Avian leukosis virus is a versatile eukaryotic platform for polypeptide display

International Nuclear Information System (INIS)

Khare, Pranay D.; Russell, Stephen J.; Federspiel, Mark J.

2003-01-01

Display technology refers to methods of generating libraries of modularly coded biomolecules and screening them for particular properties. Retroviruses are good candidates to be a eukaryotic viral platform for the display of polypeptides synthesized in eukaryotic cells. Here we demonstrate that avian leukosis virus (ALV) provides an ideal platform for display of nonviral polyaeptides expressed in a eukaryotic cell substrate. Different sizes of polypeptides were genetically fused to the extreme N-terminus of the ALV envelope glycoprotein in an ALV infectious clone containing an alkaline phosphatase reporter gene. The chimeric envelope glycoproteins were efficiently incorporated into virions and were stably displayed on the surface of the virions through multiple virus replication cycles. The foreign polypeptides did not interfere with the attachment and entry functions of the underlying ALV envelope glycoproteins. The displayed polypeptides were fully functional and could efficiently mediate attachment of the recombinant viruses to their respective cognate receptors. This study demonstrates that ALV is an ideal display platform for the generation and selection of libraries of polypeptides where there is a need for expression, folding, and posttranslational modification in the endoplasmic reticulum of eukaryotic cells

Spectral, stoichiometric ratio, physicochemical, polarity and photostability studies of newly synthesized chalcone dye in organized media

International Nuclear Information System (INIS)

Marwani, Hadi M.; Asiri, Abdullah M.; Khan, Salman A.

2013-01-01

The main focus of this study was to investigate spectroscopic properties, stoichiometric ratios, physicochemical parameters, polarity and photostability behaviors of newly synthesized chalcone dye in organized media. The chalcone dye, 1-(2,5-Dimethyl-thiophen-3-yl)-3-(9-etnyl-9H-carbazol-3-yl)-propenone (DTEP), was prepared by the reaction of carbazole aldehyde with 3-acetyl-2,5-dimethythiophene. Data obtained from FT-IR, 1 H-–NMR, 13 C-NMR and elemental analysis were consistent with chemical structure of newly prepared DTEP. Increases in fluorescence intensities of DTEP with cetyltrimethyl ammonium bromide (CTAB) were observed. In comparison of fluorescence intensities for DTEP with CTAB, reductions in fluorescence intensities for DTEP with sodium dodecyl sulfate (SDS) were noticed under the same experimental and instrumental conditions. Additionally, Benesi–Hildebrand method was applied to determine stoichiometric ratios and association constants of DTEP with CTAB and SDS. Stern–Volmer plot was used in order to further confirm the stoichiometric ratio and association constant of DTEP with SDS. Physicochemical parameters such as singlet absorption, molar absorptivity, oscillator strength, dipole moment and fluorescence quantum yield of DTEP were also determined. Fluorescence polarity study displayed that DTEP was sensitive to the polarity of the microenvironment provided by different solvents. Finally, fluorescence steady-state measurements revealed that DTEP has high photostability against photobleaching. -- Highlights: ► Mechanistic understanding of molecular structure of newly synthesized chalcone dye. ► Exploring spectral behaviors and physicochemical parameters of chalcone dye. ► Determination of stoichiometric ratios and association constants of chalcone dye. ► Determination of fluorescence quantum yield in different solvents. ► High photostability against photobleaching of chalcone dye was observed

Functional polypeptides obtained by living ring opening polymerizations of N-carboxyanhydrides

NARCIS (Netherlands)

Habraken, G.J.M.

2011-01-01

N-Carboxyanhydride ring opening polymerization (NCA ROP) is a method to prepare polypeptides with a high degree of polymerization in large quantities. The living polymerization technique of NCA ROP gave the opportunity to synthesize many polymer architectures with well-defined blocks and copolymers

Biosynthesis of human sialophorins and analysis of the polypeptide core

International Nuclear Information System (INIS)

Remold-O'Donnell, E.; Kenney, D.; Rosen, F.S.

1987-01-01

Biosynthesis was examined of sialophorin (formerly called gpL115) which is altered in the inherited immunodeficiency Wiskott-Aldrich syndrome. Sialophorin is greater than 50% carbohydrate, primarily O-linked units of sialic acid, galactose, and galactosamine. Pulse-labeling with [ 35 S]methionine and chase incubation established that sialophorin is synthesized in CEM lymphoblastoid cells as an Mr 62,000 precursor which is converted within 45 min to mature glycosylated sialophorin, a long-lived molecule. Experiments with tunicamycin and endoglycosidase H demonstrated that sialophorin contains N-linked carbohydrate (approximately two units per molecule) and is therefore an N,O-glycoprotein. Pulse-labeling of tunicamycin-treated CEM cells together with immunoprecipitation provided the means to isolate the [ 35 S]-methionine-labeled polypeptide core of sialophorin and determine its molecular weight (58,000). This datum allowed us to express the previously established composition on a per molecule basis and determine that sialophorin molecules contain approximately 520 amino acid residues and greater than or equal to 100 O-linked carbohydrate units. A recent study showed that various blood cells express sialophorin and that there are two molecular forms: lymphocyte/monocyte sialophorin and platelet/neutrophil sialophorin. Biosynthesis of the two forms was compared by using sialophorin of CEM cells and sialophorin of MOLT-4 cells (another lymphoblastoid line) as models for lymphocyte/monocyte sialophorin and platelet/neutrophil sialophorin, respectively. The time course of biosynthesis and the content of N units were found to be identical for the two sialophorin species. [ 35 S]Methionine-labeled polypeptide cores of CEM sialophorin and MOLT sialophorin were isolated and compared by electrophoresis, isoelectrofocusing, and a newly developed peptide mapping technique

Effect of oxygen on morphogenesis and polypeptide expression by Mucor racemosus

International Nuclear Information System (INIS)

Phillips, G.J.; Borgia, P.T.

1985-01-01

The morphology of Mucor racemosus in cultures continuously sparged with nitrogen gas was investigated. When appropriate precautions were taken to prevent oxygen from entering the cultures, the morphology of the cells was uniformly yeastlike irrespective of the N 2 flow rate. When small amounts of oxygen entered the cultures the resulting microaerobic conditions evoked mycelial development. Polypeptides synthesized by aerobic mycelia, microaerobic mycelia, anaerobic yeasts, and yeasts grown in a CO 2 atmosphere were compared by two-dimensional gel electrophoresis. The results indicated that a large number of differences in polypeptide expression exist when microaerobic mycelia or anaerobic yeasts are compared with aerobic mycelia and that these alterations correlate with a change from an oxidative to a fermentative metabolic mode. The authors hypothesize that oxygen regulates the expression of polypeptides involved in both the metabolic mode and in morphogenesis

Antibacterial activity of three newly-synthesized chalcones & synergism with antibiotics against clinical isolates of methicillin-resistant Staphylococcus aureus

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Dragana D Bozic

2014-01-01

Interpretation & conclusions: o0 ur study demonstrated that three newly-synthesized chalcones exhibited significant anti-MRSA effect and synergism with non-β-lactam antibiotics. The most effective compound was 1,3-Bis-(2-hydroxy-phenyl-propenone. Our results provide useful information for future research of possible application of chalcones in combination with conventional anti-MRSA therapy as promising new antimicrobial agents.

Green methodology for the recovery of Cr (VI from tannery effluent using newly synthesized quaternary ammonium salt

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K.S. Yoganand

2017-02-01

Full Text Available Leather tanning industries release effluents into the river through various canals. These effluents contain chromium (VI contaminating the river and the ground water as well. To fix a solution for this issue a simple and selective solvent extraction method has been applied by using a newly synthesized quaternary ammonium salt viz 2-benzoylethylheptyldimethylammonium bromide. By varying the parameters such as quaternary ammonium salts, sulfuric acid, pH, solvents, equilibration time and aqueous organic ratio the extraction efficiency has been determined.

Side-chain-controlled self-assembly of polystyrene-polypeptide miktoarm star copolymers

KAUST Repository

Junnila, Susanna

2012-03-27

We show how the self-assembly of miktoarm star copolymers can be controlled by modifying the side chains of their polypeptide arms, using A 2B and A 2B 2 type polymer/polypeptide hybrids (macromolecular chimeras). Initially synthesized PS 2PBLL and PS 2PBLL 2 (PS, polystyrene; PBLL, poly(ε-tert-butyloxycarbonyl-l-lysine) ) miktoarms were first deprotected to PS 2PLLHCl and PS 2PLLHCl 2 miktoarms (PLLHCl, poly(l-lysine hydrochloride)) and then complexed ionically with sodium dodecyl sulfonate (DS) to give the supramolecular complexes PS 2PLL(DS) and PS 2(PLL(DS)) 2. The solid-state self-assemblies of these six miktoarm systems were studied by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and small- and wide-angle X-ray scattering (SAXS, WAXS). The side chains of the polypeptide arms were observed to have a large effect on the solubility, polypeptide conformation, and self-assembly of the miktoarms. Three main categories were observed: (i) lamellar self-assemblies at the block copolymer length scale with packed layers of α-helices in PS 2PBLL and PS 2PBLL 2; (ii) charge-clustered polypeptide micelles with less-defined conformations in a nonordered lattice within a PS matrix in PS 2PLLHCl and PS 2PLLHCl 2; (iii) lamellar polypeptide-surfactant self-assemblies with β-sheet conformation in PS 2PLL(DS) and PS 2(PLL(DS)) 2 which dominate over the formation of block copolymer scale structures. Differences between the 3- and 4-arm systems illustrate how packing frustration between the coil-like PS arms and rigid polypeptide conformations can be relieved by the right number of arms, leading to differences in the extent of order. © 2012 American Chemical Society.

Methods for engineering polypeptide variants via somatic hypermutation and polypeptide made thereby

Science.gov (United States)

Tsien, Roger Y; Wang, Lei

2015-01-13

Methods using somatic hypermutation (SHM) for producing polypeptide and nucleic acid variants, and nucleic acids encoding such polypeptide variants are disclosed. Such variants may have desired properties. Also disclosed are novel polypeptides, such as improved fluorescent proteins, produced by the novel methods, and nucleic acids, vectors, and host cells comprising such vectors.

Well-defined (co)polypeptides bearing pendant alkyne groups

KAUST Repository

Zhao, Wei

2016-03-18

A novel metal-free strategy, using hydrogen-bonding catalytic ring opening polymerization of acetylene-functionalized N-carboxy anhydrites of α-amino acids, was developed for the synthesis of well-defined polypeptides bearing pendant alkyne groups. This method provides an efficient way to synthesize novel alkyne-functionalized homopolypeptides (A) and copolypeptides, such as AB diblock (B: non-functionalized), ABA triblock and star-AB diblock, as well as linear and star random copolypeptides, precursors of a plethora complex macromolecular architectures by click chemistry.

Well-defined (co)polypeptides bearing pendant alkyne groups

KAUST Repository

Zhao, Wei; Gnanou, Yves; Hadjichristidis, Nikolaos

2016-01-01

A novel metal-free strategy, using hydrogen-bonding catalytic ring opening polymerization of acetylene-functionalized N-carboxy anhydrites of α-amino acids, was developed for the synthesis of well-defined polypeptides bearing pendant alkyne groups. This method provides an efficient way to synthesize novel alkyne-functionalized homopolypeptides (A) and copolypeptides, such as AB diblock (B: non-functionalized), ABA triblock and star-AB diblock, as well as linear and star random copolypeptides, precursors of a plethora complex macromolecular architectures by click chemistry.

Measurement of T-lymphocyte responses in whole-blood cultures using newly synthesized DNA and ATP.

Science.gov (United States)

Sottong, P R; Rosebrock, J A; Britz, J A; Kramer, T R

2000-03-01

The proliferative response is most frequently determined by estimating the amount of [(3)H]thymidine incorporated into newly synthesized DNA. The [(3)H]thymidine procedure requires the use of radioisotopes as well as lengthy periods of incubation (>72 h). An alternative method of assessing T-lymphocyte activation in whole-blood cultures involves the measurement of the nucleotide ATP instead of [(3)H]thymidine incorporation. In addition, the Luminetics assay of T-cell activation measures specific T-lymphocyte subset responses through the use of paramagnetic particles coated with monoclonal antibodies against CD antigens. This assay permits rapid (24 h) analysis of lymphocyte subset activation responses to mitogens and recall antigens in small amounts of blood.

Role of Side-Chain Molecular Features in Tuning Lower Critical Solution Temperatures (LCSTs) of Oligoethylene Glycol Modified Polypeptides.

Science.gov (United States)

Gharakhanian, Eric G; Deming, Timothy J

2016-07-07

A series of thermoresponsive polypeptides has been synthesized using a methodology that allowed facile adjustment of side-chain functional groups. The lower critical solution temperature (LCST) properties of these polymers in water were then evaluated relative to systematic molecular modifications in their side-chains. It was found that in addition to the number of ethylene glycol repeats in the side-chains, terminal and linker groups also have substantial and predictable effects on cloud point temperatures (Tcp). In particular, we found that the structure of these polypeptides allowed for inclusion of polar hydroxyl groups, which significantly increased their hydrophilicity and decreased the need to use long oligoethylene glycol repeats to obtain LCSTs. The thioether linkages in these polypeptides were found to provide an additional structural feature for reversible switching of both polypeptide conformation and thermoresponsive properties.

Biodistribution of newly synthesized PHEA-based polymer-coated SPION in Sprague Dawley rats as magnetic resonance contrast agent

Directory of Open Access Journals (Sweden)

Park J

2013-10-01

Full Text Available Junsung Park,1,2,* Wonkyung Cho,1,2,* Hee Jun Park,1,2 Kwang-Ho Cha,1,2 Dae-Chul Ha,2,5 Youn-Woong Choi,5 Ha-Young Lee,3 Sun-Hang Cho,5 Sung-Joo Hwang1,4 1Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, Republic of Korea; 2College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea; 3Biomaterials Laboratory, Korea Research Institutes of Chemical Technology, Daejeon, Republic of Korea; 4College of Pharmacy, Yonsei University, Incheon, Republic of Korea; 5Korea United Pharm Inc, Seoul, Republic of Korea *These authors contributed equally to this work Objectives: The purpose of this study was to observe the pharmacokinetic behavior of newly synthesized biocompatible polymers based on polyhydroxyethylaspartamide (PHEA to be used to coat an iron oxide core to make superparamagnetic iron oxide nanoparticles (SPION. Materials and methods: The isotopes [14C] and [59Fe] were used to label the polymer backbone (CLS and iron oxide core (FLS, respectively. In addition, unradiolabeled cold superparamagnetic iron oxide nanoparticles (SPION/ULS were synthesized to characterize particle size by dynamic light scattering, morphology by transmission electron microscopy, and in vivo magnetic resonance imaging (MRI. CLS and FLS were used separately to investigate the behavior of both the synthesized polymer and [Fe] in Sprague Dawley (SD rats, respectively. Because radioactivity of the isotopes was different by β for CLS and γ for FLS, synthesis of the samples had to be separately prepared. Results: The mean particle size of the ULS was 66.1 nm, and the biodistribution of CLS concentrations in various organs, in rank order of magnitude, was liver > kidney > small intestine > other. The biodistribution of FLS concentrations was liver > spleen > lung > other. These rank orders show that synthesized SPION mainly accumulates in the liver. The differences in the distribution were caused by the SPION metabolism. Radiolabeled

Mosaic HIV envelope immunogenic polypeptides

Science.gov (United States)

Korber, Bette T. M.; Gnanakaran, S.; Perkins, Simon; Sodroski, Joseph; Haynes, Barton

2018-01-02

Disclosed herein are mosaic HIV envelope (Env) polypeptides that can elicit an immune response to HIV (such as cytotoxic T cell (CTL), helper T cell, and/or humoral responses). Also disclosed are sets of the disclosed mosaic Env polypeptides, which include two or more (for example, three) of the polypeptides. Also disclosed herein are methods for treating or inhibiting HIV in a subject including administering one or more of the disclosed immunogenic polypeptides or compositions to a subject infected with HIV or at risk of HIV infection. In some embodiments, the methods include inducing an immune response to HIV in a subject comprising administering to the subject at least one (such as two, three, or more) of the immunogenic polypeptides or at least one (such as two, three, or more) nucleic acids encoding at least one of the immunogenic polypeptides disclosed herein.

Stimuli-Triggered Sol-Gel Transitions of Polypeptides Derived from α-Amino Acid N-Carboxyanhydride (NCA) Polymerizations.

Science.gov (United States)

He, Xun; Fan, Jingwei; Wooley, Karen L

2016-02-18

The past decade has witnessed significantly increased interest in the development of smart polypeptide-based organo- and hydrogel systems with stimuli responsiveness, especially those that exhibit sol-gel phase-transition properties, with an anticipation of their utility in the construction of adaptive materials, sensor designs, and controlled release systems, among other applications. Such developments have been facilitated by dramatic progress in controlled polymerizations of α-amino acid N-carboxyanhydrides (NCAs), together with advanced orthogonal functionalization techniques, which have enabled economical and practical syntheses of well-defined polypeptides and peptide hybrid polymeric materials. One-dimensional stacking of polypeptides or peptide aggregations in the forms of certain ordered conformations, such as α helices and β sheets, in combination with further physical or chemical cross-linking, result in the construction of three-dimensional matrices of polypeptide gel systems. The macroscopic sol-gel transitions, resulting from the construction or deconstruction of gel networks and the conformational changes between secondary structures, can be triggered by external stimuli, including environmental factors, electromagnetic fields, and (bio)chemical species. Herein, the most recent advances in polypeptide gel systems are described, covering synthetic strategies, gelation mechanisms, and stimuli-triggered sol-gel transitions, with the aim of demonstrating the relationships between chemical compositions, supramolecular structures, and responsive properties of polypeptide-based organo- and hydrogels. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Homoallylglycine residues are superior precursors to orthogonally modified thioether containing polypeptides.

Science.gov (United States)

Perlin, Pesach; Gharakhanian, Eric G; Deming, Timothy J

2018-06-12

Homoallylglycine N-carboxyanhydride, Hag NCA, monomers were synthesized and used to prepare polypeptides containing Hag segments with controllable lengths of up to 245 repeats. Poly(l-homoallylglycine), GHA, was found to adopt an α-helical conformation, which provided good solubility in organic solvents and allowed high yield functionalization of its alkene side-chains via radical promoted addition of thiols. The conformations of these derivatives were shown to be switchable between α-helical and disordered states in aqueous media using thioether alkylation or oxidation reactions. Incorporation of GHA segments into block copolymers with poly(l-methionine), M, segments provided a means to orthogonally modify thioether side-chains different ways in separate copolypeptide domains. This approach allows preparation of functional polypeptides containing discrete domains of oxidized and alkylated thioether containing residues, where chain conformation and functionality of each domain can be independently modified.

Identification of Newly Synthesized Proteins by Echinococcus granulosus Protoscoleces upon Induction of Strobilation.

Directory of Open Access Journals (Sweden)

João Antonio Debarba

2015-09-01

Full Text Available The proteins responsible for the key molecular events leading to the structural changes between the developmental stages of Echinococcus granulosus remain unknown. In this work, azidohomoalanine (AHA-specific labeling was used to identify proteins expressed by E. granulosus protoscoleces (PSCs upon the induction of strobilar development.The in vitro incorporation of AHA with different tags into newly synthesized proteins (NSPs by PSCs was analyzed using SDS-PAGE and confocal microscopy. The LC-MS/MS analysis of AHA-labeled NSPs by PSCs undergoing strobilation allowed for the identification of 365 proteins, of which 75 were differentially expressed in comparison between the presence or absence of strobilation stimuli and 51 were expressed exclusively in either condition. These proteins were mainly involved in metabolic, regulatory and signaling processes.After the controlled-labeling of proteins during the induction of strobilar development, we identified modifications in protein expression. The changes in the metabolism and the activation of control and signaling pathways may be important for the correct parasite development and be target for further studies.

Complexes cobalt(II, zinc(II and copper(II with some newly synthesized benzimidazole derivatives and their antibacterial activity

Directory of Open Access Journals (Sweden)

S. O. PODUNAVAC-KUZMANOVIC

1999-05-01

Full Text Available The preparation and properties of some complexes of cobalt(II, zinc(II and copper(II with several newly synthesized benzimidazole derivatives (L are reported. The complexes, of the general formula [MCl2L2] (M=Co(II, Zn(II and [CuCl2L(H2O], have a tetrahedral structure. The complexes were characterized by elemental analysis, molar conductivity, magnetic susceptibility measurements, IR and absorption electronic spectra. The antibacterial activitiy of the benzimidazoles and their complexes was evaluated against Erwinia carotovora subsp. carotovora and Erwinia amylovora. The complexes were found to be more toxic than the ligands.

Electrochemical Study on Newly Synthesized Chlorocurcumin as an Inhibitor for Mild Steel Corrosion in Hydrochloric Acid

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Ahmed A. Al-Amiery

2013-11-01

Full Text Available A new curcumin derivative, i.e., (1E,4Z,6E-5-chloro-1,7-bis(4-hydroxy-3-methoxyphenylhepta-1,4,6-trien-3-one (chlorocurcumin, was prepared starting with the natural compound curcumin. The newly synthesized compound was characterized by elemental analysis and spectral studies (IR, 1H-NMR and 13C-NMR. The corrosion inhibition of mild steel in 1 M HCl by chlorocurcumin has been studied using potentiodynamic polarization (PDP measurements and electrochemical impedance spectroscopy (EIS. The inhibition efficiency increases with the concentration of the inhibitor but decreases with increases in temperature. The potentiodynamic polarization reveals that chlorocurcumin is a mixed-type inhibitor. The kinetic parameters for mild steel corrosion were determined and discussed.

Electrochemical Study on Newly Synthesized Chlorocurcumin as an Inhibitor for Mild Steel Corrosion in Hydrochloric Acid

Science.gov (United States)

Al-Amiery, Ahmed A.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar; Musa, Ahmed Y.; Li, Cheong Jiun

2013-01-01

A new curcumin derivative, i.e., (1E,4Z,6E)-5-chloro-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,4,6-trien-3-one (chlorocurcumin), was prepared starting with the natural compound curcumin. The newly synthesized compound was characterized by elemental analysis and spectral studies (IR, 1H-NMR and 13C-NMR). The corrosion inhibition of mild steel in 1 M HCl by chlorocurcumin has been studied using potentiodynamic polarization (PDP) measurements and electrochemical impedance spectroscopy (EIS). The inhibition efficiency increases with the concentration of the inhibitor but decreases with increases in temperature. The potentiodynamic polarization reveals that chlorocurcumin is a mixed-type inhibitor. The kinetic parameters for mild steel corrosion were determined and discussed. PMID:28788402

Aqueous cholesteric liquid crystals using uncharged rodlike polypeptides. Polypeptide vesicles by conformation-specific assembly. Ordered chiral macroporous hybrid silica-polypeptide composites

Science.gov (United States)

Bellomo, Enrico Giuseppe

2005-07-01

Aqueous cholesteric liquid crystals using uncharged rodlike polypeptides . The aqueous, lyotropic liquid-crystalline phase behavior of an alpha helical polypeptide, has been studied using optical microscopy and X-ray scattering. Solutions of optically pure polypeptide were found to form cholesteric liquid crystals at volume fractions that decreased with increasing average chain length. At very high volume fractions, the formation of a hexagonal mesophase was observed. The pitch of the cholesteric phase could be varied by a mixture of enantiomeric samples, where the pitch increased as the mixture approached equimolar. The cholesteric phases could be untwisted, using either magnetic field or shear flow, into nematic phases, which relaxed into cholesterics upon removal of field or shear. We have found that the phase diagram of this polypeptide in aqueous solution parallels that of poly(gamma-benzyl glutamate) in organic solvents, thus providing a useful system for liquid-crystal applications requiring water as solvent. Polypeptide vesicles by conformation-specific assembly. We have found that block copolymers composed of polypeptide segments provide significant advantages in controlling both the function and supramolecular structure of bioinspired self-assemblies. Incorporation of the stable chain conformations found in proteins into block copolymers was found to provide an additional element of control, beyond amphiphilicity and composition that defines self-assembled architecture. The abundance of functionality present in amino acids, and the ease by which they can be incorporated into these materials, also provides a powerful mechanism to impart block copolypeptides with function. This combination of structure and function work synergistically to enable significant advantages in the preparation of therapeutic agents as well as provide insight into design of self-assemblies beginning to approach the complexity of natural structures such as virus capsids. Ordered

A newly synthesized macakurzin C-derivative attenuates acute and chronic skin inflammation: The Nrf2/heme oxygenase signaling as a potential target

Energy Technology Data Exchange (ETDEWEB)

Akram, Muhammad [College of Pharmacy Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan (Korea, Republic of); Shin, Iljin [College of Pharmacy and Research Institute of Pharmaceutical Science and Technology (RIPST), Ajou University, Suwon (Korea, Republic of); Kim, Kyeong-A; Noh, Dabi [College of Pharmacy Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan (Korea, Republic of); Baek, Seung-Hoon; Chang, Sun-Young [College of Pharmacy and Research Institute of Pharmaceutical Science and Technology (RIPST), Ajou University, Suwon (Korea, Republic of); Kim, Hyoungsu, E-mail: hkimajou@ajou.ac.kr [College of Pharmacy and Research Institute of Pharmaceutical Science and Technology (RIPST), Ajou University, Suwon (Korea, Republic of); Bae, Ok-Nam, E-mail: onbae@hanyang.ac.kr [College of Pharmacy Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan (Korea, Republic of)

2016-09-15

Impaired immune responses in skin play a pivotal role in the development and progression of chemical-associated inflammatory skin disorders. In this study, we synthesized new flavonoid derivatives from macakurzin C, and identified in vitro and in vivo efficacy of a potent anti-inflammatory flavonoid, Compound 14 (CPD 14), with its underlying mechanisms. In lipopolysaccharide (LPS)-stimulated murine macrophages and IFN-γ/TNF-α-stimulated human keratinocytes, CPD 14 significantly inhibited the release of inflammatory mediators including nitric oxide (NO), prostaglandins, and cytokines (IC{sub 50} for NO inhibition in macrophages: 4.61 μM). Attenuated NF-κB signaling and activated Nrf2/HO-1 pathway were responsible for the anti-inflammatory effects of CPD 14. The in vivo relevance was examined in phorbol 12-myristate 13-acetate (TPA)-induced acute skin inflammation and oxazolone-induced atopic dermatitis models. Topically applied CPD 14 significantly protected both irritation- and sensitization-associated skin inflammation by suppressing the expression of inflammatory mediators. In summary, we demonstrated that a newly synthesized flavonoid, CPD 14, has potent inhibitory effects on skin inflammation, suggesting it is a potential therapeutic candidate to treat skin disorders associated with excessive inflammation. - Highlights: • An anti-inflammatory flavonoid CPD 14 was newly synthesized from macakurzin C. • CPD 14 potently inhibited inflammatory reaction in keratinocytes and macrophages. • Dermal toxicity by irritation or sensitization in rats was protected by CPD 14. • Attenuated NF-κB and activated Nrf2/HO-1 were main mechanisms of CPD 14 action.

Architecture effects on multivalent interactions by polypeptide-based multivalent ligands

Science.gov (United States)

Liu, Shuang

protein materials, including structural as well as functional proteins. Therefore, polypeptide-based multivalent scaffolds are used to display ligands to assess the contribution of different architectural parameters to the multivalent binding events. In this work, a family of alanine-rich alpha-helical glycopolypeptides was designed and synthesized by a combination of protein engineering and chemical coupling, to display two types of saccharide ligands for two different multivalent binding systems. The valencies, chain length and spacing between adjacent ligands of these multivalent ligands were designed in order to study architecture effects on multivalent interactions. The polypeptides and their glycoconjugates were characterized via various methods, including SDS-PAGE, NMR, HPLC, amino acid analysis (AAA), MALDI, circular dichroism (CD) and GPC. In the first multivalent binding system, cholera toxin B pentamer (CT B5) was chosen to be the protein receptor due to its well-characterized structure, lack of significant steric interference of binding to multiple binding sites, and requirement of only simple monosaccharide as ligands. Galactopyranoside was incorporated into polypeptide scaffolds through amine-carboxylic acid coupling to the side chains of glutamic acid residues. The inhibition and binding to CT B5 of these glycopolypeptide ligands were evaluated by direct enzyme-linked assay (DELA). As a complement method, weak affinity chromatography (WAC) was also used to evaluate glycopolypeptides binding to a CT B5 immobilized column. The architecture effects on CT B 5 inhibition are discussed. In the second system, cell surface receptor L-selectin was targeted by polypeptide-based multivalent ligands containing disulfated galactopyranoside ligands, due to its important roles in various immunological activities. The effects of glycopolypeptide architectural variables L-selectin shedding were evaluated via ELISA-based assays. These polypeptide-based multivalent ligands

An anti-cancer WxxxE-containing azurin polypeptide inhibits Rac1-dependent STAT3 and ERK/GSK-3β signaling in breast cancer cells.

Science.gov (United States)

Zhang, Zhe; Luo, Zhiyong; Min, Wenpu; Zhang, Lin; Wu, Yaqun; Hu, Xiaopeng

2017-06-27

In our previous study, we characterized a mycoplasmal small GTPase-like polypeptide of 240 amino acids that possesses an N-terminal WVLGE sequence. The N-terminal WVLGE sequence promotes activation of Rac1 and subsequent host cancer cell proliferation. To investigate the function of the WxxxE motif in the interaction with Rac1 and host tumor progression, we synthesized a 35-amino acid WVLGE-containing polypeptide derived from a cell-penetrating peptide derived from the azurin protein. We verified that the WVLGE-containing polypeptide targeted MCF-7 cells rather than MCF-10A cells. However, the WVLGE-containing polypeptide inhibited activation of Rac1 and induced cellular phenotypes that resulted from inhibition of Rac1. In addition, the WVLGE-containing polypeptide down-regulated phosphorylation of the STAT3 and ERK/GSK-3β signaling pathways, and this effect was abolished by either stimulation or inhibition of Rac1 activity. We also found that the WVLGE-containing polypeptide has a Rac1-dependent potential to suppress breast cancer growth in vitro and in vivo. We suggest that by acting as a Rac1 inhibitor, this novel polypeptide may be useful for the treatment of breast cancer.

Methods for using polypeptides having cellobiohydrolase activity

Science.gov (United States)

Morant, Marc D; Harris, Paul

2016-08-23

The present invention relates to isolated polypeptides having cellobiohydrolase activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

Polynucleotides encoding polypeptides having beta-glucosidase activity

Science.gov (United States)

Harris, Paul; Golightly, Elizabeth

2010-03-02

The present invention relates to isolated polypeptides having beta-glucosidase activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods for producing and using the polypeptides.

Induction of salivary polypeptides associated with parotid hypertrophy by gallotannins administered topically into the mouse mouth.

