and then used for high-throughput Illumina RNA-sequencing (RNA-Seq). 125,884 transcripts and 54,628 unigenes were obtained through de novo assembly. A total of 25,570 could be annotated with known biological functions, which indicated that the T. sinensis leaves and shoots were undergoing multiple developmental processes especially for active metabolic processes. Analysis of differentially expressed unigenes between the two libraries showed that the lysine biosynthesis was an enriched KEGG pathway, and candidate genes involved in the lysine biosynthesis pathway in T. sinensis leaves and shoots were identified. Our results provide a primary analysis of the gene expression files of T. sinensis leaf and shoot on different development stages and afford a valuable resource for genetic and genomic research on plant lysine biosynthesis.

  16. Drug susceptibility to etravirine and darunavir among Human Immunodeficiency Virus Type 1-derived pseudoviruses in treatment-experienced patients with HIV/AIDS in South Korea.

    Science.gov (United States)

    Kwon, Oh-Kyung; Kim, Sung Soon; Rhee, Jee Eun; Kee, Mee-Kyung; Park, Mina; Oh, Hye-Ri; Choi, Ju-Yeon

    2015-04-09

    In South Korea, about 20 types of antiretroviral drugs are used in the treatment of patients with human immunodeficiency virus/acquired immune deficiency syndrome. Since 2010, raltegravir, etravirine, and darunavir have been spotlighted as new drugs for highly active antiretroviral therapy (HAART)-experienced adults with resistant HIV-1 in South Korea. In this study, we investigated potential susceptibility of pseudoviruses derived from treatment-experienced Korean patients to etravirine vs efavirenz and to darunavir vs amprenavir and indinavir using a modified single-round assay. Pseudoviruses derived from nine treatment-experienced patients infected with HIV-1 were investigated by comparison with the wild-type strain pNL4-3. The 50% inhibitory concentration (IC50) values were calculated and drug susceptibility was compared. The intensity of genotypic drug resistance was classified based on the 'SIR' interpretation of the Stanford data base. Drug susceptibility was generally higher for etravirine and darunavir compared with efavirenz, amprenavir, and indinavir in pseudoviruses derived from treatment-experienced patients. Pseudoviruses derived from patients KRB4025 and KRB8014, who exhibited long-term use of protease inhibitors, showed an outside of tested drug concentration, especially for amprenavir and indinavir. However, they exhibited a lower fold-change in resistance to darunavir. Etravirine and darunavir have been used in HAART since 2010 in South Korea. Therefore, these antiretroviral drugs together with other newly introduced antiretroviral drugs are interesting for the optimal treatment of patients with treatment failure. This study may help to find a more effective HAART in the case of HIV-1 infected patients that have difficulty being treated.

  17. Dystrophin-deficient cardiomyocytes derived from human urine: New biologic reagents for drug discovery

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    Xuan Guan

    2014-03-01

    Full Text Available The ability to extract somatic cells from a patient and reprogram them to pluripotency opens up new possibilities for personalized medicine. Induced pluripotent stem cells (iPSCs have been employed to generate beating cardiomyocytes from a patient's skin or blood cells. Here, iPSC methods were used to generate cardiomyocytes starting from the urine of a patient with Duchenne muscular dystrophy (DMD. Urine was chosen as a starting material because it contains adult stem cells called urine-derived stem cells (USCs. USCs express the canonical reprogramming factors c-myc and klf4, and possess high telomerase activity. Pluripotency of urine-derived iPSC clones was confirmed by immunocytochemistry, RT-PCR and teratoma formation. Urine-derived iPSC clones generated from healthy volunteers and a DMD patient were differentiated into beating cardiomyocytes using a series of small molecules in monolayer culture. Results indicate that cardiomyocytes retain the DMD patient's dystrophin mutation. Physiological assays suggest that dystrophin-deficient cardiomyocytes possess phenotypic differences from normal cardiomyocytes. These results demonstrate the feasibility of generating cardiomyocytes from a urine sample and that urine-derived cardiomyocytes retain characteristic features that might be further exploited for mechanistic studies and drug discovery.

  18. Reducing Renal Uptake of {sup 177}Lu Labeled CCK Derivative using Basic Amino Acids

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Soyoung; Lim, Jaecheong; Joh, Eunha [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    Radiolabeled peptides have been designed to target the relative receptors overespressed in tumor cells, such as integrin αvβ3, gastrin-releasing peptide receptor (GRPR), melanocortin-1 receptor (MC1-R), glucagon-like peptide-a receptor (GLP-1R), and cholecystokinin (CCK) receptor. Most of these peptides are eliminated from the body via the kidney and are partly reabsorbed in the proximal tubular cells. However, the high renal uptake of the radiolabeled peptides may lead to renal toxicity. In this study we investigated various amino acid solutions to reduce the renal uptake of {sup 177}Lu-DOTA-CCK derivative. Renal uptake of {sup 177}Lu-DOTA-CCK derivative is effectively reduced by the administration of positively charged amino acids. The administration of 12 mg of L-lysine was as effective in reducing the renal uptake as 6 mg of lysine and 6 mg of arginine combinations. Further studies will be performed to identify the most potent inhibitor of renal reuptake of radiolabeled peptides and minimize the chance of unwanted side effects.

  19. Quantification of nitrogen in the liquid fraction and in vitro assessment of lysine bioavailability in the solid fraction of soybean meal hydrolysates.

    Science.gov (United States)

    Luján-Rhenals, D; Morawicki, R; Shi, Z; Ricke, S C

    2018-01-02

    Soybean meal (SBM) is a product generated from the manufacture of soybean oil and has the potential for use as a source of fermentable sugars for ethanol production or as a protein source for animal feeds. Knowing the levels of nitrogen available from ammonium is a necessary element of the ethanolic fermentation process while identifying the levels of essential amino acids such as lysine is important in determining usage as a feed source. As such the purpose of this study was to quantify total nitrogen and ammonium in the liquid fraction of hydrolyzed SBM and to evaluate total and bioavailable lysine in the solid fraction of the hydrolyzed SBM. The effects of acid concentration, cellulase and β-glucosidase on total and ammonium nitrogen were studied with analysis indicating that higher acid concentrations increased nitrogen compounds with ammonium concentrations ranging from 0.20 to 1.24 g L -1 while enzymatic treatments did not significantly increase nitrogen levels. Total and bioavailable lysine was quantified by use of an auxotrophic gfpmut3 E.coli whole-cell bioassay organism incapable of lysine biosynthesis. Acid and enzymatic treatments were applied with lysine bioavailability increasing from a base of 82% for untreated SBM to up to 97%. Our results demonstrated that SBM has the potential to serve in ethanolic fermentation and as an optimal source essential amino acid lysine.

  20. Duplicate Abalone Egg Coat Proteins Bind Sperm Lysin Similarly, but Evolve Oppositely, Consistent with Molecular Mimicry at Fertilization

    Science.gov (United States)

    Aagaard, Jan E.; Springer, Stevan A.; Soelberg, Scott D.; Swanson, Willie J.

    2013-01-01

    Sperm and egg proteins constitute a remarkable paradigm in evolutionary biology: despite their fundamental role in mediating fertilization (suggesting stasis), some of these molecules are among the most rapidly evolving ones known, and their divergence can lead to reproductive isolation. Because of strong selection to maintain function among interbreeding individuals, interacting fertilization proteins should also exhibit a strong signal of correlated divergence among closely related species. We use evidence of such molecular co-evolution to target biochemical studies of fertilization in North Pacific abalone (Haliotis spp.), a model system of reproductive protein evolution. We test the evolutionary rates (d N/d S) of abalone sperm lysin and two duplicated egg coat proteins (VERL and VEZP14), and find a signal of co-evolution specific to ZP-N, a putative sperm binding motif previously identified by homology modeling. Positively selected residues in VERL and VEZP14 occur on the same face of the structural model, suggesting a common mode of interaction with sperm lysin. We test this computational prediction biochemically, confirming that the ZP-N motif is sufficient to bind lysin and that the affinities of VERL and VEZP14 are comparable. However, we also find that on phylogenetic lineages where lysin and VERL evolve rapidly, VEZP14 evolves slowly, and vice versa. We describe a model of sexual conflict that can recreate this pattern of anti-correlated evolution by assuming that VEZP14 acts as a VERL mimic, reducing the intensity of sexual conflict and slowing the co-evolution of lysin and VERL. PMID:23408913

  1. Duplicate abalone egg coat proteins bind sperm lysin similarly, but evolve oppositely, consistent with molecular mimicry at fertilization.

    Directory of Open Access Journals (Sweden)

    Jan E Aagaard

    Full Text Available Sperm and egg proteins constitute a remarkable paradigm in evolutionary biology: despite their fundamental role in mediating fertilization (suggesting stasis, some of these molecules are among the most rapidly evolving ones known, and their divergence can lead to reproductive isolation. Because of strong selection to maintain function among interbreeding individuals, interacting fertilization proteins should also exhibit a strong signal of correlated divergence among closely related species. We use evidence of such molecular co-evolution to target biochemical studies of fertilization in North Pacific abalone (Haliotis spp., a model system of reproductive protein evolution. We test the evolutionary rates (d(N/d(S of abalone sperm lysin and two duplicated egg coat proteins (VERL and VEZP14, and find a signal of co-evolution specific to ZP-N, a putative sperm binding motif previously identified by homology modeling. Positively selected residues in VERL and VEZP14 occur on the same face of the structural model, suggesting a common mode of interaction with sperm lysin. We test this computational prediction biochemically, confirming that the ZP-N motif is sufficient to bind lysin and that the affinities of VERL and VEZP14 are comparable. However, we also find that on phylogenetic lineages where lysin and VERL evolve rapidly, VEZP14 evolves slowly, and vice versa. We describe a model of sexual conflict that can recreate this pattern of anti-correlated evolution by assuming that VEZP14 acts as a VERL mimic, reducing the intensity of sexual conflict and slowing the co-evolution of lysin and VERL.

  2. The use of crude protein content to predict concentrations of lysine ...

    African Journals Online (AJOL)

    Correlations were determined between the crude protein (CP) and lysine or methionine concentrations of grain from wheat (cultivar: palmiet), barley (cultivar: clipper) and triticale (cultivar: usgen 19) grown in the Western Cape region of South Africa. Twenty samples of varying CP content were collected for each grain type ...

  3. Lysine acetylation in sexual stage malaria parasites is a target for antimalarial small molecules.

    Science.gov (United States)

    Trenholme, Katharine; Marek, Linda; Duffy, Sandra; Pradel, Gabriele; Fisher, Gillian; Hansen, Finn K; Skinner-Adams, Tina S; Butterworth, Alice; Ngwa, Che Julius; Moecking, Jonas; Goodman, Christopher D; McFadden, Geoffrey I; Sumanadasa, Subathdrage D M; Fairlie, David P; Avery, Vicky M; Kurz, Thomas; Andrews, Katherine T

    2014-07-01

    Therapies to prevent transmission of malaria parasites to the mosquito vector are a vital part of the global malaria elimination agenda. Primaquine is currently the only drug with such activity; however, its use is limited by side effects. The development of transmission-blocking strategies requires an understanding of sexual stage malaria parasite (gametocyte) biology and the identification of new drug leads. Lysine acetylation is an important posttranslational modification involved in regulating eukaryotic gene expression and other essential processes. Interfering with this process with histone deacetylase (HDAC) inhibitors is a validated strategy for cancer and other diseases, including asexual stage malaria parasites. Here we confirm the expression of at least one HDAC protein in Plasmodium falciparum gametocytes and show that histone and nonhistone protein acetylation occurs in this life cycle stage. The activity of the canonical HDAC inhibitors trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA; Vorinostat) and a panel of novel HDAC inhibitors on early/late-stage gametocytes and on gamete formation was examined. Several compounds displayed early/late-stage gametocytocidal activity, with TSA being the most potent (50% inhibitory concentration, 70 to 90 nM). In contrast, no inhibitory activity was observed in P. falciparum gametocyte exflagellation experiments. Gametocytocidal HDAC inhibitors caused hyperacetylation of gametocyte histones, consistent with a mode of action targeting HDAC activity. Our data identify HDAC inhibitors as being among a limited number of compounds that target both asexual and sexual stage malaria parasites, making them a potential new starting point for gametocytocidal drug leads and valuable tools for dissecting gametocyte biology. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  4. Lysine Restriction and Pyridoxal Phosphate Administration in a NADK2 Patient.

    Science.gov (United States)

    Tort, Frederic; Ugarteburu, Olatz; Torres, Maria Angeles; García-Villoria, Judit; Girós, Marisa; Ruiz, Angeles; Ribes, Antonia

    2016-11-01

    We report the case of a 10-year-old Spanish girl with mutations in NADK2 Prenatal central nervous system abnormalities showed ventriculomegaly, colpocephaly, and hypoplasia of the corpus callosum. At birth, axial hypotonia, uncoordinated movements, microcephaly, and generalized cerebellar atrophy were detected. Metabolic investigations revealed high lysine, lactate, and pipecolic acid levels in blood and cerebrospinal fluid. Pyruvate carboxylase and pyruvate dehydrogenase activity in fibroblasts were normal. Beginning at birth she received biotin, thiamine, and carnitine supplementation. A lysine-restricted diet was started when she was 1 month old. Because pipecolic acid was high, pyridoxine was added to treatment. At 3 years old, astatic myoclonic epilepsy appeared, with no response to levetiracetam. We switched pyridoxine to pyridoxal phosphate, with electroclinical improvement. Because the activity of mitochondrial respiratory chain complexes III and IV was slightly low in muscle, other cofactors such as ubidecarenone, idebenone, vitamin E, and creatine were added to the treatment. At 8 years old, plasma acylcarnitine testing was performed, and high levels of 2-trans, 4-cis-decadienoylcarnitine were found. Whole exome sequencing identified a homozygous splice site mutation in NADK2 (c.956+6T>C; p.Trp319Cysfs*21). This substitution generates exon skipping, leading to a truncated protein. In fact, NADK2 messenger RNA and the corresponding protein were almost absent. Now, at 10 years of age she presents with ataxia and incoordination. She has oromotor dysphasia but is able to understand fluid language and is a very friendly girl. We hypothesize that the patient's clinical improvement could be due to her lysine-restricted diet together with cofactors and pyridoxal phosphate administration. Copyright © 2016 by the American Academy of Pediatrics.

  5. How modification of accessible lysines to phenylalanine modulates the structural and functional properties of horseradish peroxidase: a simulation study.

    Directory of Open Access Journals (Sweden)

    Leila Navapour

    Full Text Available Horseradish Peroxidase (HRP is one of the most studied peroxidases and a great number of chemical modifications and genetic manipulations have been carried out on its surface accessible residues to improve its stability and catalytic efficiency necessary for biotechnological applications. Most of the stabilized derivatives of HRP reported to date have involved chemical or genetic modifications of three surface-exposed lysines (K174, K232 and K241. In this computational study, we altered these lysines to phenylalanine residues to model those chemical modifications or genetic manipulations in which these positively charged lysines are converted to aromatic hydrophobic residues. Simulation results implied that upon these substitutions, the protein structure becomes less flexible. Stability gains are likely to be achieved due to the increased number of stable hydrogen bonds, improved heme-protein interactions and more integrated proximal Ca2+ binding pocket. We also found a new persistent hydrogen bond between the protein moiety (F174 and the heme prosthetic group as well as two stitching hydrogen bonds between the connecting loops GH and F'F″ in mutated HRP. However, detailed analysis of functionally related structural properties and dynamical features suggests reduced reactivity of the enzyme toward its substrates. Molecular dynamics simulations showed that substitutions narrow the bottle neck entry of peroxide substrate access channel and reduce the surface accessibility of the distal histidine (H42 and heme prosthetic group to the peroxide and aromatic substrates, respectively. Results also demonstrated that the area and volume of the aromatic-substrate binding pocket are significantly decreased upon modifications. Moreover, the hydrophobic patch functioning as a binding site or trap for reducing aromatic substrates is shrunk in mutated enzyme. Together, the results of this simulation study could provide possible structural clues to explain

  6. Reduced Histone H3 Lysine 9 Methylation Contributes to the Pathogenesis of Latent Autoimmune Diabetes in Adults via Regulation of SUV39H2 and KDM4C

    Directory of Open Access Journals (Sweden)

    Xi-yu Liu

    2017-01-01

    Full Text Available Aims. Latent autoimmune diabetes in adults (LADA is an autoimmune disease of which the mechanism is not clear. Emerging evidence suggests that histone methylation contributes to autoimmunity. Methods. Blood CD4+ T lymphocytes from 26 LADA patients and 26 healthy controls were isolated to detect histone H3 lysine 4 and H3 lysine 9 methylation status. Results. Reduced global H3 lysine 9 methylation was observed in LADA patients’ CD4+ T lymphocytes, compared to healthy controls (P < 0.05. H3 lysine 4 methylation was not statistically different. The reduced H3 lysine 9 methylation was associated with GADA titer but not correlated with glycosylated hemoglobin (HbA1c. When the LADA patient group was divided into those with complication and those without, relatively reduced global H3 lysine 9 methylation was observed in LADA patients with complication (P < 0.05. The expression of histone methyltransferase SUV39H2 for H3 lysine 9 methylation was downregulated in LADA patients, and the expression of histone demethylase KDM4C which made H3 lysine 9 demethylation was upregulated. Conclusion. The reduction of histone H3 lysine 9 methylation which may due to the downregulation of methyltransferase SUV39H2 and the upregulation of demethylase KDM4C was found in CD4+ T lymphocytes of LADA patients.

  7. Tyrosine-derived polycarbonate-silica xerogel nanocomposites for controlled drug delivery.

    Science.gov (United States)

    Costache, M C; Vaughan, A D; Qu, H; Ducheyne, P; Devore, D I

    2013-05-01

    Biodegradable polymer-ceramic composites offer significant potential advantages in biomedical applications where the properties of either polymers or ceramics alone are insufficient to meet performance requirements. Here we demonstrate the highly tunable mechanical and controlled drug delivery properties accessible with novel biodegradable nanocomposites prepared by non-covalent binding of silica xerogels and co-polymers of tyrosine-poly(ethylene glycol)-derived poly(ether carbonate). The Young's moduli of the nanocomposites exceed by factors of 5-20 times those of the co-polymers or of composites made with micron scale silica particles. Increasing the fraction of xerogel in the nanocomposites increases the glass transition temperature and the mechanical strength, but decreases the equilibrium water content, which are all indicative of strong non-covalent interfacial interactions between the co-polymers and the silica nanoparticles. Sustained, tunable controlled release of both hydrophilic and hydrophobic therapeutic agents from the nanocomposites is demonstrated with two clinically significant drugs, rifampicin and bupivacaine. Bupivacaine exhibits an initial small burst release followed by slow release over the 7 day test period. Rifampicin release fits the diffusion-controlled Higuchi model and the amount released exceeds the dosage required for treatment of clinically challenging infections. These nanocomposites are thus attractive biomaterials for applications such as wound dressings, tissue engineering substrates and stents. Published by Elsevier Ltd.

  8. Formation of lysine-derived oxidation products and loss of tryptophan during processing of porcine patties with added avocado byproducts.

    Science.gov (United States)

    Utrera, Mariana; Rodríguez-Carpena, Javier-Germán; Morcuende, David; Estévez, Mario

    2012-04-18

    The effects of the addition of avocado oil and a phenolic-rich avocado peel extract on protein oxidation were studied in porcine patties subjected to cooking and chilled storage. Protein oxidation was assessed by means of tryptophan loss and the formation of specific lysine oxidation products, such as α-aminoadipic semialdehyde (AAS), α-aminoadipic acid (AAA), and Schiff bases. In the present paper, quantitative data of AAA are reported for the first time on a food matrix. The addition of the avocado extract inhibited the formation of AAS, AAA, and Schiff bases in patties during cooking and subsequent chilled storage. The antioxidant effect may respond to the protecting effect of phenolic compounds, mainly procyanidins, found on the avocado extract. Apparently, the combination of both strategies (back-fat replacement and addition of avocado extract) does not lead to an enhanced advantage on the oxidative stability of the product. The novel methodologies used in the present study enable a better comprehension of the mechanisms and consequences of protein oxidation in food systems.

  9. Lysine-Derived Protein-Bound Heyns Compounds in Bakery Products.

    Science.gov (United States)

    Treibmann, Stephanie; Hellwig, Anne; Hellwig, Michael; Henle, Thomas

    2017-12-06

    Fructose and dicarbonyl compounds resulting from fructose in heated foods have been linked to pathophysiological pathways of several metabolic disorders. Up to now, very little has been known about the Maillard reaction of fructose in food. Heyns rearrangement compounds (HRCs), the first stable intermediates of the Maillard reaction between amino components and fructose, have not yet been quantitated as protein-bound products in food. Therefore, the HRCs glucosyllysine and mannosyllysine were synthesized and characterized by NMR. Protein-bound HRCs in cookies containing various sugars and in commercial bakery products were quantitated after enzymatic hydrolysis by RP-HPLC-ESI-MS/MS in the multiple reaction monitoring mode through application of the standard addition method. Protein-bound HRCs were quantitated for the first time in model cookies and in commercial bakery products containing honey, banana, and invert sugar syrup. Concentrations of HRCs from 19 to 287 mg/kg were found, which were similar to or exceeded the content of other frequently analyzed Maillard reaction products, such as N-ε-carboxymethyllysine (10-76 mg/kg), N-ε-carboxyethyllysine (2.5-53 mg/kg), and methylglyoxal-derived hydroimidazolone 1 (10-218 mg/kg) in the analyzed cookies. These results show that substantial amounts of HRCs form during food processing. Analysis of protein-bound HRCs in cookies is therefore useful to evaluate the Maillard reaction of fructose.

  10. Synthesis of aldehyde-linked nucleotides and DNA and their bioconjugations with lysine and peptides through reductive amination.

    Science.gov (United States)

    Raindlová, Veronika; Pohl, Radek; Hocek, Michal

    2012-03-26

    5-(5-Formylthienyl)-, 5-(4-formylphenyl)- and 5-(2-fluoro-5-formylphenyl)cytosine 2'-deoxyribonucleoside mono- (dC(R)MP) and triphosphates (dC(R)TP) were prepared by aqueous Suzuki-Miyaura cross-coupling of 5-iodocytosine nucleotides with the corresponding formylarylboronic acids. The dC(R)TPs were excellent substrates for DNA polymerases and were incorporated into DNA by primer extension or PCR. Reductive aminations of the model dC(R)MPs with lysine or lysine-containing tripeptide were studied and optimized. In aqueous phosphate buffer (pH 6.7) the yields of the reductive aminations with tripeptide III were up to 25 %. Bioconjugation of an aldehyde-containing DNA with a lysine-containing tripeptide was achieved through reductive amination in yields of up to 90 % in aqueous phosphate buffer. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Uptake of tritiated lysine by fresh water alga, Scenedesmus obliquus

    International Nuclear Information System (INIS)

    Gogate, S.S.; Krishnamoorthy, T.M.

    1983-01-01

    Tritium uptake by fresh water alga. S.obliquus was studied using tritium labelled lysine, and a sequential solvent extraction procedure was used to study the distribution of tritium in different organic constituents of the algal cells. The accumulation of tritium in the algal cells was found to be 3-4 orders of magnitude more than that obtained for tritiated water. (author)

  12. A review of human pluripotent stem cell-derived cardiomyocytes for high-throughput drug discovery, cardiotoxicity screening, and publication standards.

    Science.gov (United States)

    Mordwinkin, Nicholas M; Burridge, Paul W; Wu, Joseph C

    2013-02-01

    Drug attrition rates have increased in past years, resulting in growing costs for the pharmaceutical industry and consumers. The reasons for this include the lack of in vitro models that correlate with clinical results and poor preclinical toxicity screening assays. The in vitro production of human cardiac progenitor cells and cardiomyocytes from human pluripotent stem cells provides an amenable source of cells for applications in drug discovery, disease modeling, regenerative medicine, and cardiotoxicity screening. In addition, the ability to derive human-induced pluripotent stem cells from somatic tissues, combined with current high-throughput screening and pharmacogenomics, may help realize the use of these cells to fulfill the potential of personalized medicine. In this review, we discuss the use of pluripotent stem cell-derived cardiomyocytes for drug discovery and cardiotoxicity screening, as well as current hurdles that must be overcome for wider clinical applications of this promising approach.

  13. Histone H3 Lysine Methylation in Cognition and Intellectual Disability Disorders

    Science.gov (United States)

    Parkel, Sven; Lopez-Atalaya, Jose P.; Barco, Angel

    2013-01-01

    Recent research indicates that epigenetic mechanisms and, in particular, the post-translational modification (PTM) of histones may contribute to memory encoding and storage. Among the dozens of possible histone PTMs, the methylation/demethylation of lysines in the N-terminal tail of histone H3 exhibits particularly strong links with cognitive…

  14. Acetylome analysis reveals the involvement of lysine acetylation in photosynthesis and carbon metabolism in the model cyanobacterium Synechocystis sp. PCC 6803.

    Science.gov (United States)

    Mo, Ran; Yang, Mingkun; Chen, Zhuo; Cheng, Zhongyi; Yi, Xingling; Li, Chongyang; He, Chenliu; Xiong, Qian; Chen, Hui; Wang, Qiang; Ge, Feng

    2015-02-06

    Cyanobacteria are the oldest known life form inhabiting Earth and the only prokaryotes capable of performing oxygenic photosynthesis. Synechocystis sp. PCC 6803 (Synechocystis) is a model cyanobacterium used extensively in research on photosynthesis and environmental adaptation. Posttranslational protein modification by lysine acetylation plays a critical regulatory role in both eukaryotes and prokaryotes; however, its extent and function in cyanobacteria remain unexplored. Herein, we performed a global acetylome analysis on Synechocystis through peptide prefractionation, antibody enrichment, and high accuracy LC-MS/MS analysis; identified 776 acetylation sites on 513 acetylated proteins; and functionally categorized them into an interaction map showing their involvement in various biological processes. Consistent with previous reports, a large fraction of the acetylation sites are present on proteins involved in cellular metabolism. Interestingly, for the first time, many proteins involved in photosynthesis, including the subunits of phycocyanin (CpcA, CpcB, CpcC, and CpcG) and allophycocyanin (ApcA, ApcB, ApcD, ApcE, and ApcF), were found to be lysine acetylated, suggesting that lysine acetylation may play regulatory roles in the photosynthesis process. Six identified acetylated proteins associated with photosynthesis and carbon metabolism were further validated by immunoprecipitation and Western blotting. Our data provide the first global survey of lysine acetylation in cyanobacteria and reveal previously unappreciated roles of lysine acetylation in the regulation of photosynthesis. The provided data set may serve as an important resource for the functional analysis of lysine acetylation in cyanobacteria and facilitate the elucidation of the entire metabolic networks and photosynthesis process in this model cyanobacterium.

  15. Histone H4 Lysine 20 methylation

    DEFF Research Database (Denmark)

    Jørgensen, Stine; Schotta, Gunnar; Sørensen, Claus Storgaard

    2013-01-01

    of histones have emerged as key regulators of genomic integrity. Intense research during the past few years has revealed histone H4 lysine 20 methylation (H4K20me) as critically important for the biological processes that ensure genome integrity, such as DNA damage repair, DNA replication and chromatin...... compaction. The distinct H4K20 methylation states are mediated by SET8/PR-Set7 that catalyses monomethylation of H4K20, whereas SUV4-20H1 and SUV4-20H2 enzymes mediate further H4K20 methylation to H4K20me2 and H4K20me3. Disruption of these H4K20-specific histone methyltransferases leads to genomic...

  16. Metabolic Availability of the Limiting Amino Acids Lysine and Tryptophan in Cooked White African Cornmeal Assessed in Healthy Young Men Using the Indicator Amino Acid Oxidation Technique.

    Science.gov (United States)

    Rafii, Mahroukh; Elango, Rajavel; Ball, Ronald O; Pencharz, Paul B; Courtney-Martin, Glenda

    2018-06-01

    Maize is a staple food in many regions of the world, particularly in Africa and Latin America. However, maize protein is limiting in the indispensable amino acids lysine and tryptophan, making its protein of poor quality. The main objective of this study was to determine the protein quality of white African cornmeal by determining the metabolic availability (MA) of lysine and tryptophan. To determine the MA of lysine, 4 amounts of l-lysine (10, 13, 16, and 18 mg · kg-1 · d-1 totaling 28.6%, 37.1%, 45.7%, and 51.4% of the mean lysine requirement of 35 mg · kg-1 · d-1, respectively) were studied in 6 healthy young men in a repeated-measures design. To determine the MA of tryptophan, 4 amounts of l-tryptophan (0.5, 1, 1.5, and 2 mg · kg-1 · d-1 totaling 12.5%, 25.0%, 37.5%, and 50.0% of the mean tryptophan requirement of 4 mg · kg-1 · d-1, respectively) were studied in 7 healthy young men in a repeated-measures design. The MAs of lysine and tryptophan were estimated by comparing the indicator amino acid oxidation (IAAO) response with varying intakes of lysine and tryptophan in cooked white cornmeal compared with the IAAO response to l-lysine and l-tryptophan intakes in the reference protein (crystalline amino acid mixture patterned after egg protein) with the use of the slope ratio method. The MAs of lysine and tryptophan from African cooked white cornmeal were 71% and 80%, respectively. Our study provides a robust estimate of the availability of lysine and tryptophan in African white maize to healthy young men. This estimate provides a basis for postproduction fortification or supplementation of maize-based diets. This trial was registered at www.clinicaltrials.gov as NCT02402179.

  17. The effect of amino acid lysine and methionine addition on feed toward the growth and retention on mud crab (Scylla serrata)

    Science.gov (United States)

    Alissianto, Y. R.; Sandriani, Z. A.; Rahardja, B. S.; Agustono; Rozi

    2018-04-01

    High market demand of mud crab (Scylla serrata) encourages farmers to increase the production of mud crab. However, mud crab can not synthesize essential amino acids, so it is necessary to supply essential amino acids such as lysine and methionine in the diet. This study aims to determine the effect of lysine and methionine on feeds to increase growth and retention of mud crabs (Scylla serrata). In this study the amount of lysine amino acid and methionine added to the trash fish diet were: P0 (0: 0%); P1 (0.75: 0.75%); P2 (1: 1%); P3 (1.25: 1.25%); P4 (1.5: 1.5%) with the ratio of lysine and methionine 1: 1. The parameters observed in this study were Survival Rate (SR), Specific Growth Rate (SGR), Feed Conversion Ratio (FCR), Efficiency Feed (EF), protein retention and energy retention. The results of the 35-day maintenance study showed significant differences (P protein retention and no significant effect (P> 0.05) on energy retention and Survival Rate (SR) on mud crab. The best results in this study were found in P4 treatment with addition of lysine amino acids and methionine (1.5: 1.5%).

  18. A Stabilized Demethoxyviridin Derivative Inhibits PI3 kinase

    Science.gov (United States)

    Yuan, Hushan; Pupo, Monica T.; Blois, Joe; Smith, Adam; Weissleder, Ralph; Clardy, Jon; Josephson, Lee

    2009-01-01

    The viridins like demethoxyviridin (Dmv) and wortmannin (Wm) are nanomolar inhibitors of the PI3 kinases, a family of enzymes that play key roles in a host of regulatory processes. Central to the use of these compounds to investigate the role of PI3 kinase in biological systems, or as scaffolds for drug development, are the interrelated issues of stability, chemical reactivity, and bioactivity as inhibitors of PI3 kinase. We found that Dmv was an even more potent inhibitor of PI3 kinase than Wm. However, Dmv was notably less stable than Wm in PBS, with a half-life of 26 min vs Wm’s half-life of 3470 min. Dmv, like Wm, disappeared in culture media with a half-life of less than 1 min. To overcome Dmv’s instability, it was esterified at the C1 position, and then reacted with glycine at the C20 position. The resulting Dmv derivative, termed SA-DmvC20-Gly had a half-life of 218 min in PBS and 64 min in culture media. SA-DmvC20-Gly underwent an exchange reaction at the C20 position with N-acetyl lysine in a manner similar to a WmC20 derivative, WmC20-Proline. SA-DmvC20-Gly inhibited PI3 kinase with an IC50 of 44 nM, compared to Wm’s IC50 of 12 nM. These results indicate that the stability of Dmv can be manipulated by reactions at the C1 and C20 positions, while substantially maintaining its ability to inhibit PI3 kinase. Our results indicate it may be possible to obtain stabilized Dmv derivatives for use as PI3 kinase inhibitors in biological systems. PMID:19523825

  19. Recapitulation of Clinical Individual Susceptibility to Drug-Induced QT Prolongation in Healthy Subjects Using iPSC-Derived Cardiomyocytes

    Directory of Open Access Journals (Sweden)

    Tadahiro Shinozawa

    2017-02-01

    Full Text Available To predict drug-induced serious adverse events (SAE in clinical trials, a model using a panel of cells derived from human induced pluripotent stem cells (hiPSCs of individuals with different susceptibilities could facilitate major advancements in translational research in terms of safety and pharmaco-economics. However, it is unclear whether hiPSC-derived cells can recapitulate interindividual differences in drug-induced SAE susceptibility in populations not having genetic disorders such as healthy subjects. Here, we evaluated individual differences in SAE susceptibility based on an in vitro model using hiPSC-derived cardiomyocytes (hiPSC-CMs as a pilot study. hiPSCs were generated from blood samples of ten healthy volunteers with different susceptibilities to moxifloxacin (Mox-induced QT prolongation. Different Mox-induced field potential duration (FPD prolongation values were observed in the hiPSC-CMs from each individual. Interestingly, the QT interval was significantly positively correlated with FPD at clinically relevant concentrations (r > 0.66 in multiple analyses including concentration-QT analysis. Genomic analysis showed no interindividual significant differences in known target-binding sites for Mox and other drugs such as the hERG channel subunit, and baseline QT ranges were normal. The results suggest that hiPSC-CMs from healthy subjects recapitulate susceptibility to Mox-induced QT prolongation and provide proof of concept for in vitro preclinical trials.

  20. Cloning and sequencing of V genes from anti-osteosarcoma monoclonal antibodies TP-1 and TP-3: Location of lysine residues and implications for radiolabeling

    International Nuclear Information System (INIS)

    Olafsen, Tove; Bruland, Oeyvind S.; Zalutsky, Michael R.; Sandlie, Inger

    1995-01-01

    Monoclonal antibodies TP-1 and TP-3 are of potential utility for the radioimmunodiagnosis of osteosarcoma in both human and canine patients. The V genes of these antibodies were cloned and sequenced and to facilitate radiolabeling of these proteins, the location of the lysine residues within these sequences have been determined. The V-domains of TP-1 contain a total of 12 lysines, 10 in the framework region and 2 in the CDR region, while the V-domains of TP-3 contain a total of 14 lysines, 11 in the framework region and 3 in the CDR regions. Using space-filling models, the availability of each lysine residue for radiolabeling, and potential interference with antigen binding was predicted

  1. Cloning and sequencing of V genes from anti-osteosarcoma monoclonal antibodies TP-1 and TP-3: Location of lysine residues and implications for radiolabeling

    Energy Technology Data Exchange (ETDEWEB)

    Olafsen, Tove; Bruland, Oeyvind S.; Zalutsky, Michael R.; Sandlie, Inger

    1995-08-01

    Monoclonal antibodies TP-1 and TP-3 are of potential utility for the radioimmunodiagnosis of osteosarcoma in both human and canine patients. The V genes of these antibodies were cloned and sequenced and to facilitate radiolabeling of these proteins, the location of the lysine residues within these sequences have been determined. The V-domains of TP-1 contain a total of 12 lysines, 10 in the framework region and 2 in the CDR region, while the V-domains of TP-3 contain a total of 14 lysines, 11 in the framework region and 3 in the CDR regions. Using space-filling models, the availability of each lysine residue for radiolabeling, and potential interference with antigen binding was predicted.

  2. Genealogy profiling through strain improvement by using metabolic network analysis: metabolic flux genealogy of several generations of lysine-producing corynebacteria.

    Science.gov (United States)

    Wittmann, Christoph; Heinzle, Elmar

    2002-12-01

    A comprehensive approach of metabolite balancing, (13)C tracer studies, gas chromatography-mass spectrometry, matrix-assisted laser desorption ionization-time of flight mass spectrometry, and isotopomer modeling was applied for comparative metabolic network analysis of a genealogy of five successive generations of lysine-producing Corynebacterium glutamicum. The five strains examined (C. glutamicum ATCC 13032, 13287, 21253, 21526, and 21543) were previously obtained by random mutagenesis and selection. Throughout the genealogy, the lysine yield in batch cultures increased markedly from 1.2 to 24.9% relative to the glucose uptake flux. Strain optimization was accompanied by significant changes in intracellular flux distributions. The relative pentose phosphate pathway (PPP) flux successively increased, clearly corresponding to the product yield. Moreover, the anaplerotic net flux increased almost twofold as a consequence of concerted regulation of C(3) carboxylation and C(4) decarboxylation fluxes to cover the increased demand for lysine formation; thus, the overall increase was a consequence of concerted regulation of C(3) carboxylation and C(4) decarboxylation fluxes. The relative flux through isocitrate dehydrogenase dropped from 82.7% in the wild type to 59.9% in the lysine-producing mutants. In contrast to the NADPH demand, which increased from 109 to 172% due to the increasing lysine yield, the overall NADPH supply remained constant between 185 and 196%, resulting in a decrease in the apparent NADPH excess through strain optimization. Extrapolated to industrial lysine producers, the NADPH supply might become a limiting factor. The relative contributions of PPP and the tricarboxylic acid cycle to NADPH generation changed markedly, indicating that C. glutamicum is able to maintain a constant supply of NADPH under completely different flux conditions. Statistical analysis by a Monte Carlo approach revealed high precision for the estimated fluxes, underlining the

  3. Dynamic regulation of six histone H3 lysine (K) methyltransferases in response to prolonged anoxia exposure in a freshwater turtle.

    Science.gov (United States)

    Wijenayake, Sanoji; Hawkins, Liam J; Storey, Kenneth B

    2018-04-05

    The importance of histone lysine methylation is well established in health, disease, early development, aging, and cancer. However, the potential role of histone H3 methylation in regulating gene expression in response to extended periods of oxygen deprivation (anoxia) in a natural, anoxia-tolerant model system is underexplored. Red-eared sliders (Trachemys scripta elegans) can tolerate and survive three months of absolute anoxia and recover without incurring detrimental cellular damage, mainly by reducing the overall metabolic rate by 90% when compared to normoxia. Stringent regulation of gene expression is a vital aspect of metabolic rate depression in red-eared sliders, and as such we examined the anoxia-responsive regulation of histone lysine methylation in the liver during 5 h and 20 h anoxia exposure. Interestingly, this is the first study to illustrate the existence of histone lysine methyltransferases (HKMTs) and corresponding histone H3 lysine methylation levels in the liver of anoxia-tolerant red-eared sliders. In brief, H3K4me1, a histone mark associated with active transcription, and two corresponding histone lysine methyltransferases that modify H3K4me1 site, significantly increased in response to anoxia. On the contrary, H3K27me1, another transcriptionally active histone mark, significantly decreased during 20 h anoxia, and a transcriptionally repressive histone mark, H3K9me3, and the corresponding KMTs, similarly increased during 20 h anoxia. Overall, the results suggest a dynamic regulation of histone H3 lysine methylation in the liver of red-eared sliders that could theoretically aid in the selective upregulation of genes that are necessary for anoxia survival, while globally suppressing others to conserve energy. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Functional profiling of microtumors to identify cancer associated fibroblast-derived drug targets.

    Science.gov (United States)

    Horman, Shane R; To, Jeremy; Lamb, John; Zoll, Jocelyn H; Leonetti, Nicole; Tu, Buu; Moran, Rita; Newlin, Robbin; Walker, John R; Orth, Anthony P

    2017-11-21

    Recent advances in chemotherapeutics highlight the importance of molecularly-targeted perturbagens. Although these therapies typically address dysregulated cancer cell proteins, there are increasing therapeutic modalities that take into consideration cancer cell-extrinsic factors. Targeting components of tumor stroma such as vascular or immune cells has been shown to represent an efficacious approach in cancer treatment. Cancer-associated fibroblasts (CAFs) exemplify an important stromal component that can be exploited in targeted therapeutics, though their employment in drug discovery campaigns has been relatively minimal due to technical logistics in assaying for CAF-tumor interactions. Here we report a 3-dimensional multi-culture tumor:CAF spheroid phenotypic screening platform that can be applied to high-content drug discovery initiatives. Using a functional genomics approach we systematically profiled 1,024 candidate genes for CAF-intrinsic anti-spheroid activity; identifying several CAF genes important for development and maintenance of tumor:CAF co-culture spheroids. Along with previously reported genes such as WNT, we identify CAF-derived targets such as ARAF and COL3A1 upon which the tumor compartment depends for spheroid development. Specifically, we highlight the G-protein-coupled receptor OGR1 as a unique CAF-specific protein that may represent an attractive drug target for treating colorectal cancer. In vivo , murine colon tumor implants in OGR1 knockout mice displayed delayed tumor growth compared to tumors implanted in wild type littermate controls. These findings demonstrate a robust microphysiological screening approach for identifying new CAF targets that may be applied to drug discovery efforts.

  5. Dichotomy in the Epigenetic Mark Lysine Acetylation is Critical for the Proliferation of Prostate Cancer Cells

    International Nuclear Information System (INIS)

    Pathak, Ravi; Philizaire, Marc; Mujtaba, Shiraz

    2015-01-01

    The dynamics of lysine acetylation serve as a major epigenetic mark, which regulates cellular response to inflammation, DNA damage and hormonal changes. Microarray assays reveal changes in gene expression, but cannot predict regulation of a protein function by epigenetic modifications. The present study employs computational tools to inclusively analyze microarray data to understand the potential role of acetylation during development of androgen-independent PCa. The data revealed that the androgen receptor interacts with 333 proteins, out of which at least 92 proteins were acetylated. Notably, the number of cellular proteins undergoing acetylation in the androgen-dependent PCa was more as compared to the androgen-independent PCa. Specifically, the 32 lysine-acetylated proteins in the cellular models of androgen-dependent PCa were mainly involved in regulating stability as well as pre- and post-processing of mRNA. Collectively, the data demonstrate that protein lysine acetylation plays a crucial role during the transition of androgen-dependent to -independent PCa, which importantly, could also serve as a functional axis to unravel new therapeutic targets

  6. Dichotomy in the Epigenetic Mark Lysine Acetylation is Critical for the Proliferation of Prostate Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Pathak, Ravi [Department of Structural and Chemical Biology, Mount Sinai School of Medicine, 1425 Madison Ave, New York, NY 10029 (United States); Philizaire, Marc [Medgar Evers College, City University of New York, 1638 Bedford Ave, 403D, Brooklyn, NY 11225 (United States); Mujtaba, Shiraz, E-mail: smujtaba@mec.cuny.edu [Department of Structural and Chemical Biology, Mount Sinai School of Medicine, 1425 Madison Ave, New York, NY 10029 (United States); Medgar Evers College, City University of New York, 1638 Bedford Ave, 403D, Brooklyn, NY 11225 (United States)

    2015-08-19

    The dynamics of lysine acetylation serve as a major epigenetic mark, which regulates cellular response to inflammation, DNA damage and hormonal changes. Microarray assays reveal changes in gene expression, but cannot predict regulation of a protein function by epigenetic modifications. The present study employs computational tools to inclusively analyze microarray data to understand the potential role of acetylation during development of androgen-independent PCa. The data revealed that the androgen receptor interacts with 333 proteins, out of which at least 92 proteins were acetylated. Notably, the number of cellular proteins undergoing acetylation in the androgen-dependent PCa was more as compared to the androgen-independent PCa. Specifically, the 32 lysine-acetylated proteins in the cellular models of androgen-dependent PCa were mainly involved in regulating stability as well as pre- and post-processing of mRNA. Collectively, the data demonstrate that protein lysine acetylation plays a crucial role during the transition of androgen-dependent to -independent PCa, which importantly, could also serve as a functional axis to unravel new therapeutic targets.

  7. Digestible lysine requirement of Nile tilapia from 86 to 227 g fed arginine to lysine balanced dietsExigência de lisina digestível para a tilápia-do-Nilo de 87 a 226 g alimentada com dietas balanceadas para a relação arginina: lisina

    Directory of Open Access Journals (Sweden)

    Tadeu Orlandi Xavier

    2013-09-01

    Full Text Available This study was conducted out to determine the dietary digestible lysine requirements of Nile tilapia from 87 to 226 g. Fish (n = 170; average initial weight = 86.62 ± 4.89 g were distributed 15 1000-L cages, in a completely randomized design with five treatments and three replicates, and fed extruded diets containing 0.88; 1.12; 1.36; 1.59 and 1.83% of digestible lysine, balanced to keep the arginine to lysine ratio as 1.43:1. There was no effect of the dietary lysine levels on whole body moisture and ash. By Linear Response Plateau analysis of lysine levels on daily gain, feed conversion, protein efficiency ratio and rate of protein deposition was estimated requirement of 1.31, 1.03, 1.16 and 1.31 % of lysine, respectively. A quadratic effect of lysine levels on whole body fat deposition ratio and whole body ether extract composition were observed, and the lowest values were estimated with 1.16% and 1.43% of dietary lysine, respectively. An increase of the dietary lysine levels resulted in linear increase on the fillet yield. The digestible lysine requirements of Nile tilapia (87 to 226 g is 1.31%, in diets balanced for arginine to lysine ratio.Este estudo foi realizado com o objetivo de determinar a exigência de lisina digestível em dietas para alevinos de tilápia-do-Nilo de 87 a 226 g. Os peixes (n=300; peso inicial médio = 86,62 ± 4,89 g foram distribuídos em 15 tanques-rede de 1000 L cada, em delineamento inteiramente casualizado com cinco tratamentos e três repetições e alimentados com dietas extrusadas contendo 0,88; 1,12; 1,36; 1,59 e 1,83% de lisina digestível, balanceadas para relação arginina:lisina em 1,43:1. Não foi observado efeito dos níveis de lisina na dieta sobre os teores de umidade e proteína corporal. Pela análise Linear Response Plateau dos níveis de lisina sobre o ganho de peso diário, conversão alimentar, taxa de eficiência proteica e taxa de deposição de proteína, estimou-se exigência de 1,31; 1

  8. Culture and Drug Profiling of Patient Derived Malignant Pleural Effusions for Personalized Cancer Medicine.

    Science.gov (United States)

    Ruiz, Christian; Kustermann, Stefan; Pietilae, Elina; Vlajnic, Tatjana; Baschiera, Betty; Arabi, Leila; Lorber, Thomas; Oeggerli, Martin; Savic, Spasenija; Obermann, Ellen; Singer, Thomas; Rothschild, Sacha I; Zippelius, Alfred; Roth, Adrian B; Bubendorf, Lukas

    2016-01-01

    The use of patients' own cancer cells for in vitro selection of the most promising treatment is an attractive concept in personalized medicine. Human carcinoma cells from malignant pleural effusions (MPEs) are suited for this purpose since they have already adapted to the liquid environment in the patient and do not depend on a stromal cell compartment. Aim of this study was to develop a systematic approach for the in-vitro culture of MPEs to analyze the effect of chemotherapeutic as well as targeted drugs. MPEs from patients with solid tumors were selected for this study. After morphological and molecular characterization, they were cultured in medium supplemented with patient-derived sterile-filtered effusion supernatant. Growth characteristics were monitored in real-time using the xCELLigence system. MPEs were treated with a targeted therapeutic (erlotinib) according to the mutational status or chemotherapeutics based on the recommendation of the oncologists. We have established a robust system for the ex-vivo culture of MPEs and the application of drug tests in-vitro. The use of an antibody based magnetic cell separation system for epithelial cells before culture allowed treatment of effusions with only moderate tumor cell proportion. Experiments using drugs and drug-combinations revealed dose-dependent and specific growth inhibitory effects of targeted drugs. We developed a new approach for the ex-vivo culture of MPEs and the application of drug tests in-vitro using real-time measuring of cell growth, which precisely reproduced the effect of clinically established treatments by standard chemotherapy and targeted drugs. This sets the stage for future studies testing agents against specific targets from genomic profiling of metastatic tumor cells and multiple drug-combinations in a personalized manner.

  9. Culture and Drug Profiling of Patient Derived Malignant Pleural Effusions for Personalized Cancer Medicine.

    Directory of Open Access Journals (Sweden)

    Christian Ruiz

    Full Text Available The use of patients' own cancer cells for in vitro selection of the most promising treatment is an attractive concept in personalized medicine. Human carcinoma cells from malignant pleural effusions (MPEs are suited for this purpose since they have already adapted to the liquid environment in the patient and do not depend on a stromal cell compartment. Aim of this study was to develop a systematic approach for the in-vitro culture of MPEs to analyze the effect of chemotherapeutic as well as targeted drugs.MPEs from patients with solid tumors were selected for this study. After morphological and molecular characterization, they were cultured in medium supplemented with patient-derived sterile-filtered effusion supernatant. Growth characteristics were monitored in real-time using the xCELLigence system. MPEs were treated with a targeted therapeutic (erlotinib according to the mutational status or chemotherapeutics based on the recommendation of the oncologists.We have established a robust system for the ex-vivo culture of MPEs and the application of drug tests in-vitro. The use of an antibody based magnetic cell separation system for epithelial cells before culture allowed treatment of effusions with only moderate tumor cell proportion. Experiments using drugs and drug-combinations revealed dose-dependent and specific growth inhibitory effects of targeted drugs.We developed a new approach for the ex-vivo culture of MPEs and the application of drug tests in-vitro using real-time measuring of cell growth, which precisely reproduced the effect of clinically established treatments by standard chemotherapy and targeted drugs. This sets the stage for future studies testing agents against specific targets from genomic profiling of metastatic tumor cells and multiple drug-combinations in a personalized manner.

  10. 3-Aminomethyl derivatives of 4,11-dihydroxynaphtho[2,3-f]indole-5,10-dione for circumvention of anticancer drug resistance.

    Science.gov (United States)

    Shchekotikhin, Andrey E; Shtil, Alexander A; Luzikov, Yuri N; Bobrysheva, Tatyana V; Buyanov, Vladimir N; Preobrazhenskaya, Maria N

    2005-03-15

    A series of 3-aminomethyl derivatives of 4,11-dihydroxynaphtho[2,3-f]indole-5,10-dione was synthesized by Mannich reaction or by the transamination of 3-dimethylaminomethyl 4,11-dihydroxy- or 4,11-dimethoxynaphtho[2,3-f]indole-5,10-dione. The potency of novel derivatives was tested on a National Cancer Institute panel of 60 human tumor cell lines as well as in cells with genetically defined determinants of cytotoxic drug resistance, P-glycoprotein (Pgp) expression, and p53 inactivation. Mannich derivatives of 4,11-dihydroxynaphtho[2,3-f]indole-5,10-dione with an additional amino function in their side chain, demonstrated equal cytotoxicity against the parental K562 leukemia cells and their Pgp-positive subline, whereas the latter showed approximately 7-fold resistance to adriamycin, a Pgp transported drug. 3-(1-Piperazinyl)methyl and 3-(quinuclidin-3-yl)aminomethyl derivatives of 4,11-dihydroxynaphtho[2,3-f]indole-5,10-dione killed HCT116 colon carcinoma cells (carrying wild type p53) and their p53-null variant within the similar range of concentrations. We conclude that Mannich modification of 4,11-dihydroxynaphtho[2,3-f]indole-5,10-dione, especially when cyclic diamine (e.g., piperazine, quinuclidine) is used, confers an important feature to the resulting compounds, namely, the potency for tumor cells otherwise resistant to a variety of anticancer drugs.

  11. A new perspective on beta-sheet structures using vibrational Raman optical activity: From poly(L-lysine) to the prion protein

    DEFF Research Database (Denmark)

    McColl, L.H.; Blanch, E.W.; Gill, A.C.

    2003-01-01

    -sheet poly(L-lysine) contains up-and-down antiparallel beta-sheets based on the hairpin motif. The ROA spectrum of beta-sheet poly(L-lysine) was compared with ROA data on a number of native proteins containing different types of beta-sheet. Amide I and amide II ROA band patterns observed in beta-sheet poly(L-ly...