Science.gov (United States)

Gho, Francesca; Peña-Neira, Alvaro; López-Solís, Remigio O

2007-02-01

Isoproterenol-induced salivary polypeptides (IISP), a group of proline-rich proteins synthesized by mouse parotids, have been considered as markers for isoproterenol-induced parotid hypertrophy. Rodents fed diets containing high-tannin cereals (sorghum), also develop parotid hypertrophy. To test whether tannins are directly involved in provoking sialotrophic growth, we studied the effect of intraperitoneal and topical oral administrations of tannic acid (TA) on the induction of IISP polypeptides in endogamic mice (A/Snell). TA was characterized by HPLC chromatography and spectral analysis and shown to be composed solely of gallotannins, a complex family of glucose and gallic acid esters. IISP polypeptides were monitored in saliva by SDS-polyacrylamide gel electrophoresis during 36 h after ending TA stimulation. Single daily intraperitoneal administrations of TA for 3 consecutive days (0.033 mg/g bw/day), at variance of parallel administrations of isoproterenol (0.042 mg/g bw/day) failed to induce IISP polypeptides. However, repeated topical applications of TA into the mouse mouths (1.21 mg/g bw divided into three equal doses given at 4-h intervals within a single day) resulted in unequivocal induction of IISP polypeptides. That response was clearly intensified by increasing the stimulation frequency to eight equivalent doses given at 1.5-h intervals within a single day (corresponding to 3.23 mg/g bw) and even further by repeating this protocol for 3 days. Under these productive schemes of stimulations by TA, electrophoretic fractionation of parotid homogenates showed new polypeptide bands migrating in parallel to salivary IISP. These results suggest that topically administered gallotannins are effective inducers of trophic growth in mouse parotids.

Micelles Formed by Polypeptide Containing Polymers Synthesized Via N-Carboxy Anhydrides and Their Application for Cancer Treatment

Directory of Open Access Journals (Sweden)

Dimitrios Skoulas

2017-06-01

Full Text Available The development of multifunctional polymeric materials for biological applications is mainly guided by the goal of achieving the encapsulation of pharmaceutical compounds through a self-assembly process to form nanoconstructs that control the biodistribution of the active compounds, and therefore minimize systemic side effects. Micelles are formed from amphiphilic polymers in a selective solvent. In biological applications, micelles are formed in water, and their cores are loaded with hydrophobic pharmaceutics, where they are solubilized and are usually delivered through the blood compartment. Even though a large number of polymeric materials that form nanocarrier delivery systems has been investigated, a surprisingly small subset of these technologies has demonstrated potentially curative preclinical results, and fewer have progressed towards commercialization. One of the most promising classes of polymeric materials for drug delivery applications is polypeptides, which combine the properties of the conventional polymers with the 3D structure of natural proteins, i.e., α-helices and β-sheets. In this article, the synthetic pathways followed to develop well-defined polymeric micelles based on polypeptides prepared through ring-opening polymerization (ROP of N-carboxy anhydrides are reviewed. Among these works, we focus on studies performed on micellar delivery systems to treat cancer. The review is limited to systems presented from 2000–2017.

Polypeptides having catalase activity and polynucleotides encoding same

Energy Technology Data Exchange (ETDEWEB)

Liu, Ye; Duan, Junxin; Zhang, Yu; Tang, Lan

2017-05-02

Provided are isolated polypeptides having catalase activity and polynucleotides encoding the polypeptides. Also provided are nucleic acid constructs, vectors and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

Biomimetic Synthesis of Gelatin Polypeptide-Assisted Noble-Metal Nanoparticles and Their Interaction Study

Science.gov (United States)

Liu, Ying; Liu, Xiaoheng; Wang, Xin

2011-12-01

Herein, the generation of gold, silver, and silver-gold (Ag-Au) bimetallic nanoparticles was carried out in collagen (gelatin) solution. It first showed that the major ingredient in gelatin polypeptide, glutamic acid, acted as reducing agent to biomimetically synthesize noble metal nanoparticles at 80°C. The size of nanoparticles can be controlled not only by the mass ratio of gelatin to gold ion but also by pH of gelatin solution. Interaction between noble-metal nanoparticles and polypeptide has been investigated by TEM, UV-visible, fluorescence spectroscopy, and HNMR. This study testified that the degradation of gelatin protein could not alter the morphology of nanoparticles, but it made nanoparticles aggregated clusters array (opposing three-dimensional α-helix folding structure) into isolated nanoparticles stabilized by gelatin residues. This is a promising merit of gelatin to apply in the synthesis of nanoparticles. Therefore, gelatin protein is an excellent template for biomimetic synthesis of noble metal/bimetallic nanoparticle growth to form nanometer-sized device.

Polypeptides having cellobiohydrolase activity and polynucleotides encoding same

Science.gov (United States)

Morant, Marc D.; Harris, Paul

2015-10-13

The present invention relates to isolated polypeptides having cellobiohydrolase activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

Polypeptides having xylanase activity and polynucleotides encoding same

Energy Technology Data Exchange (ETDEWEB)

Spodsberg, Nikolaj

2018-02-06

The present invention relates to isolated polypeptides having xylanase activity and polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

Measles virus polypeptides in purified virions and in infected cells

International Nuclear Information System (INIS)

Vainionpaeae, R.; Ziola, B.; Salmi, A.

1978-01-01

A wild-type measles virus was radiolabeled during growth in VERO cells and purified by two successive potassium tartrate gradient centrifugations. The virion polypeptide composition was determined by SDS-polyacrylamide gel electrophoresis employing two different buffer systems. Six virus-specific polypeptides were consistently detected. The largest (L) had a molecular weight (MW) of greater than 150,000. The second largest polypeptide, G (MW 79,000), was the only glycoprotein found. The proteins designated polypeptide 2 (MW 66 to 70,000) and nucleocapsid protein or NP (MW 61,000) were phosphorylated. The remaining virus-coded proteins were polypeptide 5 (MW 40,000) and the matrix or M protein (MW 37,000). Measles virions also contained a polypeptide (MW 42,000) thought to be actin due to co-migration with this component of uninfected cells. Analysis of in vitro 3 H-acetic anhydride radiolabeled virions confirmed the presence of these seven polypeptides. Acetic anhydride also labeled a protein designated polypeptide 4 (MW 53,000) which was not consistently radiolabeled in vivo, as well as several other minor proteins believed to be cellular in origin. Synthesis of the six virus-specific structural polypeptides was detected in lysates of infected cells by SDS-polyacrylamide slab gel electrophoresis. Virus specificity of polypeptide 4 could not be confirmed due to the similar MW of several cellular polypeptides. Two non-virion, but virus-specified polypeptides, of MW 38,000 and 18,000 were also detected. Synthesis of the virus structural proteins was in the same proportions as the polypeptides found in virions except for under production of polypeptide G and over production of polypeptide 2. (author)

Size and frequency of gaps in newly synthesized DNA of xeroderma pigmentosum human cells irradiated with ultraviolet light

International Nuclear Information System (INIS)

Meneghini, R.; Cordeiro-Stone, M.; Schumacher, R.I.

1981-01-01

Native newly synthesized DNA from human cells (xeroderma pigmentosum type) irradiated with ultraviolet light releases short pieces of DNA (L-DNA) when incubated with the single-strand specific S 1 nuclease. This is not observed in the case of unirradiated cells. Previous experiments had shown that the L-DNA resulted from the action of S 1 nuclease upon gaps, i.e., single-stranded DNA discontinuities in larger pieces of double-stranded DNA. We verified that the duplex L-DNA, that arises from the inter-gap regions upon S 1 nuclease treatment, has a size which approximates the distance between two pyrimidine dimers on the same strand. A method was devised to measure the size of the gaps. These parameters have been considered in the proposition of a model for DNA synthesis on a template containing pyrimidine dimers

Spectroscopic and structural study of the newly synthesized heteroligand complex of copper with creatinine and urea.

Science.gov (United States)

Gangopadhyay, Debraj; Singh, Sachin Kumar; Sharma, Poornima; Mishra, Hirdyesh; Unnikrishnan, V K; Singh, Bachcha; Singh, Ranjan K

2016-02-05

Study of copper complex of creatinine and urea is very important in life science and medicine. In this paper, spectroscopic and structural study of a newly synthesized heteroligand complex of copper with creatinine and urea has been discussed. Structural studies have been carried out using DFT calculations and spectroscopic analyses were carried out by FT-IR, Raman, UV-vis absorption and fluorescence techniques. The copper complex of creatinine and the heteroligand complex were found to have much increased water solubility as compared to pure creatinine. The analysis of FT-IR and Raman spectra helps to understand the coordination properties of the two ligands and to determine the probable structure of the heteroligand complex. The LIBS spectra of the heteroligand complex reveal that the complex is free from other metal impurities. UV-visible absorption spectra and the fluorescence emission spectra of the aqueous solution of Cu-Crn-urea heteroligand complex at different solute concentrations have been analyzed and the complex is found to be rigid and stable in its monomeric form at very low concentrations. Copyright © 2015 Elsevier B.V. All rights reserved.

The Human Nuclear Exosome Targeting Complex Is Loaded onto Newly Synthesized RNA to Direct Early Ribonucleolysis

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Michal Lubas

2015-01-01

Full Text Available The RNA exosome complex constitutes the major nuclear eukaryotic 3′-5′ exonuclease. Outside of nucleoli, the human nucleoplasmic exosome is directed to some of its substrates by the nuclear exosome targeting (NEXT complex. How NEXT targets RNA has remained elusive. Using an in vivo crosslinking approach, we report global RNA binding sites of RBM7, a key component of NEXT. RBM7 associates broadly with RNA polymerase II-derived RNA, including pre-mRNA and short-lived exosome substrates such as promoter upstream transcripts (PROMPTs, enhancer RNAs (eRNAs, and 3′-extended products from snRNA and replication-dependent histone genes. Within pre-mRNA, RBM7 accumulates at the 3′ ends of introns, and pulse-labeling experiments demonstrate that RBM7/NEXT defines an early exosome-targeting pathway for 3′-extended snoRNAs derived from such introns. We propose that RBM7 is generally loaded onto newly synthesized RNA to accommodate exosome action in case of available unprotected RNA 3′ ends.

Newly synthesized proteins in seminiferous intertubular and intratubular compartments of the rat testis

International Nuclear Information System (INIS)

Shabanowitz, R.B.; Kierszenbaum, A.L.

1986-01-01

Two-dimensional gel electrophoresis combined with autoradiography and Western blot procedures have been used to characterize newly synthesized proteins in testicular intertubular fluid (TIF) and seminiferous tubular fluid (SNF). Fluids were collected following in vivo and in vitro intratesticular injection of [ 35 S]methionine into control and hypophysectomized adult rats. A discrete number of [ 35 S]methionine-labeled proteins were detected within TIF and SNF. Their presence and relative abundance varied according to in vivo and in vitro labeling conditions. While two major blood plasma proteins, albumin and transferrin, were radioactively labeled after in vivo labeling, these two proteins were insignificantly labeled in samples collected after in vitro labeling. Three acidic proteins, possibly secreted by Sertoli cells (Mr = 72,000, 45,000 and 35,000), were more abundant in TIF samples collected after in vitro [ 35 S]methionine labeling than after in vivo labeling. Incubated seminiferous tubules and TIF of hypophysectomized rats showed a decrease in [35S]methionine-labeling intensity of the Mr = 72,000 acidic protein, possibly reflecting changes in the seminiferous epithelium caused by pituitary hormonal deprivation. Autoradiographs of TIF and most remarkably, of SNF, showed many protein spots that suggested cell breakage and leakage during sample collection. Results of this study suggest that most albumin and transferrin found in TIF and SNF have an extratesticular origin and that proteins secreted by the Sertoli cell can gain access to both TIF and SNF

Ring-Opening Polymerization of N-Carboxyanhydrides for Preparation of Polypeptides and Polypeptide-Based Hybrid Materials with Various Molecular Architectures

KAUST Repository

Pahovnik, David; Hadjichristidis, Nikolaos

2015-01-01

Different synthetic approaches utilizing ring-opening polymerization of N-carboxyanhydrides for preparation of polypeptide and polypeptide-based hybrid materials with various molecular architectures are described. An overview of polymerization

Polypeptides having xylanase activity and polynucleotides encoding same

Energy Technology Data Exchange (ETDEWEB)

Spodsberg, Nikolaj; Shaghasi, Tarana

2017-06-20

The present invention relates to polypeptides having xylanase activity, catalytic domains, and carbohydrate binding domains, and polynucleotides encoding the polypeptides, catalytic domains, and carbohydrate binding domains. The present invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides, catalytic domains, and carbohydrate binding domains.

Phase transitions in polypeptides: analysis of energy fluctuations

DEFF Research Database (Denmark)

Yakubovich, Alexander V.; Solov'yov, Ilia; Solov'yov, Andrey V.

2009-01-01

The helix random coil transition in alanine, valine, and leucine polypeptides consisting of 30 amino acids is studied in vacuo using the Langevin molecular dynamics approach. The influence of side chain radicals on internal energy and heat capacity of the polypeptides is discussed. The heat...... of simulation time. This study provides a comparison of methods for the description of structural transitions in polypeptides....

Newly Synthesized Doxorubicin Complexes with Selected Metals—Synthesis, Structure and Anti-Breast Cancer Activity

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Agata Jabłońska-Trypuć

2017-07-01

Full Text Available Doxorubicin (DOX is very effective chemotherapeutic agent, however it has several major drawbacks. Therefore the motivation for developing novel drug complexes as anticancer agents with different mechanism of action has arisen. The aim of the present study was to evaluate the influence of newly synthesized DOX complexes with selected metals (Mg, Mn, Co, Ni, Fe, Cu, Zn on apoptosis, cell cycle, viability, proliferation and cytotoxicity in the breast cancer cell line MCF-7. Complexation of DOX with metals has likewise been the subject of our research. The current work showed that the tested bivalent metals at a given pH condition formed metal:DOX complexes in a ratio of 2:1, while iron complexes with DOX in a ratio of 3:1. The studies also showed that selected metal-DOX complexes (Mg-DOX, Mn-DOX, Ni-DOX at 0.5 µM concentration significantly decreased cell viability and proliferation, however they increased caspase 7 activity. Results also indicated that studied metal-DOX complexes showed high cytotoxicity in MCF-7 cells. Therefore they were chosen for cell cycle check-points and apoptosis/necrosis analysis studied by flow cytometry. Obtained results suggest that doxorubicin complexed by specified metals can be considered as a potential anti-breast cancer agent, which is characterized by a higher efficacy than a parent drug.

Near infrared imaging-guided photodynamic therapy under an extremely low energy of light by galactose targeted amphiphilic polypeptide micelle encapsulating BODIPY-Br2.

Science.gov (United States)

Liu, Le; Ruan, Zheng; Li, Tuanwei; Yuan, Pan; Yan, Lifeng

2016-10-18

Near infrared (NIR) imaging-guided photodynamic therapy (PDT) is attractive, especially the utilization of one dye as both a photosensitizer and fluorescent probe, and the as-synthesized BODIPY-Br 2 molecule is a candidate. Here, a galactose targeted amphiphilic copolymer of a polypeptide was synthesized and its micelles work as nanocarriers for BODIPY for targeting the NIR imaging-guided PDT of hepatoma cancer cells. At the same time, BODIPY could light up the cytoplasm for real-time imaging and kill cancer cells when the light was switched on. In vitro tests performed on both HepG2 and HeLa cells confirmed that the as-prepared PMAGP-POEGMA-PLys-B micelles showed efficient cell suppression of the cells with galactose receptors in the presence of light under an extremely low energy density (6.5 J cm -2 ). This protocol highlights the potential of polypeptides as biodegradable carriers for NIR image-guided and confined targeting photodynamic therapy.

Polypeptides having beta-glucosidase activity and polynucleotides encoding same

Science.gov (United States)

Harris, Paul; Golightly, Elizabeth

2012-11-27

The present invention relates to isolated polypeptides having beta-glucosidase activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods for producing and using the polypeptides.

Polypeptides having cellulolytic enhancing activity and polynucleotides encoding same

Science.gov (United States)

Maiyuran, Suchindra; Kramer, Randall; Harris, Paul

2013-10-29

The present invention relates to isolated polypeptides having cellulolytic enhancing activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

Chirality-selected phase behaviour in ionic polypeptide complexes

Science.gov (United States)

Perry, Sarah L.; Leon, Lorraine; Hoffmann, Kyle Q.; Kade, Matthew J.; Priftis, Dimitrios; Black, Katie A.; Wong, Derek; Klein, Ryan A.; Pierce, Charles F.; Margossian, Khatcher O.; Whitmer, Jonathan K.; Qin, Jian; de Pablo, Juan J.; Tirrell, Matthew

2015-01-01

Polyelectrolyte complexes present new opportunities for self-assembled soft matter. Factors determining whether the phase of the complex is solid or liquid remain unclear. Ionic polypeptides enable examination of the effects of stereochemistry on complex formation. Here we demonstrate that chirality determines the state of polyelectrolyte complexes, formed from mixing dilute solutions of oppositely charged polypeptides, via a combination of electrostatic and hydrogen-bonding interactions. Fluid complexes occur when at least one of the polypeptides in the mixture is racemic, which disrupts backbone hydrogen-bonding networks. Pairs of purely chiral polypeptides, of any sense, form compact, fibrillar solids with a β-sheet structure. Analogous behaviour occurs in micelles formed from polypeptide block copolymers with polyethylene oxide, where assembly into aggregates with either solid or fluid cores, and eventually into ordered phases at high concentrations, is possible. Chirality is an exploitable tool for manipulating material properties in polyelectrolyte complexation. PMID:25586861

Vasoactive intestinal polypeptide and other preprovasoactive intestinal polypeptide-derived peptides in the female and male genital tract: localization, biosynthesis, and functional and clinical significance

DEFF Research Database (Denmark)

Ottesen, B; Fahrenkrug, J

1995-01-01

Vasoactive intestinal polypeptide, a neuropeptide with wide distribution in the central and peripheral nervous system, has a broad spectrum of biologic actions. The demonstration of vasoactive intestinal polypeptide containing nerve fibers within the female and male genital tract 17 years ago...... indicated a putative role for this peptide in the local nervous control of reproductive functions. The genes encoding the preprovasoactive intestinal polypeptide precursor molecule and the vasoactive intestinal polypeptide receptor have been identified. The gene expression has been studied by the use...... in the genital tracts (i.e., blood flow and nonvascular smooth muscle relaxation). In the ovary vasoactive intestinal polypeptide seems to play an important role as regulator and/or modulator of folliculogenesis and steroidogenesis. In the male genital tract vasoactive intestinal polypeptide seems to participate...

Fluorescence quenching of newly synthesized biologically active coumarin derivative by aniline in binary solvent mixtures

International Nuclear Information System (INIS)

Evale, Basavaraj G.; Hanagodimath, S.M.

2009-01-01

The fluorescence quenching of newly synthesized coumarin (chromen-2-one) derivative, 4-(5-methyl-3-furan-2-yl-benzofuran-2-yl)-7-methyl-chromen-2-one (MFBMC) by aniline in different solvent mixtures of benzene and acetonitrile was determined at room temperature (296 K) by steady-state fluorescence measurements. The quenching is found to be appreciable and positive deviation from linearity was observed in the Stern-Volmer (S-V) plots in all the solvent mixtures. This could be explained by static and dynamic quenching models. The positive deviation in the S-V plot is interpreted in terms of ground-state complex formation model and sphere of action static quenching model. Various rate parameters for the fluorescence quenching process have been determined by using the modified Stern-Volmer equation. The sphere of action static quenching model agrees very well with experimental results. The dependence of Stern-Volmer constant K SV , on dielectric constant ε of the solvent mixture suggests that the fluorescence quenching is diffusion-limited. Further with the use of finite sink approximation model, it is concluded that these bimolecular quenching reactions are diffusion-limited. Using lifetime (τ o ) data, the distance parameter R' and mutual diffusion coefficient D are estimated independently.

Vasorelaxant Effect of a Newly Synthesized Dihydropyridine Ethyl Ester (DHPEE on Rat Thoracic Aorta: Dual Mechanism of Action

Directory of Open Access Journals (Sweden)

Hossein Babaei

2011-06-01

Full Text Available Introduction: DHPEE is a newly synthesized compound by merging the key structural elements in an angiotensin receptor blocker (Telmisartan with key structural elements in 1,4- dihydropyridine calcium channel blocker (Nifedipine. In this study, we examined dual calcium channel blocking and AT1 antagonist activity for DHPEE. Methods: The functional inhibitory characteristics of DHPEE were studied in vitro in rat thoracic aorta preparations precontracted by phenylephrine (1µM or KCl (80µM or Ang II in normal or calcium-free solutions. Results: Concentration–dependent significant relaxation was observed in aortic rings precontracted with phenylephrine, KCl or Ang II. The tension increment produced by increasing external calcium was also reduced by DHPEE. DHPEE caused a marked decrease in the maximal contractile response of the vasoactive agents and shifted their concentration-response curves to the right. Conclusion: DHPEE possesses dual characteristics and cause vasorelaxation by blocking the L-type calcium channels and blocking Ang II receptors (AT1 in rat aortic smooth muscle.

[New drug developments of snake venom polypeptides and progress].

Science.gov (United States)

Fu, Sihai; Feng, Mei; Xiong, Yan

2017-11-28

The value of snake venom polypeptides in clinical application has drawn extensive attention, and the development of snake polypeptides into new drugs with anti-tumor, anti-inflammatory, antithrombotic, analgesic or antihypertensive properties has become the recent research hotspot. With the rapid development of molecular biology and biotechnology, the mechanisms of snake venom polypeptides are also gradually clarified. Numerous studies have demonstrated that snake venom polypeptides exert their pharmacological effects by regulating ion channels, cell proliferation, apoptosis, intracellular signaling pathway, and expression of cytokine as well as binding to relevant active sites or receptors.

Caffeine-water-polypeptide interaction in aqueous solution

Science.gov (United States)

Ghabi, Habib; Dhahbi, Mahmoud

1999-04-01

The interaction of caffeine monomer with the synthetic polypeptides polyasparagine (pAg) and polyaspartic acid (pAsp) was studied by UV spectrophotometry. The results show that different types of interactions are possible depending on the nature of polypeptide. The form of the complex was discussed.

Association with β-COP Regulates the Trafficking of the Newly Synthesized Na,K-ATPase*

Science.gov (United States)

Morton, Michael J.; Farr, Glen A.; Hull, Michael; Capendeguy, Oihana; Horisberger, Jean-Daniel; Caplan, Michael J.

2010-01-01

Plasma membrane expression of the Na,K-ATPase requires assembly of its α- and β-subunits. Using a novel labeling technique to identify Na,K-ATPase partner proteins, we detected an interaction between the Na,K-ATPase α-subunit and the coat protein, β-COP, a component of the COP-I complex. When expressed in the absence of the Na,K-ATPase β-subunit, the Na,K-ATPase α-subunit interacts with β-COP, is retained in the endoplasmic reticulum, and is targeted for degradation. In the presence of the Na,K-ATPase β-subunit, the α-subunit does not interact with β-COP and traffics to the plasma membrane. Pulse-chase experiments demonstrate that in cells expressing both the Na,K-ATPase α- and β-subunits, newly synthesized α-subunit associates with β-COP immediately after its synthesis but that this interaction does not constitute an obligate intermediate in the assembly of the α- and β-subunits to form the pump holoenzyme. The interaction with β-COP was reduced by mutating a dibasic motif at Lys54 in the Na,K-ATPase α-subunit. This mutant α-subunit is not retained in the endoplasmic reticulum and reaches the plasma membrane, even in the absence of Na,K-ATPase β-subunit expression. Although the Lys54 α-subunit reaches the cell surface without need for β-subunit assembly, it is only functional as an ion-transporting ATPase in the presence of the β-subunit. PMID:20801885

A pH- and temperature-responsive bioresorbable injectable hydrogel based on polypeptide block copolymers for the sustained delivery of proteins in vivo.

Science.gov (United States)

Turabee, Md Hasan; Thambi, Thavasyappan; Duong, Huu Thuy Trang; Jeong, Ji Hoon; Lee, Doo Sung

2018-02-27

Sustained delivery of protein therapeutics is limited owing to the fragile nature of proteins. Despite its great potential, delivery of proteins without any loss of bioactivity remains a challenge in the use of protein therapeutics in the clinic. To surmount this shortcoming, we report a pH- and temperature-responsive in situ-forming injectable hydrogel based on comb-type polypeptide block copolymers for the controlled delivery of proteins. Polypeptide block copolymers, composed of hydrophilic polyethylene glycol (PEG), temperature-responsive poly(γ-benzyl-l-glutamate) (PBLG), and pH-responsive oligo(sulfamethazine) (OSM), exhibit pH- and temperature-induced sol-to-gel transition behavior in aqueous solutions. Polypeptide block copolymers were synthesized by combining N-carboxyanhydride-based ring-opening polymerization and post-functionalization of the chain-end using N-hydroxy succinimide ester activated OSM. The physical properties of polypeptide-based hydrogels were tuned by varying the composition of temperature- and pH-responsive PBLG and OSM in block copolymers. Polypeptide block copolymers were non-toxic to human embryonic kidney cells at high concentrations (2000 μg mL -1 ). Subcutaneous administration of polypeptide block copolymer sols formed viscoelastic gel instantly at the back of Sprague-Dawley (SD) rats. The in vivo gels exhibited sustained degradation and were found to be bioresorbable in 6 weeks without any noticeable inflammation at the injection site. Anionic characteristics of hydrogels allow efficient loading of a cationic model protein, lysozyme, through electrostatic interaction. Lysozyme-loaded polypeptide block copolymer sols readily formed a viscoelastic gel in vivo and sustained lysozyme release for at least a week. Overall, the results demonstrate an elegant approach to control the release of certain charged proteins and open a myriad of therapeutic possibilities in protein therapeutics.

Deposition of newly synthesized histones: new histones H2A and H2B do not deposit in the same nucleosome with new Histones H3 and H4

International Nuclear Information System (INIS)

Jackson, V.

1987-01-01

The authors have developed procedures to study histone-histone interactions during the deposition of histones in replicating cells. Cells are labeled for 60 min with dense amino acids, and subsequently, the histones within the nucleosomes are cross-linked into an octameric complex with formaldehyde. These complexes are sedimented to equilibrium in density gradients and octamer and dioctamer complexes separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. With reversal of the cross-link, the distribution of the individual density-labeled histones in the octamer is determined. Newly synthesized H3 and H4 deposits as a tetramer and are associated with old H2A and H2B. Newly synthesized H2A and H2B deposit as a dimer associated with old H2A, H2B, H3, and H4. The significance of these results with respect to the dynamics of histone interactions in the nucleus is discussed. Control experiments are presented to test for artifactual formation of these complexes during preparative procedures. In addition, reconstitution experiments were performed to demonstrate that the composition of these octameric complexes can be determined from their distribution of density gradients

Polypeptides having beta-glucosidase activity and polynucleotides encoding the same

Science.gov (United States)

Brown, Kimberly; Harris, Paul

2013-12-17

The present invention relates to isolated polypeptides having beta-glucosidase activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides.

Chimeric polypeptides having cellulolytic enhancing activity and polynucleotides encoding same

Science.gov (United States)

Wogulis, Mark; Sweeney, Matthew; Heu, Tia

2017-06-14

The present invention relates to chimeric GH61 polypeptides having cellulolytic enhancing activity. The present invention also relates to polynucleotides encoding the chimeric GH61 polypeptides; nucleic acid constructs, vectors, and host cells comprising the polynucleotides; and methods of using the chimeric GH61 polypeptides.

Global transgenerational gene expression dynamics in two newly synthesized allohexaploid wheat (Triticum aestivum lines

Directory of Open Access Journals (Sweden)

Qi Bao

2012-01-01

Full Text Available Abstract Background Alteration in gene expression resulting from allopolyploidization is a prominent feature in plants, but its spectrum and extent are not fully known. Common wheat (Triticum aestivum was formed via allohexaploidization about 10,000 years ago, and became the most important crop plant. To gain further insights into the genome-wide transcriptional dynamics associated with the onset of common wheat formation, we conducted microarray-based genome-wide gene expression analysis on two newly synthesized allohexaploid wheat lines with chromosomal stability and a genome constitution analogous to that of the present-day common wheat. Results Multi-color GISH (genomic in situ hybridization was used to identify individual plants from two nascent allohexaploid wheat lines between Triticum turgidum (2n = 4x = 28; genome BBAA and Aegilops tauschii (2n = 2x = 14; genome DD, which had a stable chromosomal constitution analogous to that of common wheat (2n = 6x = 42; genome BBAADD. Genome-wide analysis of gene expression was performed for these allohexaploid lines along with their parental plants from T. turgidum and Ae. tauschii, using the Affymetrix Gene Chip Wheat Genome-Array. Comparison with the parental plants coupled with inclusion of empirical mid-parent values (MPVs revealed that whereas the great majority of genes showed the expected parental additivity, two major patterns of alteration in gene expression in the allohexaploid lines were identified: parental dominance expression and non-additive expression. Genes involved in each of the two altered expression patterns could be classified into three distinct groups, stochastic, heritable and persistent, based on their transgenerational heritability and inter-line conservation. Strikingly, whereas both altered patterns of gene expression showed a propensity of inheritance, identity of the involved genes was highly stochastic, consistent with the involvement of diverse Gene Ontology (GO

GLYCOSYLATED YGHJ POLYPEPTIDES FROM ENTEROTOXIGENIC ESCHERICHIA COLI (ETEC)

DEFF Research Database (Denmark)

2017-01-01

The present invention relates to glycosylated YghJ polypeptides from or derived from enterotoxigenic Escherichia coli (ETEC) that are immunogenic. In particular, the present invention relates to compositions or vaccines comprising the polypeptides and their application in immunization, vaccination...

Essential oils-oriented fenvalerate analogues: syntheses, characterization and biological evaluation

International Nuclear Information System (INIS)

Su, H.; Li, H.

2016-01-01

A series of essential oils oriented ester derivatives have been designed, synthesized and characterized based on the skeleton of fenvalerate. The preliminary bioassay results indicated that some of the newly synthesized compounds showed better insecticidal activities against Pyrausta nubilalis and Heliothis armigera than that of the control trans-prallethrin chloride. (author)

UDP-[14C]glucose-labelable polypeptides from pea: Possible components of glucan synthase I activity

International Nuclear Information System (INIS)

Ray, P.M.; Dhugga, K.S.; Gallaghar, S.R.

1989-01-01

A membrane-bound polypeptide doublet of about 40 kD can be rapidly labeled with UDP-[ 14 C]glucose under the assay conditions for glucan synthase I (GS-I). Label seems covalently bound, and chases when unlabeled UDPG is added; it might represent a covalent intermediate in polysaccharide synthesis. Labeling and GS-I activity show several common features: they co-sediment with Golgi membranes in sucrose gradients; they depend similarly on Mg 2+ or Mn 2+ (not Ca 2+ ); they decrease dramatically from stem apex to base, and are higher in epidermis than internal tissue; they show similar sensitivities to several inhibitors. But the doublet still labels after polysaccharide-synthesizing activity has been destroyed by Triton X-100. The doublet polypeptides might be glucosyl tranferases whose ability to transfer glucose units to a glucan chain is detergent-sensitive, but to accept glucose from UDPG is not; or they might be detergent-insensitive primary glucose acceptors, from which a distinct, detergent-sensitive transferase(s) move(s) these units to glucan chains

Multi-wavelength spectrophotometric determination of acidity constant of some newly synthesized Schiff bases and their QSPR study

Science.gov (United States)

Hemmateenejad, Bahram; Emami, Leila; Sharghi, Hashem

2010-01-01

The acidity constants of some newly synthesized Schiff base derivatives were determined by hard-model based multivariate data analysis of the spectrophotometric data in the course of pH-metric titration in 50% (v/v) methanol-water binary solvent. The employed data analysis method was also able to extract the pure spectra and pH-dependent concentration profiles of the acid-base species. The molecules that possess different substituents (both electron donating and withdrawing) on the ortho-, meta- and para-positions of one of the phenyl ring showed variable acidity constants ranging from 8.77 to 11.07 whereas the parent molecule had an acidity constant of 10.25. To investigate the quantitative effects of changing of substitution pattern on the acidity constant, a quantitative structure-property relation analysis was conducted using substituent constants and molecular descriptor. Some models with high statistical quality (measured by cross-validation Q2) were obtained. It was found that the acidity constant of the studied molecules in the methanol-water mixed solvent not only is affected by electronic features of the solutes but also by the lipophilic interaction between methanol part of solvent and the deprotonated solutes.

Tunable drug loading and release from polypeptide multilayer nanofilms

Science.gov (United States)

Jiang, Bingbing; Li, Bingyun

2009-01-01

Polypeptide multilayer nanofilms were prepared using electrostatic layer-by-layer self-assembly nanotechnology. Small charged drug molecules (eg, cefazolin, gentamicin, and methylene blue) were loaded in polypeptide multilayer nanofilms. Their loading and release were found to be pH-dependent and could also be controlled by changing the number of film layers and drug incubation time, and applying heat-treatment after film formation. Antibioticloaded polypeptide multilayer nanofilms showed controllable antibacterial properties against Staphylococcus aureus. The developed biodegradable polypeptide multilayer nanofilms are capable of loading both positively- and negatively-charged drug molecules and promise to serve as drug delivery systems on biomedical devices for preventing biomedical device-associated infection, which is a significant clinical complication for both civilian and military patients. PMID:19421369

Formation of newly synthesized adeno-associated virus capsids in the cell nucleus.

Science.gov (United States)

Bell, Peter; Vandenberghe, Luk H; Wilson, James M

2014-06-01

Adeno-associated virus (AAV) particles inside the nucleus of a HEK 293 cell are shown by electron microscopy. Cells have been triple-transfected for vector production and were analyzed for capsid formation three days later. Newly assembled particle are visible as seemingly unstructured conglomerates or crystal-like arrays.

Star-Shaped Polypeptides: Synthesis and Opportunities for Delivery of Therapeutics.

Science.gov (United States)

Byrne, Mark; Murphy, Robert; Kapetanakis, Antonios; Ramsey, Joanne; Cryan, Sally-Ann; Heise, Andreas

2015-09-17

Significant advances in the synthesis of polypeptides by N-carboxyanhydride (NCA) polymerisation over the last decade have enabled the design of advanced polypeptide architectures such as star-shaped polypeptides. These materials combine the functionality offered by amino acids with the flexibility of creating stable nanoparticles with adjustable cargo space for therapeutic delivery. This review highlights recent advances in the synthesis of star polypeptides by NCA polymerisation followed by a critical review of the applications of this class of polymer in the delivery of therapeutic agents. This includes examples of traditional small-molecule drugs as well as the emerging class of biologics such as genetic therapeutics (gene delivery). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Proteolytic processing of poliovirus polypeptides: antibodies to polypeptide P3-7c inhibit cleavage at glutamine-glycine pairs

International Nuclear Information System (INIS)

Hanecak, R.; Semler, B.L.; Anderson, C.W.; Wimmer, E.

1982-01-01

Proteolytic processing of poliovirus polypeptides was examined by the addition of antibodies directed against the viral proteins P3-7c and P2-X to a cell-free translation extract prepared from infected HeLa cells. Antisera to P3-7c specifically inhibited in vitro processing at Gln-Gly pairs. Partial amino acid sequence analysis revealed a second Tyr-Gly pair that is utilized in protein processing. Neither Tyr-Gly cleavage is affected by antibody to P3-7C. Anti-P3-7c antibodies react not only with P3-7c but also with P3-6a and P3-2, two viral polypeptides NH 2 -coterminal with P3-7c. Preimmune and anti-P2-X antibodies had no effect on the processing of poliovirus proteins in vitro. The authors conclude that the activity responsible for processing poliovirus polypeptides at Gln-Gly pairs resides in the primary structure of P3-7c and not in P2-X

Fibronectin-synthesizing activity of free and membrane-bound polyribosomes from human embryonic fibroblasts and chick embryos

International Nuclear Information System (INIS)

Belkin, V.M.; Volodarskaya, S.M.

1986-01-01

The fibronectin-synthesizing activity of membrane-bound and free polyribosomes in a cell-free system was studied using immunochemical methods. It was found that fibronectin biosynthesis on membrane-bound polyribosomes from human embryonic fibroblasts accounts for 4.9% and those from 10-day-old chick embryos for 1.1% of the total amount of newly synthesized proteins, whereas on free polyribosomes it is 1.0 and 0.3%, respectively. Fibronectin monomers with a molecular weight of 220,000 were found only in the material of the cell-free system containing heavy fractions of membrane-bound polyribosomes newly synthesized in the presence of spermidine. Thus, it was shown that fibronectin is synthesized primarily on membrane-bound polyribosomes

Baculovirus replication: characterization of DNA and proteins synthesized by a nuclear polyhedrosis virus of Lymantria dispar, the gypsy moth, in a homologous cell line

International Nuclear Information System (INIS)

McClintock, J.T.

1985-01-01

A multiple-embedded nuclear polyhedrosis virus (NPV) of the gypsy moth, Lymantria dispar (LdMNPV), is used for biological control. However, LdMNPV has low natural virulence and a long infection cycle in relation to other NPVs. Therefore, the replicative cycle of LdMNPV was investigated using a homologous cell line, IPLB-LD-652Y. Based on analyses of virus growth curves LdMNPV nonoccluded virus and polyhedral inclusion bodies appeared approximately 20 and 50 hr postinfection (p.i.), respectively. LdMNPV polypeptides, identified by autoradiography of [ 35 S]-methionine labeled fractions in SDS-PAGE, were synthesized in sequential phases: (1) an early α phase of replication (4 polypeptides from 4 to 12 hr p.i.), (2) an intermediate β phase (20 polypeptides from 12 to 24 hr p.i.), and a late γ phase (4 polypeptides from 24 to 28 hr p.i.). In infected cells at least four polypeptides were post-translational cleaved and/or modified. Pulse-labeling with [ 3 H]-mannose, [ 3 H]-N-acetyl-glucosamine or [ 32 P]-monosodium phosphate revealed several viral polypeptides which were glycosylated and/or phosphorylated. DNA:DNA dot hybridization experiments suggested that LdMNPV DNA synthesis was initiated between 12 to 16 hr p.i., increasing significantly thereafter

UV cross-linking of polypeptides associated with 3'-terminal exons

International Nuclear Information System (INIS)

Stolow, D.T.; Berget, S.M.

1990-01-01

Association of nuclear proteins with chimeric vertebrate precursor RNAs containing both polyadenylation signals and an intron was examined by UV cross-linking. One major difference in cross-linking pattern was observed between this chimeric precursor RNA and precursors containing only polyadenylation or splicing signals. The heterogeneous nuclear ribonucleoprotein (hnRNP) polypeptide C cross-linked strongly to sequences downstream of the A addition site in polyadenylation precursor RNA containing only the polyadenylation signal from the simian virus 40 (SV40) late transcription unit. In contrast, the hnRNP C polypeptide cross-linked to chimeric RNA containing the same SV40 late poly(A) cassette very poorly, at a level less than 5% of that observed with the precursor RNA containing just the poly(A) site. Observation that cross-linking of the hnRNP C polypeptide to elements within the SV40 late poly(A) site was altered by the presence of an upstream intron suggests differences in the way nuclear factors associate with poly(A) sites in the presence and absence of an upstream intron. Cross-linking of C polypeptide to chimeric RNA increased with RNAs mutated for splicing or polyadenylation consensus sequences and under reaction conditions (high magnesium) that inhibited polyadenylation. Furthermore, cross-linking of hnRNP C polypeptide to precursors containing just the SV40 late poly(A) site was eliminated in the presence of competing poly(U); polyadenylation, however, was unaffected. Correlation of loss of activity with high levels of hnRNP C polypeptide cross-linking raises questions about the specificity of the interaction between the hnRNP C polypeptide and polyadenylation precursor RNAs in vitro

Specific proteins synthesized during the viral lytic cycle in vaccinia virus-infected HeLa cells: analysis by high-resolution, two-dimensional gel electrophoresis

International Nuclear Information System (INIS)

Carrasco, L.; Bravo, R.

1986-01-01

The proteins synthesized in vaccinia-infected HeLa cells have been analyzed at different times after infection by using two-dimensional gel electrophoresis. Vaccinia-infected cells present up to 198 polypeptides (138 acidic, isoelectric focusing; 60 basic, nonequilibrium pH gradient electrophoresis) not detected in control cells. Cells infected in the presence of cycloheximide show 81 additional polypeptides after cycloheximide removal, resulting in a total estimate of 279 proteins induced after vaccinia infection. The glycoproteins made at various time postinfection were also analyzed. At least 13 proteins labeled with [ 3 H]glucosamine were detected in vaccinia-infected HeLa cells

Vasoactive intestinal polypeptide induces glycogenolysis in mouse cortical slices: a possible regulatory mechanism for the local control of energy metabolism.

OpenAIRE

Magistretti, P J; Morrison, J H; Shoemaker, W J; Sapin, V; Bloom, F E

1981-01-01

Mouse cerebral cortex slices will synthesize [3H]glycogen in vitro. Vasoactive intestinal polypeptide (VIP) stimulates the enzymatic breakdown of this [3H]glycogen. The concentration giving 50% of maximum effectiveness (EC50) is 26 nM. Under the same experimental conditions norepinephrine also induces a concentration-dependent [3H]glycogen hydrolysis with an EC50 of 500 nM. The effect of VIP is not mediated by the release of norepinephrine because it is not blocked by the noradrenergic antago...

Laminin, a noncollagenous component of epithelial basement membranes synthesized by a rat yolk sac tumor

DEFF Research Database (Denmark)

Wewer, U; Albrechtsen, R; Ruoslahti, E

1981-01-01

Laminin, a glycoprotein antigenically similar or identical to a component of epithelial basement membranes, was identified as a major component of the abundant extracellular matrix synthesized by an experimentally induced rat yolk sac tumor. Immunocytochemical staining revealed laminin in cultured...... polypeptides with molecular weights of approximately 200,000 and 400,000. These comigrated with the polypeptides of mouse laminin isolated previously. The yolk sac tumor tissue grown in vivo contained laminin in the tumor cells and in the extracellular material as evidenced by immunofluorescence...... membranes in rat tissues in a manner indistinguishable from antilaminin. The presence of laminin in rat yolk sac cells, the presumed origin of our yolk sac tumor, was studied in some detail. Laminin was found to be present in normal cells of the visceral as well as the parietal yolk sac layer...

Biochemical map of polypeptides specified by foot-and-mouth disease virus.

OpenAIRE

Grubman, M J; Robertson, B H; Morgan, D O; Moore, D M; Dowbenko, D

1984-01-01

Pulse-chase labeling of foot-and-mouth disease virus-infected bovine kidney cells revealed stable and unstable viral-specific polypeptides. To identify precursor-product relationships among these polypeptides, antisera against a number of structural and nonstructural viral-specific polypeptides were used. Cell-free translations programmed with foot-and-mouth disease virion RNA or foot-and-mouth disease virus-infected bovine kidney cell lysates, which were shown to contain almost identical pol...

Polypeptide based hydrogels

OpenAIRE

Hanay, Saltuk

2018-01-01

There is a need for biocompatible, biodegradable, 3-D printable and stable hydrogels especially in the areas of tissue engineering, drug delivery, bio-sensing technologies and antimicrobial coatings. The main aim of this Ph.D. work was to fabricate polypeptide based hydrogel which may find a potential application in those fields. Focusing on tyrosine or tryptophan-containing copolypeptides prepared by NCarboxyanhydride (NCA) polymerizations, three different crosslinking strategies have been t...

Fabrication of copper-selective PVC membrane electrode based on newly synthesized copper complex of Schiff base as carrier

Directory of Open Access Journals (Sweden)

Sulekh Chandra

2016-09-01

Full Text Available The newly synthesized copper(II complex of Schiff base p-hydroxyacetophenone semicarbazone was explored as neutral ionophore for the fabrication of poly(vinylchloride (PVC based membrane electrode selective to Cu(II ions. The electrode shows a Nernstian slope of 29.8 ± 0.3 mV/decade with improved linear range of 1.8 × 10−7 to 1.0 × 10−1 M, comparatively lower detection limit 5.7 × 10−8 M between pH range of 2.0–8.0, giving a relatively fast response within 5s and can be used for at least 16 weeks without any divergence in potential. The selectivity coefficient was calculated using the fixed interference method (FIM. The electrode can also be used in partially non-aqueous media having up to 25% (v/v methanol, ethanol or acetone content with no significant change in the value of slope or working concentration range. It was successfully applied for the direct determination of copper content in water and tea samples with satisfactory results. The electrode has been used in the potentiometric titration of Cu2+ with EDTA.

Simultaneous Polymerization and Polypeptide Particle Production via Reactive Spray-Drying.

Science.gov (United States)

Glavas, Lidija; Odelius, Karin; Albertsson, Ann-Christine

2016-09-12

A method for producing polypeptide particles via in situ polymerization of N-carboxyanhydrides during spray-drying has been developed. This method was enabled by the development of a fast and robust synthetic pathway to polypeptides using 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as an initiator for the ring-opening polymerization of N-carboxyanhydrides. The polymerizations finished within 5 s and proved to be very tolerant toward impurities such as amino acid salts and water. The formed particles were prepared by mixing the monomer, N-carboxyanhydride of l-glutamic acid benzyl ester (NCAGlu) and the initiator (DBU) during the atomization process in the spray-dryer and were spherical with a size of ∼1 μm. This method combines two steps; making it a straightforward process that facilitates the production of polypeptide particles. Hence, it furthers the use of spray-drying and polypeptide particles in the pharmaceutical industry.

Synthesis of Zeolite from Fly Ash and Removal of Heavy Metal Ions from Newly Synthesized Zeolite

OpenAIRE

Solanki, Parag; Gupta, Vikal; Kulshrestha, Ruchi

2010-01-01

Coal fly ash was used to synthesize X-type zeolite by alkali fusion followed by hydrothermal treatment. Characteristics of the various Fly ash samples were carried out. Coal proximate analysis was done. Batch experiment was carried out for the adsorption of some heavy metal ions on to synthesized Zeolite. The cost of synthesized zeolite was estimated to be almost one-fifth of that of commercial 13X zeolite available in the market.

99mTc-HYNIC-derivatized ternary ligand complexes for 99mTc-labeled polypeptides with low in vivo protein binding

International Nuclear Information System (INIS)

Ono, Masahiro; Arano, Yasushi; Mukai, Takahiro; Fujioka, Yasushi; Ogawa, Kazuma; Uehara, Tomoya; Saga, Tsuneo; Konishi, Junji; Saji, Hideo

2001-01-01

6-Hydrazinopyridine-3-carboxylic acid (HYNIC) is a representative agent used to prepare technetium-99m ( 99m Tc)-labeled polypeptides with tricine as a coligand. However, 99m Tc-HYNIC-labeled polypeptides show delayed elimination rates of the radioactivity not only from the blood but also from nontarget tissues such as the liver and kidney. In this study, a preformed chelate of tetrafluorophenol (TFP) active ester of [ 99m Tc](HYNIC)(tricine)(benzoylpyridine: BP) ternary complex was synthesized to prepare 99m Tc-labeled polypeptides with higher stability against exchange reactions with proteins in plasma and lysosomes using the Fab fragment of a monoclonal antibody and galactosyl-neoglycoalbumin (NGA) as model polypeptides. When incubated in plasma, [ 99m Tc](HYNIC-Fab)(tricine)(BP) showed significant reduction of the radioactivity in high molecular weight fractions compared with [ 99m Tc](HYNIC-Fab)(tricine) 2. When injected into mice, [ 99m Tc](HYNIC-NGA)(tricine)(BP) was metabolized to [ 99m Tc](HYNIC-lysine)(tricine)(BP) in the liver with no radioactivity detected in protein-bound fractions in contrast to the observations with [ 99m Tc](HYNIC-NGA)(tricine) 2. In addition, [ 99m Tc](HYNIC-NGA)(tricine)(BP) showed significantly faster elimination rates of the radioactivity from the liver as compared with [ 99m Tc](HYNIC-NGA)(tricine) 2. Similar results were observed with 99m Tc-labeled Fab fragments where [ 99m Tc](HYNIC-Fab)(tricine)(BP) exhibited significantly faster elimination rates of the radioactivity not only from the blood but also from the kidney. These findings indicated that conjugation of [ 99m Tc](HYNIC)(tricine)(BP) ternary ligand complex to polypeptides accelerated elimination rates of the radioactivity from the blood and nontarget tissues due to low binding of the [ 99m Tc](HYNIC)(tricine)(BP) complex with proteins in the blood and in the lysosomes. Such characteristics would render the TFP active ester of [ 99m Tc](HYNIC)(tricine)(BP) complex

Unstable structure of ribosomal particles synthesized in. gamma. -irradiated Escherichia coli

Energy Technology Data Exchange (ETDEWEB)

Fujita, H; Morita, K [National Inst. of Radiological Sciences, Chiba (Japan)

1975-06-01

Stability of Escherichia coli ribosomes newly synthesized after ..gamma..-irradiation was compared with that of normal ribosomes. The ribosomal particles around 70-S synthesized in irradiated cells were more sensitive to digestion by pancreatic ribonuclease A. A larger number of the salt-unstable '50-S' precursor particles existed in the extract from irradiated cells than in the extract from unirradiated cells. These facts suggest that ribosomal particles, synthesized during an earlier stage in irradiated cells, maintain an incomplete structure even though they are not distinguishable from normal ribosomes by means of sucrose density-gradient centrifugation.

Induction of protein body formation in plant leaves by elastin-like polypeptide fusions

Directory of Open Access Journals (Sweden)

Joensuu Jussi J

2009-08-01

Full Text Available Abstract Background Elastin-like polypeptides are synthetic biopolymers composed of a repeating pentapeptide 'VPGXG' sequence that are valuable for the simple non-chromatographic purification of recombinant proteins. In addition, elastin-like polypeptide fusions have been shown to enhance the accumulation of a range of different recombinant proteins in plants, thus addressing the major limitation of plant-based expression systems, which is a low production yield. This study's main objectives were to determine the general utility of elastin-like polypeptide protein fusions in various intracellular compartments and to elucidate elastin-like polypeptide's mechanism of action for increasing recombinant protein accumulation in the endoplasmic reticulum of plants. Results The effect of elastin-like polypeptide fusions on the accumulation of green fluorescent protein targeted to the cytoplasm, chloroplasts, apoplast, and endoplasmic reticulum was evaluated. The endoplasmic reticulum was the only intracellular compartment in which an elastin-like polypeptide tag was shown to significantly enhance recombinant protein accumulation. Interestingly, endoplasmic reticulum-targeted elastin-like polypeptide fusions induced the formation of a novel type of protein body, which may be responsible for elastin-like polypeptide's positive effect on recombinant protein accumulation by excluding the heterologous protein from normal physiological turnover. Although expressed in the leaves of plants, these novel protein bodies appeared similar in size and morphology to the prolamin-based protein bodies naturally found in plant seeds. The elastin-like polypeptide-induced protein bodies were highly mobile organelles, exhibiting various dynamic patterns of movement throughout the cells, which were dependent on intact actin microfilaments and a functional actomyosin motility system. Conclusion An endoplasmic reticulum-targeted elastin-like polypeptide fusion approach

Basal serum pancreatic polypeptide is dependent on age and gender in an adult population

DEFF Research Database (Denmark)

Brimnes Damholt, M; Rasmussen, B K; Hilsted, L

1997-01-01

This study is the first epidemiologically based study of basal levels of serum pancreatic polypeptide (s-PP). The basal level of serum PP has become a field of interest mainly due to the role of PP as an endocrine tumour marker, and as a marker of pancreatic neuroendocrine function after pancreas...... a monospecific radioimmunoassay. Fasting serum pancreatic polypeptide depended on age and gender. The results demonstrated that fasting pancreatic polypeptide levels increase exponentially with age. Fitted separately for each sex, basal serum pancreatic polypeptide was found to increase by approximately 3% per...... reports on the fasting levels of serum pancreatic polypeptide are most likely due to lack of adjustment for age and gender. Thus, variation due to age and gender should be considered in evaluating fasting levels of serum pancreatic polypeptide. Whether similar considerations are important when evaluating...

Amphotericin B-conjugated polypeptide hydrogels as a novel innovative strategy for fungal infections

Science.gov (United States)

Shu, Chang; Li, Tengfei; Yang, Wen; Li, Duo; Ji, Shunli; Ding, Li

2018-03-01

The present work is focused on the design and development of novel amphotericin B (AmB)-conjugated biocompatible and biodegradable polypeptide hydrogels to improve the antifungal activity. Using three kinds of promoting self-assembly groups (2-naphthalene acetic acid (Nap), naproxen (Npx) and dexamethasone (Dex)) and polypeptide sequence (Phe-Phe-Asp-Lys-Tyr, FFDKY), we successfully synthesized the Nap-FFDK(AmB)Y gels, Npx-FFDK(AmB)Y gels and Dex-FFDK(AmB)Y gels. The AmB-conjugated hydrogelators are highly soluble in different aqueous solutions. The cryo-transmission electron microscopy and scanning electron microscopy micrographs of hydrogels afford nanofibres with a width of 20-50 nm. Powder X-ray diffraction analyses demonstrate that the crystalline structures of the AmB and Dex are changed into amorphous structures after the formation of hydrogels. Circular dichroism spectra of the solution of blank carriers and the corresponding drug deliveries further help elucidate the molecular arrangement in gel phase, indicating the existence of turn features. The in vitro drug releases suggest that the AmB-conjugated hydrogels are suitable as drug-controlled release vehicles for hydrophobic drugs. The antifungal effect of AmB-conjugated hydrogels significantly exhibits the antifungal activity against Candida albicans. The results of the present study indicated that the AmB-conjugated hydrogels are suitable carriers for poorly water soluble drugs and for enhancement of therapeutic efficacy of antifungal drugs.

Polypeptide synthesis in alphavirus-infected aedes albopictus cells during the establishment of persistent infection

International Nuclear Information System (INIS)

Richardson, M.A.; Boulton, R.W.; Raghow, R.S.; Dalgarno, L.

1980-01-01

Polypeptide synthesis was examined in mosquito cells during the establishment of a persistent infection with two alphaviruses, Ross River virus (RRV) and Semliki Forest virus (SFV), and in vertebrate cells cytopathically-infected with the same viruses. In Aedes albopictus cells, RRV reached peak titres at 34-48 hours p.i. At 12 hours 85 per cent of cells assayed as infected by infective centre assay; by 48 hours when persistence was established, virus production was reduced and <5 per cent of cells assayed as infected. There was not shutdown of host polypeptide synthesis during infection. Viral polypeptide synthesis was maximal between 10 and 24 hours p.i. The major viral polypeptides labelled were nucleocapsid protein and envelope protein(s).The precursor polypeptide p95 which was prominent in infected BHK cells was not detected in mosquito cells. Similar results were obtained on SFV infection. During the establishment of persistence there was a coordinate decline in the synthesis of RRV polypeptides, reaching undetectable levels by 72 hours p.i. Subculturing persistently-infected cells led to a small increase in viral polypeptide synthesis and virus titre. In contrast, during RRV growth in BHK cells host protein synthesis was severely inhibited and by 9-11 hours p.i. virus-specific polypeptide synthesis represented more than 90 per cent of total protein synthetic activity. (author)

A de novo designed 11 kDa polypeptide: model for amyloidogenic intrinsically disordered proteins.

Science.gov (United States)

Topilina, Natalya I; Ermolenkov, Vladimir V; Sikirzhytski, Vitali; Higashiya, Seiichiro; Lednev, Igor K; Welch, John T

2010-07-01

A de novo polypeptide GH(6)[(GA)(3)GY(GA)(3)GE](8)GAH(6) (YE8) has a significant number of identical weakly interacting beta-strands with the turns and termini functionalized by charged amino acids to control polypeptide folding and aggregation. YE8 exists in a soluble, disordered form at neutral pH but is responsive to changes in pH and ionic strength. The evolution of YE8 secondary structure has been successfully quantified during all stages of polypeptide fibrillation by deep UV resonance Raman (DUVRR) spectroscopy combined with other morphological, structural, spectral, and tinctorial characterization. The YE8 folding kinetics at pH 3.5 are strongly dependent on polypeptide concentration with a lag phase that can be eliminated by seeding with a solution of folded fibrillar YE8. The lag phase of polypeptide folding is concentration dependent leading to the conclusion that beta-sheet folding of the 11-kDa amyloidogenic polypeptide is completely aggregation driven.

Radiolysis of polypeptide

International Nuclear Information System (INIS)

Ogura, Isao; Nakamura, Katsuichi; Tanaka, Hiroshi; Takahashi, Katsuhiro; Ozaki, Makoto

1981-01-01

Almost the same results were obtained from the additional dipeptide, Gly-DL-Ala and DL-Ala-DL-Phe, by the γ-irradiation as previous report. Tri and tetrapeptide consisted of the same amino acid signified good stability than the others. Every polypeptide composed from sulfur contained amino acid exhaled the smell of hydrogen sulfide by the irradiation. It seemed that the stability by the difference of position of amino group in amino acid increased in order α, β, γ ... amino acid and that by the existence of hydroxyl group became smaller. (author)

The Research on the Impact of Maca Polypeptide on Sport Fatigue.

Science.gov (United States)

Miao, Hua

2015-01-01

In order to study the effect of maca polypeptide on sport fatigue, this paper selected 40 male mice, and they were randomly divided into group A, B, C and D. group A, B and C were fed food with different concentrations of maca polypeptide, and group D was control group. After two weeks of feeding, measured physiological indexes of mice, including blood glucose, urea nitrogen and creatinine. At last gived the experimental results, as well as the analysis. Experimental results show that maca polypeptide can improve the ability of anti-fatigue mice, and in a certain concentration range, the higher the concentration, the better the resistance to fatigue.

High plasma levels of islet amyloid polypeptide in young with new-onset of type 1 diabetes mellitus.

Directory of Open Access Journals (Sweden)

Johan F Paulsson

Full Text Available AIMS/HYPOTHESIS: Islet amyloid polypeptide (IAPP is a beta cell hormone secreted together with insulin upon glucose stimulation. IAPP participates in normal glucose regulation, but IAPP is also known for its ability to misfold and form islet amyloid. Amyloid fibrils form through smaller cell toxic intermediates and deposited amyloid disrupts normal islet architecture. Even though IAPP and amyloid formation are much discussed in type 2 diabetes, our aim was to study the significance of IAPP in type 1 diabetes. RESULTS: Plasma IAPP levels in children and adolescents with newly diagnosed type 1 diabetes (n = 224 were analysed and concentrations exceeding 100 pmol/L (127.2-888.7 pmol/L were found in 11% (25/224. The IAPP increase did not correlate with C-peptide levels. CONCLUSIONS/INTERPRETATION: Plasma levels of IAPP and insulin deviate in a subpopulation of young with newly-diagnosed type 1 diabetes. The determined elevated levels of IAPP might increase the risk for IAPP misfolding and formation of cell toxic amyloid in beta cells. This finding add IAPP-aggregation to the list over putative pathological factors causing type 1 diabetes.

Molecular Dynamics Simulation of Cholera Toxin A-1 Polypeptide

Directory of Open Access Journals (Sweden)

Badshah Syed Lal

2016-01-01

Full Text Available A molecular dynamics (MD simulation study of the enzymatic portion of cholera toxin; cholera toxin A-1 polypeptide (CTA1 was performed at 283, 310 and 323 K. From total energy analysis it was observed that this toxin is stable thermodynamically and these outcomes were likewise confirmed by root mean square deviations (RMSD investigations. The Cα root mean square fluctuation (RMSF examinations revealed that there are a number of residues inside CTA1, which can be used as target for designing and synthesizing inhibitory drugs, in order to inactivate cholera toxin inside the human body. The fluctuations in the radius of gyration and hydrogen bonding in CTA1 proved that protein unfolding and refolding were normal routine phenomena in its structure at all temperatures. Solvent accessible surface area study identified the hydrophilic nature of the CTA1, and due to this property it can be a potential biological weapon. The structural identification (STRIDE algorithm for proteins was successfully used to determine the partially disordered secondary structure of CTA1. On account of this partially disordered secondary structure, it can easily deceive the proteolytic enzymes of the endoplasmic reticulum of host cells.

Tuning Ice Nucleation with Supercharged Polypeptides

NARCIS (Netherlands)

Yang, Huige; Ma, Chao; Li, Kaiyong; Liu, Kai; Loznik, Mark; Teeuwen, Rosalie; van Hest, Jan C. M.; Zhou, Xin; Herrmann, Andreas; Wang, Jianjun

2016-01-01

Supercharged unfolded polypeptides (SUPs) are exploited for controlling ice nucleation via tuning the nature of charge and charge density of SUPs. The results show that positively charged SUPs facilitate ice nucleation, while negatively charged ones suppress it. Moreover, the charge density of the

Investigation of formation constant of complex of a new synthesized ...

African Journals Online (AJOL)

The complex formation between a newly synthesized tripodal ligand and the cation Cu2+ in water and surfactant media was studied spectrophotometrically using rank annihilation factor analysis (RAFA). According to molar ratio data the stoichiometry of complexation between the ligand and the cation Cu2+ was 1:1.

Newly synthesized bis-benzimidazole compound 8 induces apoptosis, autophagy and reactive oxygen species generation in HeLa cells.

Science.gov (United States)

Chu, Naying; Yao, Guodong; Liu, Yuan; Cheng, Maosheng; Ikejima, Takashi

2016-09-01

Compound 8 (C8) is a newly synthesized bis-benzimidazole derivative and exerts significant anti-tumor activity in vitro. Previous studies demonstrated that C8 induced apoptosis and autophagy in human promyelocytic leukemia HL60 cells. However, cytotoxicity study on human peripheral blood mononuclear cells (hPBMC) showed that C8 exhibited less toxicity in normal cells. In this study, the molecular mechanism of C8 on human cervical carcinoma HeLa cells was investigated. The results showed that C8 inhibited the growth of HeLa cells and triggered both apoptotic and autophagic cell death. Subsequent experiment also indicated that reactive oxygen species (ROS) generation was induced in C8-treated HeLa cells. Since ROS scavenger decreased the ratio of apoptotic and autophagic cells, ROS generation contributed to C8-induced apoptosis and autophagy. Furthermore, inhibitors of apoptosis and autophagy also reduced ROS generation, respectively. Autophagy inhibition increased cell growth compared to C8-treated group and attenuated apoptotic cell death, indicating that C8-induced autophagy promoted apoptosis for cell death. However, the percentage of autophagic cells was enhanced when limiting apoptosis process. Taken together, C8 induced ROS-mediated apoptosis and autophagy in HeLa cells, autophagy promoted apoptosis but the former was antagonized by the latter. The data also gave us a new perspective on the anti-tumor effect of C8. Copyright © 2016 Elsevier Ltd. All rights reserved.