  12. Dissecting the Contributions of Cooperating Gene Mutations to Cancer Phenotypes and Drug Responses with Patient-Derived iPSCs

    Directory of Open Access Journals (Sweden)

    Chan-Jung Chang

    2018-05-01

    Full Text Available Summary: Connecting specific cancer genotypes with phenotypes and drug responses constitutes the central premise of precision oncology but is hindered by the genetic complexity and heterogeneity of primary cancer cells. Here, we use patient-derived induced pluripotent stem cells (iPSCs and CRISPR/Cas9 genome editing to dissect the individual contributions of two recurrent genetic lesions, the splicing factor SRSF2 P95L mutation and the chromosome 7q deletion, to the development of myeloid malignancy. Using a comprehensive panel of isogenic iPSCs—with none, one, or both genetic lesions—we characterize their relative phenotypic contributions and identify drug sensitivities specific to each one through a candidate drug approach and an unbiased large-scale small-molecule screen. To facilitate drug testing and discovery, we also derive SRSF2-mutant and isogenic normal expandable hematopoietic progenitor cells. We thus describe here an approach to dissect the individual effects of two cooperating mutations to clinically relevant features of malignant diseases. : Papapetrou and colleagues develop a comprehensive panel of isogenic iPSC lines with SRSF2 P95L mutation and chr7q deletion. They use these cells to identify cellular phenotypes contributed by each genetic lesion and therapeutic vulnerabilities specific to each one and develop expandable hematopoietic progenitor cell lines to facilitate drug discovery. Keywords: induced pluripotent stem cells, myelodysplastic syndrome, CRISPR/Cas9, gene editing, mutational cooperation, splicing factor mutations, spliceosomal mutations, SRSF2, chr7q deletion

  13. Stabilization of collagen nanofibers with l-lysine improves the ability of carbodiimide cross-linked amniotic membranes to preserve limbal epithelial progenitor cells

    Directory of Open Access Journals (Sweden)

    Lai JY

    2014-11-01

    Full Text Available Jui-Yang Lai,1–3 Pei-Ran Wang,1 Li-Jyuan Luo,1 Si-Tan Chen1 1Institute of Biochemical and Biomedical Engineering, 2Biomedical Engineering Research Center, 3Molecular Medicine Research Center, Chang Gung University, Taoyuan, Taiwan, Republic of ChinaAbstract: To overcome the drawbacks associated with limited cross-linking efficiency of carbodiimide modified amniotic membrane, this study investigated the use of L-lysine as an additional amino acid bridge to enhance the stability of a nanofibrous tissue matrix for a limbal epithelial cell culture platform. Results of ninhydrin assays and zeta potential measurements showed that the amount of positively charged amino acid residues incorporated into the tissue collagen chains is highly correlated with the L-lysine -pretreated concentration. The cross-linked structure and hydrophilicity of amniotic membrane scaffolding materials affected by the lysine molecular bridging effects were determined. With an increase in the L-lysine-pretreated concentration from 1 to 30 mM, the cross-linking density was significantly increased and water content was markedly decreased. The variations in resistance to thermal denaturation and enzymatic degradation were in accordance with the number of cross-links per unit mass of amniotic membrane, indicating L-lysine-modulated stabilization of collagen molecules. It was also noteworthy that the carbodiimide cross-linked tissue samples prepared using a relatively high L-lysine-pretreated concentration (ie, 30 mM appeared to have decreased light transmittance and biocompatibility, probably due to the influence of a large nanofiber size and a high charge density. The rise in stemness gene and protein expression levels was dependent on improved cross-link formation, suggesting the crucial role of amino acid bridges in constructing suitable scaffolds to preserve limbal progenitor cells. It is concluded that mild to moderate pretreatment conditions (ie, 3–10 mM L-lysine can

  14. Formation and Inhibition of Nε-(Carboxymethyllysine in Saccharide-Lysine Model Systems during Microwave Heating

    Directory of Open Access Journals (Sweden)

    Bing Li

    2012-10-01

    Full Text Available  Nε-(carboxymethyl lysine (CML is the most abundant advanced glycation end product (AGE, and frequently selected as an AGEs marker in laboratory studies. In this paper, the formation and inhibition of Nε-(carboxymethyllysine in saccharide-lysine model systems during microwave heating have been studied. The microwave heating treatment significantly promoted the formation of CML during Maillard reactions, which was related to the reaction temperature, time and type of saccharide. The order of CML formation for different saccharides was lactose > glucose > sucrose. Then, the inhibition effect on CML by five inhibitors was further examined. According to the results, ascorbic acid and tocopherol did not affect inhibition of CML, in contrast, thiamin, rutin and quercetin inhibited CML formation, and the inhibitory effects were concentration dependent.

  15. Dgroup: DG01504 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ory drug, salicylic acid derivatives ... DG00015 ... Acetylsalicylic acid ... D00109 ... Aspirin (JP17/USP); Aspalon (JAN) ... D05181 ... Aspirin... aluminum (JP17) ... D07579 ... Aspirin calcium salt ... D07580 ... Aspirin DL-lysine (JAN) ... D07581 ... Aspirin... magnesium salt ... D07582 ... Aspirin sodium ... DG00099 ... Olsalazine ... D0

  16. Lysine desuccinylase SIRT5 binds to cardiolipin and regulates the electron transport chain.

    Science.gov (United States)

    Zhang, Yuxun; Bharathi, Sivakama S; Rardin, Matthew J; Lu, Jie; Maringer, Katherine V; Sims-Lucas, Sunder; Prochownik, Edward V; Gibson, Bradford W; Goetzman, Eric S

    2017-06-16

    SIRT5 is a lysine desuccinylase known to regulate mitochondrial fatty acid oxidation and the urea cycle. Here, SIRT5 was observed to bind to cardiolipin via an amphipathic helix on its N terminus. In vitro , succinyl-CoA was used to succinylate liver mitochondrial membrane proteins. SIRT5 largely reversed the succinyl-CoA-driven lysine succinylation. Quantitative mass spectrometry of SIRT5-treated membrane proteins pointed to the electron transport chain, particularly Complex I, as being highly targeted for desuccinylation by SIRT5. Correspondingly, SIRT5 -/- HEK293 cells showed defects in both Complex I- and Complex II-driven respiration. In mouse liver, SIRT5 expression was observed to localize strictly to the periportal hepatocytes. However, homogenates prepared from whole SIRT5 -/- liver did show reduced Complex II-driven respiration. The enzymatic activities of Complex II and ATP synthase were also significantly reduced. Three-dimensional modeling of Complex II suggested that several SIRT5-targeted lysine residues lie at the protein-lipid interface of succinate dehydrogenase subunit B. We postulate that succinylation at these sites may disrupt Complex II subunit-subunit interactions and electron transfer. Lastly, SIRT5 -/- mice, like humans with Complex II deficiency, were found to have mild lactic acidosis. Our findings suggest that SIRT5 is targeted to protein complexes on the inner mitochondrial membrane via affinity for cardiolipin to promote respiratory chain function. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Mechanistic study of ruthenium (III) catalysed oxidation of L-lysine by ...

    Indian Academy of Sciences (India)

    Administrator

    MS received 15 April 2008; revised 2 July 2008. Abstract. The kinetics of Ru(III) catalysed oxidation of L-lysine by diperiodatoargentate (III) (DPA) in alkaline medium at 298 K and a constant ionic strength of 0⋅50 mol dm. –3 was studied spectrophotometri- cally. The oxidation products are aldehyde (5-aminopentanal) and ...

  18. [Molecular cloning, expression and characterization of lysine decarboxylase gene of endophytic fungus Shiraia sp. Slf14 from Huperzia serrata].

    Science.gov (United States)

    Peng, Silu; Yang, Huilin; Zhu, Du; Zhang, Zhibin; Yan, Riming; Wang, Ya

    2016-04-14

    Huperzine A (HupA) was approved as a drug for the treatment of Alzheimer's disease. The HupA biosynthetic pathway was started from lysine decarboxylase (LDC), which catalyzes lysine to cadaverine. In this study, we cloned and expressed an LDC gene from a HupA-producing endophytic fungus, and tested LDC activities. An endophytic fungus Shiraia sp. Slf14 from Huperzia serrata was used. LDC gene was obtained by RT-PCR, and cloned into pET-22b(+) and pET-32a(+) vectors to construct recombinant plasmids pET- 22b-LDC and pET-32a-LDC. These two recombinant plasmids were transformed into E. coli BL21, cultured for 8 h at 24 °C, 200 r/min with 1×10–3 mol/L IPTG into medium to express the LDC proteins, respectively. LDC proteins were purified by Ni2+ affinity chromatography. Catalytic activities were measured by Thin Layer Chromatography. At last, the physicochemical properties and structures of these two LDCs were obtained by bioinformatics software. LDC and Trx-LDC were expressed in E. coli BL21 successfully. SDS-PAGE analysis shows that the molecular weight of LDC and Trx-LDC were 24.4 kDa and 42.7 kDa respectively, which are consistent with bioinformatics analysis. In addition, TLC analysis reveals that both LDC and Trx-LDC had catalytic abilities. This work can provide fundamental data for enriching LDC molecular information and reveal the HupA biosynthetic pathway in endophytic fungi.

  19. Structural and physicochemical characterization of pyridine derivative salts of anti-inflammatory drugs

    Science.gov (United States)

    Nechipadappu, Sunil Kumar; Trivedi, Darshak R.

    2017-08-01

    Salts of common anti-inflammatory drugs mefenamic acid (MFA), tolfenamic acid (TFA) and naproxen (NPX) with various pyridine derivatives (4-amino pyridine (4AP), 4-dimethylaminopyridine (DMAP) and 2-amino pyridine (2AP)) were synthesized by crystal engineering approach based on the pKa values of API's and the salt former. All the salts were characterized systematically by various spectroscopic methods including FT-IR and 1H NMR and the crystal structure was determined by single-crystal X-ray diffraction techniques (SCXRD). DMAP salt of NPX and 2AP salts of MFA and TFA were not obtained in the salt screening experiments. All the molecular salts exhibited 1:1 molecular stoichiometry in the asymmetric unit and except NPX-2AP salt, all the molecular salts included a water molecule in the crystal lattice. Physicochemical and structural properties between drug-drug molecular salts of MFA-4AP, TFA-4AP and NPX-4AP have been evaluated and it was found that these molecular salts were found to be stable for a time period of six months at ambient condition and further hydration of molecular salts were not observed even at accelerated humid conditions (∼75% RH). It was found that 4AP salts of MFA and TFA and DMAP salts of MFA and TFA are isostructural.

  20. The double radio-isotope derivative techniques for the assay of drugs in biological material

    International Nuclear Information System (INIS)

    Riess, W.

    1977-01-01

    The neuroleptic drug opipramol and its deshydroxyethyl metabolite can be determined simultaneously in the same biological sample. Known amounts of 14 C-labelled opipramol and 14 C-labelled metabolite are added to the sample to serve as internal standards. After suitable extraction, both compounds are acetylated by 3 H-labelled acetic anhydride. Together with μg-amounts of carrier compounds, the O-acetyl derivative of opipramol and the N-acetyl derivative of the metabolite are purified and separated by two-dimensional thin-layer chromatography. Each of the derivatives is isolated and counted for 14 C- and 3 H-activity. The 14 C-activities recovered serve to determine the overall yield of the opipramol and metabolite, and to convert the measured 3 H-activity to 100% theoretical yield. From analyses of standard samples, the specific 3 H-activities of the acetyl derivatives were calculated and these values were used to convert the measured 3 H-activites from biological samples to concentrations of original opipramol and metabolite. For both compounds the standard deviations of blank samples were +- 1 ng/ml. For concentrations up to 100 ng/ml the standard deviation was +- 3 ng/ml

  1. Effects of intravenous nonsteroidal antiinflammatory drugs on a C-fiber reflex elicited by a wide range of stimulus intensities in the rat.

    Science.gov (United States)

    Bustamante, D; Paeile, C; Willer, J C; Le Bars, D

    1996-03-01

    A C-fiber reflex elicited by electrical stimulation within the territory of the sural nerve, was recorded from the ipsilateral biceps femoris muscle in anesthetized rats. The temporal evolution of the response was studied using a constant stimulus intensity (3 x threshold) and recruitment curves were built by varying stimulus intensity from 0 to 7 x threshold. The i.v. administration of aspirin, indomethacin, ketoprofen, paracetamol (= acetaminophen) and lysine clonixinate resulted in dose-dependent depressions of the C-fiber reflex by up to 30 to 40%. By contrast, saline was ineffective. High doses of the effective drugs that produced large disturbances in heart rate and/or acid-base equilibrium were not considered in the pharmacological analysis. When a constant level of stimulation was used, different dose-dependent profiles of drug action were observed. Aspirin induced a slow and gradual depression, although indomethacin, ketoprofen and paracetamol produced a peak effect within the first 10-min period and then reached a steady state phase for up to 30 min. The depressive effects of lysine clonixinate appeared more stable. When recruitment curves were built with a range of nociceptive stimulus intensities, all the drugs produced a dose-dependent decrease in the slopes and the areas under the recruitment curves without any major modification in the thresholds. The order of potency was the same for both stimulation paradigms, e.g., aspirin lysine clonixinate = ketoprofen < indomethacin. It is concluded that NSAID elicit significant antinociceptive effects at a central level, which do not depend on the existence of a hyperalgesic or inflammatory state.

  2. Expression and functional analysis of the lysine decarboxylase and copper amine oxidase genes from the endophytic fungus Colletotrichum gloeosporioides ES026.

    Science.gov (United States)

    Zhang, Xiangmei; Wang, Zhangqian; Jan, Saad; Yang, Qian; Wang, Mo

    2017-06-05

    Huperzine A (HupA) isolated from Huperzia serrata is an important compound used to treat Alzheimer's disease (AD). Recently, HupA was reported in various endophytic fungi, with Colletotrichum gloeosporioides ES026 previously isolated from H. serrata shown to produce HupA. In this study, we performed next-generation sequencing and de novo RNA sequencing of C. gloeosporioides ES026 to elucidate the molecular functions, biological processes, and biochemical pathways of these unique sequences. Gene ontology and Kyoto Encyclopedia of Genes and Genomes assignments allowed annotation of lysine decarboxylase (LDC) and copper amine oxidase (CAO) for their conversion of L-lysine to 5-aminopentanal during HupA biosynthesis. Additionally, we constructed a stable, high-yielding HupA-expression system resulting from the overexpression of CgLDC and CgCAO from the HupA-producing endophytic fungus C. gloeosporioides ES026 in Escherichia coli. Quantitative reverse transcription polymerase chain reaction analysis confirmed CgLDC and CgCAO expression, and quantitative determination of HupA levels was assessed by liquid chromatography high-resolution mass spectrometry, which revealed that elevated expression of CgLDC and CgCAO produced higher yields of HupA than those derived from C. gloeosporioides ES026. These results revealed CgLDC and CgCAO involvement in HupA biosynthesis and their key role in regulating HupA content in C. gloeosporioides ES026.

  3. The relationship between DNA synthesis and incorporation of (14C) lysine into different histone fractions in Ehrlich ascites tumour cells

    International Nuclear Information System (INIS)

    Malec, J.; Kornacka, L.; Wojnarowska, M.; Moscicka, M.

    1974-01-01

    The effect of inhibition of DNA synthesis by hydroxyurea on ( 14 C) lysine incorporation into the main four histone fractions in Ehrlich ascites tumor cells, was examined in vitro. The radioactivity of lysine-rich histones, especially of histone f1, was preferentially decreased. The smallest decrease was observed for histone f3. The incorporation into other cellular proteins was but slightly affected. (author)

  4. Lysine sulfonamides as novel HIV-protease inhibitors: Nepsilon-acyl aromatic alpha-amino acids.

    Science.gov (United States)

    Stranix, Brent R; Lavallée, Jean-François; Sévigny, Guy; Yelle, Jocelyn; Perron, Valérie; LeBerre, Nicholas; Herbart, Dominik; Wu, Jinzi J

    2006-07-01

    A series of lysine sulfonamide analogues bearing Nepsilon-acyl aromatic amino acids were synthesized using an efficient synthetic route. Evaluation of these novel protease inhibitors revealed compounds with high potency against wild-type and multiple-protease inhibitor-resistant HIV viruses.

  5. Lysine deacetylase inhibition prevents diabetes by chromatin-independent immunoregulation and beta-cell protection

    NARCIS (Netherlands)

    Christensen, D.P.; Gysemans, C.; Lundh, M.; Dahllof, M.S.; Noesgaard, D.; Schmidt, S.F.; Mandrup, S; Birkbak, N.; Workman, C.T.; Piemonti, L.; Blaabjerg, L.; Monzani, V.; Fossati, G.; Mascagni, P.; Paraskevas, S.; Aikin, R.A.; Billestrup, N.; Grunnet, L.G.; Dinarello, C.A.; Mathieu, C.; Mandrup-Poulsen, T.

    2014-01-01

    Type 1 diabetes is due to destruction of pancreatic beta-cells. Lysine deacetylase inhibitors (KDACi) protect beta-cells from inflammatory destruction in vitro and are promising immunomodulators. Here we demonstrate that the clinically well-tolerated KDACi vorinostat and givinostat revert diabetes

  6. Design of Hybrid Gels Based on Gellan-Cholesterol Derivative and P90G Liposomes for Drug Depot Applications

    Directory of Open Access Journals (Sweden)

    Nicole Zoratto

    2017-05-01

    Full Text Available Gels are extensively studied in the drug delivery field because of their potential benefits in therapeutics. Depot gel systems fall in this area, and the interest in their development has been focused on long-lasting, biocompatible, and resorbable delivery devices. The present work describes a new class of hybrid gels that stem from the interaction between liposomes based on P90G phospholipid and the cholesterol derivative of the polysaccharide gellan. The mechanical properties of these gels and the delivery profiles of the anti-inflammatory model drug diclofenac embedded in such systems confirmed the suitability of these hybrid gels as a good candidate for drug depot applications.

  7. Anti-Aβ drug screening platform using human iPS cell-derived neurons for the treatment of Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Naoki Yahata

    Full Text Available BACKGROUND: Alzheimer's disease (AD is a neurodegenerative disorder that causes progressive memory and cognitive decline during middle to late adult life. The AD brain is characterized by deposition of amyloid β peptide (Aβ, which is produced from amyloid precursor protein by β- and γ-secretase (presenilin complex-mediated sequential cleavage. Induced pluripotent stem (iPS cells potentially provide an opportunity to generate a human cell-based model of AD that would be crucial for drug discovery as well as for investigating mechanisms of the disease. METHODOLOGY/PRINCIPAL FINDINGS: We differentiated human iPS (hiPS cells into neuronal cells expressing the forebrain marker, Foxg1, and the neocortical markers, Cux1, Satb2, Ctip2, and Tbr1. The iPS cell-derived neuronal cells also expressed amyloid precursor protein, β-secretase, and γ-secretase components, and were capable of secreting Aβ into the conditioned media. Aβ production was inhibited by β-secretase inhibitor, γ-secretase inhibitor (GSI, and an NSAID; however, there were different susceptibilities to all three drugs between early and late differentiation stages. At the early differentiation stage, GSI treatment caused a fast increase at lower dose (Aβ surge and drastic decline of Aβ production. CONCLUSIONS/SIGNIFICANCE: These results indicate that the hiPS cell-derived neuronal cells express functional β- and γ-secretases involved in Aβ production; however, anti-Aβ drug screening using these hiPS cell-derived neuronal cells requires sufficient neuronal differentiation.

  8. Expression of M6 and M7 lysin in Mytilus edulis is not restricted to sperm, but occurs also in oocytes and somatic tissue of males and females.

    Science.gov (United States)

    Heß, Anne-Katrin; Bartel, Manuela; Roth, Karina; Messerschmidt, Katrin; Heilmann, Katja; Kenchington, Ellen; Micheel, Burkhard; Stuckas, Heiko

    2012-08-01

    Sperm proteins of marine sessile invertebrates have been extensively studied to understand the molecular basis of reproductive isolation. Apart from molecules such as bindin of sea urchins or lysin of abalone species, the acrosomal protein M7 lysin of Mytilus edulis has been analyzed. M7 lysin was found to be under positive selection, but mechanisms driving the evolution of this protein are not fully understood. To explore functional aspects, this study investigated the protein expression pattern of M7 and M6 lysin in gametes and somatic tissue of male and female M. edulis. The study employs a previously published monoclonal antibody (G26-AG8) to investigate M6 and M7 lysin protein expression, and explores expression of both genes. It is shown that these proteins and their encoding genes are expressed in gametes and somatic tissue of both sexes. This is in contrast to sea urchin bindin and abalone lysin, in which gene expression is strictly limited to males. Although future studies need to clarify the functional importance of both acrosomal proteins in male and female somatic tissue, new insights into the evolution of sperm proteins in marine sessile invertebrates are possible. This is because proteins with male-specific expression (bindin, lysin) might evolve differently than proteins with expression in both sexes (M6/M7 lysin), and the putative function of both proteins in females opens the possibility that the evolution of M6/M7 lysin is under sexual antagonistic selection, for example, mutations beneficial to the acrosomal function that are less beneficial the function in somatic tissue of females. Copyright © 2012 Wiley Periodicals, Inc.

  9. Bioinspired Star-Shaped Poly(l-lysine) Polypeptides: Efficient Polymeric Nanocarriers for the Delivery of DNA to Mesenchymal Stem Cells.

    Science.gov (United States)

    Walsh, David P; Murphy, Robert D; Panarella, Angela; Raftery, Rosanne M; Cavanagh, Brenton; Simpson, Jeremy C; O'Brien, Fergal J; Heise, Andreas; Cryan, Sally-Ann

    2018-05-07

    The field of tissue engineering is increasingly recognizing that gene therapy can be employed for modulating in vivo cellular response thereby guiding tissue regeneration. However, the field lacks a versatile and biocompatible gene delivery platform capable of efficiently delivering transgenes to mesenchymal stem cells (MSCs), a cell type often refractory to transfection. Herein, we describe the extensive and systematic exploration of three architectural variations of star-shaped poly(l-lysine) polypeptide (star-PLL) with varying number and length of poly(l-lysine) arms as potential nonviral gene delivery vectors for MSCs. We demonstrate that star-PLL vectors are capable of self-assembling with pDNA to form stable, cationic nanomedicines. Utilizing high content screening, live cell imaging, and mechanistic uptake studies we confirm the intracellular delivery of pDNA by star-PLLs to MSCs is a rapid process, which likely proceeds via a clathrin-independent mechanism. We identify a star-PLL composition with 64 poly(l-lysine) arms and five l-lysine subunits per arm as a particularly efficient vector that is capable of delivering both reporter genes and the therapeutic transgenes bone morphogenetic protein-2 and vascular endothelial growth factor to MSCs. This composition facilitated a 1000-fold increase in transgene expression in MSCs compared to its linear analogue, linear poly(l-lysine). Furthermore, it demonstrated comparable transgene expression to the widely used vector polyethylenimine using a lower pDNA dose with significantly less cytotoxicity. Overall, this study illustrates the ability of the star-PLL vectors to facilitate efficient, nontoxic nucleic acid delivery to MSCs thereby functioning as an innovative nanomedicine platform for tissue engineering applications.

  10. Specificity determinants for lysine incorporation in Staphylococcus aureus peptidoglycan as revealed by the structure of a MurE enzyme ternary complex.

    Science.gov (United States)

    Ruane, Karen M; Lloyd, Adrian J; Fülöp, Vilmos; Dowson, Christopher G; Barreteau, Hélène; Boniface, Audrey; Dementin, Sébastien; Blanot, Didier; Mengin-Lecreulx, Dominique; Gobec, Stanislav; Dessen, Andréa; Roper, David I

    2013-11-15

    Formation of the peptidoglycan stem pentapeptide requires the insertion of both L and D amino acids by the ATP-dependent ligase enzymes MurC, -D, -E, and -F. The stereochemical control of the third position amino acid in the pentapeptide is crucial to maintain the fidelity of later biosynthetic steps contributing to cell morphology, antibiotic resistance, and pathogenesis. Here we determined the x-ray crystal structure of Staphylococcus aureus MurE UDP-N-acetylmuramoyl-L-alanyl-D-glutamate:meso-2,6-diaminopimelate ligase (MurE) (E.C. 6.3.2.7) at 1.8 Å resolution in the presence of ADP and the reaction product, UDP-MurNAc-L-Ala-γ-D-Glu-L-Lys. This structure provides for the first time a molecular understanding of how this Gram-positive enzyme discriminates between L-lysine and D,L-diaminopimelic acid, the predominant amino acid that replaces L-lysine in Gram-negative peptidoglycan. Despite the presence of a consensus sequence previously implicated in the selection of the third position residue in the stem pentapeptide in S. aureus MurE, the structure shows that only part of this sequence is involved in the selection of L-lysine. Instead, other parts of the protein contribute substrate-selecting residues, resulting in a lysine-binding pocket based on charge characteristics. Despite the absolute specificity for L-lysine, S. aureus MurE binds this substrate relatively poorly. In vivo analysis and metabolomic data reveal that this is compensated for by high cytoplasmic L-lysine concentrations. Therefore, both metabolic and structural constraints maintain the structural integrity of the staphylococcal peptidoglycan. This study provides a novel focus for S. aureus-directed antimicrobials based on dual targeting of essential amino acid biogenesis and its linkage to cell wall assembly.

  11. Investigation of the influence of the feed quantity on the utilisation of synthetic lysine (α-15N-labelled) in broiler chickens

    International Nuclear Information System (INIS)

    Liebert, F.; Gebhardt, G.