The chaperonin of the archaeon Sulfolobus solfataricus is an RNA-binding protein that participates in ribosomal RNA processing.

OpenAIRE

Ruggero, D; Ciammaruconi, A; Londei, P

1998-01-01

The 60 kDa molecular chaperones (chaperonins) are high molecular weight protein complexes having a characteristic double-ring toroidal shape; they are thought to aid the folding of denatured or newly synthesized polypeptides. These proteins exist as two functionally similar, but distantly related families, one comprising the bacterial and organellar chaperonins and another (the so-called CCT-TRiC family) including the chaperonins of the archaea and the eukaryotes. Although some evidence exist...

A fluorescence-based method for direct measurement of submicrosecond intramolecular contact formation in biopolymers: an exploratory study with polypeptides.

Science.gov (United States)

Hudgins, Robert R; Huang, Fang; Gramlich, Gabriela; Nau, Werner M

2002-01-30

A fluorescent amino acid derivative (Fmoc-DBO) has been synthesized, which contains 2,3-diazabicyclo[2.2.2]oct-2-ene (DBO) as a small, hydrophilic fluorophore with an extremely long fluorescence lifetime (325 ns in H2O and 505 ns in D2O under air). Polypeptides containing both the DBO residue and an efficient fluorescence quencher allow the measurement of rate constants for intramolecular end-to-end contact formation. Bimolecular quenching experiments indicated that Trp, Cys, Met, and Tyr are efficient quenchers of DBO (k(q) = 20, 5.1, 4.5, and 3.6 x 10(8) M(-1) x s(-1) in D2O), while the other amino acids are inefficient. The quenching by Trp, which was selected as an intrinsic quencher, is presumed to involve exciplex-induced deactivation. Flexible, structureless polypeptides, Trp-(Gly-Ser)n-DBO-NH2, were prepared by standard solid-phase synthesis, and the rates of contact formation were measured through the intramolecular fluorescence quenching of DBO by Trp with time-correlated single-photon counting, laser flash photolysis, and steady-state fluorometry. Rate constants of 4.1, 6.8, 4.9, 3.1, 2.0, and 1.1 x 10(7) s(-1) for n = 0, 1, 2, 4, 6, and 10 were obtained. Noteworthy was the relatively slow quenching for the shortest peptide (n = 0). The kinetic data are in agreement with recent transient absorption studies of triplet probes for related peptides, but the rate constants are significantly larger. In contrast to the flexible structureless Gly-Ser polypeptides, the polyproline Trp-Pro4-DBO-NH2 showed insignificant fluorescence quenching, suggesting that a high polypeptide flexibility and the possibility of probe-quencher contact is essential to induce quenching. Advantages of the new fluorescence-based method for measuring contact formation rates in biopolymers include high accuracy, fast time range (100 ps-1 micros), and the possibility to perform measurements in water under air.

Expression of ribosomal genes in pea cotyledons at the initial stages of germination

International Nuclear Information System (INIS)

Gumilevskaya, N.A.; Chumikhina, L.V.; Akhmatova, A.T.; Kretovich, V.L.

1986-01-01

The time of appearance of newly synthesized rRNAs and ribosomal proteins (r-proteins) in the ribosomes of pea cotyledons (Pisum sativum L.) during germination was investigated. The ribosomal fraction was isolated and analyzed according to the method of germination of the embryo in the presence of labeled precursors or after pulse labeling of the embryos at different stages of germination. For the identification of newly synthesized rRNAs in the ribosomes we estimated the relative stability of labeled RNAs to the action of RNase, the sedimentation rate, the ability to be methylated in vivo in the presence of [ 14 C]CH 3 -methionine, and the localization in the subunits of dissociated ribosomes. The presence of newly synthesized r-proteins in the ribosomes was judged on the basis of the electrophoretic similarity in SDS-disc electrophoresis of labeled polypeptides of purified ribosome preparations and of genuine r-proteins, as well as according to the localization of labeled proteins in the subunits of the dissociated ribosomes. It was shown that the expression of the ribosomal genes in highly specialized cells of pea cotyledons that have completed their growth occurs at very early stages of germination

Newly synthesized MgAl2Ge2: A first-principles comparison with its silicide and carbide counterparts

Science.gov (United States)

Tanveer Karim, A. M. M.; Hadi, M. A.; Alam, M. A.; Parvin, F.; Naqib, S. H.; Islam, A. K. M. A.

2018-06-01

Using plane-wave pseudopotential density functional theory (DFT), the first-principle calculations are performed to investigate the structural aspects, mechanical behaviors and electronic features of the newly synthesized CaAl2Si2-prototype intermetallic compound, MgAl2Ge2 for the first time and the results are compared with those calculated for its silicide and carbide counterparts MgAl2Si2 and MgAl2C2. The calculated lattice constants agree fairly well with their corresponding experimental values. The estimated elastic tensors satisfy the mechanical stability conditions for MgAl2Ge2 along with MgAl2Si2 and MgAl2C2. The level of elastic anisotropy increases following the sequence of X-elements Ge → Si → C. MgAl2Ge2 and MgAl2Si2 are expected to be ductile and damage tolerant, while MgAl2C2 is a brittle one. MgAl2Ge2 and MgAl2Si2 should exhibit better thermal shock resistance and low thermal conductivity and accordingly these can be used as thermal barrier coating (TBC) materials. The Debye temperature of MgAl2Ge2 is lowest among three intermetallic compounds. MgAl2Ge2 and MgAl2Si2 should exhibit metallic conductivity; while the dual characters of weak-metals and semiconductors are expected for MgAl2C2. The values of theoretical Vickers hardness for MgAl2Ge2, MgAl2Si2, and MgAl2C2 are 3.3, 2.7, and 7.7 GPa, respectively, indicating that these three intermetallics are soft and easily machinable.

Ultrastructural and biochemical detection of biotin and biotinylated polypeptides in Schistosoma mansoni

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Santos P.R.P.

1997-01-01

Full Text Available Biotinylation is proposed for the identification of surface proteins in Schistosoma mansoni using the streptavidin-HRP conjugate for the detection of labeled polypeptides. However, control samples also showed several endogenous biotinylated polypeptides. In an attempt to determine the possibility of nonspecific binding between the streptavidin-HRP conjugate and polypeptides from S. mansoni, the conjugate was blocked with biotinamidecaproate-N-hydroxysuccinimide ester (BcapNHS before biotin-streptavidin blotting. No bands were detected on the nitrocellulose sheet, demonstrating the specific recognition of biotin by the streptavidin present in the conjugate. Whole cercariae and cercarial bodies and tails showed several endogenous biotinylated polypeptides. The biotin concentration was 13 µg/190,000 cercariae. Adult worms presented less endogenous biotinylated polypeptides than cercariae. These results may be due to changes in the environment from aerobic to anaerobic conditions when cercarial bodies (schistosomula are transformed into adult worms and a decrease in CO2 production may occur. Cercariae, cercarial bodies and adult male worms were examined by transmission electron microscopy employing an avidin-colloidal gold conjugate for the detection of endogenous biotin. Gold particles were distributed mainly on the muscle fibers, but dispersed granules were observed in the tegument, mitochondria and cytosol. The discovery of endogenous biotin in S. mansoni should be investigated in order to clarify the function of this vitamin in the parasite

Ribosome slowed by mutation to streptomycin resistance. [Escherichia coli

Energy Technology Data Exchange (ETDEWEB)

Galas, D J; Branscomb, E W

1976-08-12

The effect of mutation to streptomycin resistance on the speed of polypeptide elongation in Escherichia coli was investigated. Translation speed was determined by measuring the time required for the first newly synthesized ..beta..-galactosidase molecules to appear after induction of the lactose operon. The results showed that ribosome speed is not a fixed parameter inherent to the protein synthetic apparatus, but a variable determined by the kinetics of translation and ultimately by the structure of the ribosome. (HLW)

Increased therapeutic efficacy of a newly synthesized tyrosinase inhibitor by solid lipid nanoparticles in the topical treatment of hyperpigmentation

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Al-Amin M

2016-12-01

Full Text Available Md Al-Amin, Jiafu Cao, Muhammad Naeem, Hasanul Banna, Min-Soo Kim, Yunjin Jung, Hae Young Chung, Hyung Ryong Moon, Jin-Wook Yoo College of Pharmacy, Pusan National University, Busan, South Korea Abstract: Hyperpigmentation caused by melanin overproduction is a major skin disorder in humans. Inhibition of tyrosinase, a key regulator of melanin production, has been used as an effective strategy to treat hyperpigmentation. In this study, we investigated the use of solid lipid nanoparticles (SLNs as a highly effective and nontoxic means to deliver a newly synthesized potent tyrosinase inhibitor, MHY498, and to target melanocytes through the skin. MHY498-loaded SLNs (MHY-SLNs were prepared by an oil-in-water emulsion solvent-evaporation method, and their morphological and physicochemical properties were characterized. MHY-SLNs showed a prolonged drug-release profile and higher skin permeation than that of MHY solution. In an in vivo evaluation of antimelanogenic activity, MHY-SLNs showed a prominent inhibitory effect against ultraviolet B-induced melanogenesis, resulting in no change in the skin color of C57BL/6 mouse, compared with that observed in an MHY solution-treated group and an untreated control group. The antimelanogenic effect of MHY-SLNs was further confirmed through Fontana–Masson staining. Importantly, MHY-SLNs did not induce any toxic effects in the L929 cell line. Overall, these data indicate that MHY-SLNs show promise in the topical treatment of hyperpigmentation. Keywords: melanogenesis, hyperpigmentation, MHY498, solid lipid nanoparticles, skin delivery

Comparison between the polypeptide profile of halophilic bacteria and salt tolerant plants.

Science.gov (United States)

Muñoz, G; González, C; Flores, P; Prado, B; Campos, V

1997-12-01

Changes in the polypeptide profile induced by salt stress in halotolerant and halophilic bacteria, isolated from the Atacama desert (northern Chile), were compared with those in the cotyledons of Prosopis chilensis (Leguminoseae) seedlings, a salt tolerant plant. SDS-PAGE analyses show the presence of four predominant polypeptides, with molecular weights around 78, 70, 60 and 44 kDa respectively, both in bacteria and in cotyledons from P. chilensis seedlings raised under salt stress conditions. Moreover, the 60 and 44 kDa polypeptides seem to be salt responsive, since their concentration increases with increasing NaCl in the growth medium. Our results suggest a common mechanism for salt tolerance in prokaryotes and in eukaryotes.

The mining of toxin-like polypeptides from EST database by single residue distribution analysis.

Science.gov (United States)

Kozlov, Sergey; Grishin, Eugene

2011-01-31

Novel high throughput sequencing technologies require permanent development of bioinformatics data processing methods. Among them, rapid and reliable identification of encoded proteins plays a pivotal role. To search for particular protein families, the amino acid sequence motifs suitable for selective screening of nucleotide sequence databases may be used. In this work, we suggest a novel method for simplified representation of protein amino acid sequences named Single Residue Distribution Analysis, which is applicable both for homology search and database screening. Using the procedure developed, a search for amino acid sequence motifs in sea anemone polypeptides was performed, and 14 different motifs with broad and low specificity were discriminated. The adequacy of motifs for mining toxin-like sequences was confirmed by their ability to identify 100% toxin-like anemone polypeptides in the reference polypeptide database. The employment of novel motifs for the search of polypeptide toxins in Anemonia viridis EST dataset allowed us to identify 89 putative toxin precursors. The translated and modified ESTs were scanned using a special algorithm. In addition to direct comparison with the motifs developed, the putative signal peptides were predicted and homology with known structures was examined. The suggested method may be used to retrieve structures of interest from the EST databases using simple amino acid sequence motifs as templates. The efficiency of the procedure for directed search of polypeptides is higher than that of most currently used methods. Analysis of 39939 ESTs of sea anemone Anemonia viridis resulted in identification of five protein precursors of earlier described toxins, discovery of 43 novel polypeptide toxins, and prediction of 39 putative polypeptide toxin sequences. In addition, two precursors of novel peptides presumably displaying neuronal function were disclosed.

Processes for the production of hydroxycinnamic acids using polypeptides having tyrosine ammonia lyase activity

DEFF Research Database (Denmark)

2016-01-01

The present invention generally relates to the field of biotechnology as it applies to the production of hydroxycinnamic acids using polypeptides having tyrosine ammonia lyase activity. More particularly, the present invention pertains to polypeptides having tyrosine ammonia lyase activity and high...... substrate specificity towards tyrosine, which makes them particularly suitable in the production of p-coumaric acid and other hydroxycinnamic acids. The present invention thus provides processes for the production of p-coumaric acid and other hydroxycinnamic acids employing these polypeptides as well...

Fabrication of genetically engineered polypeptide@quantum dots hybrid nanogels for targeted imaging

Science.gov (United States)

Yang, Jie; Yao, Ming-Hao; Zhao, Dong-Hui; Zhang, Xiao-Shuai; Jin, Rui-Mei; Zhao, Yuan-Di; Liu, Bo

2017-08-01

Nanogels have been widely used as multifunctional drug delivery carriers because of high water content, biocompatibility, and high loading capability. We designed and biosynthesized two triblock artificial polypeptides PC10A and PC10ARGD as vehicles for encapsulating hydrophobic materials. These polypeptides can form nanogels by self-assembly when the concentration is below 2% ( w/ v). The physical properties of nanogels, including size, surface potential, and targeting domain, are able to be tuned. Hydrophobic materials from molecular size to nano-size can be loaded into the polypeptide nanogels to form hybrid nanogels. Hydrophobic quantum dots CdSe@ZnS below 10 nM were loaded into the polypeptide nanogels by ultrasonic treatment. Encapsulation endows hydrophobic QDs with good tunability of size, water solubility, stability, targeting, and biocompatibility. PC10ARGD nanogels and PC10ARGD@QDs hybrid nanogels showed excellent biocompatibility, which the cellular viabilities of HeLa and MCF-7 cells treated with 1% PC10ARGD nanogels and PC10ARGD@QDs hybrid nanogels contained 20 nM QDs were above 90 and 80%, respectively. PC10ARGD@QDs hybrid nanogels with an arginine-glycine-aspartic acid motif present efficient receptor-mediated endocytosis in α v β 3 overexpressing HeLa cells but not in the control MCF-7 cells as analyzed by confocal microscopy. These results demonstrate that such polypeptide nanogels as nanocarriers are expected to have great potential applications in biomedicine.

Structural variation and inhibitor binding in polypeptide deformylase from four different bacterial species.

Science.gov (United States)

Smith, Kathrine J; Petit, Chantal M; Aubart, Kelly; Smyth, Martin; McManus, Edward; Jones, Jo; Fosberry, Andrew; Lewis, Ceri; Lonetto, Michael; Christensen, Siegfried B

2003-02-01

Polypeptide deformylase (PDF) catalyzes the deformylation of polypeptide chains in bacteria. It is essential for bacterial cell viability and is a potential antibacterial drug target. Here, we report the crystal structures of polypeptide deformylase from four different species of bacteria: Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae, and Escherichia coli. Comparison of these four structures reveals significant overall differences between the two Gram-negative species (E. coli and H. influenzae) and the two Gram-positive species (S. pneumoniae and S. aureus). Despite these differences and low overall sequence identity, the S1' pocket of PDF is well conserved among the four enzymes studied. We also describe the binding of nonpeptidic inhibitor molecules SB-485345, SB-543668, and SB-505684 to both S. pneumoniae and E. coli PDF. Comparison of these structures shows similar binding interactions with both Gram-negative and Gram-positive species. Understanding the similarities and subtle differences in active site structure between species will help to design broad-spectrum polypeptide deformylase inhibitor molecules.

The mining of toxin-like polypeptides from EST database by single residue distribution analysis

Directory of Open Access Journals (Sweden)

Grishin Eugene

2011-01-01

Full Text Available Abstract Background Novel high throughput sequencing technologies require permanent development of bioinformatics data processing methods. Among them, rapid and reliable identification of encoded proteins plays a pivotal role. To search for particular protein families, the amino acid sequence motifs suitable for selective screening of nucleotide sequence databases may be used. In this work, we suggest a novel method for simplified representation of protein amino acid sequences named Single Residue Distribution Analysis, which is applicable both for homology search and database screening. Results Using the procedure developed, a search for amino acid sequence motifs in sea anemone polypeptides was performed, and 14 different motifs with broad and low specificity were discriminated. The adequacy of motifs for mining toxin-like sequences was confirmed by their ability to identify 100% toxin-like anemone polypeptides in the reference polypeptide database. The employment of novel motifs for the search of polypeptide toxins in Anemonia viridis EST dataset allowed us to identify 89 putative toxin precursors. The translated and modified ESTs were scanned using a special algorithm. In addition to direct comparison with the motifs developed, the putative signal peptides were predicted and homology with known structures was examined. Conclusions The suggested method may be used to retrieve structures of interest from the EST databases using simple amino acid sequence motifs as templates. The efficiency of the procedure for directed search of polypeptides is higher than that of most currently used methods. Analysis of 39939 ESTs of sea anemone Anemonia viridis resulted in identification of five protein precursors of earlier described toxins, discovery of 43 novel polypeptide toxins, and prediction of 39 putative polypeptide toxin sequences. In addition, two precursors of novel peptides presumably displaying neuronal function were disclosed.

Biosynthesis and characterization of typical fibroin crystalline polypeptides of silkworm Bombyx mori

Energy Technology Data Exchange (ETDEWEB)

Wang Jiannan, E-mail: wangjn@suda.edu.cn [College of Material Engineering, Soochow University, Suzhou 215021 (China); Yan Shuqin [College of Material Engineering, Soochow University, Suzhou 215021 (China); Lu Changde [Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Bai Lun [College of Material Engineering, Soochow University, Suzhou 215021 (China)

2009-05-05

We aimed to investigate the self-organization/self-assembly mechanisms of silkworm fibroin-based material. In the present study, for the first time, we designed and multimerized four DNA 'monomer' sequences from structurally simple fibroin crystalline peptides or analog, [GAGAGX] (X = A, S, Y and V) to encode polypeptides [GAGAGX]{sub 16} (eGA, eGS, eGY and eGV) using a 'head-to-tail' construction strategy. Multimers were cloned into pGEX-KG and fusion proteins GST-[GAGAGX]{sub 16} (KGA, KGS, KGY and KGV) were efficiently expressed in Escherichia coli. These fusion proteins were isolated and purified by GST affinity chromatography and confirmed by SDS-PAGE and Western blot analysis using antibody reactive to GST. The polypeptides were cleavaged from GST fusion proteins by digesting with thrombin enzyme. The composition of the four polypeptides was confirmed by composition analysis of amino acids, and their abilities to form {beta}-sheet structure were determined by ThT fluorescence spectral analysis. The content of {beta}-sheet among the four polypeptides followed the order: eGS > eGV > eGY > eGA.

Brachytherapy Using Elastin-Like Polypeptides with (131)I Inhibit Tumor Growth in Rabbits with VX2 Liver Tumor.

Science.gov (United States)

Liu, Xinpei; Shen, Yiming; Zhang, Xuqian; Lin, Rui; Jia, Qiang; Chang, Yixiang; Liu, Wenge; Liu, Wentian

2016-10-01

Brachytherapy is a targeted type of radiotherapy utilized in the treatment of cancers. Elastin-like polypeptides are a unique class of genetically engineered peptide polymers that have several attractive properties for brachytherapy. To explore the feasibility and application of brachytherapy for VX2 liver tumor using elastin-like polypeptides with (131)I so as to provide reliable experimental evidence for a new promising treatment of liver cancer. Elastin-like polypeptide as carrier was labeled with (131)I using the iodogen method. Ten eligible rabbits with VX2 liver tumor were randomly divided into the treatment group (n = 5) and control group (n = 5). The treatment group received brachytherapy using elastin-like polypeptide with (131)I, and in the control group, elastin-like polypeptide was injected into the VX2 liver tumor as a control. Periodic biochemical and imaging surveillances were required to assess treatment efficacy. The stability of elastin-like polypeptide with (131)I in vitro was maintained at over 96.8 % for 96 h. Biochemistry and imaging indicated brachytherapy using elastin-like polypeptide with (131)I for liver tumor can improve liver function and inhibit tumor growth (P Elastin-like polypeptide can be an ideal carrier of (131)I and have high labeling efficiency, radiochemical purity and stability. Brachytherapy using elastin-like polypeptide with (131)I for liver tumor is a useful therapy that possesses high antitumor efficacy advantages.

Moisture absorption and retention properties, and activity in alleviating skin photodamage of collagen polypeptide from marine fish skin.

Science.gov (United States)

Hou, Hu; Li, Bafang; Zhang, Zhaohui; Xue, Changhu; Yu, Guangli; Wang, Jingfeng; Bao, Yuming; Bu, Lin; Sun, Jiang; Peng, Zhe; Su, Shiwei

2012-12-01

Collagen polypeptides were prepared from cod skin. Moisture absorption and retention properties of collagen polypeptides were determined at different relative humidities. In addition, the protective effects of collagen polypeptide against UV-induced damage to mouse skin were evaluated. Collagen polypeptides had good moisture absorption and retention properties and could alleviate the damage induced by UV radiation. The action mechanisms of collagen polypeptide mainly involved enhancing immunity, reducing the loss of moisture and lipid, promoting anti-oxidative properties, inhibiting the increase of glycosaminoglycans, repairing the endogenous collagen and elastin protein fibres, and maintaining the ratio of type III to type I collagen. Copyright © 2012 Elsevier Ltd. All rights reserved.

Molecular Docking and Anticonvulsant Activity of Newly Synthesized Quinazoline Derivatives

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Hatem A. Abuelizz

2017-06-01

Full Text Available A new series of quinazoline-4(3H-ones are evaluated for anticonvulsant activity. After intraperitoneal (ip injection to albino mice at a dose of 100 mg/kg body weight, synthesized quinazolin-4(3H-ones (1–24 were examined in the maximal electroshock (MES induced seizures and subcutaneous pentylenetetrazole (scPTZ induced seizure models in mice. The Rotarod method was applied to determine the neurotoxicity. Most of the compounds displayed anticonvulsant activity in the scPTZ screen at a dose range of 0.204–0.376 mmol/mL. Out of twenty-four, compounds 8, 13 and 19 proved to be the most active with a remarkable protection (100% against PTZ induced convulsions and four times more potent activity than ethosuximide. The structure-activity relationship concluded valuable pharmacophoric information, which was confirmed by the molecular docking studies using the target enzyme human carbon anhydrase II (HCA II. The studied quinazoline analogues suggested that the butyl substitution at position 3 has a significant effect on preventing the spread of seizure discharge and on raising the seizure threshold. However, benzyl substitution at position 3 has shown a strong anticonvulsant activity but with less seizure prevention compared to the butyl substitution.

Polycondensation of Asparagine-comprising Dipeptides in Aqueous Media-A Simulation of Polypeptide Formation in Primordial Earth Hydrosphere

Science.gov (United States)

Munegumi, Toratane; Tanikawa, Naoya

2017-09-01

Asparagine and aspartic acid might have mutually transformed in the primordial hydrosphere of the earth, if ammonia and aspartic acid had existed in equilibrium. These amino acids seem to contribute to polypeptides, while the simple amino acids glycine and alanine easily form cyclic dipeptides and do not achieve long peptide chains. Asparagine-comprising dipeptides contribute some kinds of activation forms of dipeptides because these can polymerize faster than asparagine only. The new finding of polypeptide formation suggests a pathway of sequential polypeptides to evolve a diversity of polypeptides.

Polycondensation of Asparagine-comprising Dipeptides in Aqueous Media-A Simulation of Polypeptide Formation in Primordial Earth Hydrosphere.

Science.gov (United States)

Munegumi, Toratane; Tanikawa, Naoya

2017-09-01

Asparagine and aspartic acid might have mutually transformed in the primordial hydrosphere of the earth, if ammonia and aspartic acid had existed in equilibrium. These amino acids seem to contribute to polypeptides, while the simple amino acids glycine and alanine easily form cyclic dipeptides and do not achieve long peptide chains. Asparagine-comprising dipeptides contribute some kinds of activation forms of dipeptides because these can polymerize faster than asparagine only. The new finding of polypeptide formation suggests a pathway of sequential polypeptides to evolve a diversity of polypeptides.

Congenital deficiency of two polypeptide subunits of the iron-protein fragment of mitochondrial complex I.

Science.gov (United States)

Moreadith, R W; Cleeter, M W; Ragan, C I; Batshaw, M L; Lehninger, A L

1987-02-01

Recently, we described a patient with severe lactic acidosis due to congenital complex I (NADH-ubiquinone oxidoreductase) deficiency. We now report further enzymatic and immunological characterizations. Both NADH and ferricyanide titrations of complex I activity (measured as NADH-ferricyanide reductase) were distinctly altered in the mitochondria from the patient's tissues. In addition, antisera against complex I immunoprecipitated NADH-ferricyanide reductase from the control but not the patient's mitochondria. However, immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of complex I polypeptides demonstrated that the majority of the 25 polypeptides comprising complex I were present in the affected mitochondria. A more detailed analysis using subunit selective antisera against the main polypeptides of the iron-protein fragments of complex I revealed a selective absence of the 75- and 13-kD polypeptides. These findings suggest that the underlying basis for this patient's disease was a congenital deficiency of at least two polypeptides comprising the iron-protein fragment of complex I, which resulted in the inability to correctly assemble a functional enzyme complex.

Application of Statistical Thermodynamics To Predict the Adsorption Properties of Polypeptides in Reversed-Phase HPLC.

Science.gov (United States)

Tarasova, Irina A; Goloborodko, Anton A; Perlova, Tatyana Y; Pridatchenko, Marina L; Gorshkov, Alexander V; Evreinov, Victor V; Ivanov, Alexander R; Gorshkov, Mikhail V

2015-07-07

The theory of critical chromatography for biomacromolecules (BioLCCC) describes polypeptide retention in reversed-phase HPLC using the basic principles of statistical thermodynamics. However, whether this theory correctly depicts a variety of empirical observations and laws introduced for peptide chromatography over the last decades remains to be determined. In this study, by comparing theoretical results with experimental data, we demonstrate that the BioLCCC: (1) fits the empirical dependence of the polypeptide retention on the amino acid sequence length with R(2) > 0.99 and allows in silico determination of the linear regression coefficients of the log-length correction in the additive model for arbitrary sequences and lengths and (2) predicts the distribution coefficients of polypeptides with an accuracy from 0.98 to 0.99 R(2). The latter enables direct calculation of the retention factors for given solvent compositions and modeling of the migration dynamics of polypeptides separated under isocratic or gradient conditions. The obtained results demonstrate that the suggested theory correctly relates the main aspects of polypeptide separation in reversed-phase HPLC.

Generation of polypeptide-templated gold nanoparticles using ionizing radiation.

Science.gov (United States)

Walker, Candace Rae; Pushpavanam, Karthik; Nair, Divya Geetha; Potta, Thrimoorthy; Sutiyoso, Caesario; Kodibagkar, Vikram D; Sapareto, Stephen; Chang, John; Rege, Kaushal

2013-08-13

Ionizing radiation, including γ rays and X-rays, are high-energy electromagnetic radiation with diverse applications in nuclear energy, astrophysics, and medicine. In this work, we describe the use of ionizing radiation and cysteine-containing elastin-like polypeptides (C(n)ELPs, where n = 2 or 12 cysteines in the polypeptide sequence) for the generation of gold nanoparticles. In the presence of C(n)ELPs, ionizing radiation doses higher than 175 Gy resulted in the formation of maroon-colored gold nanoparticle dispersions, with maximal absorbance at 520 nm, from colorless metal salts. Visible color changes were not observed in any of the control systems, indicating that ionizing radiation, gold salt solution, and C(n)ELPs were all required for nanoparticle formation. The hydrodynamic diameters of nanoparticles, determined using dynamic light scattering, were in the range of 80-150 nm, while TEM imaging indicated the formation of gold cores 10-20 nm in diameter. Interestingly, C2ELPs formed 1-2 nm diameter gold nanoparticles in the absence of radiation. Our results describe a facile method of nanoparticle formation in which nanoparticle size can be tailored based on radiation dose and C(n)ELP type. Further improvements in these polypeptide-based systems can lead to colorimetric detection of ionizing radiation in a variety of applications.

Synthetic profiles of polypeptides of human oocytes and normal and abnormal preimplantation embryos.

Science.gov (United States)

Capmany, G; Bolton, V N

1999-09-01

There is considerable variation in the rate of development in vitro of individual preimplantation human embryos. The relationship between the rate of development and patterns of polypeptide synthesis in individual embryos was examined using SDS-PAGE and autoradiography. After incubation in [35S]methionine, 19 polypeptide bands were identified that change between fertilization and the morula stage. Although changes in two of the bands occurred in embryos that were developing normally and in ageing oocytes, and are thus independent of fertilization, the changes identified in the remaining 17 bands occurred only after fertilization. In embryos that were developing abnormally, as assessed by delayed cleavage, cleavage arrest or extensive fragmentation, the alteration in polypeptide synthetic profiles increased with increasing abnormality.

Characterization of an amidated form of pancreatic polypeptide from the daddy sculpin (Cottus scorpius).

Science.gov (United States)

Conlon, J M; Schmidt, W E; Gallwitz, B; Falkmer, S; Thim, L

1986-12-30

The primary structure of pancreatic polypeptide from the teleostean fish, Cottus scorpius (daddy sculpin) was established as: YPPQPESPGGNASPEDWAKYHAAVRHYVNLITRQRYNH2 The presence of a COOH-terminally alpha-amidated amino acid was established using an HPLC method of general applicability. Although the peptide shows strong homology towards anglerfish pancreatic polypeptide (86%), homology towards porcine peptide YY (PYY) (61%) and porcine neuropeptide Y (NPY) (61%) was greater than towards porcine pancreatic polypeptide (PP) (47%). This result supports suggestions that the gene duplication events which led to PP, NPY and PYY formation took place after the time of divergence of fish and mammals.

Molecular diversity and hypoglycemic polypeptide-P content of Momordica charantia in different accessions and different seasons.

Science.gov (United States)

Tian, Miao; Zeng, Xiang-Qing; Song, Huan-Lei; Hu, Shan-Xin; Wang, Fu-Jun; Zhao, Jian; Hu, Zhi-Bi

2015-04-01

Momordica charantia (MC) has been used for treating diabetes mellitus from ancient times in Asia, Africa and South America. There are many MC accessions in local markets. Polypeptide-P as a main hypoglycemic component in MC was first studied in this experiment to illustrate the different contents in MC of different accessions and different harvesting times. Nineteen MC accessions collected from different regions were clustered into three groups using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) molecular markers. Content of polypeptide-P in the tested MC accessions was detected by western blot (WB) method. The WB results revealed that polypeptide-P was detected in MC accessions harvested in June and July but not in September and October. Furthermore, Polypeptide-P content corresponded well with the MC accessions. Our results suggest that the MC accessions and the harvesting times or the weather during harvest play significant roles in high content of polypeptide-P. © 2014 Society of Chemical Industry.

Peptides and polypeptides as scaffolds for optoelectronics and biomaterials applications

Science.gov (United States)

Charati, Manoj B.

designed a multi-component elastomeric polypeptide scaffold containing a resilin mimetic flexible domain that governs the mechanical properties, a cell adhesion domain, a proteolytic degradation site and a growth factor binding domain for applications in tissue regeneration. The modular protein was synthesized in an E. coli host and the purified protein, as analyzed via CD and FTIR exhibited mainly unordered conformation with slight contribution from type II beta-turns. The crosslinked protein is highly elastic in nature and support cell attachment. There materials could be used for tissue repair where high frequency responsiveness and superior fatigue resistance are important, such as scaffolds for vocal fold regenerations and as cardiovascular patches.

Cotranslational structure acquisition of nascent polypeptides monitored by NMR spectroscopy.

Science.gov (United States)

Eichmann, Cédric; Preissler, Steffen; Riek, Roland; Deuerling, Elke

2010-05-18

The folding of proteins in living cells may start during their synthesis when the polypeptides emerge gradually at the ribosomal exit tunnel. However, our current understanding of cotranslational folding processes at the atomic level is limited. We employed NMR spectroscopy to monitor the conformation of the SH3 domain from alpha-spectrin at sequential stages of elongation via in vivo ribosome-arrested (15)N,(13)C-labeled nascent polypeptides. These nascent chains exposed either the entire SH3 domain or C-terminally truncated segments thereof, thus providing snapshots of the translation process. We show that nascent SH3 polypeptides remain unstructured during elongation but fold into a compact, native-like beta-sheet assembly when the entire sequence information is available. Moreover, the ribosome neither imposes major conformational constraints nor significantly interacts with exposed unfolded nascent SH3 domain moieties. Our data provide evidence for a domainwise folding of the SH3 domain on ribosomes without significant population of folding intermediates. The domain follows a thermodynamically favorable pathway in which sequential folding units are stabilized, thus avoiding kinetic traps during the process of cotranslational folding.

Practical multipeptide synthesis: dedicated software for the definition of multiple, overlapping peptides covering polypeptide sequences.

Science.gov (United States)

Heegaard, P M; Holm, A; Hagerup, M

1993-01-01

A personal computer program for the conversion of linear amino acid sequences to multiple, small, overlapping peptide sequences has been developed. Peptide lengths and "jumps" (the distance between two consecutive overlapping peptides) are defined by the user. To facilitate the use of the program for parallel solid-phase chemical peptide syntheses for the synchronous production of multiple peptides, amino acids at each acylation step are laid out by the program in a convenient standard multi-well setup. Also, the total number of equivalents, as well as the derived amount in milligrams (depend-ending on user-defined equivalent weights and molar surplus), of each amino acid are given. The program facilitates the implementation of multipeptide synthesis, e.g., for the elucidation of polypeptide structure-function relationships, and greatly reduces the risk of introducing mistakes at the planning step. It is written in Pascal and runs on any DOS-based personal computer. No special graphic display is needed.

The 75-kilodalton cytoplasmic Chlamydia trachomatis L2 polypeptide is a DnaK-like protein

DEFF Research Database (Denmark)

Birkelund, Svend; Lundemose, AG; Christiansen, Gunna

1990-01-01

,980-base-pair open reading frame revealed 94% homology with a 75-kilodalton protein from C. trachomatis serovar D and 57% homology with the DnaK proteins of E. coli and of Bacillus megaterium, while amino acid homology with human heat shock protein 70 (hsp70) was 42%. The promoter region was identified......The gene coding for the 75-kilodalton cytoplasmic Chlamydia trachomatis L2 polypeptide has been cloned in Escherichia coli, and the nucleotide sequence has been determined. The cloned DNA fragment contained the coding region as well as the putative promoter. The deduced amino acid sequence of the 1...... by computer search and by primer extension of mRNA synthesized in recombinant E. coli. The promoter region which differed from the putative promoter region in serovar D was shown to be a mixed promoter type in which the -10 region showed a regular TATA box configuration while the -35 region showed high...

Nanostructured complexes of polyelectrolytes and charged polypeptides

Czech Academy of Sciences Publication Activity Database

Müller, M.; Ouyang, W.; Bohatá, Karolína; Kessler, B.

2010-01-01

Roč. 12, Sp. Iss. 9 (2010), B519-B528 ISSN 1438-1656. [Sino-German Symposium on Advanced Biomedical Nanostructures /1./. Jena, 26.10.2009-30.10.2009] Institutional research plan: CEZ:AV0Z40500505 Keywords : situ ATR-FTIR * alpha-helical polypeptides * multilayer films Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.746, year: 2010

GAWK, a novel human pituitary polypeptide: isolation, immunocytochemical localization and complete amino acid sequence.

Science.gov (United States)

Benjannet, S; Leduc, R; Lazure, C; Seidah, N G; Marcinkiewicz, M; Chrétien, M

1985-01-16

During the course of reverse-phase high pressure liquid chromatography (RP-HPLC) purification of a postulated big ACTH (1) from human pituitary gland extracts, a highly purified peptide bearing no resemblance to any known polypeptide was isolated. The complete sequence of this 74 amino acid polypeptide, called GAWK, has been determined. Search on a computer data bank on the possible homology to any known protein or fragment, using a mutation data matrix, failed to reveal any homology greater than 30%. An antibody produced against a synthetic fragment allowed us to detect several immunoreactive forms. The antisera also enabled us to localize the polypeptide, by immunocytochemistry, in the anterior lobe of the pituitary gland.

Biosynthesis and characterization of a non-repetitive polypeptide derived from silk fibroin heavy chain

Energy Technology Data Exchange (ETDEWEB)

Yang, Gaoqiang; Wu, Mingyang; Yi, Honggen; Wang, Jiannan, E-mail: wangjn@suda.edu.cn

2016-02-01

Silk fibroin heavy chain is the major protein component of Bombyx mori silk fibroin and is composed of 12 repetitive and 11 non-repetitive regions, with the non-repetitive domain consisting of a hydrophilic polypeptide chain. In order to determine the biomedical function of the non-repetitive domain or potentially use it to modify hydrophobic biomaterials, high-purity isolation is necessary. Previously, we cloned and extended a gene motif (f(1)) encoding the non-repetitive domain. Here, this motif and its multimers are inserted into a glutathione S-transferase (GST)-tagged fusion-protein expression vector. Motif f(1) and multimers f(4) and f(8) were expressed in Escherichia coli BL21 cells following isopropyl β-D-1-thiogalactopyranoside induction, purified by GST-affinity chromatography, and single bands of purified fusion proteins GST-F(1), GST-F(4), and GST-F(8), were visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Target polypeptides F(1), F(4), and F(8), were cleaved clearly from the GST-fusion tag following thrombin digestion. Mass spectrometry results indicate that the molecular weights associated with fusion proteins GST-F(1), GST-F(4), and GST-F(8) are 31.5, 43.8, and 59.0 kDa, respectively, and with the cleaved polypeptides F(1), F(4), and F(8) are 4.8, 16.8, and 32.8 kDa, respectively. The F(1), F(4), and F(8) polypeptide chains are negatively charged with isoelectric points (pI) of 3.3, 3.2, and 3.0, respectively. The molecular weight and pI values of the polypeptide chains are consistent with the predicted values and the amino acid compositions similar to predicted sequences. FTIR and CD results show the molecular conformation of F(1) was mainly random coil, and more stable α-helix structure formed in longer molecular chain. - Highlights: • A non-repetitive domain and its multimers of silk fibroin were expressed by E. coli. • The corresponding target polypeptides F(1), F(4) and F(8) were cleaved clearly. • Their

Investigation of the pathophysiological mechanisms of migraine attacks induced by pituitary adenylate cyclase-activating polypeptide-38

DEFF Research Database (Denmark)

Amin, Faisal Mohammad; Hougaard, Anders; Schytz, Henrik W

2014-01-01

Pituitary adenylate cyclase-activating polypeptide-38 (PACAP38) and vasoactive intestinal polypeptide are structurally and functionally closely related but show differences in migraine-inducing properties. Mechanisms responsible for the difference in migraine induction are unknown. Here, for the ...

The Generation of Dehydroalanine Residues in Protonated Polypeptides: Ion/Ion Reactions for Introducing Selective Cleavages

Science.gov (United States)

Peng, Zhou; Bu, Jiexun; McLuckey, Scott A.

2017-09-01

We examine a gas-phase approach for converting a subset of amino acid residues in polypeptide cations to dehydroalanine (Dha). Subsequent activation of the modified polypeptide ions gives rise to specific cleavage N-terminal to the Dha residue. This process allows for the incorporation of selective cleavages in the structural characterization of polypeptide ions. An ion/ion reaction within the mass spectrometer between a multiply protonated polypeptide and the sulfate radical anion introduces a radical site into the multiply protonated polypeptide reactant. Subsequent collisional activation of the polypeptide radical cation gives rise to radical side chain loss from one of several particular amino acid side chains (e.g., leucine, asparagine, lysine, glutamine, and glutamic acid) to yield a Dha residue. The Dha residues facilitate preferential backbone cleavages to produce signature c- and z-ions, demonstrated with cations derived from melittin, mechano growth factor (MGF), and ubiquitin. The efficiencies for radical side chain loss and for subsequent generation of specific c- and z-ions have been examined as functions of precursor ion charge state and activation conditions using cations of ubiquitin as a model for a small protein. It is noted that these efficiencies are not strongly dependent on ion trap collisional activation conditions but are sensitive to precursor ion charge state. Moderate to low charge states show the greatest overall yields for the specific Dha cleavages, whereas small molecule losses (e.g., water/ammonia) dominate at the lowest charge states and proton catalyzed amide bond cleavages that give rise to b- and y-ions tend to dominate at high charge states. [Figure not available: see fulltext.

Pituitary adenylate cyclase activating polypeptide reduces A-type K+ currents and caspase activity in cultured adult mouse olfactory neurons.

Science.gov (United States)

Han, P; Lucero, M T

2005-01-01

Pituitary adenylate cyclase activating polypeptide has been shown to reduce apoptosis in neonatal cerebellar and olfactory receptor neurons, however the underlying mechanisms have not been elucidated. In addition, the neuroprotective effects of pituitary adenylate cyclase activating polypeptide have not been examined in adult tissues. To study the effects of pituitary adenylate cyclase activating polypeptide on neurons in apoptosis, we measured caspase activation in adult olfactory receptor neurons in vitro. Interestingly, we found that the protective effects of pituitary adenylate cyclase activating polypeptide were related to the absence of a 4-aminopyridine (IC50=144 microM) sensitive rapidly inactivating potassium current often referred to as A-type current. In the presence of 40 nM pituitary adenylate cyclase activating polypeptide 38, both A-type current and activated caspases were significantly reduced. A-type current reduction by pituitary adenylate cyclase activating polypeptide was blocked by inhibiting the phospholipase C pathway, but not the adenylyl cyclase pathway. Our observation that 5 mM 4-aminopyridine mimicked the caspase inhibiting effects of pituitary adenylate cyclase activating polypeptide indicates that A-type current is involved in apoptosis. This work contributes to our growing understanding that potassium currents are involved with the activation of caspases to affect the balance between cell life and death.

Mitochondrial nucleoid clusters protect newly synthesized mtDNA during Doxorubicin- and Ethidium Bromide-induced mitochondrial stress

Energy Technology Data Exchange (ETDEWEB)

Alán, Lukáš, E-mail: lukas.alan@fgu.cas.cz; Špaček, Tomáš; Pajuelo Reguera, David; Jabůrek, Martin; Ježek, Petr

2016-07-01

Mitochondrial DNA (mtDNA) is compacted in ribonucleoprotein complexes called nucleoids, which can divide or move within the mitochondrial network. Mitochondrial nucleoids are able to aggregate into clusters upon reaction with intercalators such as the mtDNA depletion agent Ethidium Bromide (EB) or anticancer drug Doxorobicin (DXR). However, the exact mechanism of nucleoid clusters formation remains unknown. Resolving these processes may help to elucidate the mechanisms of DXR-induced cardiotoxicity. Therefore, we addressed the role of two key nucleoid proteins; mitochondrial transcription factor A (TFAM) and mitochondrial single-stranded binding protein (mtSSB); in the formation of mitochondrial nucleoid clusters during the action of intercalators. We found that both intercalators cause numerous aberrations due to perturbing their native status. By blocking mtDNA replication, both agents also prevented mtDNA association with TFAM, consequently causing nucleoid aggregation into large nucleoid clusters enriched with TFAM, co-existing with the normal nucleoid population. In the later stages of intercalation (> 48 h), TFAM levels were reduced to 25%. In contrast, mtSSB was released from mtDNA and freely distributed within the mitochondrial network. Nucleoid clusters mostly contained nucleoids with newly replicated mtDNA, however the nucleoid population which was not in replication mode remained outside the clusters. Moreover, the nucleoid clusters were enriched with p53, an anti-oncogenic gatekeeper. We suggest that mitochondrial nucleoid clustering is a mechanism for protecting nucleoids with newly replicated DNA against intercalators mediating genotoxic stress. These results provide new insight into the common mitochondrial response to mtDNA stress and can be implied also on DXR-induced mitochondrial cytotoxicity. - Highlights: • The mechanism for mitochondrial nucleoid clustering is proposed. • DNA intercalators (Doxorubicin or Ethidium Bromide) prevent TFAM

Molecular cloning and protein structure of a human blood group Rh polypeptide

International Nuclear Information System (INIS)

Cherif-Zahar, B.; Bloy, C.; Le Van Kim, C.; Blanchard, D.; Bailly, P.; Hermand, P.; Salmon, C.; Cartron, J.P.; Colin, Y.

1990-01-01

cDNA clones encoding a human blood group Rh polypeptide were isolated from a human bone marrow cDNA library by using a polymerase chain reaction-amplified DNA fragment encoding the known common N-terminal region of the Rh proteins. The entire primary structure of the Rh polypeptide has been deduced from the nucleotide sequence of a 1384-base-pair-long cDNA clone. Translation of the open reading frame indicates that the Rh protein is composed of 417 amino acids, including the initiator methionine, which is removed in the mature protein, lacks a cleavable N-terminal sequence, and has no consensus site for potential N-glycosylation. The predicted molecular mass of the protein is 45,500, while that estimated for the Rh protein analyzed in NaDodSO 4 /polyacrylamide gels is in the range of 30,000-32,000. These findings suggest either that the hydrophobic Rh protein behaves abnormally on NaDodSO 4 gels or that the Rh mRNA may encode a precursor protein, which is further matured by a proteolytic cleavage of the C-terminal region of the polypeptide. Hydropathy analysis and secondary structure predictions suggest the presence of 13 membrane-spanning domains, indicating that the Rh polypeptide is highly hydrophobic and deeply buried within the phospholipid bilayer. These results suggest that the expression of the Rh gene(s) might be restricted to tissues or cell lines expressing erythroid characters

The fate and role of macromolecules synthesized during mammalian oocyte meiotic maturation. I. Autoradiographic topography of newly synthesized RNA and protein in the germinal vesicle of the pig and rabbit

International Nuclear Information System (INIS)

Motlik, J.; Kopecny, V.; Pivko, J.

1978-01-01

Pig and rabbit oocytes were cytoautoradiographically checked for their synthetic activities during meiotic maturation. Tritiated uridine and lysine or 35 S-methionine were introduced into the culture medium in which the oocytes were maintained either immediately at the beginning of the germinal vesicle breakdown in vitro or after reaching a more advanced stage of this process in vitro or in vivo. Some oocytes were maintained thereafter in a cold medium to trace the metabolism of the labelled protein. In addition to uridine- 3 H incorporation into the nucleolus and nucleoplasm, during pig oocyte maturation it was found that an intensive RNA synthesis site appeared in association with condensing chromocentres of the GV II. A considerable proportion of oocytes from slaughterhouse material did not show intensive GV activity in RNA synthesis during maturation in vitro. In the pig and rabbit oocyte it was shown that the newly synthesized 3 H-lysine-labelled protein accumulated to a high degree in the GV and in the nucleolus. The labelled protein accumulated in the GV up to the stage of GV IV (pig) and persisted during the chase period in the ooplasm; it was found to be associated with chromosomes of metaphase I (pig) or metaphase II (rabbit) of the meiotic division. The process of protein accumulation in the GV was not influenced by meiotic arrest during oocyte culture in autologous follicular fluid. A similar accumulation of the label in the GV was detected in oocytes which were cultured in a medium enriched by 35 S-methionine. In some oocytes the labelled protein failed to accumulate in the nucleolar area during maturation in vitro

Phase transition in polypeptides: a step towards the understanding of protein folding

DEFF Research Database (Denmark)

Yakubovich, Alexander V.; Solov'yov, Ilia; Solov'yov, Andrey V.

2006-01-01

We present a formalism which turns out to be very successful in the description of the polypeptide folding. We consider this process as a first-order phase transition and develop a theory which is free of model parameters and is based solely on fundamental physical principles. It describes...... essential thermodynamical properties of the system such as heat capacity, the phase transition temperature and others from the analysis of the polypeptide potential energy surface calculated within ab initio density functional theory and parameterized by two dihedral angles. This problem is viewed...

Solid-phase extraction of the alcohol abuse biomarker phosphatidylethanol using newly synthesized polymeric sorbent materials containing quaternary heterocyclic groups.

Science.gov (United States)

Duarte, Mariana; Jagadeesan, Kishore Kumar; Billing, Johan; Yilmaz, Ecevit; Laurell, Thomas; Ekström, Simon

2017-10-13

Phosphatidylethanol (PEth) is an interesting biomarker finding increased use for detecting long term alcohol abuse with high specificity and sensitivity. Prior to detection, sample preparation is an unavoidable step in the work-flow of PEth analysis and new protocols may facilitate it. Solid-phase extraction (SPE) is a versatile sample preparation method widely spread in biomedical laboratories due to its simplicity of use and the possibility of automation. In this work, SPE was used for the first time to directly extract PEth from spiked human plasma and spiked human blood. A library of polymeric SPE materials with different surface functionalities was screened for PEth extraction in order to identify the surface characteristics that control PEth retention and recovery. The plasma samples were diluted 1:10 (v/v) in water and spiked at different concentrations ranging from 0.3 to 5μM. The library of SPE materials was then evaluated using the proposed SPE method and detection was done by LC-MS/MS. One SPE material efficiently retained and recovered PEth from spiked human plasma. With this insight, four new SPE materials were formulated and synthesized based on the surface characteristics of the best SPE material found in the first screening. These new materials were tested with spiked human blood, to better mimic a real clinical sample. All the newly synthetized materials outperformed the pre-existing commercially available materials. Recovery values for the new SPE materials were found between 29.5% and 48.6% for the extraction of PEth in spiked blood. A material based on quaternized 1-vinylimidazole with a poly(trimethylolpropane trimethacrylate) backbone was found suitable for PEth extraction in spiked blood showing the highest analyte recovery in this experiment, 48.6%±6.4%. Copyright © 2017 Elsevier B.V. All rights reserved.

Immunoassay of serum polypeptide hormones by using 125I-labelled anti(-immunoglobulin G) antibodies.

Science.gov (United States)

Beck, P; Nicholas, H

1975-03-01

1. A technique for indirectly labelling antibodies to polypeptide hormones, by combining them with radioactively labelled anti-(immunoglobulin G) is described. (a) 125I-labelled anti-(rabbit immunoglobulin G) and anti-(guinea-pig immunoglobulin G) antibodies with high specific radioactivity were prepared after purification of the antibodies on immunoadsorbents containing the respective antigens. (b) Rabbit immunoglobulin G antibodies to human growth hormone, porcine glucagon and guinea-pig immunoglobulin G antibodies to bovine insulin and bovine parathyroid hormone were combined with immunoadsorbents containing the respective polypeptide hormone antigen. (c) The immunoglobulin G antibodies to the polypeptide hormones were reacted with 125-I-labelled anti-(immunoglobulin G) antibodies directed against the appropriate species of immunoglobulin G,and the anti-hormone antibodies were combined with the hormone-containing immunoadsorbent. (d) 125I-labelled anti-(immunoglobulin G) antibodies and anti-hormone antibodies were simultaneously eluted from the hormone-containing immunoadsorbent by dilute HCl, pH 2.0. After elution the anti-(immunoglobulin G) antibodies and antihormone antibodies were allowed to recombine at pH 8.0 and 4 degrees C. 2. The resultant immunoglobulin G-anti-immunoglobulin G complex was used in immunoradiometric (labelled antibody) and two-site assays of the respective polypeptide hormone. 3. By using these immunoassays, concentrations down to 90pg of human growth hormone/ml, 100 pg of bovine insulin/ml, 80 pg of bovine parathyroid hormone/ml and 150 pg of glucagon/ml were readily detected. Assays of human plasma for growth hormone and insulin by these methods showed good agreement with results obtained by using a directly 125I-labelled anti-hormone antibody in an immunoradiometric assay of human growth hormone or by radioimmunoassay of human insulin. 4. The method described allows immunoradiometric or two-site assays to be performed starting with as

Identification and characterization of human polyserase-3, a novel protein with tandem serine-protease domains in the same polypeptide chain

Directory of Open Access Journals (Sweden)

Garabaya Cecilia

2006-03-01

Full Text Available Abstract Background We have previously described the identification and characterization of polyserase-1 and polyserase-2, two human serine proteases containing three different catalytic domains within the same polypeptide chain. Polyserase-1 shows a complex organization and it is synthesized as a membrane-bound protein which can generate three independent serine protease domains as a consequence of post-translational processing events. The two first domains are enzymatically active. By contrast, polyserase-2 is an extracellular glycosylated protein whose three protease domains remain embedded in the same chain, and only the first domain possesses catalytic activity. Results Following our interest in the study of the human degradome, we have cloned a human liver cDNA encoding polyserase-3, a new protease with tandem serine protease domains in the same polypeptide chain. Comparative analysis of polyserase-3 with the two human polyserases described to date, revealed that this novel polyprotein is more closely related to polyserase-2 than to polyserase-1. Thus, polyserase-3 is a secreted protein such as polyserase-2, but lacks additional domains like the type II transmembrane motif and the low-density lipoprotein receptor module present in the membrane-anchored polyserase-1. Moreover, analysis of post-translational mechanisms operating in polyserase-3 maturation showed that its two protease domains remain as integral parts of the same polypeptide chain. This situation is similar to that observed in polyserase-2, but distinct from polyserase-1 whose protease domains are proteolytically released from the original chain to generate independent units. Immunolocalization studies indicated that polyserase-3 is secreted as a non-glycosylated protein, thus being also distinct from polyserase-2, which is a heavily glycosylated protein. Enzymatic assays indicated that recombinant polyserase-3 degrades the α-chain of fibrinogen as well as pro

Sequence Directionality Dramatically Affects LCST Behavior of Elastin-Like Polypeptides.

Science.gov (United States)

Li, Nan K; Roberts, Stefan; Quiroz, Felipe Garcia; Chilkoti, Ashutosh; Yingling, Yaroslava G

2018-04-30

Elastin-like polypeptides (ELP) exhibit an inverse temperature transition or lower critical solution temperature (LCST) transition phase behavior in aqueous solutions. In this paper, the thermal responsive properties of the canonical ELP, poly(VPGVG), and its reverse sequence poly(VGPVG) were investigated by turbidity measurements of the cloud point behavior, circular dichroism (CD) measurements, and all-atom molecular dynamics (MD) simulations to gain a molecular understanding of mechanism that controls hysteretic phase behavior. It was shown experimentally that both poly(VPGVG) and poly(VGPVG) undergo a transition from soluble to insoluble in aqueous solution upon heating above the transition temperature ( T t ). However, poly(VPGVG) resolubilizes upon cooling below its T t , whereas the reverse sequence, poly(VGPVG), remains aggregated despite significant undercooling below the T t . The results from MD simulations indicated that a change in sequence order results in significant differences in the dynamics of the specific residues, especially valines, which lead to extensive changes in the conformations of VPGVG and VGPVG pentamers and, consequently, dissimilar propensities for secondary structure formation and overall structure of polypeptides. These changes affected the relative hydrophilicities of polypeptides above T t , where poly(VGPVG) is more hydrophilic than poly(VPGVG) with more extended conformation and larger surface area, which led to formation of strong interchain hydrogen bonds responsible for stabilization of the aggregated phase and the observed thermal hysteresis for poly(VGPVG).

Chronic changes in pituitary adenylate cyclase-activating polypeptide and related receptors in response to repeated chemical dural stimulation in rats.

Science.gov (United States)

Han, Xun; Ran, Ye; Su, Min; Liu, Yinglu; Tang, Wenjing; Dong, Zhao; Yu, Shengyuan

2017-01-01

Background Preclinical experimental studies revealed an acute alteration of pituitary adenylate cyclase-activating polypeptide in response to a single activation of the trigeminovascular system, which suggests a potential role of pituitary adenylate cyclase-activating polypeptide in the pathogenesis of migraine. However, changes in pituitary adenylate cyclase-activating polypeptide after repeated migraine-like attacks in chronic migraine are not clear. Therefore, the present study investigated chronic changes in pituitary adenylate cyclase-activating polypeptide and related receptors in response to repeated chemical dural stimulations in the rat. Methods A rat model of chronic migraine was established by repeated chemical dural stimulations using an inflammatory soup for a different numbers of days. The pituitary adenylate cyclase-activating polypeptide levels were quantified in plasma, the trigeminal ganglia, and the trigeminal nucleus caudalis using radioimmunoassay and Western blotting in trigeminal ganglia and trigeminal nucleus caudalis tissues. Western blot analysis and real-time polymerase chain reaction were used to measure the protein and mRNA expression of pituitary adenylate cyclase-activating polypeptide-related receptors (PAC1, VPAC1, and VPAC2) in the trigeminal ganglia and trigeminal nucleus caudalis to identify changes associated with repetitive applications of chemical dural stimulations. Results All rats exhibited significantly decreased periorbital nociceptive thresholds to repeated inflammatory soup stimulations. Radioimmunoassay and Western blot analysis demonstrated significantly decreased pituitary adenylate cyclase-activating polypeptide levels in plasma and trigeminal ganglia after repetitive chronic inflammatory soup stimulation. Protein and mRNA analyses of pituitary adenylate cyclase-activating polypeptide-related receptors demonstrated significantly increased PAC1 receptor protein and mRNA expression in the trigeminal ganglia, but not

Adhesive polypeptides of Staphylococcus aureus identified using a novel secretion library technique in Escherichia coli

Directory of Open Access Journals (Sweden)

Holm Liisa

2011-05-01

Full Text Available Abstract Background Bacterial adhesive proteins, called adhesins, are frequently the decisive factor in initiation of a bacterial infection. Characterization of such molecules is crucial for the understanding of bacterial pathogenesis, design of vaccines and development of antibacterial drugs. Because adhesins are frequently difficult to express, their characterization has often been hampered. Alternative expression methods developed for the analysis of adhesins, e.g. surface display techniques, suffer from various drawbacks and reports on high-level extracellular secretion of heterologous proteins in Gram-negative bacteria are scarce. These expression techniques are currently a field of active research. The purpose of the current study was to construct a convenient, new technique for identification of unknown bacterial adhesive polypeptides directly from the growth medium of the Escherichia coli host and to identify novel proteinaceous adhesins of the model organism Staphylococcus aureus. Results Randomly fragmented chromosomal DNA of S. aureus was cloned into a unique restriction site of our expression vector, which facilitates secretion of foreign FLAG-tagged polypeptides into the growth medium of E. coli ΔfliCΔfliD, to generate a library of 1663 clones expressing FLAG-tagged polypeptides. Sequence and bioinformatics analyses showed that in our example, the library covered approximately 32% of the S. aureus proteome. Polypeptides from the growth medium of the library clones were screened for binding to a selection of S. aureus target molecules and adhesive fragments of known staphylococcal adhesins (e.g coagulase and fibronectin-binding protein A as well as polypeptides of novel function (e.g. a universal stress protein and phosphoribosylamino-imidazole carboxylase ATPase subunit were detected. The results were further validated using purified His-tagged recombinant proteins of the corresponding fragments in enzyme-linked immunoassay and

Identification of UDPG-binding polypeptides and purified (1,3)-β-glucan synthase by photoaffinity labelling with 5-azido-UDPG

International Nuclear Information System (INIS)

Frost, D.J.; Wu, A.; Read, S.M.; Wasserman, B.P.; Drake, R.R.; Haley, B.E.

1989-01-01

The photoaffinity probe 5-azido-uridine 5'-β-[ 32 P]-diphosphate glucose was used to identify the major UDPG-binding polypeptide of red beet (1,3)-β-glucan synthase. Glucan synthase was purified from plasma membranes by sequential solubilization with CHAPS followed by product entrapment. Two major polypeptides at 72 and 54 kD were labelled by probe. Labelling of both was abolished with increasing levels of cold UDPG. However, labelling of the 54 kD polypeptide was dependent upon the presence of divalent cations. These data suggest that the 54 kD polypeptide is a substrate-binding and cation-regulated component of the glucan synthase complex

The interdomain flexible linker of the polypeptide GalNAc transferases dictates their long-range glycosylation preferences

DEFF Research Database (Denmark)

Rivas, Matilde De Las; Lira-Navarrete, Erandi; Daniel, Earnest James Paul

2017-01-01

The polypeptide GalNAc-transferases (GalNAc-Ts), that initiate mucin-type O-glycosylation, consist of a catalytic and a lectin domain connected by a flexible linker. In addition to recognizing polypeptide sequence, the GalNAc-Ts exhibit unique long-range N- A nd/or C-terminal prior glycosylation ...

LW-214, a newly synthesized flavonoid, induces intrinsic apoptosis pathway by down-regulating Trx-1 in MCF-7 human breast cells.