    1982-01-01

    A total of 15 broiler chickens was fed with a diet of wheat/wheat gluten supplemented with lysine on three N intake levels (I: 1,500; II: 2,100; III: 3,000 mgN/LW/sub kg//sup 0.67/) between their 11. and 20. day of life and tested with regard to the characteristic data of N metabolisation (N balance experiment) and 15 N incorporation in selected tissues and the whole body of chickens. While N metabolisation did not show any differences of process, the results of 15 N incorporation indicated a little more favorable conditions of utilisation for synthetic lysine in III concerning the whole body and the liver. The level of feed intake must not be neglected as a quantity on the utilisation of synthetic lysine but all the problems connected cannot be explained as a whole by this parameter. For the restrictions of N intake effective in the N balance experiment no negative influence is to be expected with regard to the utilisation of synthetic lysine in comparison to ad libitum feeding. (author)

  12. Bladder carcinogenesis in rats subjected to ureterosigmoidostomy and treated with L-lysine.

    Science.gov (United States)

    Dornelas, Conceição Aparecida; Santos, Alessandra Marques Dos; Correia, Antonio Lucas Oliveira; Juanes, Camila de Carvalho; Coelho, João Paulo Ferreira; Cunha, Bianca Lopes; Maciel, André Vinicius Vieira; Jamacaru, Francisco Vagnaldo Fechine

    2016-01-01

    to evaluate the effect of L-lysine in the bladder and intestinal epithelia in rats submitted to vesicosigmoidostomy. we divided forty Wistar rats into four groups: group I - control group (Sham); group II - submitted to vesicosigmoidostomy and treated with L-lysine 150mg/kg; group III - submitted only to vesicosigmoidostomy; and group IV - received L-lysine 150mg/kg. After eight weeks the animals were sacrificed. in the bladders of all operated animals we observed simple, papillary and nodular hyperplasia of transitional cells, transitional cell papillomas and squamous metaplasia. As for the occurrence of aberrant crypt foci in the colons of operated animals, we did not observe statistically significant differences in any of the distal, proximal and medium fragments, or in all fragments together (p=1.0000). Although statistically there was no promotion of carcinogenesis in the epithelia of rats treated with L-lysine in the observed time, it was clear the histogenesis of bladder carcinogenesis in its initial phase in all operated rats, this being probably associated with chronic infection and tiny bladder stones. o objetivo deste trabalho é avaliar o efeito da L-lisina nos epitélios vesical e intestinal de ratas submetidas à vesicossigmoidostomia. quarenta ratas Wistar, foram divididas em quatro grupos: grupo I- grupo controle (Sham); grupo II- submetido à vesicossigmoidostomia e tratado com L-lisina 150mg/kg; grupo III- submetido apenas à vesicossigmoidostomia; e grupo IV- recebeu L-lisina 150mg/kg. Após oito semanas os animais foram sacrificados. na bexiga de todos os animais operados observou-se hiperplasia simples, papilar e nodular de células transicionais, papiloma de células transicionais e metaplasia escamosa. Quanto à ocorrência de focos de criptas aberrantes nos colos dos animais operados, não foi evidenciado diferença estatística significante em nenhum dos fragmentos distal, proximal e médio, e todos juntos (P=1,0000). apesar de

  13. Effects of intrathecal or intracerebroventricular administration of nonsteroidal anti-inflammatory drugs on a C-fiber reflex in rats.

    Science.gov (United States)

    Bustamante, D; Paeile, C; Willer, J C; Le Bars, D

    1997-06-01

    A C-fiber reflex elicited by electrical stimulation within the territory of the sural nerve was recorded from the ipsilateral biceps femoris muscle in anesthetized rats. The temporal evolution of the response was studied using a constant stimulus intensity (3 times threshold), and recruitment curves were built by varying the stimulus intensity from 0 to 7 times threshold. The intrathecal (i.t.) but not i.c.v. administration of aspirin, indomethacin, ketoprofen and lysine clonixinate resulted in dose-dependent depressions of the C-fiber reflex. In contrast, saline was ineffective. Regardless of the route of administration, the drugs never produced disturbances in heart rate and/or acid-base equilibrium. When a constant level of stimulation was used, 500 microg of aspirin i.t. induced a blockade of the reflex immediately after the injection, followed by a partial recovery. Indomethacin produced a stable depression, which reached 80 to 90% with an i.t. dose of 500 microg. Ketoprofen and lysine clonixinate produced a more stable effect; the highest doses (500 microg) produced a steady-state depression of approximately 50% for approximately 30 min. When the recruitment curves were built with a range of nociceptive stimulus intensities, all of the drugs except for indomethacin produced a dose-dependent decrease in the slopes and the areas under the recruitment curves without major modifications in the thresholds; indomethacin also induced a significant dose-related increase in the threshold. The orders of potency for both stimulation paradigms with the i.t. route were the same, namely aspirin > indomethacin > lysine clonixinate > or = ketoprofen. It is concluded that nonsteroidal anti-inflammatory drugs elicit significant antinociceptive effects at a spinal level, which do not depend on the existence of a hyperalgesic or inflammatory state. Such effects were not seen after injections within the lateral ventricle.

  14. Evaluation of umbilical cord mesenchymal stem cells labeling with superparamagnetic iron oxide nanoparticles coated with dextran and complexed with Poly-L-Lysine; Avaliacao da marcacao de celulas-tronco mesenquimais de cordao umbilical com nanoparticulas superparamagneticas de oxido de ferro recobertas com Dextran e complexadas a Poli-L-Lisina

    Energy Technology Data Exchange (ETDEWEB)

    Sibov, Tatiana Tais; Mamani, Javier Bustamante; Pavon, Lorena Favaro; Cardenas, Walter Humberto; Gamarra, Lionel Fernel, E-mail: tatianats@einstein.br [Instituto do Cerebro - InCe, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Miyaki, Liza Aya Mabuchi [Faculdade de Enfermagem, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Marti, Luciana Cavalheiro; Sardinha, Luiz Roberto [Centro de Pesquisa Experimental, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Oliveira, Daniela Mara de [Universidade de Brasilia - UnB, Brasilia, DF (Brazil)

    2012-04-15

    Objective: The objective of this study was to evaluate the effect of the labeling of umbilical cord vein derived mesenchymal stem cells with superparamagnetic iron oxide nanoparticles coated with dextran and complexed to a non-viral transfector agent transfector poly-L-lysine. Methods: The labeling of mesenchymal stem cells was performed using the superparamagnetic iron oxide nanoparticles/dextran complexed and not complexed to poly-L-lysine. Superparamagnetic iron oxide nanoparticles/dextran was incubated with poly-L-lysine in an ultrasonic sonicator at 37 deg C for 10 minutes for complex formation superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine by electrostatic interaction. Then, the mesenchymal stem cells were incubated overnight with the complex superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine and superparamagnetic iron oxide nanoparticles/dextran. After the incubation period the mesenchymal stem cells were evaluated by internalization of the complex superparamagnetic iron oxide nanoparticles/dextran/polyL-lysine and superparamagnetic iron oxide nanoparticles/dextran by Prussian Blue stain. Cellular viability of labeled mesenchymal stem cells was evaluated by cellular proliferation assay using 5,6-carboxyfluorescein-succinimidyl ester method and apoptosis detection by Annexin V- Propidium Iodide assay. Results: mesenchymal stem cells labeled with superparamagnetic iron oxide nanoparticles/ dextran without poly-L-lysine not internalized efficiently the superparamagnetic iron oxide nanoparticles due to its low presence detected within cells. Mesenchymal stem cells labeled with the complex superparamagnetic iron oxide nanoparticles/dextran/polyL-lysine efficiently internalized the superparamagnetic iron oxide nanoparticles due to greater presence in the cells interior. The viability and apoptosis assays demonstrated that the mesenchymal stem cells labeled and not labeled respectively with the superparamagnetic iron oxide

  15. Exosomes derived from human mesenchymal stem cells confer drug resistance in gastric cancer.

    Science.gov (United States)

    Ji, Runbi; Zhang, Bin; Zhang, Xu; Xue, Jianguo; Yuan, Xiao; Yan, Yongmin; Wang, Mei; Zhu, Wei; Qian, Hui; Xu, Wenrong

    2015-08-03

    Mesenchymal stem cells (MSCs) play an important role in chemoresistance. Exosomes have been reported to modify cellular phenotype and function by mediating cell-cell communication. In this study, we aimed to investigate whether exosomes derived from MSCs (MSC-exosomes) are involved in mediating the resistance to chemotherapy in gastric cancer and to explore the underlying molecular mechanism. We found that MSC-exosomes significantly induced the resistance of gastric cancer cells to 5-fluorouracil both in vivo and ex vivo. MSC-exosomes antagonized 5-fluorouracil-induced apoptosis and enhanced the expression of multi-drug resistance associated proteins, including MDR, MRP and LRP. Mechanistically, MSC-exosomes triggered the activation of calcium/calmodulin-dependent protein kinases (CaM-Ks) and Raf/MEK/ERK kinase cascade in gastric cancer cells. Blocking the CaM-Ks/Raf/MEK/ERK pathway inhibited the promoting role of MSC-exosomes in chemoresistance. Collectively, MSC-exosomes could induce drug resistance in gastric cancer cells by activating CaM-Ks/Raf/MEK/ERK pathway. Our findings suggest that MSC-exosomes have profound effects on modifying gastric cancer cells in the development of drug resistance. Targeting the interaction between MSC-exosomes and cancer cells may help improve the efficacy of chemotherapy in gastric cancer.

  16. One-dimensional poly(L-lysine)-block-poly(L-threonine) assemblies exhibit potent anticancer activity by enhancing membranolysis.

    Science.gov (United States)

    Chen, Yu-Fon; Shiau, Ai-Li; Chang, Sue-Joan; Fan, Nai-Shin; Wang, Chung-Teng; Wu, Chao-Liang; Jan, Jeng-Shiung

    2017-06-01

    Herein, we report the oncolytic activity of cationic, one-dimensional (1D) fibril assemblies formed from coil-sheet poly(L-lysine)-block-poly(L-threonine) (PLL-b-PLT) block copolypeptides for cancer therapy. The 1D fibril assemblies can efficiently interact with negatively charged cellular and mitochondrial membranes via electrostatic interactions, leading to necrosis via membrane lysis and apoptosis via the mitochondria-lytic effect. The concept is analogous to that of 1D drug carriers that exhibit enhanced cell penetration. In comparison to free PLL chains, PLL-b-PLT fibril assemblies exhibit selective cytotoxicity toward cancer cells, low hemolysis activity, enhanced membranolytic activity, and a different apoptosis pathway, which may be due to differences in the peptide-membrane interactions. Antitumor studies using a metastatic LL2 lung carcinoma model indicate that the fibril assemblies significantly inhibited tumor growth, improved survival in tumor-bearing mice and suppressed lung metastasis without obvious body weight loss. An additive efficacy was also observed for treatment with both PLL-b-PLT and cisplatin. These results support the feasibility of using 1D fibril assemblies as potential apoptotic anticancer therapeutics. We report that cationic, one-dimensional (1D) fibril assemblies formed by coil-sheet poly(L-lysine)-block-poly(L-threonine) (PLL-b-PLT) block copolypeptides exhibited potent anticancer activity by enhancing membranolysis. The 1D fibril assemblies can efficiently interact with negatively charged cellular and mitochondrial membranes via electrostatic interactions, leading to necrosis via membrane lysis and apoptosis via mitochondria-lytic effect. Moreover, the fibril assemblies exhibited low hemolytic activity and selective cytotoxicity toward cancer cell, which is advantageous as compared to PLL and most antimicrobial/anticancerous peptides. This study provides a new concept of using cationic, 1D fibril assemblies for cancer therapy

  17. Acetylation site specificities of lysine deacetylase inhibitors in human cells

    DEFF Research Database (Denmark)

    Schölz, Christian; Weinert, Brian Tate; Wagner, Sebastian A

    2015-01-01

    Lysine deacetylases inhibitors (KDACIs) are used in basic research, and many are being investigated in clinical trials for treatment of cancer and other diseases. However, their specificities in cells are incompletely characterized. Here we used quantitative mass spectrometry (MS) to obtain acety......1-α, providing a possible mechanistic explanation of its adverse, pro-inflammatory effects. Our results offer a systems view of KDACI specificities, providing a framework for studying function of acetylation and deacetylases....

  18. Biotin protein ligase from Corynebacterium glutamicum: role for growth and L: -lysine production.

    Science.gov (United States)

    Peters-Wendisch, P; Stansen, K C; Götker, S; Wendisch, V F

    2012-03-01

    Corynebacterium glutamicum is a biotin auxotrophic Gram-positive bacterium that is used for large-scale production of amino acids, especially of L-glutamate and L-lysine. It is known that biotin limitation triggers L-glutamate production and that L-lysine production can be increased by enhancing the activity of pyruvate carboxylase, one of two biotin-dependent proteins of C. glutamicum. The gene cg0814 (accession number YP_225000) has been annotated to code for putative biotin protein ligase BirA, but the protein has not yet been characterized. A discontinuous enzyme assay of biotin protein ligase activity was established using a 105aa peptide corresponding to the carboxyterminus of the biotin carboxylase/biotin carboxyl carrier protein subunit AccBC of the acetyl CoA carboxylase from C. glutamicum as acceptor substrate. Biotinylation of this biotin acceptor peptide was revealed with crude extracts of a strain overexpressing the birA gene and was shown to be ATP dependent. Thus, birA from C. glutamicum codes for a functional biotin protein ligase (EC 6.3.4.15). The gene birA from C. glutamicum was overexpressed and the transcriptome was compared with the control strain revealing no significant gene expression changes of the bio-genes. However, biotin protein ligase overproduction increased the level of the biotin-containing protein pyruvate carboxylase and entailed a significant growth advantage in glucose minimal medium. Moreover, birA overexpression resulted in a twofold higher L-lysine yield on glucose as compared with the control strain.

  19. Exigências de lisina digestível para codornas japonesas na fase de postura Digestible lysine requirements for laying Japanese quails

    Directory of Open Access Journals (Sweden)

    Fernando Guilherme Perazzo Costa

    2008-12-01

    Full Text Available Objetivou-se estimar as exigências nutricionais de lisina digestível para codornas japonesas em postura. Foram utilizadas 240 codornas distribuídas em delineamento de blocos casualizados, com cinco tratamentos, cada um com seis repetições de oito aves. Os tratamentos consistiram de uma ração basal deficiente em lisina e suplementada com L-lisina.HCL, de modo a apresentar 0,88; 0,96; 1,04; 1,12 ou 1,20% de lisina digestível. Avaliaram-se o consumo de ração (CR, a produção de ovos (PR, o peso (PO e a massa (MO do ovo, a conversão alimentar por massa (CMO e por dúzia (CDZ de ovos, os pesos de albúmen (PA, gema (PG e casca (PC, as porcentagens de albúmen (%A, gema (%G e casca (%C e a gravidade específica (GE dos ovos. O nível de lisina digestível da ração influenciou o consumo de ração, enquanto a produção de ovos respondeu de forma quadrática aos níveis de lisina. As demais variáveis analisadas não foram influenciadas pelo nível de lisina digestível da ração. A exigência de lisina digestível para codornas japonesas em postura foi estimada em 1,03% da ração, que corresponde a um consumo diário de 292 mg de lisina digestível.The objective was to estimate the nutritional requirements of digestible lysine for Japanese laying quails. Two hundred and forty Japanese quails were allotted to a completely randomized block designs, with five diets, with six replications of eight birds each. Diets consisted of a basal ration deficient in lysine and supplemented with five levels 0.88, 0.96, 1.04, 1.12 or 1.20% of digestible lysine. Feed consumption, egg production, egg weight and egg mass, feed conversion by egg mass (FCEM and by dozen egg were evaluated. It was also evaluated, albumen weight, yolk weight and shell weight, percentages of albumen, yolk and shell and egg specific gravity. Dietary digestible lysine level linearly influenced feed intake, while egg production was affected in a quadratic faction by digestible

  20. Sirtuin1-regulated lysine acetylation of p66Shc governs diabetes-induced vascular oxidative stress and endothelial dysfunction

    OpenAIRE

    Kumar, Santosh; Kim, Young-Rae; Vikram, Ajit; Naqvi, Asma; Li, Qiuxia; Kassan, Modar; Kumar, Vikas; Bachschmid, Markus M.; Jacobs, Julia S.; Kumar, Ajay; Irani, Kaikobad

    2017-01-01

    Many oxidative stimuli engage the 66-kDa Src homology 2 domain-containing protein (p66Shc) to induce reactive oxygen species (ROS). ROS regulated by p66Shc promotes aging and contributes to cancer, diabetes, obesity, cardiomyopathy, and atherosclerosis. Here we identify a fundamental mechanism that controls p66Shc and p66Shc-regulated ROS. We show that p66Shc is lysine acetylated when cells are faced with an oxidative stimulus (diabetes), and lysine acetylation of p66Shc is obligatory for p66...

  1. Molecular imaging of reduced renal uptake of radiolabelled [DOTA{sup 0},Tyr{sup 3}]octreotate by the combination of lysine and Gelofusine in rats

    Energy Technology Data Exchange (ETDEWEB)

    Rolleman, E.J.; Bernard, B.F.; Breeman, W.A.P.; Forrer, F.; Blois, E. de; Krenning, E.P.; Jong, M. de [Dept. of Nuclear Medicine, Erasmus MC Rotterdam, Nijmegen (Netherlands); Hoppin, J. [Bioscan Inc., Washington, DC (United States); Gotthardt, M.; Boerman, O.C. [Dept. of Nuclear Medicine, Radboud Univ. Hospital, Nijmegen (Netherlands)

    2008-07-01

    Aim: in peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues, kidney uptake of radiolabelled compound is the major dose-limiting factor. We studied the effects of Gelofusine (20 mg) and lysine (100 mg) and the combination of both after injection of therapeutic doses of radiolabelled [DOTA{sup 0},Tyr{sup 3}]octreotate (60 MBq {sup 111}In or 555 MBq {sup 177}Lu labelled to 15 {mu}g peptide) in male Lewis rats. Methods: kidney uptake was measured by single photon emission computed tomography (SPECT) scans with a four-headed multi-pinhole camera (NanoSPECT) at 24 h, 5 and 7 days p. i. and was quantified by volume of interest analysis. For validation the activity concentration in the dissected kidneys was also determined ex vivo using a gamma counter and a dose calibrator. Results: Gelofusine and lysine both reduced kidney uptake of [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate significantly by about 40% at all time points. The combination of Gelofusine and lysine resulted in a 62% inhibition of kidney uptake (p < 0.01 vs. lysine alone). A weak but significant dose-response relationship for Gelofusine, but not for lysine, was found. In a study with [{sup 111}In-DOTA{sup 0},Tyr{sup 3}]octreotate, conclusions drawn from NanoSPECT data were confirmed by biodistribution data. Conclusions: we conclude that rat kidney uptake of radiolabelled somatostatin analogues can be monitored for a longer period in the same animal using animal SPECT. Gelofusine and lysine had equal potential to reduce kidney uptake of therapeutic doses of [{sup 177}Lu-DOTA{sup 0},Tyr{sup 3}]octreotate. The combination of these compounds caused a significantly larger reduction than lysine or Gelofusine alone and may therefore offer new possibilities in PRRT. The NanoSPECT data were validated by standard biodistribution experiments. (orig.)

  2. Highly Stable l-Lysine 6-Dehydrogenase from the Thermophile Geobacillus stearothermophilus Isolated from a Japanese Hot Spring: Characterization, Gene Cloning and Sequencing, and Expression

    Science.gov (United States)

    Heydari, Mojgan; Ohshima, Toshihisa; Nunoura-Kominato, Naoki; Sakuraba, Haruhiko

    2004-01-01

    l-Lysine dehydrogenase, which catalyzes the oxidative deamination of l-lysine in the presence of NAD, was found in the thermophilic bacterium Geobacillus stearothermophilus UTB 1103 and then purified about 3,040-fold from a crude extract of the organism by using four successive column chromatography steps. This is the first report showing the presence of a thermophilic NAD-dependent lysine dehydrogenase. The product of the enzyme catalytic activity was determined to be Δ1-piperideine-6-carboxylate, indicating that the enzyme is l-lysine 6-dehydrogenase (LysDH) (EC 1.4.1.18). The molecular mass of the purified protein was about 260 kDa, and the molecule was determined to be a homohexamer with subunit molecular mass of about 43 kDa. The optimum pH and temperature for the catalytic activity of the enzyme were about 10.1 and 70°C, respectively. No activity was lost at temperatures up to 65°C in the presence of 5 mM l-lysine. The enzyme was relatively selective for l-lysine as the electron donor, and either NAD or NADP could serve as the electron acceptor (NADP exhibited about 22% of the activity of NAD). The Km values for l-lysine, NAD, and NADP at 50°C and pH 10.0 were 0.73, 0.088, and 0.48 mM, respectively. When the gene encoding this LysDH was cloned and overexpressed in Escherichia coli, a crude extract of the recombinant cells had about 800-fold-higher enzyme activity than the extract of G. stearothermophilus. The nucleotide sequence of the LysDH gene encoded a peptide containing 385 amino acids with a calculated molecular mass of 42,239 Da. PMID:14766574

  3. EFFECTS OF L-LYSINE AESCINAT ON INTRACRANIAL PRESSURE IN CRITICALLY ILL PATIENTS WITH SEVERE TRAUMATIC BRAIN INJURY

    Directory of Open Access Journals (Sweden)

    S. S. Petrikov

    2016-01-01

    Full Text Available Abstract. Increased intracranial pressure results in cerebral blood flow decrease and cerebral edema formation. Correction of intracranial hypertension is one of the most important goals of intensive care in patients with severe traumatic brain injury. Objectives To determine the effects of L-lysine aescinat on ICP in patients with severe TBI.Material and methods. Twenty patients with TBI and Glasgow coma scale below 9 enrolled in the study. All patients were operated: 6 patients underwent craniotomy and intracranial hematoma removing; 11 — decompressive craniotomy and intracranial hematoma removing. In 3 patients only ICP-sensor was implanted. ICP-monitoring was used in all patients. Ten patients were randomized to L-lysine aescinat treatment (daily dose of 20 ml for 7 days after surgery (study group, 10 — to standard therapy (control group. We perfomed a comparative analysis of the mean ICP and the incidence of ICH within 7 days after surgery in the study and control groups.Results. The length of ICP monitoring was 6.4±3.7 days: in the control group — 7.6±4.9 days, in the study group — 5.2±1.4 days. Mean intracranial pressure was less in the study group as compared to patients in the control group. The number of intracranial hypertension episodes was higher in the control group compared with patients who received L-lysine aescinat.Conclusion. L-lysine aescinat treatment in patients with severe traumatic brain injury is accompanied by reduction of mean intracranial pressure and the number of intracranial hypertension episodes.

  4. An Automated Platform for Assessment of Congenital and Drug-Induced Arrhythmia with hiPSC-Derived Cardiomyocytes

    Directory of Open Access Journals (Sweden)

    Wesley L. McKeithan

    2017-10-01

    Full Text Available The ability to produce unlimited numbers of human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs harboring disease and patient-specific gene variants creates a new paradigm for modeling congenital heart diseases (CHDs and predicting proarrhythmic liabilities of drug candidates. However, a major roadblock to implementing hiPSC-CM technology in drug discovery is that conventional methods for monitoring action potential (AP kinetics and arrhythmia phenotypes in vitro have been too costly or technically challenging to execute in high throughput. Herein, we describe the first large-scale, fully automated and statistically robust analysis of AP kinetics and drug-induced proarrhythmia in hiPSC-CMs. The platform combines the optical recording of a small molecule fluorescent voltage sensing probe (VoltageFluor2.1.Cl, an automated high throughput microscope and automated image analysis to rapidly generate physiological measurements of cardiomyocytes (CMs. The technique can be readily adapted on any high content imager to study hiPSC-CM physiology and predict the proarrhythmic effects of drug candidates.

  5. Small-scale screening of anticancer drugs acting specifically on neural stem/progenitor cells derived from human-induced pluripotent stem cells using a time-course cytotoxicity test.

    Science.gov (United States)

    Fukusumi, Hayato; Handa, Yukako; Shofuda, Tomoko; Kanemura, Yonehiro

    2018-01-01

    Since the development of human-induced pluripotent stem cells (hiPSCs), various types of hiPSC-derived cells have been established for regenerative medicine and drug development. Neural stem/progenitor cells (NSPCs) derived from hiPSCs (hiPSC-NSPCs) have shown benefits for regenerative therapy of the central nervous system. However, owing to their intrinsic proliferative potential, therapies using transplanted hiPSC-NSPCs carry an inherent risk of undesired growth in vivo . Therefore, it is important to find cytotoxic drugs that can specifically target overproliferative transplanted hiPSC-NSPCs without damaging the intrinsic in vivo stem-cell system. Here, we examined the chemosensitivity of hiPSC-NSPCs and human neural tissue-derived NSPCs (hN-NSPCs) to the general anticancer drugs cisplatin, etoposide, mercaptopurine, and methotrexate. A time-course analysis of neurospheres in a microsphere array identified cisplatin and etoposide as fast-acting drugs, and mercaptopurine and methotrexate as slow-acting drugs. Notably, the slow-acting drugs were eventually cytotoxic to hiPSC-NSPCs but not to hN-NSPCs, a phenomenon not evident in the conventional endpoint assay on day 2 of treatment. Our results indicate that slow-acting drugs can distinguish hiPSC-NSPCs from hN-NSPCs and may provide an effective backup safety measure in stem-cell transplant therapies.

  6. Ex vivo effects of lysine clonixinate on cyclooxygenases in rat lung and stomach preparations.

    Science.gov (United States)

    Franchi, A M; Di Girolamo, G; De los Santos, A R; Marti, M L; Gimeno, M A

    1999-01-01

    Lysine clonixinate (LC) is an anti-inflammatory, anti-pyretic and analgesic drug with minor digestive side effects, which might suggest a weak COX-1 inhibitor. The aim of this study focused on ex vivo effects of LC 40 mg/kg ip and indomethacin (INDO) 10 mg/kg ip in lung and stomach preparations of control rats and LPS-treated rats (5 mg/kg ip). The non-steroidal antiinflammatory drugs were administered concomitantly, following three hours and before one, two or three hours of LPS treatment. Tissues were weighed and incubated in 2 ml of Kress Ringer Bicarbonate buffer containing glucose (11 mM) under an atmosphere of 95% oxygen and 5% CO(2). Approximately 200 mg of tissue were used for each determination; 0.25 microCi of (14)C-arachidonic acid was added to each tube and the tissues were incubated for 60 min. Prostanoids were extracted from the incubation medium and separated by TLC. Results were expressed as a percentage of the total radioactivity of the plates (% of cpm on plate/100 mg ww). It was found that LC animals that were not given LPS did not modify the synthesis of PGE(2); in lung and stomach tissues showing that did not inhibit COX-1 activity. However, LC inhibited clearly the synthesis of PGE(2) in both preparations obtained from LPS-treated animals. The inhibition was shown when the rats were treated concomitantly, 3 h after or 1 or 2 h before the injection of LPS.