Science.gov (United States)

Pan, Di; Li, Wei; Miao, Hanchi; Yao, Jing; Li, Zhiyu; Wei, Libin; Zhao, Li; Guo, Qinglong

2014-02-15

In this study, the anticancer effect of LW-214, a newly synthesized flavonoid, against MCF-7 human breast cancer cells and the underlying mechanisms were investigated. LW-214 triggered the mitochondrial apoptotic pathway by increasing Bax/Bcl-2 ratio, loss of mitochondrial membrane potential (ΔΨm) and caspase-9 activation, degradation of poly (ADP-ribose) polymerase (PARP), cytochrome c (Cyt c) release and apoptosis-inducing factor (AIF) transposition. Further research revealed that both the reactive oxygen species (ROS) generation and the apoptosis signal regulating kinase 1 (ASK1) activation by LW-214 were induced by down-regulating the thioredoxin-1 (Trx-1) expression. The ROS elevation and ASK1 activation induced a sustained phosphorylation of c-Jun N-terminal kinase (JNK), while SP600125, as known as JNK inhibitor, almost reversed LW-214-induced apoptosis in MCF-7 cells. Overexpression of Trx-1 in MCF-7 cells attenuated LW-214-mediated apoptosis as well as the JNK activation and reversed the expression of mitochondrial apoptosis-related protein. Accordingly, the in vivo study showed that LW-214 exhibited a potential antitumor effect in BALB/c species mice inoculated MCF-7 tumor with low systemic toxicity, and the mechanism was the same as in vitro study. Taken together, these findings indicated that LW-214 may down-regulated Trx-1 function, causing intracellular ROS generation and releasing the ASK1, and lead to JNK activation, which consequently induced the mitochondrial apoptosis in vitro and in vivo. Copyright © 2013 Elsevier Inc. All rights reserved.

High-yield recombinant expression and purification of marginally soluble, short elastin-like polypeptides.

Science.gov (United States)

Bahniuk, Markian S; Alshememry, Abdullah K; Unsworth, Larry D

2016-12-01

The protocol described here is designed as an extension of existing techniques for creating elastin-like polypeptides. It allows for the expression and purification of elastin-like polypeptide (ELP) constructs that are poorly expressed or have very low transition temperatures. DNA concatemerization has been modified to reduce issues caused by methylation sensitivity and inefficient cloning. Linearization of the modified expression vector has been altered to greatly increase cleavage efficiency. The purification regimen is based upon using denaturing metal affinity chromatography to fully solubilize and, if necessary, pre-concentrate the target peptide before purification by inverse temperature cycling (ITC). This protocol has been used to express multiple leucine-containing elastin-like polypeptides, with final yields of 250-660 mg per liter of cells, depending on the specific construct. This was considerably greater than previously reported yields for similar ELPs. Due to the relative hydrophobicity of the tested constructs, even compared with commonly employed ELPs, conventional methods would not have been able to be purify these peptides.

Improvement of Learning and Memory Induced by Cordyceps Polypeptide Treatment and the Underlying Mechanism

Directory of Open Access Journals (Sweden)

Guangxin Yuan

2018-01-01

Full Text Available Our previous research revealed that Cordyceps militaris can improve the learning and memory, and although the main active ingredient should be its polypeptide complexes, the underlying mechanism of its activity remains poorly understood. In this study, we explored the mechanisms by which Cordyceps militaris improves learning and memory in a mouse model. Mice were given scopolamine hydrobromide intraperitoneally to establish a mouse model of learning and memory impairment. The effects of Cordyceps polypeptide in this model were tested using the Morris water maze test; serum superoxide dismutase activity; serum malondialdehyde levels; activities of acetyl cholinesterase, Na+-k+-ATPase, and nitric oxide synthase; and gamma aminobutyric acid and glutamate contents in brain tissue. Moreover, differentially expressed genes and the related cellular signaling pathways were screened using an mRNA expression profile chip. The results showed that the genes Pik3r5, Il-1β, and Slc18a2 were involved in the effects of Cordyceps polypeptide on the nervous system of these mice. Our findings suggest that Cordyceps polypeptide may improve learning and memory in the scopolamine-induced mouse model of learning and memory impairment by scavenging oxygen free radicals, preventing oxidative damage, and protecting the nervous system.

Immune-tolerant elastin-like polypeptides (iTEPs) and their application as CTL vaccine carriers.

Science.gov (United States)

Cho, S; Dong, S; Parent, K N; Chen, M

2016-01-01

Cytotoxic T lymphocyte (CTL) vaccine carriers are known to enhance the efficacy of vaccines, but a search for more effective carriers is warranted. Elastin-like polypeptides (ELPs) have been examined for many medical applications but not as CTL vaccine carriers. We aimed to create immune tolerant ELPs using a new polypeptide engineering practice and create CTL vaccine carriers using the ELPs. Four sets of novel ELPs, termed immune-tolerant elastin-like polypeptide (iTEP) were generated according to the principles dictating humoral immunogenicity of polypeptides and phase transition property of ELPs. The iTEPs were non-immunogenic in mice. Their phase transition feature was confirmed through a turbidity assay. An iTEP nanoparticle (NP) was assembled from an amphiphilic iTEP copolymer plus a CTL peptide vaccine, SIINFEKL. The NP facilitated the presentation of the vaccine by dendritic cells (DCs) and enhanced vaccine-induced CTL responses. A new ELP design and development practice was established. The non-canonical motif and the immune tolerant nature of the iTEPs broaden our insights about ELPs. ELPs, for the first time, were successfully used as carriers for CTL vaccines. It is feasible to concurrently engineer both immune-tolerant and functional peptide materials. ELPs are a promising type of CTL vaccine carriers.

Kinetics of Internal-Loop Formation in Polypeptide Chains: A Simulation Study

Science.gov (United States)

Doucet, Dana; Roitberg, Adrian; Hagen, Stephen J.

2007-01-01

The speed of simple diffusional motions, such as the formation of loops in the polypeptide chain, places one physical limit on the speed of protein folding. Many experimental studies have explored the kinetics of formation of end-to-end loops in polypeptide chains; however, protein folding more often requires the formation of contacts between interior points on the chain. One expects that, for loops of fixed contour length, interior loops will form more slowly than end-to-end loops, owing to the additional excluded volume associated with the “tails”. We estimate the magnitude of this effect by generating ensembles of randomly coiled, freely jointed chains, and then using the theory of Szabo, Schulten, and Schulten to calculate the corresponding contact formation rates for these ensembles. Adding just a few residues, to convert an end-to-end loop to an internal loop, sharply decreases the contact rate. Surprisingly, the relative change in rate increases for a longer loop; sufficiently long tails, however, actually reverse the effect and accelerate loop formation slightly. Our results show that excluded volume effects in real, full-length polypeptides may cause the rates of loop formation during folding to depart significantly from the values derived from recent loop-formation experiments on short peptides. PMID:17208979

A Physicochemical and Pharmacological Study of the Newly Synthesized Complex of Albendazole and the Polysaccharide Arabinogalactan from Larch Wood.

Science.gov (United States)

Chistyachenko, Yulia S; Meteleva, Elizaveta S; Pakharukova, Maria Y; Katokhin, Aleksey V; Khvostov, Mikhail V; Varlamova, Anastasiya I; Glamazdin, Igor I; Khalikov, Salavat S; Polyakov, Nikolay E; Arkhipov, Ivan A; Tolstikova, Tatyana G; Mordvinov, Viatcheslav A; Dushkin, Alexander V; Lyakhov, Nikolay Z

2015-01-01

Inclusion complexes of albendazole (ABZ) with the polysaccharide arabinogalactan from larch wood Larix sibirica and Larix gmelinii were synthesized using a solid-state mechanochemical technology. We investigated physicochemical properties of the synthesized complexes in the solid state and in aqueous solutions as well as their anthelmintic activity against Trichinella spiralis, Hymenolepis nаna, Fasciola hepatica, Opisthorchis felineus, and mixed nematodoses of sheep. Formation of the complexes was demonstrated by means of intrinsic solubility and the NMR relaxation method. The mechanochemically synthesized complexes were more stable in comparison with the complex produced by mixing solutions of the components. The complexes of ABZ showed anthelmintic activity at 10-fold lower doses than did free ABZ. The complexes also showed lower acute toxicity and hepatotoxicity. These results suggest that it is possible to design new drugs on the basis of the ABZ:arabinogalactan complex that are safer and more effective than albendazole.

A conserved START domain coenzyme Q-binding polypeptide is required for efficient Q biosynthesis, respiratory electron transport, and antioxidant function in Saccharomyces cerevisiae.

Science.gov (United States)

Allan, Christopher M; Hill, Shauna; Morvaridi, Susan; Saiki, Ryoichi; Johnson, Jarrett S; Liau, Wei-Siang; Hirano, Kathleen; Kawashima, Tadashi; Ji, Ziming; Loo, Joseph A; Shepherd, Jennifer N; Clarke, Catherine F

2013-04-01

Coenzyme Qn (ubiquinone or Qn) is a redox active lipid composed of a fully substituted benzoquinone ring and a polyisoprenoid tail of n isoprene units. Saccharomyces cerevisiae coq1-coq9 mutants have defects in Q biosynthesis, lack Q6, are respiratory defective, and sensitive to stress imposed by polyunsaturated fatty acids. The hallmark phenotype of the Q-less yeast coq mutants is that respiration in isolated mitochondria can be rescued by the addition of Q2, a soluble Q analog. Yeast coq10 mutants share each of these phenotypes, with the surprising exception that they continue to produce Q6. Structure determination of the Caulobacter crescentus Coq10 homolog (CC1736) revealed a steroidogenic acute regulatory protein-related lipid transfer (START) domain, a hydrophobic tunnel known to bind specific lipids in other START domain family members. Here we show that purified CC1736 binds Q2, Q3, Q10, or demethoxy-Q3 in an equimolar ratio, but fails to bind 3-farnesyl-4-hydroxybenzoic acid, a farnesylated analog of an early Q-intermediate. Over-expression of C. crescentus CC1736 or COQ8 restores respiratory electron transport and antioxidant function of Q6 in the yeast coq10 null mutant. Studies with stable isotope ring precursors of Q reveal that early Q-biosynthetic intermediates accumulate in the coq10 mutant and de novo Q-biosynthesis is less efficient than in the wild-type yeast or rescued coq10 mutant. The results suggest that the Coq10 polypeptide:Q (protein:ligand) complex may serve essential functions in facilitating de novo Q biosynthesis and in delivering newly synthesized Q to one or more complexes of the respiratory electron transport chain. Copyright © 2012 Elsevier B.V. All rights reserved.

Newly developed chitosan-silver hybrid nanoparticles: biosafety and apoptosis induction in HepG2 cells

International Nuclear Information System (INIS)

El-Sherbiny, Ibrahim M.; Salih, Ehab; Yassin, Abdelrahman M.; Hafez, Elsayed E.

2016-01-01

The present study reports the biosafety assessment, the exact molecular effects, and apoptosis induction of newly developed chitosan-silver hybrid nanoparticles (Cs–Ag NPs) in HepG2 cells. The investigated hybrid NPs were green synthesized using Cs/grape leaves aqueous extract (Cs/GLE) or Cs/GLE NPs as reducing and stabilizing agents. The successful formation of Cs/GLE NPs and Cs–Ag hybrid NPs has been confirmed by UV–Vis spectrophotometry, FTIR spectroscopy, XRD, and HRTEM. From the TEM analysis, the prepared Cs/GLE NPs are uniform and spherical with an average size of 150 nm, and the AgNPs (5–10 nm) were formed mainly on their surface. The UV–Vis spectra of Cs–Ag NPs showed a surface plasmon resonance (SPR) peak at about 450 nm confirming their formation. The synthesized Cs–Ag NPs were found to be crystalline as shown by XRD patterns with fcc phase oriented along the (111), (200), (220), and (311) planes. The cytotoxicity patterns, the antiproliferative activities, and the possible mechanisms of anticancer activity at molecular level of the newly developed Cs–Ag hybrid NPs were investigated. Cytotoxicity patterns of all the preparations demonstrated that the nontoxic treatment concentrations are ranged from 0.39 to 50 %, and many of the newly prepared Cs–Ag hybrid NPs showed high anticancer activities against HpG2 cells, and induced cellular apoptosis by downregulating BCL2 gene and upregulating P53.Graphical Abstract

Newly developed chitosan-silver hybrid nanoparticles: biosafety and apoptosis induction in HepG2 cells

Energy Technology Data Exchange (ETDEWEB)

El-Sherbiny, Ibrahim M., E-mail: ielsherbiny@Zewailcity.edu.eg; Salih, Ehab [Zewail City of Science and Technology, Center for Materials Science (Egypt); Yassin, Abdelrahman M. [Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technology Applications, Biopharmaceutical Product Research Department (Egypt); Hafez, Elsayed E. [City of Scientific Research and Technology Applications, Plant Protection and Biomolecular Diagnosis Department (Egypt)

2016-07-15

The present study reports the biosafety assessment, the exact molecular effects, and apoptosis induction of newly developed chitosan-silver hybrid nanoparticles (Cs–Ag NPs) in HepG2 cells. The investigated hybrid NPs were green synthesized using Cs/grape leaves aqueous extract (Cs/GLE) or Cs/GLE NPs as reducing and stabilizing agents. The successful formation of Cs/GLE NPs and Cs–Ag hybrid NPs has been confirmed by UV–Vis spectrophotometry, FTIR spectroscopy, XRD, and HRTEM. From the TEM analysis, the prepared Cs/GLE NPs are uniform and spherical with an average size of 150 nm, and the AgNPs (5–10 nm) were formed mainly on their surface. The UV–Vis spectra of Cs–Ag NPs showed a surface plasmon resonance (SPR) peak at about 450 nm confirming their formation. The synthesized Cs–Ag NPs were found to be crystalline as shown by XRD patterns with fcc phase oriented along the (111), (200), (220), and (311) planes. The cytotoxicity patterns, the antiproliferative activities, and the possible mechanisms of anticancer activity at molecular level of the newly developed Cs–Ag hybrid NPs were investigated. Cytotoxicity patterns of all the preparations demonstrated that the nontoxic treatment concentrations are ranged from 0.39 to 50 %, and many of the newly prepared Cs–Ag hybrid NPs showed high anticancer activities against HpG2 cells, and induced cellular apoptosis by downregulating BCL2 gene and upregulating P53.Graphical Abstract.

CDNA encoding a polypeptide including a hevein sequence

Science.gov (United States)

Raikhel, Natasha V.; Broekaert, Willem F.; Chua, Nam-Hai; Kush, Anil

1995-03-21

A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a putative signal sequence of 17 amino acid residues followed by a 187 amino acid polypeptide. The amino-terminal region (43 amino acids) is identical to hevein and shows homology to several chitin-binding proteins and to the amino-termini of wound-induced genes in potato and poplar. The carboxyl-terminal portion of the polypeptide (144 amino acids) is 74-79% homologous to the carboxyl-terminal region of wound-inducible genes of potato. Wounding, as well as application of the plant hormones abscisic acid and ethylene, resulted in accumulation of hevein transcripts in leaves, stems and latex, but not in roots, as shown by using the cDNA as a probe. A fusion protein was produced in E. coli from the protein of the present invention and maltose binding protein produced by the E. coli.

Strategies to Fabricate Polypeptide-Based Structures via Ring-Opening Polymerization of N-Carboxyanhydrides

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Carmen M. González-Henríquez

2017-10-01

Full Text Available In this review, we provide a general and clear overview about the different alternatives reported to fabricate a myriad of polypeptide architectures based on the ring-opening polymerization of N-carbonyanhydrides (ROP NCAs. First of all, the strategies for the preparation of NCA monomers directly from natural occurring or from modified amino acids are analyzed. The synthetic alternatives to prepare non-functionalized and functionalized NCAs are presented. Protection/deprotection protocols, as well as other functionalization chemistries are discussed in this section. Later on, the mechanisms involved in the ROP NCA polymerization, as well as the strategies developed to reduce the eventually occurring side reactions are presented. Finally, a general overview of the synthetic strategies described in the literature to fabricate different polypeptide architectures is provided. This part of the review is organized depending on the complexity of the macromolecular topology prepared. Therefore, linear homopolypeptides, random and block copolypeptides are described first. The next sections include cyclic and branched polymers such as star polypeptides, polymer brushes and highly branched structures including arborescent or dendrigraft structures.

Glucose-dependent Insulinotropic Polypeptide

DEFF Research Database (Denmark)

Christensen, Mikkel B; Calanna, Salvatore; Holst, Jens Juul

2014-01-01

CONTEXT: Patients with type 2 diabetes mellitus (T2DM) have clinically relevant disturbances in the effects of the hormone glucose-dependent insulinotropic polypeptide (GIP). OBJECTIVE: We aimed to evaluate the importance of the prevailing plasma glucose levels for the effect of GIP on responses......: During fasting glycemia (plasma glucose ∼8 mmol/L), GIP elicited significant increments in both insulin and glucagon levels, resulting in neutral effects on plasma glucose. During insulin-induced hypoglycemia (plasma glucose ∼3 mmol/L), GIP elicited a minor early-phase insulin response and increased...... glucagon levels during the initial 30 minutes, resulting in less glucose needed to be infused to maintain the clamp (29 ± 8 vs 49 ± 12 mg × kg(-1), P glucose ∼12 mmol/L), GIP augmented insulin secretion throughout the clamp, with slightly less glucagon...

Investigation of Gelatin Polypeptides of Jellyfish (Rhopilema esculentum for Their Antioxidant Activity in vitro

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Yong-Liang Zhuang

2010-01-01

Full Text Available Jellyfish gelatin was hydrolyzed by different proteases to obtain antioxidative polypeptides. The gelatin hydrolysate obtained by progressive hydrolysis using trypsin and Properase E exhibited the highest hydrolysis degree and antioxidant activity. Three series of gelatin polypeptides (SCP1, SCP2 and SCP3 were obtained by ultrafiltrating the gelatin hydrolysate through molecular mass cut-off membranes of 10, 6 and 2 kDa, respectively. Amino acid composition analysis showed that SCP3 had the highest total hydrophobic amino acid content. The in vitro antioxidant tests demonstrated that SCP2 had the strongest hydroxyl radical and hydrogen peroxide scavenging activities and metal chelating ability, while SCP3 showed the highest reducing power, antioxidant activity in linoleic acid emulsion system and superoxide anion radical scavenging activity. The results support the feasibility of jellyfish gelatin as a natural antioxidant polypeptide provider, and enzymatic hydrolysis and ultrafiltration could be potent future processing technologies to utilize the abundant jellyfish resource.

Evolutionary selection of enzymatically synthesized semiconductors from biomimetic mineralization vesicles.

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Bawazer, Lukmaan A; Izumi, Michi; Kolodin, Dmitriy; Neilson, James R; Schwenzer, Birgit; Morse, Daniel E

2012-06-26

The way nature evolves and sculpts materials using proteins inspires new approaches to materials engineering but is still not completely understood. Here, we present a cell-free synthetic biological platform to advance studies of biologically synthesized solid-state materials. This platform is capable of simultaneously exerting many of the hierarchical levels of control found in natural biomineralization, including genetic, chemical, spatial, structural, and morphological control, while supporting the evolutionary selection of new mineralizing proteins and the corresponding genetically encoded materials that they produce. DNA-directed protein expression and enzymatic mineralization occur on polystyrene microbeads in water-in-oil emulsions, yielding synthetic surrogates of biomineralizing cells that are then screened by flow sorting, with light-scattering signals used to sort the resulting mineralized composites differentially. We demonstrate the utility of this platform by evolutionarily selecting newly identified silicateins, biomineralizing enzymes previously identified from the silica skeleton of a marine sponge, for enzyme variants capable of synthesizing silicon dioxide (silica) or titanium dioxide (titania) composites. Mineral composites of intermediate strength are preferentially selected to remain intact for identification during cell sorting, and then to collapse postsorting to expose the encoding genes for enzymatic DNA amplification. Some of the newly selected silicatein variants catalyze the formation of crystalline silicates, whereas the parent silicateins lack this ability. The demonstrated bioengineered route to previously undescribed materials introduces in vitro enzyme selection as a viable strategy for mimicking genetic evolution of materials as it occurs in nature.

Effects on DPPH inhibition of egg-white protein polypeptides treated by pulsed electric field technology.

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Wang, Ke; Wang, Jia; Liu, Bolong; Lin, Songyi; Zhao, Ping; Liu, Jingbo; Jones, Gregory; Huang, Hsiang-Chi

2013-05-01

Egg-white protein polypeptides are potentially used as a functional ingredient in food products. In this study, the effects on DPPH inhibition of egg-white protein polypeptides ranging from 10 to 30 kDa treated by pulsed electric field (PEF) technology were investigated. 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) inhibition (%) was used to evaluate the antioxidant activity of polypeptides. In order to develop and optimize a pulsed electric field (PEF) mathematical model for improving the antioxidant activity, we have investigated three variables, including concentration (6, 8 and 10 mg mL(-1)), electric field intensity (10, 20 and 30 kV cm(-1)) and pulse frequency (2000, 2350 and 2700 Hz) and subsequently optimized them by response surface methodology (RSM). The concentration (8 mg mL(-1)), electric field intensity (10 kV cm(-1)) and pulse frequency (2000 Hz) were found to be the optimal conditions under which the DPPH inhibition increased 28.44%, compared to the sample without PEF treatment. Both near-infrared spectroscopy (NIR) and mid-infrared spectroscopy (MIR) were used to analyze the change of functional groups. The results showed that PEF technology could improve the antioxidant activity of antioxidant polypeptides from egg-white protein under the optimized conditions. © 2012 Society of Chemical Industry.

Polymer-Block-Polypeptides and Polymer-Conjugated Hybrid Materials as Stimuli-Responsive Nanocarriers for Biomedical Applications.

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John, Johnson V; Johnson, Renjith P; Heo, Min Seon; Moon, Byeong Kyu; Byeon, Seong Jin; Kim, Il

2015-01-01

Stimuli-responsive nanocarriers are a class of soft materials that includes natural polymers, synthetic polymers, and polypeptides. Recently, modern synthesis tools such as atom transfer radical polymerization, reversible addition-fragmentation chain transfer polymerization, nitroxide-mediated radical polymerization, ring-opening polymerization of α-amino acid N-carboxyanhydrides, and various "click" chemistry strategies were simultaneously employed for the design and synthesis of nanosized drug delivery vehicles. Importantly, the research focused on the improvement of the nanocarrier targetability and the site-specific, triggered release of therapeutics with high drug loading efficiency and minimal drug leakage during the delivery to specific targets. In this context, nanocarriers responsive to common stimuli such as pH, temperature, redox potential, light, etc. have been widely used for the controlled delivery of therapeutics to pathological sites. Currently, different synthesis and self-assembly strategies improved the drug loading efficacy and targeted delivery of therapeutic agents to the desired site. In particular, polypeptide-containing hybrid materials have been developed for the controlled delivery of therapeutic agents. Therefore, stimuli-sensitive synthetic polypeptide-based materials have been extensively investigated in recent years. This review focuses on recent advances in the development of polymer-block-polypeptides and polymer-conjugated hybrid materials that have been designed and evaluated for various stimuli-responsive drug and gene delivery applications.

Smart systems related to polypeptide sequences

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Lourdes Franco

2016-03-01

Full Text Available Increasing interest for the application of polypeptide-based smart systems in the biomedical field has developed due to the advantages given by the peptidic sequence. This is due to characteristics of these systems, which include: biocompatibility, potential control of degradation, capability to provide a rich repertoire of biologically specific interactions, feasibility to self-assemble, possibility to combine different functionalities, and capability to give an environmentally responsive behavior. Recently, applications concerning the development of these systems are receiving greater attention since a targeted and programmable release of drugs (e.g. anti-cancer agents can be achieved. Block copolymers are discussed due to their capability to render differently assembled architectures. Hybrid systems based on silica nanoparticles are also discussed. In both cases, the selected systems must be able to undergo fast changes in properties like solubility, shape, and dissociation or swelling capabilities. This review is structured in different chapters which explain the most recent advances on smart systems depending on the stimuli to which they are sensitive. Amphiphilic block copolymers based on polyanionic or polycationic peptides are, for example, typically employed for obtaining pH-responsive systems. Elastin-like polypeptides are usually used as thermoresponsive polymers, but performance can be increased by using techniques which utilize layer-by-layer electrostatic self-assembly. This approach offers a great potential to create multilayered systems, including nanocapsules, with different functionality. Recent strategies developed to get redox-, magnetic-, ultrasound-, enzyme-, light- and electric-responsive systems are extensively discussed. Finally, some indications concerning the possibilities of multi-responsive systems are discussed.

Folding and self-assembly of polypeptides: Dynamics and thermodynamics from molecular simulation

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Fluitt, Aaron Michael

Empowered by their exquisite three-dimensional structures, or "folds," proteins carry out biological tasks with high specificity, efficiency, and fidelity. The fold that optimizes biological function represents a stable configuration of the constituent polypeptide molecule(s) under physiological conditions. Proteins and polypeptides are not static, however: battered by thermal motion, they explore a distribution of folds that is determined by the sequence of amino acids, the presence and identity of other molecules, and the thermodynamic conditions. In this dissertation, we apply molecular simulation techniques to the study of two polypeptides that have unusually diffuse distributions of folds under physiological conditions: polyglutamine (polyQ) and islet amyloid polypeptide (IAPP). Neither polyQ nor IAPP adopts a predominant fold in dilute aqueous solution, but at sufficient concentrations, both are prone to self-assemble into stable, periodic, and highly regular aggregate structures known as amyloid. The appearance of amyloid deposits of polyQ in the brain, and of IAPP in the pancreas, are associated with Huntington's disease and type 2 diabetes, respectively. A molecular view of the mechanism(s) by which polyQ and IAPP fold and self-assemble will enhance our understanding of disease pathogenesis, and it has the potential to accelerate the development of therapeutics that target early-stage aggregates. Using molecular simulations with spatial and temporal resolution on the atomic scale, we present analyses of the structural distributions of polyQ and IAPP under various conditions, both in and out of equilibrium. In particular, we examine amyloid fibers of polyQ, the IAPP dimer in solution, and single IAPP fragments at a lipid bilayer. We also benchmark the molecular models, or "force fields," available for such studies, and we introduce a novel simulation algorithm.

Light Scattering Characterization of Elastin-Like Polypeptide Trimer Micelles

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Tsuper, Ilona; Terrano, Daniel; Maraschky, Adam; Holland, Nolan; Streletzky, Kiril

The elastin-like polypeptides (ELP) nanoparticles are composed of three-armed star polypeptides connected by a negatively charged foldon. Each of the three arms extending from the foldon domain includes 20 repeats of the (GVGVP) amino acid sequence. The ELP polymer chains are soluble at room temperature and become insoluble at the transition temperature (close to 50 ° C), forming micelles. The size and shape of the micelle are dependent on the temperature and the pH of the solution, and on the concentration of the phosphate buffered saline (PBS). The depolarized dynamic light scattering (DDLS) was employed to study the structure and dynamics of micelles at 62 ° C. The solution was maintained at an approximate pH level of 7.3 - 7.5, while varying PBS concentration. At low salt concentrations (60 mM) displayed an apparent elongation of the micelles evident by a significant VH signal, along with a surge in the apparent Rh. A model of micelle growth (and potential elongation) with increase in salt concentration is considered.

In vitro and in vivo phosphorylation of polypeptides in plasma membrane and tonoplast-enriched fractions from barley roots

International Nuclear Information System (INIS)

Garbarino, J.E.; Hurkman, W.J.; Tanaka, C.K.; DuPont, F.M.

1991-01-01

Phosphorylation of polypeptides in membrane fractions from barley (Hordeum vulgare L. cv CM 72) roots was compared in in vitro and in vivo assays to assess the potential role of protein kinases in modification of membrane transport. Membrane fractions enriched in endoplasmic reticulum, tonoplast, and plasma membrane were isolated using sucrose gradients and the membrane polypeptides separated using sodium dodecyl sulfate polyacrylamide gel electrophoresis. When the membrane fractions were incubated with γ[p 32 P]ATP, phosphorylation occurred almost exclusively in the plasma membrane fraction. Phosphorylation of a band at 38 kilodaltons increased as the concentration of Mg 2+ was decreased from millimolar to micromolar levels. Phosphorylation of bands at 125, 86, 58, 46 and 28 kilodaltons required millimolar Mg 2+ concentrations and was greatly enhanced by Ca 2+ . When roots of intact plants were labeled with [ 32 P]orthophosphate, polypeptides at approximately 135, 166, 90, 46 to 53, 32, 28, and 19 kilodaltons were labeled in the plasma membrane fraction and polypeptides at approximately 73, 66, and 48 kilodaltons were labeled in the tonoplast fraction. Treatment of the roots of intact plants with 150 millimolar NaCl resulted in increased phosphorylation of some polypeptides while treatment with 100 mM NaCl had no effect

Identification of the polypeptides encoded in the unassigned reading frames 2, 4, 4L, and 5 of human mitochondrial DNA

International Nuclear Information System (INIS)

Mariottini, P.; Chomyn, A.; Riley, M.; Cottrell, B.; Doolittle, R.F.; Attardi, G.

1986-01-01

In previous work, antibodies prepared against chemically synthesized peptides predicted from the DNA sequence were used to identify the polypeptides encoded in three of the eight unassigned reading frames (URFs) of human mitochondrial DNA (mtDNA). In the present study, this approach has been extended to other human mtDNA URFs. In particular, antibodies directed against the NH 2 -terminal octapeptide of the putative URF2 product specifically precipitated component 11 of the HeLa cell mitochondrial translation products, the reaction being inhibited by the specific peptide. Similarly, antibodies directed against the COOH-terminal nonapeptide of the putative URF4 product reacted specifically with components 4 and 5, and antibodies against a COOH-terminal heptapeptide of the presumptive URF4L product reacted specifically with component 26. Antibodies against the NH 2 -terminal heptapeptide of the putative product of URF5 reacted with component 1, but only to a marginal extent; however, the results of a trypsin fingerprinting analysis of component 1 point strongly to this component as being the authentic product of URF5. The polypeptide assignments to the mtDNA URFs analyzed here are supported by the relative electrophoretic mobilities of proteins 11, 4-5, 26, and 1, which are those expected for the molecular weights predicted from the DNA sequence for the products of URF2, URF4, URF4L, and URF5, respectively. With the present assignment, seven of the eight human mtDNA URFs have been shown to be expressed in HeLa cells

Maternally Sequestered Therapeutic Polypeptides – A New Approach for the Management of Preeclampsia

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Eric eGeorge

2014-09-01

Full Text Available The last several decades have seen intensive research into the molecular mechanisms underlying the symptoms of preeclampsia. While the underlying cause of preeclampsia is believed to be defective placental development and resulting placental ischemia, it is only recently that the links between the ischemic placenta and maternal symptomatic manifestation have been elucidated. Several different pathways have been implicated in the development of the disorder; most notably production of the anti-angiogenic protein sFlt-1, induction of auto-immunity and inflammation, and production of reactive oxygen species. While the molecular mechanisms are becoming clearer, translating that knowledge into effective therapeutics has proven elusive. Here we describe a number of peptide based therapies we have developed to target theses pathways, and which are currently being tested in preclinical models. These therapeutics are based on a synthetic polymeric carrier elastin-like polypeptide (ELP, which can be synthesized in various sequences and sizes to stabilize the therapeutic peptide and avoid crossing the placental interface. This prevents fetal exposure and potential developmental effects. The therapeutics designed will target known pathogenic pathways, and the ELP carrier could prove to be a versatile delivery system for administration of a variety of therapeutics during pregnancy.

In vivo guided vascular regeneration with a non-porous elastin-like polypeptide hydrogel tubular scaffold.