  7. Lysine clonixinate in the treatment of primary dysmenorrhea.

    Science.gov (United States)

    Di Girolamo, G; Zmijanovich, R; de los Santos, A R; Martí, M L; Terragno, A

    1996-01-01

    The efficacy and tolerance of Lysine Clonixinate (LC), a NSAID with prostaglandin synthesis inhibiting mechanism was studied in 24 patients with primary dysmenorrhea according to a double-blind randomized crossover Placebo (P) controlled design with patients serving as their own controls. Treatment consisted in administering 1 tablet of LC or P q6h as from onset of menstrual pain during 5 days and 6 menstrual cycles. Patients were controlled monthly as from the 5th day of the cycle, rating changes in pain intensity according to a 4-point scale, presence of pain during pre-, post- and menstrual periods; possible intracycle changes, amount of bleeding, tolerance and related total and general signs and symptoms. Intensity of baseline menstrual pain amounted to 2.9. Menstrual, intramenstrual and postmenstrual pains were observed in 19 out of 24, 24/24 and only 2 out of the 24 patients, respectively. Concomitant symptoms consisted in headache (12), mastalgia (14) and discomfort (12). Results were obtained by averaging the data from the treatment periods with each drug. Menstrual pain was reduced from 2.9 +/- 0.7 to 1.9 +/- 0.7 with P administration and to 0.66 +/- 0.4 with the administration of LC, a highly significant difference between treatments (p < 0.0001). Premenstrual pain was reduced nonsignificantly from 0.79% to 0.58% with P administration and significantly to 0.29% with administration of LC (p < 0.001). Intramenstrual pain affecting all patients at baseline was reduced significantly by 9% with P and also significantly by 50% with LC (p < 0.001). No differences were encountered in concomitant symptoms during P treatment periods while the incidence was significantly reduced with LC (p < 0.0001). No changes in cycle duration or amount of bleeding were observed between treatments. No adverse events were reported.

  8. Fermented liquid feed - Feed processing has a big impact on microbial degradation of free lysine during fermentation

    DEFF Research Database (Denmark)

    Canibe, Nuria; Jensen, Bent Borg

    2010-01-01

    In order to investigate the influence of feed processing on the microbial degradation of free lysine during fermentation of liquid feed, a study at laboratory scale was carried out. Based on a standard Danish grower diet with extra free amino acids added, two treatments were prepared: treatment 1...... a few hours of fermentation, the levels in both treatments became similar. The concentration of acetic acid was higher in the mixture containing the mash feed than in that containing the pelleted feed. The disappearance of free lysine was much higher when mash feed was fermented than when the same...

  9. Synthesis, DNA Binding, and Anticancer Properties of Bis-Naphthalimide Derivatives with Lysine-Modified Polyamine Linkers

    Directory of Open Access Journals (Sweden)

    Yu Huang

    2018-01-01

    Full Text Available A series of bis-naphthalimide derivatives with different diamine linkers were designed and synthesized. All of the synthesized bis-naphthalimide derivatives were characterized by NMR and HRMS spectra. The binding ability between the compounds and CT DNA was evaluated by using UV–Vis titration experiments. The bis-naphthalimide compound with an ethylenediamine linker showed the largest binding constant with CT DNA. Hence, it was used as the model compound to study the DNA binding selectivity by UV–Vis titration aiming at different DNA duplexes. As a result, this compound showed binding preference to AT-rich duplexes. The DNA binding modes of the compounds were also measured by viscosity titration. The cytotoxicity of the compounds was evaluated by MTT assay. Compounds with 1,6-diaminohexane or 1,4-phenylenedimethanamine linkers showed higher cytotoxicity compared with other bis-naphthalimide derivatives.

  10. HSA-based multi-target combination therapy: regulating drugs' release from HSA and overcoming single drug resistance in a breast cancer model.

    Science.gov (United States)

    Gou, Yi; Zhang, Zhenlei; Li, Dongyang; Zhao, Lei; Cai, Meiling; Sun, Zhewen; Li, Yongping; Zhang, Yao; Khan, Hamid; Sun, Hongbing; Wang, Tao; Liang, Hong; Yang, Feng

    2018-11-01

    Multi-drug delivery systems, which may be promising solution to overcome obstacles, have limited the clinical success of multi-drug combination therapies to treat cancer. To this end, we used three different anticancer agents, Cu(BpT)Br, NAMI-A, and doxorubicin (DOX), to build human serum albumin (HSA)-based multi-drug delivery systems in a breast cancer model to investigate the therapeutic efficacy of overcoming single drug (DOX) resistance to cancer cells in vivo, and to regulate the drugs' release from HSA. The HSA complex structure revealed that NAMI-A and Cu(BpT)Br bind to the IB and IIA sub-domain of HSA by N-donor residue replacing a leaving group and coordinating to their metal centers, respectively. The MALDI-TOF mass spectra demonstrated that one DOX molecule is conjugated with lysine of HSA by a pH-sensitive linker. Furthermore, the release behavior of three agents form HSA can be regulated at different pH levels. Importantly, in vivo results revealed that the HSA-NAMI-A-Cu(BpT)Br-DOX complex not only increases the targeting ability compared with a combination of the three agents (the NAMI-A/Cu(BpT)Br/DOX mixture), but it also overcomes DOX resistance to drug-resistant breast cancer cell lines.

  11. Salicylate, diflunisal and their metabolites inhibit CBP/p300 and exhibit anticancer activity.

    Science.gov (United States)

    Shirakawa, Kotaro; Wang, Lan; Man, Na; Maksimoska, Jasna; Sorum, Alexander W; Lim, Hyung W; Lee, Intelly S; Shimazu, Tadahiro; Newman, John C; Schröder, Sebastian; Ott, Melanie; Marmorstein, Ronen; Meier, Jordan; Nimer, Stephen; Verdin, Eric

    2016-05-31

    Salicylate and acetylsalicylic acid are potent and widely used anti-inflammatory drugs. They are thought to exert their therapeutic effects through multiple mechanisms, including the inhibition of cyclo-oxygenases, modulation of NF-κB activity, and direct activation of AMPK. However, the full spectrum of their activities is incompletely understood. Here we show that salicylate specifically inhibits CBP and p300 lysine acetyltransferase activity in vitro by direct competition with acetyl-Coenzyme A at the catalytic site. We used a chemical structure-similarity search to identify another anti-inflammatory drug, diflunisal, that inhibits p300 more potently than salicylate. At concentrations attainable in human plasma after oral administration, both salicylate and diflunisal blocked the acetylation of lysine residues on histone and non-histone proteins in cells. Finally, we found that diflunisal suppressed the growth of p300-dependent leukemia cell lines expressing AML1-ETO fusion protein in vitro and in vivo. These results highlight a novel epigenetic regulatory mechanism of action for salicylate and derivative drugs.

  12. Meal Pattern of Male Rats Maintained on Amino Acid Supplemented Diets: The Effect of Tryptophan, Lysine, Arginine, Proline and Threonine

    Directory of Open Access Journals (Sweden)

    Raghad Ayaso

    2014-07-01

    Full Text Available The macronutrient composition of the diet has been shown to affect food intake, with proteins having distinct effects. The present study investigated the effect of diet supplementation with individual amino acids (tryptophan, lysine, arginine, proline and threonine on meal pattern among male rats. Meal pattern and body weight were monitored for two weeks. Proline and threonine had minimal effects on meal pattern, while the most pronounced changes were observed in the tryptophan group. Both tryptophan and lysine decreased overall food intake, which was translated into a reduction in body weight. The reduced food intake of the tryptophan group was associated with an increase in meal size, intermeal intervals (IMI and meal time and a decrease in meal number. The decrease in the food intake of the lysine group was associated with a reduction in both IMI and meal number, and this was accompanied by an increase in meal time. Arginine increased meal number, while decreasing IMI. Proline and threonine had a minimal effect on meal pattern. Lysine seems to increase satiety, and arginine seems to decrease it, while tryptophan seems to increase satiety and decrease satiation. Accordingly, changes in meal patterns are associated with the type of amino acid added to the diet.

  13. Genetic analysis of vitreous endosperms derived from homozygotic plants for opaque-2 gene in maize (Zea mays L.)

    International Nuclear Information System (INIS)

    Prioli, A.J.; Barbosa, H.M.; Sant'Anna, R.

    1980-01-01

    From experiments in which opaque-2 maize seeds were treated with gamma rays and ethil methanesulfonate, and their respective untreated controls, seeds with hard, vitreous endosperms were obtained. Some of these were completely vitreous, with no evidence of opaque endosperm tissue. Others had very small and few (one to three) areas of opaque tissue. Plants derived from completely vitreous endosperm seeds were self pollinated and crossed to an opaque-2 inbred. The segregation of vitreous to opaque seeds indicated that the normal allele at the opaque-2 locus was responsible for the vitreousity of the endosperm. Lysine content of the vitreous endosperm was comparable to that of normal endosperms. Plants derived from vitreous seeds with few and tiny spots of opaque tissue produced, upon selfing or crossing to the opaque-2 inbred, only opaque-2 seeds. It is concluded that: (a) induced mutation may not be an effective tool to obtain vitreous opaque-2 endosperm with high lysine content; and, (b) there are unknown genetic systems which severely modify the expression of the opaque-2 gene. (Author) [pt

  14. Determination of digestible isoleucine: lysine ratio in diets for laying hens aged 42-58 weeks

    Directory of Open Access Journals (Sweden)

    Heloisa Helena de Carvalho Mello

    2012-05-01

    Full Text Available Two hundred and fifty-two Hy-Line W36 laying hens were allotted in a completely randomized design with 6 treatments, 7 replicates and 6 hens per experimental unit in order to determine the ideal ratio of isoleucine (Ile in relation to lysine (Lys to laying hens aged 42-58 weeks. Experimental diets contained digestible Ile at different levels, resulting in different Ile:Lys ratios (0.73:1; 0.78:1; 0.83:1; 0.88:1; 0.93:1 and 0.98:1. A basal diet was formulated to provide Isoleucine in levels below recommendations. This diet was supplemented with L-isoleucine to make up the 6 diets. Each diet was made isonitrogenous by varying the dietary contents of glutamic acid and isocaloric by adjusting the contents of cornstarch. All essential amino acids were provided proportionally to lysine. Egg production, egg weight, egg mass, feed conversion ratio, albumen, yolk and eggshell contents were recorded and compiled at every 28-day period. No differences were observed in the performance over a wide range of dietary isoleucine concentrations from 5.76 to 7.73 g/kg corresponding to 0.73:1 to 0.98:1 Ile:Lys ratios. The lowest Ile:Lys ratio (0.73:1 was sufficient to ensure satisfactory performance of birds, corresponding to the consumption of 534 mg of isoleucine and 731 mg of lysine/day.

  15. Hydrogel-based 3D model of patient-derived prostate xenograft tumors suitable for drug screening.

    Science.gov (United States)

    Fong, Eliza L S; Martinez, Mariane; Yang, Jun; Mikos, Antonios G; Navone, Nora M; Harrington, Daniel A; Farach-Carson, Mary C

    2014-07-07

    The lack of effective therapies for bone metastatic prostate cancer (PCa) underscores the need for accurate models of the disease to enable the discovery of new therapeutic targets and to test drug sensitivities of individual tumors. To this end, the patient-derived xenograft (PDX) PCa model using immunocompromised mice was established to model the disease with greater fidelity than is possible with currently employed cell lines grown on tissue culture plastic. However, poorly adherent PDX tumor cells exhibit low viability in standard culture, making it difficult to manipulate these cells for subsequent controlled mechanistic studies. To overcome this challenge, we encapsulated PDX tumor cells within a three-dimensional hyaluronan-based hydrogel and demonstrated that the hydrogel maintains PDX cell viability with continued native androgen receptor expression. Furthermore, a differential sensitivity to docetaxel, a chemotherapeutic drug, was observed as compared to a traditional PCa cell line. These findings underscore the potential impact of this novel 3D PDX PCa model as a diagnostic platform for rapid drug evaluation and ultimately push personalized medicine toward clinical reality.

  16. Amphetamine derivative related deaths.

    Science.gov (United States)

    Lora-Tamayo, C; Tena, T; Rodríguez, A

    1997-02-28

    Amphetamine its methylendioxy (methylendioxyamphetamine methylenedioxymethylamphetamine, methylenedioxyethylamphetamine) and methoxy derivatives (p-methoxyamphetamine and p-methoxymethylamphetamine) are widely abused in Spanish society. We present here the results of a systematic study of all cases of deaths brought to the attention of the Madrid department of the Instituto Nacional de Toxicologia from 1993 to 1995 in which some of these drugs have been found in the cadaveric blood. The cases were divided into three categories: amphetamine and derivatives, amphetamines and alcohol, amphetamines and other drugs. Data on age, sex, clinical symptoms, morphological findings, circumstances of death, when known, and concentration of amphetamine derivatives, alcohol and other drugs in blood are given for each group. The information provided here may prove to be useful for the forensic interpretation of deaths which are directly or indirectly related to abuse of amphetamine derivatives.

  17. Human borna disease virus infection impacts host proteome and histone lysine acetylation in human oligodendroglia cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xia [Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016 (China); Department of Neurology, The Fifth People' s Hospital of Shanghai, School of Medicine, Fudan University, Shanghai, 200240 (China); Zhao, Libo [Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016 (China); Department of Neurology, The Third People' s Hospital of Chongqing, 400014 (China); Yang, Yongtao [Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016 (China); Chongqing Key Laboratory of Neurobiology, Chongqing Medical University, Chongqing, 400016 (China); Institute of Neuroscience, Chongqing Medical University, Chongqing, 400016 (China); Bode, Liv [Bornavirus Research Group affiliated to the Free University of Berlin, Berlin (Germany); Huang, Hua [Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016 (China); Chongqing Key Laboratory of Neurobiology, Chongqing Medical University, Chongqing, 400016 (China); Institute of Neuroscience, Chongqing Medical University, Chongqing, 400016 (China); Liu, Chengyu [Chongqing Key Laboratory of Neurobiology, Chongqing Medical University, Chongqing, 400016 (China); Institute of Neuroscience, Chongqing Medical University, Chongqing, 400016 (China); Huang, Rongzhong [Department of Rehabilitative Medicine, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, 400010 (China); Zhang, Liang [Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016 (China); Chongqing Key Laboratory of Neurobiology, Chongqing Medical University, Chongqing, 400016 (China); Institute of Neuroscience, Chongqing Medical University, Chongqing, 400016 (China); and others

    2014-09-15

    Background: Borna disease virus (BDV) replicates in the nucleus and establishes persistent infections in mammalian hosts. A human BDV strain was used to address the first time, how BDV infection impacts the proteome and histone lysine acetylation (Kac) of human oligodendroglial (OL) cells, thus allowing a better understanding of infection-driven pathophysiology in vitro. Methods: Proteome and histone lysine acetylation were profiled through stable isotope labeling for cell culture (SILAC)-based quantitative proteomics. The quantifiable proteome was annotated using bioinformatics. Histone acetylation changes were validated by biochemistry assays. Results: Post BDV infection, 4383 quantifiable differential proteins were identified and functionally annotated to metabolism pathways, immune response, DNA replication, DNA repair, and transcriptional regulation. Sixteen of the thirty identified Kac sites in core histones presented altered acetylation levels post infection. Conclusions: BDV infection using a human strain impacted the whole proteome and histone lysine acetylation in OL cells. - Highlights: • A human strain of BDV (BDV Hu-H1) was used to infect human oligodendroglial cells (OL cells). • This study is the first to reveal the host proteomic and histone Kac profiles in BDV-infected OL cells. • BDV infection affected the expression of many transcription factors and several HATs and HDACs.

  18. Structural and biochemical alterations of human diabetic dermis studied by 3H-lysine incorporation and microscopy

    International Nuclear Information System (INIS)

    Moczar, M.; Allard, R.; Ouzilou, J.; Robert, L.; Pieraggi, M.-T.; Bouissou, H.; Julian, M.

    1976-01-01

    The alteration of the structural organization of dermal connective tissue was studied by light and electron microscopy and by biochemical techniques in normal human and in diabetic patients using skin biopsies. Part of the tissue was used for light and electron microscopy, the rest was incubated in the presence of 3 H-lysine for four hours. The 3 H-lysine labelled biopsies were submitted to a sequential extraction procedure in order to obtain representative macromolecular fractions containing the matrix macromolecules. The extracts were analyzed for their chemical composition and radioactivity. Electron microscopy revealed microstructural modifications of the fibroblasts, of the collagen and elastic fibers in the diabetic dermis. The incorporation pattern of 3 H-lysine into the macromolecular fractions was different in the normal and diabetic skin biopsies. The percentage of total radioactivity incorporated increased significantly in the 1M CaCl 2 extractable fraction and in the 6M urea extractable fraction and decreased significantly in the collagenase and elastase extracts in diabetic skin biopsy. These results demonstrate the existence of morphological and biochemical alterations in diabetic connective tissue (dermis) reflecting alterations in the relative rates of synthesis and/or degradation of the intercellular matrix macromolecules as well as of their microarchitectural arrangement

  19. Human borna disease virus infection impacts host proteome and histone lysine acetylation in human oligodendroglia cells

    International Nuclear Information System (INIS)

    Liu, Xia; Zhao, Libo; Yang, Yongtao; Bode, Liv; Huang, Hua; Liu, Chengyu; Huang, Rongzhong; Zhang, Liang

    2014-01-01

    Background: Borna disease virus (BDV) replicates in the nucleus and establishes persistent infections in mammalian hosts. A human BDV strain was used to address the first time, how BDV infection impacts the proteome and histone lysine acetylation (Kac) of human oligodendroglial (OL) cells, thus allowing a better understanding of infection-driven pathophysiology in vitro. Methods: Proteome and histone lysine acetylation were profiled through stable isotope labeling for cell culture (SILAC)-based quantitative proteomics. The quantifiable proteome was annotated using bioinformatics. Histone acetylation changes were validated by biochemistry assays. Results: Post BDV infection, 4383 quantifiable differential proteins were identified and functionally annotated to metabolism pathways, immune response, DNA replication, DNA repair, and transcriptional regulation. Sixteen of the thirty identified Kac sites in core histones presented altered acetylation levels post infection. Conclusions: BDV infection using a human strain impacted the whole proteome and histone lysine acetylation in OL cells. - Highlights: • A human strain of BDV (BDV Hu-H1) was used to infect human oligodendroglial cells (OL cells). • This study is the first to reveal the host proteomic and histone Kac profiles in BDV-infected OL cells. • BDV infection affected the expression of many transcription factors and several HATs and HDACs

  20. Small-scale screening of anticancer drugs acting specifically on neural stem/progenitor cells derived from human-induced pluripotent stem cells using a time-course cytotoxicity test

    Directory of Open Access Journals (Sweden)

    Hayato Fukusumi

    2018-01-01

    Full Text Available Since the development of human-induced pluripotent stem cells (hiPSCs, various types of hiPSC-derived cells have been established for regenerative medicine and drug development. Neural stem/progenitor cells (NSPCs derived from hiPSCs (hiPSC-NSPCs have shown benefits for regenerative therapy of the central nervous system. However, owing to their intrinsic proliferative potential, therapies using transplanted hiPSC-NSPCs carry an inherent risk of undesired growth in vivo. Therefore, it is important to find cytotoxic drugs that can specifically target overproliferative transplanted hiPSC-NSPCs without damaging the intrinsic in vivo stem-cell system. Here, we examined the chemosensitivity of hiPSC-NSPCs and human neural tissue—derived NSPCs (hN-NSPCs to the general anticancer drugs cisplatin, etoposide, mercaptopurine, and methotrexate. A time-course analysis of neurospheres in a microsphere array identified cisplatin and etoposide as fast-acting drugs, and mercaptopurine and methotrexate as slow-acting drugs. Notably, the slow-acting drugs were eventually cytotoxic to hiPSC-NSPCs but not to hN-NSPCs, a phenomenon not evident in the conventional endpoint assay on day 2 of treatment. Our results indicate that slow-acting drugs can distinguish hiPSC-NSPCs from hN-NSPCs and may provide an effective backup safety measure in stem-cell transplant therapies.

  1. Uninterrupted monitoring of drug effects in human-induced pluripotent stem cell-derived cardiomyocytes with bioluminescence Ca2+ microscopy.

    Science.gov (United States)

    Suzuki, Kazushi; Onishi, Takahito; Nakada, Chieko; Takei, Shunsuke; Daniels, Matthew J; Nakano, Masahiro; Matsuda, Tomoki; Nagai, Takeharu

    2018-05-18

    Cardiomyocytes derived from human-induced pluripotent stem cells are a powerful platform for high-throughput drug screening in vitro. However, current modalities for drug testing, such as electrophysiology and fluorescence imaging have inherent drawbacks. To circumvent these problems, we report the development of a bioluminescent Ca 2+ indicator GmNL(Ca 2+ ), and its application in a customized microscope for high-throughput drug screening. GmNL(Ca 2+ ) gives a 140% signal change with Ca 2+ , and can image drug-induced changes of Ca 2+ dynamics in cultured cells. Since bioluminescence requires application of a chemical substrate, which is consumed over ~ 30 min we made a dedicated microscope with automated drug dispensing inside a light-tight box, to control drug addition. To overcome thermal instability of the luminescent substrate, or small molecule, dual climate control enables distinct temperature settings in the drug reservoir and the biological sample. By combining GmNL(Ca 2+ ) with this adaptation, we could image spontaneous Ca 2+ transients in cultured cardiomyocytes and phenotype their response to well-known drugs without accessing the sample directly. In addition, the bioluminescent strategy demonstrates minimal perturbation of contractile parameters and long-term observation attributable to lack of phototoxicity and photobleaching. Overall, bioluminescence may enable more accurate drug screening in a high-throughput manner.

  2. Investigation of variations in the acrylamide and N(ε) -(carboxymethyl) lysine contents in cookies during baking.

    Science.gov (United States)

    Cheng, Lu; Jin, Cheng; Zhang, Ying

    2014-05-01

    Baking processing is indispensable to determine special sensory prosperities of cookies and induces the formation of some beneficial components such as antioxidants. However, the formation of some Maillard reaction-derived chemical hazards, such as acrylamide (AA) and N(ε) -(carboxymethyl) lysine (CML) in cookies is also a significant consequence of baking processing from a food safety standpoint. This study investigated the effects of baking conditions on the formation of AA and CML, as well as the antioxidant activity (AOA) of cookies. Cookies were baked at various baking temperatures (155 to 230 °C) and times (1.5 to 31 min). AA and CML contents were determined by ultra-performance liquid chromatography-tandem mass spectrometry, respectively. The highest level of AA was obtained in the cookies baked at 155 °C/21 min and 205 °C/11 min (328.93 ± 3.10 μg/kg and 329.29 ± 5.29 μg/kg), while the highest level of CML was obtained in the cookies baked at 230 °C/1.5 min (118.05 ± 0.21 mg/kg). AA was prone to form at relatively low temperature range (155 to 205 °C), however, CML at relatively high temperature range (205 to 230 °C). The CML content was much higher than the AA content in the same set of cookies, by about 2 to 3 orders of magnitude. The AOA of cookies increased at more severe baking conditions. According to the AA and CML content, AOA and sensory properties of cookies, the temperature-time regime of 180 °C/16 min might be a compromised selection. However, only optimizing the baking condition was not enough for manufacture of high-quality cookies. Cookies, a kind of widely consumed bakery products in the world, contain some potentially harmful compounds, like acrylamide (AA) and N(ε) -(carboxymethyl) lysine (CML). AA in cookies has led to public health concern and several research efforts. But CML, another Maillard reaction-derived chemical hazard, has been neglected so far, even though its content is much higher than that of AA in cookies. The

  3. Lysine and arginine reduce the effects of cerebral ischemic insults and inhibit glutamate-induced neuronal activity in rats

    Directory of Open Access Journals (Sweden)

    Takashi Kondoh

    2010-06-01

    Full Text Available Intravenous administration of arginine was shown to be protective against cerebral ischemic insults via nitric oxide production and possibly via additional mechanisms. The present study aimed at evaluating the neuroprotective effects of oral administration of lysine (a basic amino acid, arginine, and their combination on ischemic insults (cerebral edema and infarction and hemispheric brain swelling induced by transient middle cerebral artery occlusion/reperfusion in rats. Magnetic resonance imaging and 2,3,5-triphenyltetrazolium chloride staining were performed two days after ischemia induction. In control animals, the major edematous areas were observed in the cerebral cortex and striatum. The volumes associated with cortical edema were significantly reduced by lysine (2.0 g/kg, arginine (0.6 g/kg, or their combined administration (0.6 g/kg each. Protective effects of these amino acids on infarction were comparable to the inhibitory effects on edema formation. Interestingly, these amino acids, even at low dose (0.6 g/kg, were effective to reduce hemispheric brain swelling. Additionally, the effects of in vivo microiontophoretic (juxtaneuronal applications of these amino acids on glutamate-evoked neuronal activity in the ventromedial hypothalamus were investigated in awake rats. Glutamate-induced neuronal activity was robustly inhibited by microiontophoretic applications of lysine or arginine onto neuronal membranes. Taken together, our results demonstrate the neuroprotective effects of oral ingestion of lysine and arginine against ischemic insults (cerebral edema and infarction, especially in the cerebral cortex, and suggest that suppression of glutamate-induced neuronal activity might be the primary mechanism associated with these neuroprotective effects.

  4. Effect of different levels of L-carnitine and lysine-methionine on broiler blood parameters

    Directory of Open Access Journals (Sweden)

    Babak Hosseintabar

    2015-09-01

    Full Text Available Objetive. In the present study a completely randomized 3×3 factorial design was used to analyze the effects of different levels of L-Carnitine, lysine(Lys and methionine (Met on the blood concentrations of energy, protein and lipid metabolites of male broiler chickens. Materials and methods. A total of 270 newly hatched male broiler chickens (Ross 308 were randomly assigned to 9 groups (ten broilers per replicate and three replicates per treatment. The control group was fed a basal diet, whereas the treatment groups were fed basal diets supplemented with L-Carnitine (0 mg/kg, 75 mg/kg and 150 mg/kg and lysine-methionine (0, 15 and 30% for 42 days. On day 42, one bird was randomly chosen per replication, a blood sample was taken and the blood concentrations of glucose (GLU, uric acid (UAc, triglyceride (TG, VLDL, HDL, LDL, total protein (TP, albumin (Alb and total cholesterol (TC were analyzed. Results. Dietary L-carnitine supplementation had a significant effect (p<0.05 on uric acid (UAc, HDL, LDL, and total cholesterol (TC. The birds feed L-carnitine plus Lys and Met presented the highest plasmatic UAc level and the lowest plasmatic TC and LDL level. Moreover, L-carnitine significantly reduced total cholesterol (TC when compared with both the control group and the birds feed Lys and Met without L-carnitine. Conclusions. A diet with 150 mg/kg L-carnitine plus 15% Lys and Met seems to be enough to sustain low plasmatic TC, LDL and HDL concentrations on male broiler.

  5. L-lysine-L-tartaric acid: New molecular complex with nonlinear optical properties. Structure, vibrational spectra and phase transitions

    International Nuclear Information System (INIS)

    Debrus, S.; Marchewka, M.K.; Baran, J.; Drozd, M.; Czopnik, R.; Pietraszko, A.; Ratajczak, H.

    2005-01-01

    The first X-ray diffraction and vibrational spectroscopic analysis of a novel complex between L-lysine and L-tartaric acid is reported. The structure was solved in two temperatures (320 and 260 K) showing incommensurate phase between them. Room-temperature powder infrared and Raman measurements for the L-lysine-L-tartaric acid molecular complex (1:1) were carried out. DSC measurements on powder samples indicate two phase transitions points at about 295, 300 and 293, 300 K, for heating and cooling, respectively, with noticeable temperature interval between them. Second harmonic generation efficiency d eff =0.35 d eff (KDP)

  6. Identification of catechols as histone-lysine demethylase inhibitors

    DEFF Research Database (Denmark)

    Nielsen, Anders L; Kristensen, Line H; Stephansen, Karen B

    2012-01-01

    Identification of inhibitors of histone-lysine demethylase (HDM) enzymes is important because of their involvement in the development of cancer. An ELISA-based assay was developed for identification of inhibitors of the HDM KDM4C in a natural products library. Based on one of the hits with affinity...... in the low µM range (1, a catechol), a subset of structurally related compounds was selected and tested against a panel of HDMs. In this subset, two inhibitors (2 and 10) had comparable affinities towards KDM4C and KDM6A but no effect on PHF8. One inhibitor restored H3K9me3 levels in KDM4C transfected U2-OS...

  7. ZP Domain Proteins in the Abalone Egg Coat Include a Paralog of VERL under Positive Selection That Binds Lysin and 18-kDa Sperm Proteins

    Science.gov (United States)

    Aagaard, Jan E.; Vacquier, Victor D.; MacCoss, Michael J.; Swanson, Willie J.

    2010-01-01

    Identifying fertilization molecules is key to our understanding of reproductive biology, yet only a few examples of interacting sperm and egg proteins are known. One of the best characterized comes from the invertebrate archeogastropod abalone (Haliotis spp.), where sperm lysin mediates passage through the protective egg vitelline envelope (VE) by binding to the VE protein vitelline envelope receptor for lysin (VERL). Rapid adaptive divergence of abalone lysin and VERL are an example of positive selection on interacting fertilization proteins contributing to reproductive isolation. Previously, we characterized a subset of the abalone VE proteins that share a structural feature, the zona pellucida (ZP) domain, which is common to VERL and the egg envelopes of vertebrates. Here, we use additional expressed sequence tag sequencing and shotgun proteomics to characterize this family of proteins in the abalone egg VE. We expand 3-fold the number of known ZP domain proteins present within the VE (now 30 in total) and identify a paralog of VERL (vitelline envelope zona pellucida domain protein [VEZP] 14) that contains a putative lysin-binding motif. We find that, like VERL, the divergence of VEZP14 among abalone species is driven by positive selection on the lysin-binding motif alone and that these paralogous egg VE proteins bind a similar set of sperm proteins including a rapidly evolving 18-kDa paralog of lysin, which may mediate sperm–egg fusion. This work identifies an egg coat paralog of VERL under positive selection and the candidate sperm proteins with which it may interact during abalone fertilization. PMID:19767347

  8. A Proteomic Approach to Analyze the Aspirin-mediated Lysine Acetylome*

    OpenAIRE

    Tatham, Michael H.; Cole, Christian; Scullion, Paul; Wilkie, Ross; Westwood, Nicholas J.; Stark, Lesley A.; Hay, Ronald T.

    2016-01-01

    This work is supported by Cancer Research UK Grant C434/A13067 (M.H.T & R.T.H) and Wellcome Trust Grant 098391/Z/12/7 (R.T.H.). Aspirin, or acetylsalicylic acid is widely used to control pain, inflammation and fever. Important to this function is its ability to irreversibly acetylate cyclooxygenases at active site serines. Aspirin has the potential to acetylate other amino-acid side-chains, leading to the possibility that aspirin-mediated lysine acetylation could explain some of its as-yet...

  9. Exigência nutricional de lisina digestível para frangos de corte Nutritional requirement of digestible lysine for broiler chickens

    Directory of Open Access Journals (Sweden)

    Walter Amaral Barboza

    2000-08-01

    Full Text Available O objetivo deste trabalho foi determinar, mediante ensaio de digestibilidade, as exigências nutricionais de lisina digestível verdadeira para frangos de corte nas quatro fases de crescimento. Quatro experimentos de desempenho, realizados previamente, permitiram estimar a exigência de lisina total para frangos de corte nas fases de 1 a 21, 15 a 40, 22 a 40 e 42 a 48 dias de idade. Foram utilizados 30 galos, adultos, Leghorn, cecectomizados com peso médio de 2316±190 g, sendo alojados, individualmente, em gaiolas com bandejas coletoras de excretas, utilizando-se o método de alimentação forçada. O delineamento experimental foi inteiramente casualizado, com cinco tratamentos (quatro com dietas e um em jejum e seis repetições. Foram utilizadas as dietas basais das quatro fases de crescimento, contendo 1,0; 0,825; 0,80; e 0,75% de lisina total. Com base nos coeficientes de digestibilidade determinados de 93,3; 93,58; 89,76; e 92,25% e considerando a L-lisina HCL suplementada como 100% digestível, as exigências de lisina digestível verdadeira foram 1,130; 1,075; 0,95; e 0,84% para as fases de 1 a 21, 15 a 40, 22 a 40 e 42 a 48 dias de idade, respectivamente. Ao aplicar o modelo de regressão linear, foram obtidas as equações (% lisina/Mcal = 0,4335 - 0,003284X r² 0,98 e (% lisina/Mcal = 0,41081 - 0,003213X, r² 0,96 para lisina total e digestível, respectivamente, sendo x a idade média das aves, em dias.The objective of this work was to determine, through a digestibility assay, the nutritional requirement of true digestible lysine for broiler chickens, in the four growing phases. Four performance experiments, previously performed, allowed the determination of total lysine requirement of broiler chickens in the periods from 1 to 21, 15 to 40, 22 to 40 and 42 to 48 days of age. Thirty cecectomized adults Leghorn roosters were used, with an average weight of 2316±190 g, and individually caged in batteries with excreta collecting trays

  10. Lysine requirement of the enterally fed term infant in the first month of life

    NARCIS (Netherlands)

    Huang, L.; Hogewind-Schoonenboom, J.E.; de Groof, F.; Twisk, J.W.R.; Voortman, G.J.; Dorst, K.; Schierbeek, H.; Boehm, G.; Huang, Y.; Chen, C.; van Goudoever, J.B.

    2011-01-01

    Background: Infant nutrition has a major impact on child growth and functional development. Low and high intakes of protein or amino acids could have a detrimental effect. Objective: The objective of the study was to determine the lysine requirement of enterally fed term neonates by using the

  11. Synthesis of stereoarray isotope labeled (SAIL) lysine via the "head-to-tail" conversion of SAIL glutamic acid.

    Science.gov (United States)

    Terauchi, Tsutomu; Kamikawai, Tomoe; Vinogradov, Maxim G; Starodubtseva, Eugenia V; Takeda, Mitsuhiro; Kainosho, Masatsune

    2011-01-07

    A stereoarray isotope labeled (SAIL) lysine, (2S,3R,4R,5S,6R)-[3,4,5,6-(2)H(4);1,2,3,4,5,6-(13)C(6);2,6-(15)N(2)]lysine, was synthesized by the "head-to-tail" conversion of SAIL-Glu, (2S,3S,4R)-[3,4-(2)H(2);1,2,3,4,5-(13)C(5);2-(15)N]glutamic acid, with high stereospecificities for all five chiral centers. With the SAIL-Lys in hand, the unambiguous simultaneous stereospecific assignments were able to be established for each of the prochiral protons within the four methylene groups of the Lys side chains in proteins.

  12. Structural basis for G9a-like protein lysine methyltransferase inhibition by BIX-01294

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Yanqi; Zhang, Xing; Horton, John R.; Upadhyay, Anup K.; Spannhoff, Astrid; Liu, Jin; Synder, James P.; Bedford, Mark T.; Cheng, Xiaodong; (Emory-MED); (Emory); (Texas)

    2009-03-26

    Histone lysine methylation is an important epigenetic mark that regulates gene expression and chromatin organization. G9a and G9a-like protein (GLP) are euchromatin-associated methyltransferases that repress transcription by methylating histone H3 Lys9. BIX-01294 was originally identified as a G9a inhibitor during a chemical library screen of small molecules and has previously been used in the generation of induced pluripotent stem cells. Here we present the crystal structure of the catalytic SET domain of GLP in complex with BIX-01294 and S-adenosyl-L-homocysteine. The inhibitor is bound in the substrate peptide groove at the location where the histone H3 residues N-terminal to the target lysine lie in the previously solved structure of the complex with histone peptide. The inhibitor resembles the bound conformation of histone H3 Lys4 to Arg8, and is positioned in place by residues specific for G9a and GLP through specific interactions.

  13. The Role of Nuclear Receptor-Binding SET Domain Family Histone Lysine Methyltransferases in Cancer.

    Science.gov (United States)

    Bennett, Richard L; Swaroop, Alok; Troche, Catalina; Licht, Jonathan D

    2017-06-01

    The nuclear receptor-binding SET Domain (NSD) family of histone H3 lysine 36 methyltransferases is comprised of NSD1, NSD2 (MMSET/WHSC1), and NSD3 (WHSC1L1). These enzymes recognize and catalyze methylation of histone lysine marks to regulate chromatin integrity and gene expression. The growing number of reports demonstrating that alterations or translocations of these genes fundamentally affect cell growth and differentiation leading to developmental defects illustrates the importance of this family. In addition, overexpression, gain of function somatic mutations, and translocations of NSDs are associated with human cancer and can trigger cellular transformation in model systems. Here we review the functions of NSD family members and the accumulating evidence that these proteins play key roles in tumorigenesis. Because epigenetic therapy is an important emerging anticancer strategy, understanding the function of NSD family members may lead to the development of novel therapies. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  14. Phenolic compounds reduce formation of Nε-(carboxymethyl)lysine and pyrazines formed by Maillard reactions in a model bread system.

    Science.gov (United States)

    Mildner-Szkudlarz, Sylwia; Siger, Aleksander; Szwengiel, Artur; Przygoński, Krzysztof; Wojtowicz, Elżbieta; Zawirska-Wojtasiak, Renata

    2017-09-15

    This study had the objective of determining the antiglycation activity of phenolic compounds (PCs) ((+)-catechin, quercetin, gallic, ferulic, and caffeic acids) added to a model bread with regards to the inhibition of N ε -(carboxymethyl)lysine (CML) formation. PCs were found to significantly reduce CML (31.77%-87.56%), even at the lowest concentration, with the exception of ferulic acid (FA). The strongest inhibitory effect of FA (∼62%) appeared when concentration was increased to 1.0g/100g of flour. The available lysine losses (0.00%-90.51%) showed a significant correlation (0.853-0.990) with effectiveness of CML inhibition, except in the case of samples with FA. (+)-Catechin reduced CML levels the most, probably due to its structure-antioxidant activity relationship, its thermal stability (∼51% loss), and its reactivity with ε-lysine side chains (∼40.77% loss). Although the bread supplemented with PCs contained low levels of CML, this process may adversely affect bread flavor, reducing the formation of pyrazines (1.10%-80.77%). Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Synthesis of [13C6]-labelled phenethylamine derivatives for drug quantification in biological samples.

    Science.gov (United States)

    Karlsen, Morten; Liu, HuiLing; Berg, Thomas; Johansen, Jon Eigill; Hoff, Bård Helge

    2014-05-15

    The availability of high-quality (13)C-labelled internal standards will improve accurate quantification of narcotics and drugs in biological samples. Thus, the synthesis of 10 [(13)C6]-labelled phenethylamine derivatives, namely amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, 3,4-methylenedioxy-N-ethylamphetamine, 4-methoxyamphetamine, 4-methoxymethamphetamine, 3,5-dimethoxyphenethylamine 4-bromo-2,5-dimethoxyphenethylamine and 2,5-dimethoxy-4-iodophenethylamine, have been undertaken. [(13)C6]-Phenol proved to be an excellent starting material for making (13)C-labelled narcotic substances in the phenethylamine class, and a developed Stille-type coupling enabled an efficient synthesis of the 3,4-methylenedioxy and 4-methoxy derivatives. The pros and cons of alternative routes and transformations are also discussed. The [(13)C6]-labelled compounds are intended for use as internal standards in forensic analysis, health sciences and metabolomics studies by gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry. Copyright © 2014 John Wiley & Sons, Ltd.

  16. Human METTL20 methylates lysine residues adjacent to the recognition loop of the electron transfer flavoprotein in mitochondria.

    Science.gov (United States)

    Rhein, Virginie F; Carroll, Joe; He, Jiuya; Ding, Shujing; Fearnley, Ian M; Walker, John E

    2014-08-29

    In mammalian mitochondria, protein methylation is a relatively uncommon post-transcriptional modification, and the extent of the mitochondrial protein methylome, the modifying methyltransferases, and their substrates have been little studied. As shown here, the β-subunit of the electron transfer flavoprotein (ETF) is one such methylated protein. The ETF is a heterodimer of α- and β-subunits. Lysine residues 199 and 202 of mature ETFβ are almost completely trimethylated in bovine heart mitochondria, whereas ETFα is not methylated. The enzyme responsible for the modifications was identified as methyltransferase-like protein 20 (METTL20). In human 143B cells, the methylation of ETFβ is less extensive and is diminished further by suppression of METTL20. Tagged METTL20 expressed in HEK293T cells specifically associates with the ETF and promotes the trimethylation of ETFβ lysine residues 199 and 202. ETF serves as a mobile electron carrier linking dehydrogenases involved in fatty acid oxidation and one-carbon metabolism to the membrane-associated ubiquinone pool. The methylated residues in ETFβ are immediately adjacent to a protein loop that recognizes and binds to the dehydrogenases. Suppression of trimethylation of ETFβ in mouse C2C12 cells oxidizing palmitate as an energy source reduced the consumption of oxygen by the cells. These experiments suggest that the oxidation of fatty acids in mitochondria and the passage of electrons via the ETF may be controlled by modulating the protein-protein interactions between the reduced dehydrogenases and the β-subunit of the ETF by trimethylation of lysine residues. METTL20 is the first lysine methyltransferase to be found to be associated with mitochondria. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Free Base Lysine Increases Survival and Reduces Metastasis in Prostate Cancer Model.

    Science.gov (United States)

    Ibrahim-Hashim, Arig; Wojtkowiak, Jonathan W; de Lourdes Coelho Ribeiro, Maria; Estrella, Veronica; Bailey, Kate M; Cornnell, Heather H; Gatenby, Robert A; Gillies, Robert J

    2011-11-19

    Malignant tumor cells typically metabolize glucose anaerobically to lactic acid even under normal oxygen tension, a phenomenon called aerobic glycolysis or the Warburg effect. This results in increased acid production and the acidification of the extracellular microenvironment in solid tumors. H + ions tend to flow along concentration gradients into peritumoral normal tissue causing extracellular matrix degradation and increased tumor cell motility thus promoting invasion and metastasis. We have shown that reducing this acidity with sodium bicarbonate buffer decreases the metastatic fitness of circulating tumor cells in prostate cancer and other cancer models. Mathematical models of the tumor-host dynamics predicted that buffers with a pka around 7 will be more effective in reducing intra- and peri-tumoral acidosis and, thus, and possibly more effective in inhibiting tumor metastasis than sodium bicarbonate which has a pKa around 6. Here we test this prediction the efficacy of free base lysine; a non-bicarbonate/non-volatile buffer with a higher pKa (~10), on prostate tumor metastases model. Oxygen consumption and acid production rate of PC3M prostate cancer cells and normal prostate cells were determined using the Seahorse Extracellular Flux (XF-96) analyzer. In vivo effect of 200 mM lysine started four days prior to inoculation on inhibition of metastasis was examined in PC3M-LUC-C6 prostate cancer model using SCID mice. Metastases were followed by bioluminescence imaging. PC3M prostate cancer cells are highly acidic in comparison to a normal prostate cell line indicating that reduction of intra- and perit-tumoral acidosis should inhibit metastases formation. In vivo administration of 200 mM free base lysine increased survival and reduced metastasis. PC3M prostate cancer cells are highly glycolytic and produce large amounts of acid when compared to normal prostate cells. Administration of non-volatile buffer decreased growth of metastases and improved survival

  18. The ability of retention, drug release and rheological properties of nanogel bioadhesives based on cellulose derivatives.

    Science.gov (United States)

    Keshavarz, M; Kaffashi, B

    2014-12-01

    The rheological and drug release behavior of biopolymer nanocomposite gels based on the cellulose derivatives, formulated as the bioadhesive drug delivery platforms, were investigated. The bioadhesive gel is composed of the microcrystalline cellulose, sodium carboxymethyl cellulose and phosphate buffered saline (pH = 7.4 at 20 °C) as the dissolution and release medium. The reinforcing nanofillers such as MMT-clay, fumed porous silica and porous starch were used as additives in the nanogel bioadhesive. The constant steady state viscosities of this nanogels upon incorporation of various nanofillers into the systems is the sign of structural stability. Hence, this system is suitable for use in the controlled drug delivery systems in contact with the biological tissues. Based on the rheological measurements, the shear flow properties (i.e. zero shear viscosity and yield stress) were influenced by the concentration of polymers and nanoparticles. The results indicate that the nonlinear rheological data are fitted properly by the Giesekus model. Furthermore, the results showed that the nonlinear viscoelastic parameters (λ and α) are highly affected by the biogel and nanoparticles concentrations. Finally, the drug release was measured, and the results indicated that the biopolymer-clay nanocomposites have appropriate release pattern as the release is better controlled compared to the other nanogel formulations.

  19. Photoinduced electron transfer in singly labeled thiouredopyrenetrisulfonate azurin derivatives

    DEFF Research Database (Denmark)

    Borovok, N; Kotlyar, A B; Pecht, I

    1999-01-01

    efficiency. TUPS derivatives of azurin, singly labeled at specific lysine residues, were prepared and purified to homogeneity by ion exchange HPLC. Transient absorption spectroscopy was used to directly monitor the rates of the electron transfer reaction from the photoexcited triplet state of TUPS to Cu......A novel method for the initiation of intramolecular electron transfer reactions in azurin is reported. The method is based on laser photoexcitation of covalently attached thiouredopyrenetrisulfonate (TUPS), the reaction that generates the low potential triplet state of the dye with high quantum......(II) and the back reaction from Cu(I) to the oxidized dye. For all singly labeled derivatives, the rate constants of copper ion reduction were one or two orders of magnitude larger than for its reoxidation, consistent with the larger thermodynamic driving force for the former process. Using 3-D coordinates...

  20. Adolescent alcohol exposure alters lysine demethylase 1 (LSD1) expression and histone methylation in the amygdala during adulthood.

    Science.gov (United States)

    Kyzar, Evan J; Zhang, Huaibo; Sakharkar, Amul J; Pandey, Subhash C

    2017-09-01

    Alcohol exposure in adolescence is an important risk factor for the development of alcoholism in adulthood. Epigenetic processes are implicated in the persistence of adolescent alcohol exposure-related changes, specifically in the amygdala. We investigated the role of histone methylation mechanisms in the persistent effects of adolescent intermittent ethanol (AIE) exposure in adulthood. Adolescent rats were exposed to 2 g/kg ethanol (2 days on/off) or intermittent n-saline (AIS) during postnatal days (PND) 28-41 and used for behavioral and epigenetic studies. We found that AIE exposure caused a long-lasting decrease in mRNA and protein levels of lysine demethylase 1(Lsd1) and mRNA levels of Lsd1 + 8a (a neuron-specific splice variant) in specific amygdaloid structures compared with AIS-exposed rats when measured at adulthood. Interestingly, AIE increased histone H3 lysine 9 dimethylation (H3K9me2) levels in the central nucleus of the amygdala (CeA) and medial nucleus of the amygdala (MeA) in adulthood without producing any change in H3K4me2 protein levels. Acute ethanol challenge (2 g/kg) in adulthood attenuated anxiety-like behaviors and the decrease in Lsd1 + 8a mRNA levels in the amygdala induced by AIE. AIE caused an increase in H3K9me2 occupancy at the brain-derived neurotrophic factor exon IV promoter in the amygdala that returned to baseline after acute ethanol challenge in adulthood. These results indicate that AIE specifically modulates epizymes involved in H3K9 dimethylation in the amygdala in adulthood, which are possibly responsible for AIE-induced chromatin remodeling and adult psychopathology such as anxiety. © Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  1. Distribution of blood derivatives by registered blood establishments that qualify as health care entities; Prescription Drug Marketing Act of 1987; Prescription Drug Amendments of 1992; delay of applicability date. Final rule; delay of applicability date.

    Science.gov (United States)

    2006-11-13

    The Food and Drug Administration (FDA) is further delaying, until December 1, 2008, the applicability date of a certain requirement of a final rule published in the Federal Register of December 3, 1999 (64 FR 67720) (the final rule). The final rule implements the Prescription Drug Marketing Act of 1987 (PDMA), as modified by the Prescription Drug Amendments of 1992 (PDA), and the Food and Drug Administration Modernization Act of 1997 (the Modernization Act). The provisions of the final rule became effective on December 4, 2000, except for certain provisions whose effective or applicability dates were delayed in five subsequent Federal Register notices, until December 1, 2006. The provision with the delayed applicability date would prohibit wholesale distribution of blood derivatives by registered blood establishments that meet the definition of a "health care entity." In the Federal Register of February 1, 2006 (71 FR 5200), FDA published a proposed rule specific to the distribution of blood derivatives by registered blood establishments that qualify as health care entities (the proposed rule). The proposed rule would amend certain limited provisions of the final rule to allow certain registered blood establishments that qualify as health care entities to distribute blood derivatives. In response to the proposed rule, FDA received substantive comments. As explained in the SUPPLEMENTARY INFORMATION section of this document, further delaying the applicability of Sec. 203.3(q) (21 CFR 203.3(q)) to the wholesale distribution of blood derivatives by health care entities is necessary to give the agency additional time to address comments on the proposed rule, consider whether regulatory changes are appropriate, and, if so, to initiate such changes.

  2. X-ray studies on crystalline complexes involving amino acids and peptides. XXXII. Effect of chirality on ionisation state, stoichiometry and aggregation in the complexes of oxalic acid with DL- and L-lysine.

    Science.gov (United States)

    Venkatraman, J; Prabu, M M; Vijayan, M

    1997-08-01

    Crystals of the oxalic acid complex of DL-lysine (triclinic P1; a = 5.540(1), b = 10.764(2), c = 12.056(2) A, alpha = 77.8(1), beta = 80.6(1), gamma = 75.6(1).; R = 4.7% for 2023 observed reflections) contain lysine and semioxalate ions in the 1:1 ratio, whereas the ratio of lysine and semioxalate/oxalate ions is 2:3 in the crystals of the L-lysine complex (monoclinic P2(1); alpha = 4.906(1), b = 20.145(4), c = 12.455(1) A, beta = 92.5(1).; R = 4.4% for 1494 observed reflections). The amino acid molecule in the L-lysine complex has an unusual ionisation state with positively charged alpha- and side-chain amino groups and a neutral carboxyl group. The unlike molecules aggregate into separate alternating layers in the DL-lysine complex in a manner similar to that observed in several of the amino acid complexes. The L-lysine complex exhibits a new aggregation pattern which cannot be easily explained in terms of planar features, thus emphasizing the fundamental dependence of aggregation on molecular characteristics. Despite the differences in stoichiometry, ionisation state and long-range aggregation patterns, the basic element of aggregation in the two complexes exhibits considerable similarity.

  3. Bovine milk-derived exosomes for drug delivery

    Science.gov (United States)

    Gupta, Ramesh C.

    2015-01-01

    Exosomes are biological nanovesicles that are involved in cell-cell communication via the functionally-active cargo (such as miRNA, mRNA, DNA and proteins). Because of their nanosize, exosomes are explored as nanodevices for the development of new therapeutic applications. However, bulk, safe and cost-effective production of exosomes is not available. Here, we show that bovine milk can serve as a scalable source of exosomes that can act as a carrier for chemotherapeutic/chemopreventive agents. Drug-loaded exosomes showed significantly higher efficacy compared to free drug in cell culture studies and against lung tumor xenografts in vivo. Moreover, tumor targeting ligands such as folate increased cancer-cell targeting of the exosomes resulting in enhanced tumor reduction. Milk exosomes exhibited cross-species tolerance with no adverse immune and inflammatory response. Thus, we show the versatility of milk exosomes with respect to the cargo it can carry and ability to achieve tumor targetability. This is the first report to identify a biocompatible and cost-effective means of exosomes to enhance oral bioavailability, improve efficacy and safety of drugs. PMID:26604130

  4. Electrosynthesis of Clozapine Drug Derivative via an EC Electrochemical Mechanism

    Directory of Open Access Journals (Sweden)

    Esmail Tammari

    2017-12-01

    Full Text Available The fact that oxidation, as one of the main routes of phase I metabolism of drugs, follows by conjugation reactions, and also formation of nitrenium ion as one of the clozapine oxidation products, directed us to investigate the oxidation of clozapine (CLZ in the presence of nucleophile. The oxidation of clozapine (CLZ has been studied on a glassy carbon electrode in the absence and presence of 2-thiobarbituric acid (TBA as nucleophile in aqueous medium by means of cyclic voltammetry and on the graphite rods in controlled-potential coulometry. Cyclic voltammetry studies were realized for CLZ in the pHs 1.0 to 8.0. Results indicate that the electrochemical behavior of CLZ depends on the pH. Based on the obtained electrochemical results, an ECE mechanism was proposed to explain the electrochemical oxidation of CLZ. The results revealed that oxidized CLZ participates in Michael type addition reaction with TBA and via an EC mechanism converts to the corresponding new dibenzodiazepin derivatives. The product has been characterized by IR, 1H NMR, 13C NMR and MS.