Science.gov (United States)

Mahara, Atsushi; Kiick, Kristi L; Yamaoka, Tetsuji

2017-06-01

Herein, we demonstrate a new approach for small-caliber vascular reconstruction using a non-porous elastin-like polypeptide hydrogel tubular scaffold, based on the concept of guided vascular regeneration (GVR). The scaffolds are composed of elastin-like polypeptide, (Val-Pro-Gly-Ile-Gly) n , for compliance matching and antithrombogenicity and an Arg-Gly-Asp (RGD) motif for connective tissue regeneration. When the polypeptide was mixed with an aqueous solution of β-[Tris(hydroxymethyl)phosphino]propionic acid at 37°C, the polypeptide hydrogel was rapidly formed. The elastic modulus of the hydrogel was 4.4 kPa. The hydrogel tubular scaffold was formed in a mold and reinforced with poly(lactic acid) nanofibers. When tubular scaffolds with an inner diameter of 1 mm and length of 5 mm were implanted into rat abdominal aortae, connective tissue grew along the scaffold luminal surface from the flanking native tissues, resulting in new blood vessel tissue with a thickness of 200 μm in 1 month. In contrast, rats implanted with control scaffolds without the RGD motif died. These results indicate that the non-porous hydrogel tubular scaffold containing the RGD motif effectively induced rapid tissue regeneration and that GVR is a promising strategy for the regeneration of small-diameter blood vessels. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1746-1755, 2017. © 2017 Wiley Periodicals, Inc.

Membrane fractions active in poliovirus RNA replication contain VPg precursor polypeptides

International Nuclear Information System (INIS)

Takegami, T.; Semler, B.L.; Anderson, C.W.; Wimmer, E.

1983-01-01

The poliovirus specific polypeptide P3-9 is of special interest for studies of viral RNA replication because it contains a hydrophobic region and, separated by only seven amino acids from that region, the amino acid sequence of the genome-linked protein VPg. Membraneous complexes of poliovirus-infected HeLa cells that contain poliovirus RNA replicating proteins have been analyzed for the presence of P3-9 by immunoprecipitation. Incubation of a membrane fraction rich in P3-9 with proteinase leaves the C-terminal 69 amino acids of P3-9 intact, an observation suggesting that this portion is protected by its association with the cellular membrane. These studies have also revealed two hitherto undescribed viral polypeptides consisting of amino acid sequences of the P2 andf P3 regions of the polyprotein. Sequence analysis by stepwise Edman degradation show that these proteins are 3b/9 (M/sub r/77,000) and X/9 (M/sub r/50,000). 3b/9 and X/9 are membrane bound and are turned over rapidly and may be direct precursors to proteins P2-X and P3-9 of the RNA replication complex. P2-X, a polypeptide void of hydrophobic amino acid sequences but also found associated with membranes, is rapidly degraded when the membraneous complex is treated with trypsin. It is speculated that P2-X is associated with membranes by its affinity to the N-terminus of P3-9

Nano magnetic solid phase extraction for preconcentration of lead ions in environmental samples by a newly synthesized reagent.

Science.gov (United States)

Golshekan, Mostafa; Shariati, Shahab

2013-01-01

In this study, magnetite nanoparticles with particle size lower than 47 nm were synthesized and were applied for preconcentration of Pb2+ ions from aqueous solutions. To preconcentrate the Pb2+ ions, the surface of the synthesized nano particles was modified with sodium dodecyl sulfate (SDS) as an anionic surfactant. A new chelating agent (2-((E)-2-amino-4,5-dinitrophenylimino)methyl)phenol) was synthesized and used to form a very stable complex with Pb2+ ions. The lead ions formed complexes and were quantitatively extracted with SDS-coated magnetite nanoparticles. After magnetic separation of adsorbent, the adsorbent was eluted with 0.5% (v/v) HC1 in dimethyl sulfoxide (DMSO) prior to analysis by flame atomic absorption spectrometry (FAAS). Orthogonal array design (OAD) was used to study and optimize the different experimental parameters. Under the optimum conditions, enhancement factor up to 63.5 was achieved for extraction from only 10 mL of sample solution and the relative standard deviation (RSD %) of the method was lower than 2.8%. The obtained calibration curve was linear in the range of 1-300 pg L-' with reasonable linearity (r2 > 0.998). The limit of detection (LOD) based on S/N = 3 was 0.04 microg L(-1) for 10 mL sample volumes. Finally, applicability of the proposed method was successfully confirmed by preconcentration and determination of trace amounts of lead ions in environmental samples and satisfactory results were obtained.

Salt- and pH-Triggered Helix-Coil Transition of Ionic Polypeptides under Physiology Conditions.

Science.gov (United States)

Yuan, Jingsong; Zhang, Yi; Sun, Yue; Cai, Zhicheng; Yang, Lijiang; Lu, Hua

2018-06-11

Controlling the helix-coil transition of polypeptides under physiological conditions is an attractive way toward smart functional materials. Here, we report the synthesis of a series of tertiary amine-functionalized ethylene glycol (EG x )-linked polypeptide electrolytes with their secondary structures tunable under physiological conditions. The resultant polymers, denoted as P(EG x DMA-Glu) ( x = 1, 2, and 3), show excellent aqueous solubility (>20 mg/mL) regardless of their charge states. Unlike poly-l-lysine that can form a helix only at pH above 10, P(EG x DMA-Glu) undergo a pH-dependent helix-coil switch with their transition points within the physiological range (pH ∼5.3-6.5). Meanwhile, P(EG x DMA-Glu) exhibit an unusual salt-induced helical conformation presumably owing to the unique properties of EG x linkers. Together, the current work highlights the importance of fine-tuning the linker chemistry in achieving conformation-switchable polypeptides and represents a facile approach toward stimuli-responsive biopolymers for advanced biological applications.

Zonadhesin D3-polypeptides vary among species but are similar in Equus species capable of interbreeding.

Science.gov (United States)

Tardif, Steve; Brady, Heidi A; Breazeale, Kelly R; Bi, Ming; Thompson, Leslie D; Bruemmer, Jason E; Bailey, Laura B; Hardy, Daniel M

2010-02-01

Zonadhesin is a rapidly evolving protein in the sperm acrosome that confers species specificity to sperm-zona pellucida adhesion. Though structural variation in zonadhesin likely contributes to its species-specific function, the protein has not previously been characterized in organisms capable of interbreeding. Here we compared properties of zonadhesin in several animals, including the horse (Equus caballus), donkey (E. asinus), and Grevy's zebra (E. grevyi) to determine if variation in zonadhesin correlates with ability of gametes to cross-fertilize. Zonadhesin localized to the apical acrosomes of spermatozoa from all three Equus species, similar to its localization in other animals. Likewise, in horse and donkey testis, zonadhesin was detected only in germ cells, first in the acrosomal granule of round spermatids and then in the developing acrosomes of elongating spermatids. Among non-Equus species, D3-domain polypeptides of mature, processed zonadhesin varied markedly in size and detergent solubility. However, zonadhesin D3-domain polypeptides in horse, donkey, and zebra spermatozoa exhibited identical electrophoretic mobility and detergent solubility. Equus zonadhesin D3-polypeptides (p110/p80 doublet) were most similar in size to porcine and bovine zonadhesin D3-polypeptides (p105). Sequence comparisons revealed that the horse zonadhesin precursor's domain content and arrangement are similar to those of zonadhesin from other large animals. Partial sequences of horse and donkey zonadhesin were much more similar to each other (>99% identity) than they were to orthologous sequences of human, pig, rabbit, and mouse zonadhesin (52%-72% identity). We conclude that conservation of zonadhesin D3-polypeptide properties correlates with ability of Equus species to interbreed.

Analysis of urine composition in type Ⅱ diabetic mice after intervention therapy using holothurian polypeptides

Science.gov (United States)

Li, Yanyan; Xu, Jiajie; Su, Xiurong

2017-07-01

Hydrolysates and peptide fractions (PF) obtained from sea cucumber with commercial enzyme were studied on the hpyerglycemic and renal protective effects on db/db rats using urine metabolomics. Compared with the control group the polypeptides from the two species could significantly reduce the urine glucose and urea. We also tried to address the compositions of highly expressed urinary proteins using a proteomics approach. They were serum albumins, AMBP proteins, negative trypsin, elastase and urinary protein, GAPDH, a receptor of urokinase-type plasminogen activator (uPAR), and Ig kappa chain C region. We used the electronic nose to quickly detect changes in the volatile substances in mice urine after holothurian polypeptides fed, and the results show it can identify the difference between treatment groups with the control group without overlapping. The protein express mechanism of holothurian polypeptides treating diabetes was discussed, and we suggested these two peptides with the hypoglycemic and renal protective activity might be utilized as nutraceuticals.

cDNA encoding a polypeptide including a hevein sequence

Energy Technology Data Exchange (ETDEWEB)

Raikhel, N.V.; Broekaert, W.F.; Chua, N.H.; Kush, A.

2000-07-04

A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a putative signal sequence of 17 amino acid residues followed by a 187 amino acid polypeptide. The amino-terminal region (43 amino acids) is identical to hevein and shows homology to several chitin-binding proteins and to the amino-termini of wound-induced genes in potato and poplar. The carboxyl-terminal portion of the polypeptide (144 amino acids) is 74--79% homologous to the carboxyl-terminal region of wound-inducible genes of potato. Wounding, as well as application of the plant hormones abscisic acid and ethylene, resulted in accumulation of hevein transcripts in leaves, stems and latex, but not in roots, as shown by using the cDNA as a probe. A fusion protein was produced in E. coli from the protein of the present invention and maltose binding protein produced by the E. coli.

cDNA encoding a polypeptide including a hevein sequence

Energy Technology Data Exchange (ETDEWEB)

Raikhel, N.V.; Broekaert, W.F.; Chua, N.H.; Kush, A.

1999-05-04

A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a putative signal sequence of 17 amino acid residues followed by a 187 amino acid polypeptide. The amino-terminal region (43 amino acids) is identical to hevein and shows homology to several chitin-binding proteins and to the amino-termini of wound-induced genes in potato and poplar. The carboxyl-terminal portion of the polypeptide (144 amino acids) is 74--79% homologous to the carboxyl-terminal region of wound-inducible genes of potato. Wounding, as well as application of the plant hormones abscisic acid and ethylene, resulted in accumulation of hevein transcripts in leaves, stems and latex, but not in roots, as shown by using the cDNA as a probe. A fusion protein was produced in E. coli from the protein of the present invention and maltose binding protein produced by the E. coli. 12 figs.

cDNA encoding a polypeptide including a hevein sequence

Energy Technology Data Exchange (ETDEWEB)

Raikhel, Natasha V. (Okemos, MI); Broekaert, Willem F. (Dilbeek, BE); Chua, Nam-Hai (Scarsdale, NY); Kush, Anil (New York, NY)

1999-05-04

A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a putative signal sequence of 17 amino acid residues followed by a 187 amino acid polypeptide. The amino-terminal region (43 amino acids) is identical to hevein and shows homology to several chitin-binding proteins and to the amino-termini of wound-induced genes in potato and poplar. The carboxyl-terminal portion of the polypeptide (144 amino acids) is 74-79% homologous to the carboxyl-terminal region of wound-inducible genes of potato. Wounding, as well as application of the plant hormones abscisic acid and ethylene, resulted in accumulation of hevein transcripts in leaves, stems and latex, but not in roots, as shown by using the cDNA as a probe. A fusion protein was produced in E. coli from the protein of the present invention and maltose binding protein produced by the E. coli.

cDNA encoding a polypeptide including a hevein sequence

Energy Technology Data Exchange (ETDEWEB)

Raikhel, N.V.; Broekaert, W.F.; Chua, N.H.; Kush, A.

1995-03-21

A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1,018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a putative signal sequence of 17 amino acid residues followed by a 187 amino acid polypeptide. The amino-terminal region (43 amino acids) is identical to hevein and shows homology to several chitin-binding proteins and to the amino-termini of wound-induced genes in potato and poplar. The carboxyl-terminal portion of the polypeptide (144 amino acids) is 74--79% homologous to the carboxyl-terminal region of wound-inducible genes of potato. Wounding, as well as application of the plant hormones abscisic acid and ethylene, resulted in accumulation of hevein transcripts in leaves, stems and latex, but not in roots, as shown by using the cDNA as a probe. A fusion protein was produced in E. coli from the protein of the present invention and maltose binding protein produced by the E. coli. 11 figures.

Side-chain-controlled self-assembly of polystyrene-polypeptide miktoarm star copolymers

KAUST Repository

Junnila, Susanna; Houbenov, Nikolay; Karatzas, A.; Hadjichristidis, Nikolaos; Hirao, Akira; Iatrou, Hermis; Ikkala, Olli T.

2012-01-01

polypeptide-surfactant self-assemblies with β-sheet conformation in PS 2PLL(DS) and PS 2(PLL(DS)) 2 which dominate over the formation of block copolymer scale structures. Differences between the 3- and 4-arm systems illustrate how packing frustration between

Study of local conformation and molecular movements of homo-polypeptides in aqueous solutions by using magnetic resonance and relaxation

International Nuclear Information System (INIS)

Perly, Bruno

1980-01-01

The objective of this research thesis is to study local conformations and mobilities of some typical homo-polypeptides by using techniques of magnetic resonance. By using these techniques, it is possible to make highly local observations of molecular elements which allows very efficient analysis of structural and dynamic properties of several biologically important compounds to be performed, and the study of their interactions. After a presentation of the general properties of the studied polypeptides, of magnetic resonance and of magnetic relaxation, the author presents some elements of macromolecular dynamics and movement models. Then, he reports the study of local conformations and structural transitions, applications of spin marking to the dynamic study of polypeptides, a dynamic study of the polypeptide skeleton under the form of statistic balls, the study of local movements of side chains by using nuclear relaxation, the study of the coupling of movements of main and side chains, and of the nuclear relaxation induced by a radical spin marker

Common spectrum of polypeptides occurs in secretion granule membranes of different exocrine glands

International Nuclear Information System (INIS)

Cameron, R.S.; Cameron, P.L.; Castle, J.D.

1986-01-01

A highly purified membrane preparation from rat parotid secretion granules has been used as a comparative probe to examine the extent of compositional overlap in granule membranes of three other exocrine secretory tissues - pancreatic, lacrimal, and submandibular - from several standpoints. First, indirect immunofluorescent studies using a polyclonal polyspecific anti-parotid granule membrane antiserum has indicated a selective staining of granule membrane profiles in all acinar cells of all tissues. Second, highly purified granule membrane subfractions have been isolated from each exocrine tissue; comparative two-dimensional (isoelectric focusing; SDS) PAGE of radioiodinated granule membranes has identified 10-15 polypeptides of identical pI and apparent molecular mass. These species are likely to be integral membrane components since they are not extracted by either saponin-sodium sulfate or sodium carbonate (pH 11.5) treatments, and they do not have counterparts in the granule content. Finally, the identity among selected parotid and pancreatic radioiodinated granule membrane polypeptides has been documented using two-dimensional peptide mapping of chymotryptic and tryptic digests. These findings clearly indicate that exocrine secretory granules, irrespective of the nature of stored secretion, comprise a type of vesicular carrier with a common (and probably refined) membrane composition. Conceivably, the polypeptides identified carry out general functions related to exocrine secretion

Temperature-dependent morphology of hybrid nanoflowers from elastin-like polypeptides

Energy Technology Data Exchange (ETDEWEB)

Ghosh, Koushik; Balog, Eva Rose M.; Sista, Prakash; Williams, Darrick J.; Martinez, Jennifer S., E-mail: jenm@lanl.gov, E-mail: rcrocha@lanl.gov; Rocha, Reginaldo C., E-mail: jenm@lanl.gov, E-mail: rcrocha@lanl.gov [Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Kelly, Daniel [Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2014-02-01

We report a method for creating hybrid organic-inorganic “nanoflowers” using calcium or copper ions as the inorganic component and a recombinantly expressed elastin-like polypeptide (ELP) as the organic component. Polypeptides provide binding sites for the dynamic coordination with metal ions, and then such noncovalent complexes become nucleation sites for primary crystals of metal phosphates. We have shown that the interaction between the stimuli-responsive ELP and Ca{sup 2+} or Cu{sup 2+}, in the presence of phosphate, leads to the growth of micrometer-sized particles featuring nanoscale patterns shaped like flower petals. The morphology of these flower-like composite structures is dependent upon the temperature of growth and has been characterized by scanning electron microscopy. The composition of nanoflowers has also been analyzed by energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The temperature-dependent morphologies of these hybrid nanostructures, which arise from the controllable phase transition of ELPs, hold potential for morphological control of biomaterials in emerging applications such as tissue engineering and biocatalysis.

Temperature-dependent morphology of hybrid nanoflowers from elastin-like polypeptides

Directory of Open Access Journals (Sweden)

Koushik Ghosh

2014-02-01

Full Text Available We report a method for creating hybrid organic-inorganic “nanoflowers” using calcium or copper ions as the inorganic component and a recombinantly expressed elastin-like polypeptide (ELP as the organic component. Polypeptides provide binding sites for the dynamic coordination with metal ions, and then such noncovalent complexes become nucleation sites for primary crystals of metal phosphates. We have shown that the interaction between the stimuli-responsive ELP and Ca2+ or Cu2+, in the presence of phosphate, leads to the growth of micrometer-sized particles featuring nanoscale patterns shaped like flower petals. The morphology of these flower-like composite structures is dependent upon the temperature of growth and has been characterized by scanning electron microscopy. The composition of nanoflowers has also been analyzed by energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The temperature-dependent morphologies of these hybrid nanostructures, which arise from the controllable phase transition of ELPs, hold potential for morphological control of biomaterials in emerging applications such as tissue engineering and biocatalysis.

Cytoplasmic assembly of snRNP particles from stored proteins and newly transcribed snRNA's in L929 mouse fibroblasts

International Nuclear Information System (INIS)

Sauterer, R.A.; Feeney, R.J.; Zieve, G.W.

1988-01-01

Newly synthesized snRNAs appear transiently in the cytoplasm where they assemble into ribonucleoprotein particles, the snRNP particles, before returning permanently to the interphase nucleus. In this report, bona fide cytoplasmic fractions, prepared by cell enucleation, are used for a quantitative analysis of snRNP assembly in growing mouse fibroblasts. The half-lives and abundances of the snRNP precursors in the cytoplasm and the rates of snRNP assembly are calculated in L929 cells. With the exception of U6, the major snRNAs are stable RNA species; U1 is almost totally stable while U2 has a half-life of about two cell cycles. In contrast, the majority of newly synthesized U6 decays with a half-life of about 15 h. The relative abundances of the newly synthesized snRNA species U1, U2, U3, U4 and U6 in the cytoplasm are determined by Northern hybridization using cloned probes and are approximately 2% of their nuclear abundance. The half-lives of the two major snRNA precursors in the cytoplasm (U1 and U2) are approximately 20 min as determined by labeling to steady state. The relative abundance of the snRNP B protein in the cytoplasm is determined by Western blotting with the Sm class of autoantibodies and is approximately 25% of the nuclear abundance. Kinetic studies, using the Sm antiserum to immunoprecipitate the methionine-labeled snRNP proteins, suggest that the B protein has a half-life of 90 to 120 min in the cytoplasm. These data are discussed and suggest that there is a large pool of more stable snRNP proteins in the cytoplasm available for assembly with the less abundant but more rapidly turning-over snRNAs

Causative factors for formation of toxic islet amyloid polypeptide oligomer in type 2 diabetes mellitus

Directory of Open Access Journals (Sweden)

Jeong HR

2015-11-01

Full Text Available Hye Rin Jeong, Seong Soo A AnDepartment of Bionano Technology, Gachon Medical Research Institute, Gachon University, Gyeonggi-do, Republic of KoreaAbstract: Human islet amyloid polypeptide (h-IAPP is a peptide hormone that is synthesized and cosecreted with insulin from insulin-secreting pancreatic β-cells. Recently, h-IAPP was proposed to be the main component responsible for the cytotoxic pancreatic amyloid deposits in patients with type 2 diabetes mellitus (T2DM. Since the causative factors of IAPP (or amylin oligomer aggregation are not fully understood, this review will discuss the various forms of h-IAPP aggregation. Not all forms of IAPP aggregates trigger the destruction of β-cell function and loss of β-cell mass; however, toxic oligomers do trigger these events. Once these toxic oligomers form under abnormal metabolic conditions in T2DM, they can lead to cell disruption by inducing cell membrane destabilization. In this review, the various factors that have been shown to induce toxic IAPP oligomer formation will be presented, as well as the potential mechanism of oligomer and fibril formation from pro-IAPPs. Initially, pro-IAPPs undergo enzymatic reactions to produce the IAPP monomers, which can then develop into oligomers and fibrils. By this mechanism, toxic oligomers could be generated by diverse pathway components. Thus, the interconnections between factors that influence amyloid aggregation (eg, absence of PC2 enzyme, deamidation, reduction of disulfide bonds, environmental factors in the cell, genetic mutations, copper metal ions, and heparin will be presented. Hence, this review will aid in understanding the fundamental causative factors contributing to IAPP oligomer formation and support studies for investigating novel T2DM therapeutic approaches, such as the development of inhibitory agents for preventing oligomerization at the early stages of diabetic pathology.Keywords: amyloid aggregation, causative factor, IAPP, islet

Zonadhesin D3-Polypeptides Vary among Species but Are Similar in Equus Species Capable of Interbreeding1

Science.gov (United States)

Tardif, Steve; Brady, Heidi A.; Breazeale, Kelly R.; Bi, Ming; Thompson, Leslie D.; Bruemmer, Jason E.; Bailey, Laura B.; Hardy, Daniel M.

2009-01-01

Zonadhesin is a rapidly evolving protein in the sperm acrosome that confers species specificity to sperm-zona pellucida adhesion. Though structural variation in zonadhesin likely contributes to its species-specific function, the protein has not previously been characterized in organisms capable of interbreeding. Here we compared properties of zonadhesin in several animals, including the horse (Equus caballus), donkey (E. asinus), and Grevy's zebra (E. grevyi) to determine if variation in zonadhesin correlates with ability of gametes to cross-fertilize. Zonadhesin localized to the apical acrosomes of spermatozoa from all three Equus species, similar to its localization in other animals. Likewise, in horse and donkey testis, zonadhesin was detected only in germ cells, first in the acrosomal granule of round spermatids and then in the developing acrosomes of elongating spermatids. Among non-Equus species, D3-domain polypeptides of mature, processed zonadhesin varied markedly in size and detergent solubility. However, zonadhesin D3-domain polypeptides in horse, donkey, and zebra spermatozoa exhibited identical electrophoretic mobility and detergent solubility. Equus zonadhesin D3-polypeptides (p110/p80 doublet) were most similar in size to porcine and bovine zonadhesin D3-polypeptides (p105). Sequence comparisons revealed that the horse zonadhesin precursor's domain content and arrangement are similar to those of zonadhesin from other large animals. Partial sequences of horse and donkey zonadhesin were much more similar to each other (>99% identity) than they were to orthologous sequences of human, pig, rabbit, and mouse zonadhesin (52%–72% identity). We conclude that conservation of zonadhesin D3-polypeptide properties correlates with ability of Equus species to interbreed. PMID:19794156

Permanent Electric Dipole-Dipole Interactions in Lyotropic Polypeptide Liquid Crystals

OpenAIRE

MORI, Norio; Norio, MORI; Research Associate, Department of Industrial Chemistry

1981-01-01

The interaction energy between two adjacent α-helical molecules was calculated taking into account for permanent electric dipoles locating orl the helical core of a polymer mainchain in order to explain the cholesteric structure of lyotropic polypeptide liquid crystals. It was concluded that the dipole-dipole interactions were responsible for the formation of the cholesteric structure.

Elastin-like polypeptides: Therapeutic applications for an emerging class of nanomedicines.

Science.gov (United States)

Despanie, Jordan; Dhandhukia, Jugal P; Hamm-Alvarez, Sarah F; MacKay, J Andrew

2016-10-28

Elastin-like polypeptides (ELPs) constitute a genetically engineered class of 'protein polymers' derived from human tropoelastin. They exhibit a reversible phase separation whereby samples remain soluble below a transition temperature (T t ) but form amorphous coacervates above T t . Their phase behavior has many possible applications in purification, sensing, activation, and nanoassembly. As humanized polypeptides, they are non-immunogenic, substrates for proteolytic biodegradation, and can be decorated with pharmacologically active peptides, proteins, and small molecules. Recombinant synthesis additionally allows precise control over ELP architecture and molecular weight, resulting in protein polymers with uniform physicochemical properties suited to the design of multifunctional biologics. As such, ELPs have been employed for various uses including as anti-cancer agents, ocular drug delivery vehicles, and protein trafficking modulators. This review aims to offer the reader a catalogue of ELPs, their various applications, and potential for commercialization across a broad spectrum of fields. Copyright © 2015. Published by Elsevier B.V.

Synthesis, pharmacological evaluation and molecular docking studies of pyrimidinedione based DPP-4 inhibitors as antidiabetic agents

Science.gov (United States)

Jha, Vibhu; Bhadoriya, Kamlendra Singh

2018-04-01

Dipeptidyl peptidase-4 (DPP-4) inhibitors are a class of newly developed antidiabetic drugs that bock DPP-4. DPP-4 is responsible for degradation of incretins harmones such as GLP-1 (Glucagon like Peptide) and GIP (Gastric inhibitory polypeptide) that maintain blood-glucose level. Pyrimidinedione based compounds were designed and synthesized for DPP-4 inhibitory activity. These heterocycles were designed by taking Alogliptin as a reference DPP-4 inhibitors and synthesized as N-methylated and N-benzylated pyrimidinediones. These compounds were subjected to DPP-4 assay, five out of nine synthesized compounds have shown in vitro DPP-4 inhibitory activity in significant range. Further, molecular docking studies of these compounds were performed on DPP-4 subunit and compared with natural DPP-4 inhibitors like Flavone, Resveratrol, Quercetin, Diprotin A. Docking studies have led to the conclusion that there are some identical amino acid interactions as Tyr 666 and Tyr 662, seen in both synthesized compounds and natural DPP-4 inhibitors. This study completely gives a good scope for further derivatisation and optimization of synthesized compounds to get clinical candidate as DPP-4 inhibitor for antidiabetic activity.

Organo-Functionalization of Silicon Nanocrystals Synthesized by Inductively Coupled Plasma Chemical Vapor Deposition

Energy Technology Data Exchange (ETDEWEB)

Lee, Don-Sung; Choe, Dong-Hoe; Jeong, Hyun-Dam [Chonnam National University, Gwangju (Korea, Republic of); Yoo, Seung-Wan; Kim, Jung-Hyung [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

2016-05-15

Octadecyl-terminated silicon nanocrystals (ODE-Si NCs) are obtained via a surface-initiated thermal hydrosilylation reaction on hydride-terminated Si NCs (H-Si NCs). Pristine Si NCs were synthesized at the gram scale by using inductively coupled plasma chemical vapor deposition (ICP-CVD) . The H-Si NCs were produced through a chemical etching process with hydrofluoric acid (HF), ethanol (EtOH), and distilled water (d-H{sub 2}O). The results obtained from X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) indicate that the synthesized Si NCs obtained via ICP-CVD have diamond cubic-structured silicon with a grain size of 10 nm and a densely packed Si NC array consisting of individual NCs. Organo-functionalized Si NCs, i.e., ODE-Si NCs, are well soluble in organic solvent whereas pristine Si NCs synthesized through ICP-CVD are not. The surface chemistry of the ODE-Si NCs was confirmed via Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy ({sup 1}H-NMR), and field emission transmission electron microscopy (FE-TEM). Thereby, these newly synthesized and scalable organo-functionalized Si NCs are applicable as raw materials for practical use in devices by tuning the surface chemistry with various capping molecules.

Characterization of mutants expressing thermostable D1 and D2 polypeptides of photosystem II in the cyanobacterium Synechococcus elongatus PCC 7942.

Science.gov (United States)

Haraguchi, Norihisa; Kaseda, Jun; Nakayama, Yasumune; Nagahama, Kazuhiro; Ogawa, Takahira; Matsuoka, Masayoshi

2018-06-08

Photosystem II complex embedded in thylakoid membrane performs oxygenic photosynthesis where the reaction center D1/D2 heterodimer accommodates all components of the electron transport chain. To express thermostable D1/D2 heterodimer in a cyanobacterium Synechococcus elongatus PCC 7942, we constructed a series of mutant strains whose psbA1 and psbD1 genes encoding, respectively, the most highly expressed D1 and D2 polypeptides were replaced with those of a thermophilic strain, Thermosynechococcus vulcanus. Because the C-terminal 16 amino acid sequences of D1 polypeptides should be processed prior to maturation but diverge from each other, we also constructed the psbA1ΔC-replaced strain expressing a thermostable D1 polypeptide devoid of the C-terminal extension. The psbA1/psbD1-replaced strain showed decreased growth rate and oxygen evolution rate, suggesting inefficient photosystem II. Immunoblot analyses for thermostable D1, D2 polypeptides revealed that the heterologous D1 protein was absent in thylakoid membrane from any mutant strains with psbA1, psbA1ΔC, and psbA1/psbD1-replacements, whereas the heterologous D2 protein was present in thylakoid membrane as well as purified photosystem II complex from the psbA1/psbD1-replaced strain. In the latter strain, the compensatory expression of psbA3 and psbD2 genes was elevated. These data suggest that heterologous D2 polypeptide could be combined with the host D1 polypeptide to form chimeric D1/D2 heterodimer, whereas heterologous D1 polypeptide even without the C-terminal extension was unable to make complex with the host D2 polypeptide. Since the heterologous D1 could not be detected even in the whole cells of psbA1/psbD1-replaced strain, the rapid degradation of unprocessed or unassembled heterologous D1 was implicated. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Double-hydrophobic elastin-like polypeptides with added functional motifs: Self-assembly and cytocompatibility.

Science.gov (United States)

Le, Duc H T; Tsutsui, Yoko; Sugawara-Narutaki, Ayae; Yukawa, Hiroshi; Baba, Yoshinobu; Ohtsuki, Chikara

2017-09-01

We have recently developed a novel double-hydrophobic elastin-like triblock polypeptide called GPG, designed after the uneven distribution of two different hydrophobic domains found in elastin, an extracellular matrix protein providing elasticity and resilience to tissues. Upon temperature trigger, GPG undergoes a sequential self-assembling process to form flexible beaded nanofibers with high homogeneity and excellent dispersibility in water. Given that GPG might be a potential elastin-mimetic material, we sought to explore the biological activities of this block polypeptide. Besides GPG, several functionalized derivatives were also constructed by fusing functional motifs such as KAAK or KAAKGRGDS at the C-terminal of GPG. Although the added motifs affected the kinetics of fiber formation and β-sheet contents, all three GPGs assembled into beaded nanofibers at the physiological temperature. The resulting GPG nanofibers preserved their beaded structures in cell culture medium; therefore, they were coated on polystyrene substrates to study their cytocompatibility toward mouse embryonic fibroblasts, NIH-3T3. Among the three polypeptides, GPG having the cell-binding motif GRGDS derived from fibronectin showed excellent cell adhesion and cell proliferation properties compared to other conventional materials, suggesting its promising applications as extracellular matrices for mammalian cells. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2475-2484, 2017. © 2017 Wiley Periodicals, Inc.