  5. Contribution of Histidine and Lysine to the Generation of Volatile Compounds in Jinhua Ham Exposed to Ripening Conditions Via Maillard Reaction.

    Science.gov (United States)

    Zhu, Chao-Zhi; Zhao, Jing-Li; Tian, Wei; Liu, Yan-Xia; Li, Miao-Yun; Zhao, Gai-Ming

    2018-01-01

    To evaluate the role of Maillard reactions in the generation of flavor compounds in Jinhua ham, the reactions of glucose and ethanal with histidine and lysine, respectively, were studied by simulating the ripening conditions of Jinhua ham. The volatile products produced were analyzed using solid phase microextraction-gas chromatography/mass spectrometry. The results showed that 8 volatile compounds were generated by the reaction of glucose and histidine and 10 volatile compounds were generated by the reaction of glucose and lysine. Reactions of ethanal with lysine and with histidine both generated 31 volatile compounds that contributed to the flavor of Jinhua ham. This indicates that histidine and lysine related to Maillard reactions possibly play important roles in the generation of the unique flavor compounds in Jinhua ham. This research demonstrates that free amino acids participate in the generation of volatile compounds from Jinhua ham via the Maillard reaction and provides a basic mechanism to explain flavor formation in Jinhua ham. Jinhua ham is a well-known traditional Chinese dry-cured meat product. However, the formation of the compounds comprising its special flavor is not well understood. Our results indicate that Maillard reactions occur in Jinhua ham under ripening conditions. This work illustrates the contribution of Maillard reactions to the flavor of Jinhua ham. © 2017 Institute of Food Technologists®.

  6. High-throughput screening to identify inhibitors of lysine demethylases.

    Science.gov (United States)

    Gale, Molly; Yan, Qin

    2015-01-01

    Lysine demethylases (KDMs) are epigenetic regulators whose dysfunction is implicated in the pathology of many human diseases including various types of cancer, inflammation and X-linked intellectual disability. Particular demethylases have been identified as promising therapeutic targets, and tremendous efforts are being devoted toward developing suitable small-molecule inhibitors for clinical and research use. Several High-throughput screening strategies have been developed to screen for small-molecule inhibitors of KDMs, each with advantages and disadvantages in terms of time, cost, effort, reliability and sensitivity. In this Special Report, we review and evaluate the High-throughput screening methods utilized for discovery of novel small-molecule KDM inhibitors.

  7. Modelling of Fed-batch Fermentation Process with Droppings for L-lysine Production

    Directory of Open Access Journals (Sweden)

    Velitchka Ivanova

    2006-04-01

    Full Text Available The aim of the article is the development of dynamic unstructured model of L-lysine fed-batch fermentation process with droppings. This approach includes the following procedures: description of the process by generalized stoichiometric equations; preliminary data processing; identification of the specific rates (growth rate (mu , substrate utilization rate (nu, production rate (rho; establishment and optimization of the dynamic model of the process; simulation researches.

  8. Lysine acetyltransferase GCN5b interacts with AP2 factors and is required for Toxoplasma gondii proliferation.

    Directory of Open Access Journals (Sweden)

    Jiachen Wang

    2014-01-01

    Full Text Available Histone acetylation has been linked to developmental changes in gene expression and is a validated drug target of apicomplexan parasites, but little is known about the roles of individual histone modifying enzymes and how they are recruited to target genes. The protozoan parasite Toxoplasma gondii (phylum Apicomplexa is unusual among invertebrates in possessing two GCN5-family lysine acetyltransferases (KATs. While GCN5a is required for gene expression in response to alkaline stress, this KAT is dispensable for parasite proliferation in normal culture conditions. In contrast, GCN5b cannot be disrupted, suggesting it is essential for Toxoplasma viability. To further explore the function of GCN5b, we generated clonal parasites expressing an inducible HA-tagged dominant-negative form of GCN5b containing a point mutation that ablates enzymatic activity (E703G. Stabilization of this dominant-negative GCN5b was mediated through ligand-binding to a destabilization domain (dd fused to the protein. Induced accumulation of the ddHAGCN5b(E703G protein led to a rapid arrest in parasite replication. Growth arrest was accompanied by a decrease in histone H3 acetylation at specific lysine residues as well as reduced expression of GCN5b target genes in GCN5b(E703G parasites, which were identified using chromatin immunoprecipitation coupled with microarray hybridization (ChIP-chip. Proteomics studies revealed that GCN5b interacts with AP2-domain proteins, apicomplexan plant-like transcription factors, as well as a "core complex" that includes the co-activator ADA2-A, TFIID subunits, LEO1 polymerase-associated factor (Paf1 subunit, and RRM proteins. The dominant-negative phenotype of ddHAGCN5b(E703G parasites, considered with the proteomics and ChIP-chip data, indicate that GCN5b plays a central role in transcriptional and chromatin remodeling complexes. We conclude that GCN5b has a non-redundant and indispensable role in regulating gene expression required

  9. Reduced Histone H3 Lysine 9 Methylation Contributes to the Pathogenesis of Latent Autoimmune Diabetes in Adults via Regulation of SUV39H2 and KDM4C

    OpenAIRE

    Liu, Xi-yu; Li, Hong

    2017-01-01

    Aims. Latent autoimmune diabetes in adults (LADA) is an autoimmune disease of which the mechanism is not clear. Emerging evidence suggests that histone methylation contributes to autoimmunity. Methods. Blood CD4+ T lymphocytes from 26 LADA patients and 26 healthy controls were isolated to detect histone H3 lysine 4 and H3 lysine 9 methylation status. Results. Reduced global H3 lysine 9 methylation was observed in LADA patients’ CD4+ T lymphocytes, compared to healthy controls (P < 0.05). H3 l...

  10. Regulating Drug Release Behavior and Kinetics from Matrix Tablets Based on Fine Particle-Sized Ethyl Cellulose Ether Derivatives: An In Vitro and In Vivo Evaluation

    Directory of Open Access Journals (Sweden)

    Kifayat Ullah Shah

    2012-01-01

    Full Text Available The design and fabrication of sustained/controlled release dosage forms, employing new excipients capable of extending/controlling the release of drugs from the dosage forms over prolonged periods, has worked well in achieving optimally enhanced therapeutic levels of the drugs. In this sense, the objective of this study was to investigate the suitability of selected cellulose ether derivatives for use in direct compression (DC and as efficient drug release controlling agents. Controlled release matrix tablets of ciprofloxacin were prepared at different drug-to-polymer (D : P ratios by direct compression using a fine particle sized ethylcellulose ether derivative (ETHOCEL Standard Premium 7FP as rate controlling polymer. The tablets obtained were evaluated for various physico-chemical characteristics and in-vitro drug release studies were conducted in phosphate buffer (pH 7.4 using PharmaTest dissolution apparatus at constant temperature of 37∘C±0.1. Similarity factor 2 was employed to the release profiles of test formulations and were compared with marketed ciprofloxacin conventional tablets. Drug release mechanism and the kinetics involved were investigated by fitting the release profile data to various kinetic models. It was found that with increasing the proportion of ethylcellulose ether derivative in the matrix, the drug release was significantly extended up to 24 hours. The tablets exhibited zero order or nearly zero order drug transport mechanism. In vivo drug release performance of the developed controlled release tablets and reference conventional tablets containing ciprofloxacin were determined in rabbit serum according to randomized two-way crossover study design using High Performance Liquid Chromatography. Several bioavailability parameters of both the test tablets and conventional tablets including max, max and AUC0- were compared which showed an optimized max and max (<0.05. A good correlation was obtained between in vitro

  11. Structural Characterization of Amadori Rearrangement Product of Glucosylated Nα-Acetyl-Lysine by Nuclear Magnetic Resonance Spectroscopy

    Directory of Open Access Journals (Sweden)

    Chuanjiang Li

    2014-01-01

    Full Text Available Maillard reaction is a nonenzymatic reaction between reducing sugars and free amino acid moieties, which is known as one of the most important modifications in food science. It is essential to characterize the structure of Amadori rearrangement products (ARPs formed in the early stage of Maillard reaction. In the present study, the Nα-acetyl-lysine-glucose model had been successfully set up to produce ARP, Nα-acetyl-lysine-glucose. After HPLC purification, ARP had been identified by ESI-MS with intense [M+H]+ ion at 351 m/z and the purity of ARP was confirmed to be over 90% by the relative intensity of [M+H]+ ion. Further structural characterization of the ARP was accomplished by using nuclear magnetic resonance (NMR spectroscopy, including 1D 1H NMR and 13C NMR, the distortionless enhancement by polarization transfer (DEPT-135 and 2D 1H-1H and 13C-1H correlation spectroscopy (COSY and 2D nuclear overhauser enhancement spectroscopy (NOESY. The complexity of 1D 1H NMR and 13C NMR was observed due to the presence of isomers in glucose moiety of ARP. However, DEPT-135 and 2D NMR techniques provided more structural information to assign the 1H and 13C resonances of ARP. 2D NOESY had successfully confirmed the glycosylated site between 10-N in Nα-acetyl-lysine and 7′-C in glucose.

  12. O-Methylisourea Can React with the α-Amino Group of Lysine: Implications for the Analysis of Reactive Lysine.

    Science.gov (United States)

    Hulshof, Tetske G; Rutherfurd, Shane M; Sforza, Stefano; Bikker, Paul; van der Poel, Antonius F B; Hendriks, Wouter H

    2017-02-01

    The specificity of O-methylisourea (OMIU) to bind to the ε-amino group of Lys, an important supposition for the OMIU-reactive Lys analysis of foods, feeds, ingredients, and digesta, was investigated. Crystalline l-Lys incubated under standard conditions with OMIU resulted in low homoarginine recoveries. The reaction of OMIU with the α-amino group of Lys was confirmed by MS analysis, with double derivatized Lys being identified. None of the changes in reaction conditions (OMIU pH, OMIU to Lys ratio, and reaction time) with crystalline l-Lys resulted in 100% recovery of homoarginine. The average free Lys content in ileal digesta of growing pigs and broilers was found to be 13% of total Lys, which could result in a significant underestimation of the reactive Lys content. The reaction of OMIU with α-amino groups may necessitate analysis of free Lys to accurately quantify reactive lysine in samples containing a large proportion of Lys with a free α-amino group.

  13. Study on the biological half-life and organ-distribution of tritiated lysine-vasopressin in Brattleboro rats

    International Nuclear Information System (INIS)

    Laczi, F.; Laszlo, F.A.; Keri, Gy.; Teplan, I.

    1980-01-01

    The biological half-life and organ-distribution of tritiated lysine-vasopressin were determined in R-Amsterdam rats, and in homozygous and heterozygous Brattleboro rats with hereditary central diabetes insipidus. It was found that the biological half-life of the tritiated lysin-vasopressin in the Brattleboro rats did not differ significantly from that found in the R-Amsterdam rats. The highest radioactivities were observed in the neuro- and adenohypophyses and in the kidneys of both the R-Amsterdam and the Brattleboro rats. The accumulation of tritiated LVP was higher in the small intestine of the Brattleboro rats than in that of the R-Amsterdam animals. The results have led to the conclusion that the accelerated elimination of vasopressin and its pathologic organ-accumulation are probably not involved in the water metabolism disturbance of Brattleboro rats with hereditary hypothalamic diabetes insipidus. (author)

  14. Intravenous lysine clonixinate for the acute treatment of severe migraine attacks: a double-blind, randomized, placebo-controlled study.

    Science.gov (United States)

    Krymchantowski, Abouch Valenty; Silva, Marcus Tulius T

    2003-09-01

    Several nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to be effective in the treatment of migraine. However, few commercially available NSAIDs can be administered IV. Lysine clonixinate (LC), an NSAID derived from nicotinic acid, has been proved effective in various algesic syndromes (eg, renal colic, muscular pain, nerve compression, odontalgia). The oral formulation of LC has been shown to be effective in the treatment of migraine of moderate severity. The aim of this study was to assess the efficacy and tolerability of the IV formulation of LC in the treatment of severe migraine. This double-blind, randomized, placebo-controlled, prospective study enrolled patients with severe migraine (without aura) as defined by the criteria of the International Headache Society. When patients presented to a neurology hospital with an outpatient headache unit (Instituto de Neurologia Deolindo Couto, Rio de Janeiro, Brazil) with a severe migraine attack that had lasted <4 hours, they were randomized to 1 of 2 groups (IV placebo [25 mL of 0.9% saline] or IV LC [21 mL of 0.9% saline plus 4 mL of LC 200 mg]). Headache intensity and adverse effects (AEs) were assessed before (0 minute) and 30, 60, and 90 minutes after study drug administration. Rescue medication was available 2 hours after study drug administration, and its use was compared between groups. Thirty-two patients (23 women, 9 men; mean [SD] age, 32 [2] years; range, 18-58 years) entered the study. Twenty-nine patients (21 women, 8 men; mean [SD] age, 32 [2] years; range, 18-56 years) completed the study. Three patients (all in the placebo group) did not complete the study (1 patient was unable to rate the pain severity after drug administration and 2 patients refused IV drug administration). Among study completers, 17 patients received LC and 12 placebo. At 30 minutes, 1 patient (8.3%) in the placebo group and 5 patients (29.4%) in the LC group were pain free; the between-group difference was not

  15. Intravenous lysine clonixinate for the acute treatment of severe migraine attacks: a double-blind, randomized, placebo-controlled study☆

    Science.gov (United States)

    Krymchantowski, Abouch Valenty; Silva, Marcus Tulius T

    2003-01-01

    Background Several nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to be effective in the treatment of migraine. However, few commercially available NSAIDs can be administered IV. Lysine clonixinate (LC), an NSAID derived from nicotinic acid, has been proved effective in various algesic syndromes (eg, renal colic, muscular pain, nerve compression, odontalgia). The oral formulation of LC has been shown to be effective in the treatment of migraine of moderate severity. Objective The aim of this study was to assess the efficacy and tolerability of the IV formulation of LC in the treatment of severe migraine. Methods This double-blind, randomized, placebo-controlled, prospective study enrolled patients with severe migraine (without aura) as defined by the criteria of the International Headache Society. When patients presented to a neurology hospital with an outpatient headache unit (Instituto de Neurologia Deolindo Couto, Rio de Janeiro, Brazil) with a severe migraine attack that had lasted <4 hours, they were randomized to 1 of 2 groups (IV placebo [25 mL of 0.9% saline] or IV LC [21 mL of 0.9% saline plus 4 mL of LC 200 mg]). Headache intensity and adverse effects (AEs) were assessed before (0 minute) and 30, 60, and 90 minutes after study drug administration. Rescue medication was available 2 hours after study drug administration, and its use was compared between groups. Results Thirty-two patients (23 women, 9 men; mean [SD] age, 32 [2] years; range, 18–58 years) entered the study. Twenty-nine patients (21 women, 8 men; mean [SD] age, 32 [2] years; range, 18–56 years) completed the study. Three patients (all in the placebo group) did not complete the study (1 patient was unable to rate the pain severity after drug administration and 2 patients refused IV drug administration). Among study completers, 17 patients received LC and 12 placebo. At 30 minutes, 1 patient (8.3%) in the placebo group and 5 patients (29.4%) in the LC group were pain free

  16. Soft-sensing Modeling Based on MLS-SVM Inversion for L-lysine Fermentation Processes

    Directory of Open Access Journals (Sweden)

    Bo Wang

    2015-06-01

    Full Text Available A modeling approach 63 based on multiple output variables least squares support vector machine (MLS-SVM inversion is presented by a combination of inverse system and support vector machine theory. Firstly, a dynamic system model is developed based on material balance relation of a fed-batch fermentation process, with which it is analyzed whether an inverse system exists or not, and into which characteristic information of a fermentation process is introduced to set up an extended inversion model. Secondly, an initial extended inversion model is developed off-line by the use of the fitting capacity of MLS-SVM; on-line correction is made by the use of a differential evolution (DE algorithm on the basis of deviation information. Finally, a combined pseudo-linear system is formed by means of a serial connection of a corrected extended inversion model behind the L-lysine fermentation processes; thereby crucial biochemical parameters of a fermentation process could be predicted on-line. The simulation experiment shows that this soft-sensing modeling method features very high prediction precision and can predict crucial biochemical parameters of L-lysine fermentation process very well.

  17. Low cytotoxic tissue adhesive based on oxidized dextran and epsilon-poly-L-lysine.

    Science.gov (United States)

    Hyon, Suong-Hyu; Nakajima, Naoki; Sugai, Hajime; Matsumura, Kazuaki

    2014-08-01

    A novel adhesive hydrogel consisting of dextran and epsilon-poly(L-lysine) (dextran-PL) with multiple biomedical applications was developed. Periodate oxidation in aqueous media almost stoichiometrically introduces aldehyde groups in dextran molecules, and aldehyde dextran can react with the primary amino groups in epsilon-PL (ɛ-PL) at neutral pH to form a hydrogel. The gelation time of the hydrogel can be easily controlled by the extent of oxidation in dextran and of the acylation in ɛ-PL by anhydrides. The shear adhesion strength of dextran-PL was 10 times higher than that of fibrin glue, when wet collagen sheets were selected as test specimens. The cytotoxicity of aldehyde dextran and ɛ-PL were 1000 times lower than that of glutaraldehyde and poly(allylamine). The considerably low cytotoxicity of aldehyde dextran could be ascribed to its low reactivity with amine species when compared with glutaraldehyde. In contrast, a high reactivity of amino groups in ɛ-PL was observed when compared with glycine, L-lysine, and gelatin, which could be explained by their poor dissociation at neutral pH, thus leading to low cytotoxicity. © 2013 Wiley Periodicals, Inc.

  18. Metabolic transit of N(ε)-carboxymethyl-lysine after consumption of AGEs from bread crust.

    Science.gov (United States)

    Roncero-Ramos, Irene; Delgado-Andrade, Cristina; Tessier, Frédéric J; Niquet-Léridon, Céline; Strauch, Christopher; Monnier, Vincent M; Navarro, María Pilar

    2013-07-01

    Our aim was to investigate carboxymethyl-lysine (CML) intake and excretion after feeding rats with diets containing advanced glycation end-products (AGEs) from bread crust (BC) or its soluble or insoluble fractions, and to identify the factors responsible for the effects observed. CML in serum and different tissues was measured to detect possible accumulations. For 88 days, weanling rats were fed with either a control diet or one containing BC, or its soluble low molecular weight (LMW), soluble high molecular weight (HMW) or insoluble fractions. In the last week of the assay, faeces and urine were collected daily and stored as a 1 week pool. After sacrifice, blood was drawn to obtain serum and some organs were removed. CML analysis was performed by HPLC/MS/MS in diets, faeces, urines, serum and tissues. Faecal excretion of CML was strongly influenced by dietary CML levels and represents the major route of excretion (i.e. 33.2%). However, the urinary elimination of CML was probably limited or saturated, especially when more complex compounds were present in the diet. BC consumption increased CML in the cardiac tissue (170 ± 18 vs. 97 ± 3 μmol per mol lysine for BC and control groups), which correlated with the CML intake. The levels of this AGE in bone were unaffected by the dietary treatment, but in tail tendons CML was greatly increased in the animals that consumed the BC diet (102 ± 13 vs. 51 ± 8 μmol per mol lysine for BC and control groups, P = 0.006), which was associated with the intake of soluble LMW compounds present in BC. Despite the CML accumulation detected in different tissues, serum levels of protein-bound CML were unchanged, indicating the importance of measuring the free CML in this fluid as a real index of dietary CML.

  19. Removal U(VI) from artificial seawater using facilely and covalently grafted polyacrylonitrile fibers with lysine

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wenting; Liu, Qi; Liu, Jingyuan; Zhang, Hongsen; Li, Rumin; Li, Zhanshuang; Jing, Xiaoyan [Key Laboratory of Superlight Material and Surface Technology, Ministry of Education, Harbin Engineering University, Harbin 150001 (China); Wang, Jun, E-mail: zhqw1888@sohu.com [Key Laboratory of Superlight Material and Surface Technology, Ministry of Education, Harbin Engineering University, Harbin 150001 (China); Institute of Advanced Marine Materials, Harbin Engineering University, 150001 (China)

    2017-05-01

    Highlights: • Novel lysine modified fibrous adsorbents were prepared using a facile and green method. • PAN-Lys exhibited high adsorption activity and fast adsorption rate. • PAN-Lys significantly remove U(VI) from simulated seawater. - Abstract: Polyacrylonitrile fibers (PANF) covalently modified with lysine (PAN-Lys) was facilely synthesized and carefully characterized. The critical factors affecting U(VI) adsorption from aqueous solution were exploited, such as initial pH, contact time, concentration and temperature. The adsorption process is strongly dependent on solution pH. With excellent adsorption capacity and high affinity toward U(VI), the process for U(VI) is extremely rapid and the equilibrium can be reached within 20 min. The thermodynamics and kinetics were strictly evaluated. In addition, the hypothetical adsorption mechanisms were proposed. Moreover, the adsorption behavior at low concentrations (3–30 μg L{sup −1}) in simulated seawater was also investigated. Therefore, PAN-Lys can be potentially utilized for the efficient removal of U(VI) from seawater.

  20. Nutritional plans of digestible lysine for growing-finishing gilts

    Directory of Open Access Journals (Sweden)

    Gabriel Cipriano Rocha

    2014-09-01

    Full Text Available This experiment was conducted to evaluate nutritional plans of digestible lysine (DLys for growing-finishing gilts. Eighty gilts with 63 days of age and an initial weight of 24.2±1.52 kg were distributed in a completely randomized block design, with five nutritional plans of DLys (9-8-7, 10-9-8, 11-10-9, 12-11-10, and 13-12-11 g/kg, from 63 to 103, 104 to 133, and 134 to 153 days of age, respectively and eight replicates. Pigs were housed in pairs and fed their respective diets ad libitum throughout the experimental period (90 days. To monitor the animal development along the experiment at 103 and 133 days, gilts were weighed and subjected to analysis of ultrasound for evaluation of loin depth (longissimus dorsi and backfat thickness. At the end of the experiment (153 days of age the animals were weighed, and after slaughter carcasses were evaluated individually using a typifying pistol to evaluate the percentage and the content of carcass meat, loin depth and backfat thickness. From 63 to 133 days, there was no effect of the nutritional plans on daily feed intake, performance, or backfat thickness; however the loin depth was greater in the gilts that received plans with high levels of DLys (12-11; 13-12 g/kg compared with the plan with the lowest level (8-7 g/kg. For the entire period (63 to 153 days, no influence of the nutritional plans was observed on the daily feed intake, performance variables, or carcass characteristics. A nutritional plan containing 9-8-7 g/kg of digestible lysine fed from 63 to 103, 104 to 133 and 134 to 153 days, respectively, meets the requirements for performance and carcass characteristics of growing-finishing gilts.

  1. Transcriptome and Gene Ontology (GO) Enrichment Analysis Reveals Genes Involved in Biotin Metabolism That Affect L-Lysine Production in Corynebacterium glutamicum.

    Science.gov (United States)

    Kim, Hong-Il; Kim, Jong-Hyeon; Park, Young-Jin

    2016-03-09

    Corynebacterium glutamicum is widely used for amino acid production. In the present study, 543 genes showed a significant change in their mRNA expression levels in L-lysine-producing C. glutamicum ATCC21300 than that in the wild-type C. glutamicum ATCC13032. Among these 543 differentially expressed genes (DEGs), 28 genes were up- or downregulated. In addition, 454 DEGs were functionally enriched and categorized based on BLAST sequence homologies and gene ontology (GO) annotations using the Blast2GO software. Interestingly, NCgl0071 (bioB, encoding biotin synthase) was expressed at levels ~20-fold higher in the L-lysine-producing ATCC21300 strain than that in the wild-type ATCC13032 strain. Five other genes involved in biotin metabolism or transport--NCgl2515 (bioA, encoding adenosylmethionine-8-amino-7-oxononanoate aminotransferase), NCgl2516 (bioD, encoding dithiobiotin synthetase), NCgl1883, NCgl1884, and NCgl1885--were also expressed at significantly higher levels in the L-lysine-producing ATCC21300 strain than that in the wild-type ATCC13032 strain, which we determined using both next-generation RNA sequencing and quantitative real-time PCR analysis. When we disrupted the bioB gene in C. glutamicum ATCC21300, L-lysine production decreased by approximately 76%, and the three genes involved in biotin transport (NCgl1883, NCgl1884, and NCgl1885) were significantly downregulated. These results will be helpful to improve our understanding of C. glutamicum for industrial amino acid production.

  2. Metabolism of designer drugs of abuse.

    Science.gov (United States)

    Staack, Roland F; Maurer, Hans H

    2005-06-01

    Abuse of designer drugs is widespread among young people, especially in the so-called "dance club scene" or "rave scene", worldwide. Severe and even fatal poisonings have been attributed to the consumption of such drugs of abuse. However, in contrast to new medicaments, which are extensively studied in controlled clinical studies concerning metabolism, including cytochrome P450 isoenzyme differentiation, and further pharmacokinetics, designer drugs are consumed without any safety testing. This paper reviews the metabolism of new designer drugs of abuse that have emerged on the black market during the last years. Para-methoxyamphetamine (PMA), para-methoxymethamphetamine (PMMA) and 4-methylthioamphetamine (4-MTA), were taken into consideration as new "classical" amphetamine-derived designer drugs. Furthermore, N-benzylpiperazine (BZP), 1-(3, 4-methylenedioxybenzyl)piperazine (MDBP), 1-(3-trifluoromethylphenyl)piperazine (TFMPP), 1-(3-chlorophenyl)piperazine (mCPP) and 1-(4-methoxyphenyl)piperazine (MeOPP) were taken into consideration as derivatives of the class of piperazine-derived designer drugs, as well as alpha-pyr-rolidinopropiophenone (PPP), 4'-methoxy-alpha-pyrrolidinopropiophenone (MOPPP), 3', 4'-methylenedioxy-alpha-pyrrolidino-propiophenone (MDPPP), 4'-methyl-alpha-pyrrolidinopropiophenone (MPPP), and 4'-methyl-alpha-pyrrolidinoexanophenone (MPHP) as derivatives of the class of alpha-pyrrolidinophenone-derived designer drugs. Papers describing identification of in vivo or in vitro human or animal metabolites and cytochrome P450 isoenzyme dependent metabolism have been considered and summarized.

  3. Characterization of dapB, a gene required by Pseudomonas syringae pv. tabaci BR2.024 for lysine and tabtoxinine-beta-lactam biosynthesis.

    Science.gov (United States)

    Liu, L; Shaw, P D

    1997-01-01

    The dapB gene, which encodes L-2,3-dihydrodipicolinate reductase, the second enzyme of the lysine branch of the aspartic amino acid family, was cloned and sequenced from a tabtoxin-producing bacterium, Pseudomonas syringae pv. tabaci BR2.024. The deduced amino acid sequence shared 60 to 90% identity to known dapB gene products from gram-negative bacteria and 19 to 21% identity to the dapB products from gram-positive bacteria. The consensus sequence for the NAD(P)H binding site [(V/I)(A/G)(V/I)XGXXGXXG)] and the proposed substrate binding site (HHRHK) were conserved in the polypeptide. A BR2.024 dapB mutant is a diaminopimelate auxotroph and tabtoxin negative. The addition of a mixture of L-,L-, D,D-, and meso-diaminopimelate to defined media restored growth but not tabtoxin production. Cloned DNA fragments containing the parental dapB gene restored the ability to grow in defined media and tabtoxin production to the dapB mutant. These results indicate that the dapB gene is required for both lysine and tabtoxin biosynthesis, thus providing the first genetic evidence that the biosynthesis of tabtoxin proceeds in part along the lysine biosynthetic pathway. These data also suggest that L-2,3,4,5-tetrahydrodipicolinate is a common intermediate for both lysine and tabtoxin biosynthesis. PMID:8990304

  4. Exigência de lisina para poedeiras semipesadas durante o pico de postura Lysine requeriment of semi-heavy laying hens during the peak of egg production

    Directory of Open Access Journals (Sweden)

    José Jordão Filho

    2006-08-01

    Full Text Available Objetivando determinar as exigências nutricionais de lisina para 252 poedeiras semipesadas, foi conduzido um experimento em delineamento inteiramente ao acaso, com sete tratamentos, constituídos de seis repetições de seis aves. As dietas, isoprotéicas (17,1% de PB e isocalóricas (2.800 kcal/kg-EM, foram formuladas para atender às exigências das aves em todos os nutrientes, exceto lisina, que foi suplementada com L-lisina • HCl (78,4% de lisina, resultando nos seguintes níveis: 0,79; 0,83; 0,87; 0,91; 0,95; 0,99 e 1,03% de lisina total. As características de desempenho foram avaliadas no período de 30 a 46 semanas de idade, que corresponde ao pico de postura. Foi observado efeito quadrático dos níveis de lisina sobre a produção, o peso e a conversão alimentar por dúzia de ovos. As exigências de lisina total foram de 0,92; 0,91 e 0,90%, que correspondem, respectivamente, a 0,84; 0,83 e 0,82% de lisina digestível. Recomenda-se 0,92 ou 0,84%, ou 996 ou 910 mg, de lisina total e digestível/ave/dia para poedeiras semipesadas durante o pico de postura.An experiment was carried out as a completely randomized design, with seven treatments, and six replicates of six birds to determine the lysine nutritional requeriments for 252 semi-heavy laying hens. The diets were formulated to be isonitrogenous (17.1%CP and isoenergy (2,800 kcal/kg-ME and to meet all bird nutrient requeriments, with the exception of lysine, that was supplemented with L-lysine • HCl (78.4% of lysine and resulted in the following levels: 0.79, 0.83, 0.87, 0.91, 0.95, 0.99, and 1.03% of total lysine. The performance variables were evaluated from 30 to 46 weeks of age, that correspond to the peak of egg production in commercial hens. Quadract effect of treatments on egg production, egg weight and egg dozen:feed ratio was observed. The total lysine requeriments were of 0.92, 0.91, and 0.90, that was correspondent to the estimate of 0.84, 0.83, and 0.82% of digestible

  5. Enhancement of bioavailability by formulating rhEPO ionic complex with lysine into PEG-PLA micelle

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Yanan; Sun, Fengying; Wang, Dan; Zhang, Renyu [Jilin University, College of Life Science (China); Dou, Changlin; Liu, Wanhui; Sun, Kaoxiang, E-mail: sunkx@ytu.edu.cn [Yantai University, School of Pharmacy (China); Li, Youxin, E-mail: liyouxin@jlu.edu.cn [Jilin University, College of Life Science (China)

    2013-10-15

    A composite micelle of ionic complex encapsulated into poly(ethylene glycol)-poly(d,l-lactide) (PEG-PLA) di-block copolymeric micelles was used for protein drug delivery to improve its pharmacokinetic performance. In this study, recombinant human erythropoietin (rhEPO, as a model protein) was formulated with lysine into composite micelles at a diameter of 71.5 nm with narrow polydispersity indices (PDIs < 0.3). Only a trace amount of protein was in aggregate form. The zeta potential of the spherical micelles was ranging from -0.54 to 1.39 mv, and encapsulation efficiency is high (80 %). The stability of rhEPO was improved significantly in composite micelles in vitro. Pharmacokinetic studies in rats showed significant, enhanced plasma retention of the composite micelles in comparison with native rhEPO. Areas under curve (AUCs) of the rhEPO released from the composite micelles were 4.5- and 2.3-folds higher than those of the native rhEPO and rhEPO-loaded PEG-PLA micelle, respectively. In addition, the composite micelles exhibited good biocompatibility using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay with human embryonic kidney (HEK293T) cells. All these features are preferable for utilizing the composite micelles as a novel protein delivery system.

  6. Enhancement of bioavailability by formulating rhEPO ionic complex with lysine into PEG-PLA micelle

    Science.gov (United States)

    Shi, Yanan; Sun, Fengying; Wang, Dan; Zhang, Renyu; Dou, Changlin; Liu, Wanhui; Sun, Kaoxiang; Li, Youxin

    2013-10-01

    A composite micelle of ionic complex encapsulated into poly(ethylene glycol)-poly( d, l-lactide) (PEG-PLA) di-block copolymeric micelles was used for protein drug delivery to improve its pharmacokinetic performance. In this study, recombinant human erythropoietin (rhEPO, as a model protein) was formulated with lysine into composite micelles at a diameter of 71.5 nm with narrow polydispersity indices (PDIs protein was in aggregate form. The zeta potential of the spherical micelles was ranging from -0.54 to 1.39 mv, and encapsulation efficiency is high (80 %). The stability of rhEPO was improved significantly in composite micelles in vitro. Pharmacokinetic studies in rats showed significant, enhanced plasma retention of the composite micelles in comparison with native rhEPO. Areas under curve (AUCs) of the rhEPO released from the composite micelles were 4.5- and 2.3-folds higher than those of the native rhEPO and rhEPO-loaded PEG-PLA micelle, respectively. In addition, the composite micelles exhibited good biocompatibility using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay with human embryonic kidney (HEK293T) cells. All these features are preferable for utilizing the composite micelles as a novel protein delivery system.

  7. Lysine-specific demethylase 1 (LSD1) destabilizes p62 and inhibits autophagy in gynecologic malignancies.

    Science.gov (United States)

    Chao, Angel; Lin, Chiao-Yun; Chao, An-Ning; Tsai, Chia-Lung; Chen, Ming-Yu; Lee, Li-Yu; Chang, Ting-Chang; Wang, Tzu-Hao; Lai, Chyong-Huey; Wang, Hsin-Shih

    2017-09-26

    Lysine-specific demethylase 1 (LSD1) - also known as KDM1A - is the first identified histone demethylase. LSD1 is highly expressed in numerous human malignancies and has recently emerged as a target for anticancer drugs. Owing to the presence of several functional domains, we speculated that LSD1 could have additional functions other than histone demethylation. P62 - also termed sequestasome 1 (SQSTM1) - plays a key role in malignant transformation, apoptosis, and autophagy. Here, we show that a high LSD1 expression promotes tumorigenesis in gynecologic malignancies. Notably, LSD1 inhibition with either siRNA or pharmacological agents activates autophagy. Mechanistically, LSD1 decreases p62 protein stability in a demethylation-independent manner. Inhibition of LSD1 reduces both tumor growth and p62 protein degradation in vivo . The combination of LSD1 inhibition and p62 knockdown exerts additive anticancer effects. We conclude that LSD1 destabilizes p62 and inhibits autophagy in gynecologic cancers. LSD1 inhibition reduces malignant cell growth and activates autophagy. The combinations of LSD1 inhibition and autophagy blockade display additive inhibitory effect on cancer cell viability. A better understanding of the role played by p62 will shed more light on the anticancer effects of LSD1 inhibitors.

  8. Lysine deacetylases are produced in pancreatic beta cells and are differentially regulated by proinflammatory cytokines

    DEFF Research Database (Denmark)

    Lundh, M; Christensen, D P; Rasmussen, D N

    2010-01-01

    Cytokine-induced beta cell toxicity is abrogated by non-selective inhibitors of lysine deacetylases (KDACs). The KDAC family consists of 11 members, namely histone deacetylases HDAC1 to HDAC11, but it is not known which KDAC members play a role in cytokine-mediated beta cell death. The aim...

  9. Potential differentiation of islet-like cells from pregnant cow-derived placental stem cells.

    Science.gov (United States)

    Peng, Shao-Yu; Chou, Chien-Wen; Kuo, Yu-Hsuan; Shen, Perng-Chih; Shaw, S W Steven

    2017-06-01

    Type 1 diabetes is an autoimmune disease that destroys islet cells and results in insufficient insulin secretion by pancreatic β-cells. Islet transplantation from donors is an approach used for treating patients with diabetes; however, this therapy is difficult to implement because of the lack of donors. Nevertheless, several stem cells have the potential to differentiate from islet-like cells and enable insulin secretion for treating diabetes in animal models. For example, placenta is considered a waste material and can be harvested noninvasively during delivery without ethical or moral concerns. To date, the differentiation of islet-like cells from cow-derived placental stem cells (CPSCs) has yet to be demonstrated. The investigation of potential differentiation of islet-like cells from CPSCs was conducted by supplementation with nicotinamide, exendin-4, glucose, and poly-d-lysine and was detected through reverse transcription polymerase chain reaction, dithizone staining, and immunocytochemical methods. Our results indicated that CPSCs are established and express mesenchymal stem cell surface antigen markers, such as CD73, CD166, β-integrin, and Oct-4, but not hematopoietic stem cell surface antigen markers, such as CD45. After induction, the CPSCs successfully differentiated into islet-like cells. The CPSC-derived islet-like cells expressed islet cell development-related genes, such as insulin, glucagon, pax-4, Nkx6.1, pax-6, and Fox. Moreover, CPSC-derived islet-like cells can be stained with zinc ions, which are widely distributed in the islet cells and enable insulin secretion. Altogether, islet-like cells have the potential to be differentiated from CPSCs without gene manipulation, and can be used in diabetic animal models in the future for preclinical and drug testing trial investigations. Copyright © 2017. Published by Elsevier B.V.

  10. Lysine clonixinate vs naproxen sodium for the acute treatment of migraine: a double-blind, randomized, crossover study.

    Science.gov (United States)

    Krymchantowski, Abouch Valenty; Peixoto, Patricia; Higashi, Rafael; Silva, Ariovaldo; Schutz, Vivian

    2005-12-14

    The process of inflammation is crucial in migraine, and several nonsteroidal anti-inflammatory drugs (NSAIDs) are effective in the treatment of migraine attacks. Despite their efficacy, the routine use of NSAIDs is limited by side effects as well as incomplete efficacy in some patients. Among the available options, lysine clonixinate (LC) and naproxen sodium (NS) have proved effective in migraine. The aim of this study was to compare the efficacy and tolerability of oral formulations of LC and NS in the treatment of moderate or severe migraine attacks, with a double-blind, crossover design. Seventy subjects (62 women, 8 men) between ages 18 and 71 years (mean age, 41) with migraine according to the criteria of the International Headache Society were prospectively enrolled. The patients were randomized into 2 groups and each participant treated 2 migraine attacks. Group 1 treated the first attack with LC and the second attack with NS. Group 2 treated 2 attacks in a counterbalanced order. Doses were 250 mg of LC or 550 mg of NS, which were encapsulated for equal appearance. Headache intensity, nausea, photophobia, and side effects were evaluated at baseline, 1 hour, and 2 hours after drug administration. Rescue drugs were allowed after 2 hours for those who didn't respond, and this was also compared between groups. Sixty patients (54 women, 6 men) completed the study. At 1 hour, 13.6% patients who used LC were pain-free compared with 11.9% who used NS (P = .78). At 2 hours, 35.6% patients who took LC and 32.2% who took NS were pain-free (P = .69). At baseline, 52.5% of the patients randomized to group 1 reported nausea, compared with 33.9% in group 2, and both drugs eliminated nausea: At both 1 hour and 2 hours, nausea diminished significantly for those taking LC, but only after 2 hours for those who took NS (P < .0001). Both drugs eliminated photophobia at 1 hour and 2 hours; however, LC was superior to NS in reducing photophobia at 2 hours (P = .027). Ten patients

  11. Ab Initio Calculations of Deuterium Isotope Effects on Chemical Shifts of Salt-Bridged Lysines

    DEFF Research Database (Denmark)

    Ullah, Saif; Ishimoto, Takayoshi; Williamson, Mike P.

    2011-01-01

    (D), in ammonium and amines decrease as a counterion or water molecule moves closer to the nitrogen. 1Δ15N(D) and 2Δ1H(D) of the NH3+ groups of lysine residues in the B1 domain of protein G have been calculated using truncated side chains and also determined experimentally by NMR. Comparisons show...

  12. Human 14-3-3 paralogs differences uncovered by cross-talk of phosphorylation and lysine acetylation.

    Directory of Open Access Journals (Sweden)

    Marina Uhart

    Full Text Available The 14-3-3 protein family interacts with more than 700 different proteins in mammals, in part as a result of its specific phospho-serine/phospho-threonine binding activity. Upon binding to 14-3-3, the stability, subcellular localization and/or catalytic activity of the ligands are modified. Seven paralogs are strictly conserved in mammalian species. Although initially thought as redundant, the number of studies showing specialization is growing. We created a protein-protein interaction network for 14-3-3, kinases and their substrates signaling in human cells. We included information of phosphorylation, acetylation and other PTM sites, obtaining a complete representation of the 14-3-3 binding partners and their modifications. Using a computational system approach we found that networks of each 14-3-3 isoform are statistically different. It was remarkable to find that Tyr was the most phosphorylatable amino acid in domains of 14-3-3 epsilon partners. This, together with the over-representation of SH3 and Tyr_Kinase domains, suggest that epsilon could be involved in growth factors receptors signaling pathways particularly. We also found that within zeta's network, the number of acetylated partners (and the number of modify lysines is significantly higher compared with each of the other isoforms. Our results imply previously unreported hidden differences of the 14-3-3 isoforms interaction networks. The phosphoproteome and lysine acetylome within each network revealed post-transcriptional regulation intertwining phosphorylation and lysine acetylation. A global understanding of these networks will contribute to predict what could occur when regulatory circuits become dysfunctional or are modified in response to external stimuli.

  13. Effect of lysine to alanine mutations on the phosphate activation and BPTES inhibition of glutaminase.

    Science.gov (United States)

    McDonald, Charles J; Acheff, Eric; Kennedy, Ryan; Taylor, Lynn; Curthoys, Norman P

    2015-09-01

    The GLS1 gene encodes a mitochondrial glutaminase that is highly expressed in brain, kidney, small intestine and many transformed cells. Recent studies have identified multiple lysine residues in glutaminase that are sites of N-acetylation. Interestingly, these sites are located within either a loop segment that regulates access of glutamine to the active site or the dimer:dimer interface that participates in the phosphate-dependent oligomerization and activation of the enzyme. These two segments also contain the binding sites for bis-2[5-phenylacetamido-1,2,4-thiadiazol-2-yl]ethylsulfide (BPTES), a highly specific and potent uncompetitive inhibitor of this glutaminase. BPTES is also the lead compound for development of novel cancer chemotherapeutic agents. To provide a preliminary assessment of the potential effects of N-acetylation, the corresponding lysine to alanine mutations were constructed in the hGACΔ1 plasmid. The wild type and mutated proteins were purified by Ni(+)-affinity chromatography and their phosphate activation and BPTES inhibition profiles were analyzed. Two of the alanine substitutions in the loop segment (K311A and K328A) and the one in the dimer:dimer interface (K396A) form enzymes that require greater concentrations of phosphate to produce half-maximal activation and exhibit greater sensitivity to BPTES inhibition. By contrast, the K320A mutation results in a glutaminase that exhibits near maximal activity in the absence of phosphate and is not inhibited by BPTES. Thus, lysine N-acetylation may contribute to the acute regulation of glutaminase activity in various tissues and alter the efficacy of BPTES-type inhibitors. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Evaluation of 8-Hydroxyquinoline Derivatives as Hits for Antifungal Drug Design.

    Science.gov (United States)

    Pippi, Bruna; Reginatto, Paula; Machado, Gabriella da Rosa Monte; Bergamo, Vanessa Zafaneli; Lana, Daiane Flores Dalla; Teixeira, Mario Lettieri; Franco, Lucas Lopardi; Alves, Ricardo José; Andrade, Saulo Fernandes; Fuentefria, Alexandre Meneghello

    2017-10-01

    Clioquinol is an 8-hydroxyquinoline derivative that was widely used from the 1950s to 1970s as an oral antiparasitic agent. In 1970, the oral forms were withdrawn from the market due to reports of toxicity, but topical formulations for antifungal treatment remained available. Thus, the purpose of this study was to evaluate the toxicity, anti-Candida and antidermatophyte activity and to determine pharmacodynamic characteristics of clioquinol and other 8-hydroxyquinoline derivatives (8-hydroxy-5-quinolinesulfonic acid and 8-hydroxy-7-iodo-5-quinolinesulfonic acid). Antifungal activity was tested by broth microdilution and the fungicidal or fungistatic effect was checked by a time-kill assay. Permeation and histopathological evaluation were performed in Franz diffusion cells with ear skin of pigs and examined under light microscopy. An HET-CAM test was used to determine the potential irritancy. The three compounds were active against all isolates showing anti-Candida and antidermatophyte activity, with MIC ranges of 0.031-2 μg/ml, 1-512 μg/ml, and 2-1024 μg/ml for clioquinol, 8-hydroxy-5-quinolinesulfonic acid, and 8-hydroxy-7-iodo-5-quinolinesulfonic acid, respectively. All compounds showed fungistatic effect for Candida, 8-hydroxy-5-quinolinesulfonic acid, and 8-hydroxy-7-iodo-5-quinolinesulfonic acid showed a fungicidal effect for M. canis and T. mentagrophytes, and clioquinol showed a fungicidal effect only for T. mentagrophytes. Furthermore, they presented a fungicidal effect depending on the time and concentration. The absence of lesions was observed in histopathological evaluation and no compound was irritating. Moreover, clioquinol and 8-hydroxy-5-quinolinesulfonic acid accumulated in the epithelial tissue, and 8-hydroxy-7-iodo-5-quinolinesulfonic acid had a high degree of permeation. In conclusion, 8-hydroxyquinoline derivatives showed antifungal activity and 8-hydroxy-5-quinolinesulfonic acid demonstrated the potential for antifungal drug design.

  15. Effect of Nitrogen Fertilizers on the Lysine Synthesis in Silo-Maize

    Energy Technology Data Exchange (ETDEWEB)

    Cencelj, J.; Jelenic, Dj. [Institute for the Application of Nuclear Energy in Agriculture, Veterinary Medicine and Forestry, Belgrade, Yugoslavia (Serbia)

    1968-07-01

    In investigations on amino acids of silo-maize, different nitrogen fertilizers were studied to determine their effect on amino acid composition and variation during the growth period. The experiment was carried out with silo-maize, hybrid W 464A, grown on sandy soil, which had not been treated for six years with either fertilizers or manure. Before cultivation phosphorus and potassium fertilizers were applied, and the nitrogen fertilizers, ammonium sulphate, ammonium nitrate, calcium cyanamide and urea, were applied at the most appropriate time of application. The first samples were taken at the time of flowering, the second after flowering, and the third, fourth and fifth in the lactic, wax, and full maturity phases, respectively. The percentages of crude protein of the maize gradually decreased while the nitrogen-free extraction matter increased during this period. The protein content of the maize was highest with sodium nitrate and urea fertilization and lowest when calcium cyanamide was used. Investigations to determine whether or not an increase in crude protein content was correlated with an increased content of lysine have shown that there is a correlation when plants are fertilized with calcium cyanamide. The content of essential amino acids was more satisfactory in plants fertilized with urea than with sodium nitrate. According to the statistical analysis, the best improvement in lysine content was obtained with urea (0.23%), the least satisfactory with calcium cyanamide (0.17%), and PK fertilizers without nitrogen (0.15%). (author)

  16. A comparative study of tranexamic acid and ethamsylate in menorrhagia

    OpenAIRE

    Nita K. Patel; Manish R. Pandya

    2012-01-01

    Background: Menorrhagia interferes with the woman's physical, social, emotional, and/or material quality of life. Antifibrinolytic drugs are effective in decreasing excessive menstrual bleeding. The objective of this study was to compare the effects of tranexamic acid and ethamsylate on quality of life in women with menorrhagia. Methods: The 50 women with menorrhagia were randomised to receive either tranexamic acid or ethamsylate. Twenty five patients were allocated to receive tranexamic aci...

  17. Mesobuthus Venom-Derived Antimicrobial Peptides Possess Intrinsic Multifunctionality and Differential Potential as Drugs

    Directory of Open Access Journals (Sweden)

    Bin Gao

    2018-02-01

    Full Text Available Animal venoms are a mixture of peptides and proteins that serve two basic biological functions: predation and defense against both predators and microbes. Antimicrobial peptides (AMPs are a common component extensively present in various scorpion venoms (herein abbreviated as svAMPs. However, their roles in predation and defense against predators and potential as drugs are poorly understood. Here, we report five new venom peptides with antimicrobial activity from two Mesobuthus scorpion species. These α-helical linear peptides displayed highly bactericidal activity toward all the Gram-positive bacteria used here but differential activity against Gram-negative bacteria and fungi. In addition to the antibiotic activity, these AMPs displayed lethality to houseflies and hemotoxin-like toxicity on mice by causing hemolysis, tissue damage and inducing inflammatory pain. Unlike AMPs from other origins, these venom-derived AMPs seem to be unsuitable as anti-infective drugs due to their high hemolysis and low serum stability. However, MeuTXKβ1, a known two-domain Mesobuthus AMP, is an exception since it exhibits high activity toward antibiotic resistant Staphylococci clinical isolates with low hemolysis and high serum stability. The findings that the classical AMPs play predatory and defensive roles indicate that the multifunctionality of scorpion venom components is an intrinsic feature likely evolved by natural selection from microbes, prey and predators of scorpions. This definitely provides an excellent system in which one can study how a protein adaptively evolves novel functions in a new environment. Meantimes, new strategies are needed to remove the toxicity of svAMPs on eukaryotic cells when they are used as leads for anti-infective drugs.

  18. Proteomic analysis of lysine acetylation sites in rat tissues reveals organ specificity and subcellular patterns

    DEFF Research Database (Denmark)

    Lundby, Alicia; Hansen, Kasper Lage; Weinert, Brian Tate

    2012-01-01

    ,541 proteins and provide the data set as a web-based database. We demonstrate that lysine acetylation displays site-specific sequence motifs that diverge between cellular compartments, with a significant fraction of nuclear sites conforming to the consensus motifs G-AcK and AcK-P. Our data set reveals...

  19. Intracellular Environment-Responsive Stabilization of Polymer Vesicles Formed from Head-Tail Type Polycations Composed of a Polyamidoamine Dendron and Poly(L-lysine

    Directory of Open Access Journals (Sweden)

    Kenji Kono

    2013-09-01

    Full Text Available For the development of effective drug carriers, nanocapsules that respond to micro-environmental changes including a decrease in pH and a reductive environment were prepared by the stabilization of polymer vesicles formed from head-tail type polycations, composed of a polyamidoamine dendron head and a poly(L-lysine tail (PAMAM dendron-PLL, through the introduction of disulfide bonds between the PLL tails. Disulfide bonds were successfully introduced through the reaction of Lys residues in the PAMAM dendron-PLL polymer vesicles with 2-iminothiolane. The stabilization of PAMAM dendron-PLL polymer vesicles was confirmed by dynamic light scattering measurements. In acid-base titration experiments, nanocapsules cross-linked by disulfide bonds had a buffering effect during the cellular uptake process. The PAMAM dendron-PLL nanocapsules were used to incorporate the fluorescent dyes rhodamine 6G and fluorescein as a drug model. Cationic rhodamine 6G was generally not released from the nanocapsules because of the electrostatic barrier of the PLL membrane. However, the nanocapsules were destabilized at high glutathione concentrations corresponding to intracellular concentrations. Rhodamine 6G was immediately released from the nanocapsules because of destabilization upon the cleavage of disulfide bonds. This release of rhodamine 6G from the nanocapsules was also observed in HeLa cells by laser confocal microscopy.

  20. pSuc-Lys: Predict lysine succinylation sites in proteins with PseAAC and ensemble random forest approach.

    Science.gov (United States)

    Jia, Jianhua; Liu, Zi; Xiao, Xuan; Liu, Bingxiang; Chou, Kuo-Chen

    2016-04-07

    Being one type of post-translational modifications (PTMs), protein lysine succinylation is important in regulating varieties of biological processes. It is also involved with some diseases, however. Consequently, from the angles of both basic research and drug development, we are facing a challenging problem: for an uncharacterized protein sequence having many Lys residues therein, which ones can be succinylated, and which ones cannot? To address this problem, we have developed a predictor called pSuc-Lys through (1) incorporating the sequence-coupled information into the general pseudo amino acid composition, (2) balancing out skewed training dataset by random sampling, and (3) constructing an ensemble predictor by fusing a series of individual random forest classifiers. Rigorous cross-validations indicated that it remarkably outperformed the existing methods. A user-friendly web-server for pSuc-Lys has been established at http://www.jci-bioinfo.cn/pSuc-Lys, by which users can easily obtain their desired results without the need to go through the complicated mathematical equations involved. It has not escaped our notice that the formulation and approach presented here can also be used to analyze many other problems in computational proteomics. Copyright © 2016 Elsevier Ltd. All rights reserved.