Fibronectin synthesized by a human hepatoma cell line

International Nuclear Information System (INIS)

Glasgow, J.E.; Colman, R.W.

1984-01-01

Fibronectin is a family of immunologically similar glycoproteins which mediate a variety of cell-cell and cell-substratum interactions. It is a constituent of the extracellular matrix of connective tissue and circulates in plasma. When suspension and adherent cultures of a human hepatoma cell line (SK-HEP-1) were incubated in serum-free medium, the resulting conditioned medium contained material which was specifically immunoprecipitated by antisera to human plasma fibronectin. By double immunodiffusion, a component in the conditioned culture medium was shown to form a line of identity with fibronectin in human plasma and to migrate as an alpha 2- to beta-globulin during immunoelectrophoresis. Human fibronectin was quantified in conditioned medium by electroimmunodiffusion, and was found to increase for at least three days at about 0.1 micrograms/10(6) cells/day. Adherent cultures of SK-HEP-1 cells were incubated with L-[ 35 S]methionine to label newly synthesized proteins. Labeled fibronectin in conditioned medium or in cell extracts comigrated with fibronectin in human plasma as shown by autoradiography following crossed-immunoelectrophoresis. Fibronectin was demonstrated in the extra-cellular matrix of adherent SK-HEP-1 cultures by immunofluorescence. It was shown previously that SK-HEP-1 cells synthesize alpha 1-protease inhibitor, one of the products of normal hepatocytes. The finding that these hepatoma cells also synthesize fibronectin supports the concept that the hepatocyte may be one source of circulating fibronectin, a possibility consistent with the established role of this cell type in blood plasma protein synthesis

Characterization of Newly Synthesized ZrFe2O5 Nanomaterial and Investigations of Its Tremendous Photocatalytic Properties under Visible Light Irradiation

Directory of Open Access Journals (Sweden)

Shaukat Ali Shahid

2013-01-01

Full Text Available High functional ZrFe2O5 nanoparticles were synthesized using coprecipitation technique. The chemical composition of nanomaterials was studied by energy-dispersive X-ray (EDX. To observe the morphology, field emission scanning electron microscopy (FE-SEM was used. X-ray diffraction (XRD technique was utilized to appraise the structure of the synthesized material. The photocatalytic behavior of ZrFe2O5 nano-particles was investigated by measuring the degradation rate of toluidine blue O (TBO dye in aqueous solution in the presence of ZrFe2O5 nano-particles under visible light irradiation. A steady decrease in absorption peak under visible light irradiation was observed by increasing exposure time. The degradation efficiency was observed as 92% after 140 min of exposure to visible light. Besides, ZrFe2O5 nanophotocatalyst could be recovered and recycled easily. The rate of TBO and total organic carbon (TOC removal under visible light irradiation decreased by only 5% and 10%, respectively, after seven cycles of use, demonstrating the high photostability of the synthesized nano-photocatalyst material.

cDNA encoding a polypeptide including a hev ein sequence

Energy Technology Data Exchange (ETDEWEB)

Raikhel, Natasha V. (Okemos, MI); Broekaert, Willem F. (Dilbeek, BE); Chua, Nam-Hai (Scarsdale, NY); Kush, Anil (New York, NY)

2000-07-04

A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1018 nucleotides long and includes an open reading frame of 204 amino acids. The deduced amino acid sequence contains a putative signal sequence of 17 amino acid residues followed by a 187 amino acid polypeptide. The amino-terminal region (43 amino acids) is identical to hevein and shows homology to several chitin-binding proteins and to the amino-termini of wound-induced genes in potato and poplar. The carboxyl-terminal portion of the polypeptide (144 amino acids) is 74-79% homologous to the carboxyl-terminal region of wound-inducible genes of potato. Wounding, as well as application of the plant hormones abscisic acid and ethylene, resulted in accumulation of hevein transcripts in leaves, stems and latex, but not in roots, as shown by using the cDNA as a probe. A fusion protein was produced in E. coli from the protein of the present invention and maltose binding protein produced by the E. coli.

Newly Synthesized Water Soluble Cholinium-Purpurin Photosensitizers and Their Stabilized Gold Nanoparticles as Promising Anticancer Agents

Directory of Open Access Journals (Sweden)

Young Key Shim

2008-05-01

Full Text Available For possible future use in Photodynamic Therapy (PDT and/or Photothermal Therapy (PTT of cancer and screening of cancer cells a new type of ionic liquid photosensitizer –Cholinium-Purpurin-18 (Chol-Pu-18 – was synthesized and small gold (Au nanoparticles, stabilized by this photosensitizer were prepared without adding any particular reducing agents and CTAB. UV-Vis spectroscopy and Transmission Electron Microscopy (TEM were used for characterization of the nanoparticles and FAB-MS and NMR of the ionic liquid choline hydroxide, purpurin carboxylate and their ionic liquid type of photosensitizer were obtained.

Organic anion transporting polypeptide 1B transporters modulate hydroxyurea pharmacokinetics

OpenAIRE

Walker, Aisha L.; Lancaster, Cynthia S.; Finkelstein, David; Ware, Russell E.; Sparreboom, Alex

2013-01-01

Hydroxyurea is currently the only FDA-approved drug that ameliorates the pathophysiology of sickle cell anemia. Unfortunately, substantial interpatient variability in the pharmacokinetics (PK) of hydroxyurea may result in variation of the drug's efficacy. However, little is known about mechanisms that modulate hydroxyurea PK. Recent in vitro studies identifying hydroxyurea as a substrate for organic anion transporting polypeptide (OATP1B) transporters prompted the current investigation assess...

In-situ crosslinkable and self-assembling elastin-like polypeptide block copolymers for cartilage tissue repair

Science.gov (United States)

Lim, Dong Woo

This work describes the development of genetically engineered elastin-like polypeptide (ELP) block copolymers as in-situ gelling scaffolds for cartilage tissue repair. The central hypothesis underlying this work is that ELP based biopolymers can be exploited as injectable biomaterials by rapid chemical crosslinking. To prove this, gene libraries encoding ELP having different molecular weights and amino acid sequences, and ELP block copolymers composed of various ELP blocks having diverse amino acid composition, length, and phase transition behavior were synthesized by recursive directional ligation, expressed in E. Coli and purified by inverse transition cycling. Mannich-type condensation of hydroxymethylphosphines (HMPs) with primary- and secondary-amines of amino acids was developed as a new crosslinking method of polypeptides. Chemically crosslinked ELP hydrogels were formed rapidly in an aqueous solution by reaction of ELPs containing periodic lysine residues with HMPs. The crosslinking density and mechanical property of the ELP hydrogels were controlled at the sequence level by varying the Lys density in ELPs composed of mono-block as well as by segregation of the Lys residues within specific blocks of tri-block architectures. Fibroblasts embedded in ELP hydrogels survived the crosslinking process and were viable after in vitro culture for at least 3 days. The DNA content of fibroblasts within the tri-block gels was significantly higher than that in the mono-block gels at day 3. These results suggest that the HMP crosslinked ELP block copolymer hydrogels show finely tuned mechanical properties and different microenvironments for cell viability as well as potential as in-situ crosslinkable biopolymers for tissue repair applications with load-bearing environments. As an alternative, rheological behavior of the ELP block copolymers and ELP-grafted hyaluronic acids (HAs) as artificial extracellular matrices (ECMs) showed that they were thermally aggregated into

Functional Modification of Thioether Groups in Peptides, Polypeptides, and Proteins

OpenAIRE

Deming, TJ

2017-01-01

Recent developments in the modification of methionine and other thioether-containing residues in peptides, polypeptides, and proteins are reviewed. Properties and potential applications of the resulting functionalized products are also discussed. While much of this work is focused on natural Met residues, modifications at other side-chain residues have also emerged as new thioether-containing amino acids have been incorporated into peptidic materials. Functional modification of thioether-cont...

NMR study of the cooperative behavior of thermotropic model polypeptides

Czech Academy of Sciences Publication Activity Database

Kurková, Dana; Kříž, Jaroslav; Rodríguez-Cabello, J. C.; Arias, F. J.

2007-01-01

Roč. 56, č. 2 (2007), s. 186-194 ISSN 0959-8103 R&D Projects: GA AV ČR IAA400500604 Grant - others:Spanish Ministry of Science and Culture(ES) A002/02; MAT2000-1764-C02; MAT2001-1853-C02-01; MAT2003- Institutional research plan: CEZ:AV0Z40500505 Keywords : thermotropic polymers * cooperativity * synthetic polypeptides Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.557, year: 2007

Molecular mechanism and structure of Trigger Factor bound to the translating ribosome

Science.gov (United States)

Merz, Frieder; Boehringer, Daniel; Schaffitzel, Christiane; Preissler, Steffen; Hoffmann, Anja; Maier, Timm; Rutkowska, Anna; Lozza, Jasmin; Ban, Nenad; Bukau, Bernd; Deuerling, Elke

2008-01-01

Ribosome-associated chaperone Trigger Factor (TF) initiates folding of newly synthesized proteins in bacteria. Here, we pinpoint by site-specific crosslinking the sequence of molecular interactions of Escherichia coli TF and nascent chains during translation. Furthermore, we provide the first full-length structure of TF associated with ribosome–nascent chain complexes by using cryo-electron microscopy. In its active state, TF arches over the ribosomal exit tunnel accepting nascent chains in a protective void. The growing nascent chain initially follows a predefined path through the entire interior of TF in an unfolded conformation, and even after folding into a domain it remains accommodated inside the protective cavity of ribosome-bound TF. The adaptability to accept nascent chains of different length and folding states may explain how TF is able to assist co-translational folding of all kinds of nascent polypeptides during ongoing synthesis. Moreover, we suggest a model of how TF's chaperoning function can be coordinated with the co-translational processing and membrane targeting of nascent polypeptides by other ribosome-associated factors. PMID:18497744

Two-dimensional electrophoretic analysis of transformation-sensitive polypeptides during chemically, spontaneously, and oncogene-induced transformation of rat liver epithelial cells

DEFF Research Database (Denmark)

Wirth, P J; Luo, L D; Fujimoto, Y

1992-01-01

; AFB), spontaneously, and oncogene (v-Ha-ras, v-raf, and v-myc/v-raf)-induced transformation of RLE cells. Two-dimensional mapping of [35S]methionine-labeled whole cell lysate, cell-free in vitro translation products and [32P]orthophosphate-labeled polypeptides revealed subsets of polypeptides specific...... for each transformation modality. A search of the RLE protein database indicated the specific subcellular location for the majority of these transformation-sensitive proteins. Significant alterations in the expression of the extracellular matrix protein, fibronectin, as well as tropomyosin......- and intermediate filament-related polypeptides (vimentin, beta-tubulin, the cytokeratins, and actin) were observed among the various transformant cell lines. Immunoprecipitation and Western immunoblot analysis of tropomyosin expression in four individual AFB-, as well as four spontaneously induced, and each...

Combined spectroscopic, DFT, TD-DFT and MD study of newly synthesized thiourea derivative

Science.gov (United States)

Menon, Vidya V.; Sheena Mary, Y.; Shyma Mary, Y.; Panicker, C. Yohannan; Bielenica, Anna; Armaković, Stevan; Armaković, Sanja J.; Van Alsenoy, Christian

2018-03-01

A novel thiourea derivative, 1-(3-bromophenyl)-3-[3-(trifluoromethyl)phenyl]thiourea (ANF-22) is synthesized and characterized by FTIR, FT-Raman and NMR spectroscopy experimentally and theoretically. A detailed conformational analysis of the title molecule has been conducted in order to locate the lowest energy geometry, which was further subjected to the detailed investigation of spectroscopic, reactive, degradation and docking studies by density functional theory (DFT) calculations and molecular dynamics (MD) simulations. Time dependent DFT (TD-DFT) calculations have been used also in order to simulate UV spectra and investigate charge transfer within molecule. Natural bond orbital analysis has been performed analyzing the charge delocalization and using HOMO and LUMO energies the electronic properties are analyzed. Molecular electrostatic potential map is used for the quantitative measurement of active sites in the molecule. In order to determine the locations possibly prone to electrophilic attacks we have calculated average local ionization energies and mapped them to the electron density surface. Further insight into the local reactivity properties have been obtained by calculation of Fukui functions, also mapped to the electron density surface. Possible degradation properties by the autoxidation mechanism have been assessed by calculations of bond dissociation energies for hydrogen abstraction. Atoms of title molecule with significant interactions with water molecules have been determined by calculations of radial distribution functions. The title compound can be a lead compound for developing new analgesic drug.

Site-specific fluorescent labeling of nascent proteins on the translating ribosome.

Science.gov (United States)

Saraogi, Ishu; Zhang, Dawei; Chandrasekaran, Sandhya; Shan, Shu-ou

2011-09-28

As newly synthesized proteins emerge from the ribosome, they interact with a variety of cotranslational cellular machineries that facilitate their proper folding, maturation, and localization. These interactions are essential for proper function of the cell, and the ability to study these events is crucial to understanding cellular protein biogenesis. To this end, we have developed a highly efficient method to generate ribosome-nascent chain complexes (RNCs) site-specifically labeled with a fluorescent dye on the nascent polypeptide. The fluorescent RNC provides real-time, quantitative information on its cotranslational interaction with the signal recognition particle and will be a valuable tool in elucidating the role of the translating ribosome in numerous biochemical pathways.

Formation of a [sup(99m)Tc]polypeptide hormone: characterization and chemical quality control by ampholyte displacement radiochromatography

International Nuclear Information System (INIS)

Sundrehagen, E.

1983-01-01

Sup(99m)Tc-complexes with the polypeptide hormone secretin in very low concentration were formed by the concentrated hydrochloric acid/vacuum evaporation/gentisic acid method. The sup(99m)Tc-secretin was characterized by a modified ampholyte radiochromatographic procedure, in addition to thin layer chromatography, gel chromatography and paper electrophoresis. High radiochemical purity and specific radioactivity were obtained. In vivo distribution studies were performed, and the conditions necessary for application of [sup(99m)Tc]polypeptides as scintigraphic agents are discussed. (author)

Incretin secretion in obese Korean children and adolescents with newly diagnosed type 2 diabetes.

Science.gov (United States)

Park, So Hyun; Jung, Min Ho; Cho, Won Kyoung; Park, Mi Sun; Suh, Byung Kyu

2016-01-01

The role of incretins in type 2 diabetes is controversial. This study investigated the association between incretin levels in obese Korean children and adolescents newly diagnosed with type 2 diabetes. We performed a 2-hr oral glucose tolerance test (OGTT) in obese children and adolescents with type 2 diabetes and with normal glucose tolerance. Twelve obese children and adolescents with newly diagnosed type 2 diabetes (DM group) and 12 obese age-matched subjects without type 2 diabetes (NDM group) were included. An OGTT was conducted and insulin, C-peptide, glucagon, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) were measured during the OGTT. The mean age of the patients was 13·8 ± 2·0 years, and the mean body mass index (BMI) Z-score was 2·1 ± 0·5. The groups were comparable in age, sex, BMI Z-score and waist:hip ratio. The DM group had significantly lower homeostasis model assessment of β and insulinogenic index values (P 1). The homeostasis model assessment of insulin resistance index was not different between the two groups. Insulin and C-peptide secretions were significantly lower in the DM group than in the NDM group (P 1). Total GLP-1 secretion was significantly higher in the DM group while intact GLP-1 and GIP secretion values were not significantly different between the two groups. Impaired insulin secretion might be important in the pathogenesis of type 2 diabetes in obese Korean children and adolescents, however, which may not be attributed to incretin secretion. © 2015 John Wiley & Sons Ltd.

Induction of a M/sub r/ 21,000 polypeptide in an Arthrobacter Sp. by dye-sensitized photooxidation

International Nuclear Information System (INIS)

Franzi, J.J.

1985-01-01

Irradiation of aerobic cultures of an Arthrobacter species with near-UV light and oxygen induced synthesis of a cell surface protein, M/sub r/ 21,000 polypeptide. Visible light, oxygen and a sensitizing dye were also effective in induction. Far-UV light, bleomycin and nalidixic acid, all inducers of the recA protein in Escherichia coli, were ineffective inducers of this protein. Furthermore, X-irradiation and radical-generating oxidants failed to induce synthesis of the M/sub r/ 21,000 polypeptide. DNA binding dyes proved to be capable of inducing synthesis of this protein or inhibiting dye-mediated stimulation of synthesis of this protein. For example, dGdC-specific dyes (e.g. methylene blue, neutral red, acridine orange or ethidium bromide) were efficient inducers of the M/sub r/ 21,000 polypeptide. Also methylene blue and neutral red were more efficient inducers than were acridine orange or ethidium bromide, which could be explained by the greater dGdC specificity and, possibly by the greater photoreactivity of methylene blue and neutral red. dAdT-specific dyes such as methyl green or daunomycin effectively inhibited dye-mediated induction. Rose bengal is an anionic dye which does not bind to DNA but does mediate the photooxidation of deoxyguanosine residues in DNA. It is an efficient inducer of the M/sub r/ 21,000 polypeptide. Induction with this dye is nearly eliminated when novobiocin, an inhibitor of DNA gyrase (topoisomerase II) which mediates relaxation, is added in conjunction with rose bengal

Induction of a M/sub r/ 21,000 polypeptide in an Arthrobacter Sp. by dye-sensitized photooxidation

Energy Technology Data Exchange (ETDEWEB)

Franzi, J.J.

1985-01-01

Irradiation of aerobic cultures of an Arthrobacter species with near-UV light and oxygen induced synthesis of a cell surface protein, M/sub r/ 21,000 polypeptide. Visible light, oxygen and a sensitizing dye were also effective in induction. Far-UV light, bleomycin and nalidixic acid, all inducers of the recA protein in Escherichia coli, were ineffective inducers of this protein. Furthermore, X-irradiation and radical-generating oxidants failed to induce synthesis of the M/sub r/ 21,000 polypeptide. DNA binding dyes proved to be capable of inducing synthesis of this protein or inhibiting dye-mediated stimulation of synthesis of this protein. For example, dGdC-specific dyes (e.g. methylene blue, neutral red, acridine orange or ethidium bromide) were efficient inducers of the M/sub r/ 21,000 polypeptide. Also methylene blue and neutral red were more efficient inducers than were acridine orange or ethidium bromide, which could be explained by the greater dGdC specificity and, possibly by the greater photoreactivity of methylene blue and neutral red. dAdT-specific dyes such as methyl green or daunomycin effectively inhibited dye-mediated induction. Rose bengal is an anionic dye which does not bind to DNA but does mediate the photooxidation of deoxyguanosine residues in DNA. It is an efficient inducer of the M/sub r/ 21,000 polypeptide. Induction with this dye is nearly eliminated when novobiocin, an inhibitor of DNA gyrase (topoisomerase II) which mediates relaxation, is added in conjunction with rose bengal.

Studies on the site of protein and RNA syntheses in poxvirus-infected cells

Energy Technology Data Exchange (ETDEWEB)

Sakaue, Y [Osaka Univ. (Japan). Research Inst. for Microbial Diseases

1974-04-01

Pulse labelling of short time and the chase of it were conducted to Poxvirus-infected cells using /sup 3/H-uridine and /sup 3/H-leucine with high concentration, and autoradiography (AR) was taken. As the result, protein synthesis, which was in accordance with ''B''-type inclusion, was markedly observed in one-minute labelling at the site of protein synthesis of infected cells. Although the protein synthesis was observed at the peripheral site of ''A''-type inclusion, it was not found within inclusions. However, it was found from the experiment of chase that protein collected markedly within ''B''-type inclusion. They were found that ''B''-type inclusion is the site of Virus DNA synthesis as well as the site of Virus mRNA synthesis, and that it is also absolutely possible for ''B''-type inclusion to synthesize Virus protein. In addition, it was found that ''A''-type inclusion is not the site of synthesis, but newly-synthesized protein.

Studies on the site of protein and RNA syntheses in poxvirus-infected cells

International Nuclear Information System (INIS)

Sakaue, Yoshihiro

1974-01-01

Pulse labelling of short time and the chase of it were conducted to Poxvirus-infected cells using 3 H-uridine and 3 H-leucine with high concentration, and autoradiography (AR) was taken. As the result, protein synthesis, which was in accordance with ''B''-type inclusion, was markedly observed in one-minute labelling at the site of protein synthesis of infected cells. Although the protein synthesis was observed at the peripheral site of ''A''-type inclusion, it was not found within inclusions. However, it was found from the experiment of chase that protein collected markedly within ''B''-type inclusion. They were found that ''B''-type inclusion is the site of Virus DNA synthesis as well as the site of Virus mRNA synthesis, and that it is also absolutely possible for ''B''-type inclusion to synthesize Virus protein. In addition, it was found that ''A''-type inclusion is not the site of synthesis, but newly-synthesized protein. (Ichikawa, K.)

The pathophysiology of diabetes involves a defective amplification of the late-phase insulin response to glucose by glucose-dependent insulinotropic polypeptide-regardless of etiology and phenotype

DEFF Research Database (Denmark)

Vilsbøll, Tina; Knop, F K; Krarup, T

2003-01-01

[maturity-onset diabetes of the young (MODY)3]; and 5) newly diagnosed type 1 diabetic patients. All participants underwent three hyperglycemic clamps (2 h, 15 mM) with continuous infusion of saline, 1 pmol GLP-1 (7-36)amide/kg body weight.min or 4 pmol GIP pmol/kg body weight.min. The early-phase (0-20 min......The effect of the insulinotropic incretin hormone, glucagon-like peptide-1 (GLP-1), is preserved in typical middle-aged, obese, insulin-resistant type 2 diabetic patients, whereas a defective amplification of the so-called late-phase plasma insulin response (20-120 min) to glucose by the other...... incretin hormone, glucose-dependent insulinotropic polypeptide (GIP), is seen in these patients. The aim of the present investigation was to evaluate plasma insulin and C-peptide responses to GLP-1 and GIP in five groups of diabetic patients with etiology and phenotype distinct from the obese type 2...

Quantitative assessments of the distinct contributions of polypeptide backbone amides versus sidechain groups to chain expansion via chemical denaturation

Science.gov (United States)

Holehouse, Alex S.; Garai, Kanchan; Lyle, Nicholas; Vitalis, Andreas; Pappu, Rohit V.

2015-01-01

In aqueous solutions with high concentrations of chemical denaturants such as urea and guanidinium chloride (GdmCl) proteins expand to populate heterogeneous conformational ensembles. These denaturing environments are thought to be good solvents for generic protein sequences because properties of conformational distributions align with those of canonical random coils. Previous studies showed that water is a poor solvent for polypeptide backbones and therefore backbones form collapsed globular structures in aqueous solvents. Here, we ask if polypeptide backbones can intrinsically undergo the requisite chain expansion in aqueous solutions with high concentrations of urea and GdmCl. We answer this question using a combination of molecular dynamics simulations and fluorescence correlation spectroscopy. We find that the degree of backbone expansion is minimal in aqueous solutions with high concentrations denaturants. Instead, polypeptide backbones sample conformations that are denaturant-specific mixtures of coils and globules, with a persistent preference for globules. Therefore, typical denaturing environments cannot be classified as good solvents for polypeptide backbones. How then do generic protein sequences expand in denaturing environments? To answer this question, we investigated the effects of sidechains using simulations of two archetypal sequences with amino acid compositions that are mixtures of charged, hydrophobic, and polar groups. We find that sidechains lower the effective concentration of backbone amides in water leading to an intrinsic expansion of polypeptide backbones in the absence of denaturants. Additional dilution of the effective concentration of backbone amides is achieved through preferential interactions with denaturants. These effects lead to conformational statistics in denaturing environments that are congruent with those of canonical random coils. Our results highlight the role of sidechain-mediated interactions as determinants of the

Effect of Sequence Blockiness on the Morphologies of Surface-grafted Elastin-like Polypeptides

Science.gov (United States)

Albert, Julie; Sintavanon, Kornkanok; Mays, Robin; MacEwan, Sarah; Chilkoti, Ashutosh; Genzer, Jan

2014-03-01

The inter- and intra- molecular interactions among monomeric units of copolymers and polypeptides depend strongly on monomer sequence distribution and dictate the phase behavior of these species both in solution and on surfaces. To study the relationship between sequence and phase behavior, we have designed a series of elastin-like polypeptides (ELPs) with controlled monomer sequences that mimic copolymers with various co-monomer sequence distributions and attached them covalently to silicon substrates from buffer solutions at temperatures below and above the bulk ELPs' lower critical solution temperatures (LCSTs). The dependence of ELP grafting density on solution temperature was examined by ellipsometry and the resultant surface morphologies were examined in air and under water with atomic force microscopy. Depositions performed above the LCST resulted in higher grafting densities and greater surface roughness of ELPs relative to depositions carried out below the LCST. In addition, we are using gradient substrates to examine the effect of ELP grafting density on temperature responsiveness.

Serological Reactivity and Identification of Immunoglobulin E-Binding Polypeptides of Ganoderma applanatum Crude Spore Cytoplasmic Extract in Puerto Rican Subjects.

Science.gov (United States)

Vilá-Héreter, Frances; Rivera-Mariani, Félix E; Bolaños-Rosero, Benjamín

2017-01-01

The allergenic potential of Ganoderma applanatum basidiospores has been demonstrated previously in Puerto Rico. However, basidiomycete allergens are not available for inclusion in allergy diagnostic panels. Therefore, we sought to confirm allergic sensitization to G. applanatum crude spore cytoplasmic extract through reactivity in serological assays and detection of immunoglobulin E (IgE)-binding polypeptides. Via an indirect ELISA, serological reactivity was compared between groups of individuals with different allergic profiles. Group 1 (n = 51) consisted of individuals with sIgE to the allergens included in the diagnostic panels; group 2 (n = 14) comprised individuals with no sIgE to the allergens tested; and group 3 (n = 22) included individuals with no allergic history. To visualize IgE-binding polypeptides, group 1 sera were examined via Western blotting (WB). Polypeptide bands with the highest reactivity were analyzed by mass spectrometry (MS) for putative identification. The serological reactivity of group 1 was significantly higher than that of group 3 in an indirect ELISA (p = 0.03). Sixty-five percent of group 1 individuals showed reactivity to polypeptide bands in WB. Bands of 81 and 56 kDa had the highest reactivity proportions among the reactive sera, followed by a 45-kDa band. MS analysis of these 3 polypeptides suggests that they are basidiomycete-derived enzymes with aconitate hydratase, catalase, and enolase functions. G. applanatum spores have allergenic components recognized by Puerto Rican individuals, which could eventually be considered as markers in cases of fungal allergy and be included in diagnostic allergen panels in Puerto Rico and tropical regions. © 2017 S. Karger AG, Basel.

Accelerated evolution of the pituitary adenylate cyclase-activating polypeptide precursor gene during human origin

DEFF Research Database (Denmark)

Wang, Yin-Qiu; Qian, Ya-Ping; Yang, Su

2005-01-01

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide abundantly expressed in the central nervous system and involved in regulating neurogenesis and neuronal signal transduction. The amino acid sequence of PACAP is extremely conserved across vertebrate species, indicating a...

Membrane polypeptide in rabbit erythrocytes associated with the inhibition of L-lactate transport by a synthetic anhydride of lactic acid

International Nuclear Information System (INIS)

Donovan, J.A.; Jennings, M.L.

1985-01-01

The synthetic lactyl anhydride isobutylcarbonyl lactyl anhydride (iBCLA), a selective and potent inhibitor of L-(+)-lactate transport in rabbit erythrocytes, reduces the chemical labeling of a 40-50-kdalton polypeptide by tritiated 4,4'-diisothiocyanato-2,2'-dihydrostilbenedisulfonate ([ 3 H]H 2 DIDS). iBCLA does so in a dose-dependent manner at concentrations that strongly inhibit lactate-lactate exchange but not chloride-phosphate exchange. These labeling experiments and inhibition reversal studies using iBCLA, p-(chloro-mercuri)benzenesulfonic acid (pCMBS), and dithiothreitol (DDT) suggest that iBCLA does not act at sulfhydryl groups but at or near an amino group that is near a disulfide linkage in the polypeptide which catalyzes lactate transport. These experiments support the association between specific monocarboxylate transport and a 40-50-kdalton membrane-bound polypeptide of the rabbit erythrocyte

Characterization of cell surface polypeptides of unfertilized, fertilized, and protease-treated zona-free mouse eggs

International Nuclear Information System (INIS)

Boldt, J.; Gunter, L.E.; Howe, A.M.

1989-01-01

The polypeptide composition of unfertilized, fertilized, and protease-treated zona-free mouse eggs was evaluated in this study. Zona-free eggs were radioiodinated by an Iodogen-catalyzed reaction. Light microscopic autoradiography of egg sections revealed that labeling was restricted to the cell surface. Labeled eggs were solubilized, and cell surface polypeptides were identified by one-dimensional SDS polyacrylamide gel electrophoresis and autoradiography. The unfertilized egg demonstrated 8-10 peptides that incorporated 125 I, with major bands observed at approximately 145-150, 94, and 23 kilodaltons (kD). Zona-free eggs fertilized in vitro and then radiolabeled demonstrated several new bands in comparison to unfertilized eggs, with a major band appearing at approximately 36 kD. Treatment of radiolabeled unfertilized eggs with either trypsin or chymotrypsin (1 mg/ml for 5-20 min) caused enzyme-specific modifications in labeled polypeptides. Trypsin (T) treatment resulted in time-dependant modification of the three major peptides at 145-150, 94, and 23 kD. Chymotrypsin (CT) treatment, in contrast, was associated with loss or modification of the 94 kD band, with no apparent effect on either the 145-150 or 23 kD band. Taken together with previous data indicating that T or CT egg treatment interferes with sperm-egg attachment and fusion, these results suggest a possible role for the 94 kD protein in sperm-egg interaction

Syntheses and anti-microbial evaluation of new quinoline scaffold derived pyrimidine derivatives

Directory of Open Access Journals (Sweden)

Shikha S. Dave

2016-09-01

Full Text Available A series of diversely substituted chalcones derived from a quinoline scaffold, e.g. (E-3-(2-chloroquinolin-3-yl-1-(2-hydroxyphenyl prop-2-en-1-one and its pyrimidine analogues e.g. 2-[2-amino-6-(2-chloroquinolin-3-yl-5,6-dihydropyrimidin-4-yl]phenols have been prepared by condensation of 2-chloro-3-formyl quinoline with differently substituted 2-hydroxy acetophenones and further treatment with guanidine carbonate. All the newly synthesized compounds have been evaluated for their in vitro growth inhibitory activity against Escherichia coli, Pseudomonas vulgaris, Bacillus subtilis, Staphylococcus aureus, Staphylococcus typhi, Candida albicans, Aspergillus niger and Pseudomonas chrysogenum.

Pituitary adenylate cyclase-activating polypeptide stimulates renin secretion via activation of PAC1 receptors

DEFF Research Database (Denmark)

Hautmann, Matthias; Friis, Ulla G; Desch, Michael

2007-01-01

Besides of its functional role in the nervous system, the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) is involved in the regulation of cardiovascular function. Therefore, PACAP is a potent vasodilator in several vascular beds, including the renal vasculature. Because...

Preparation of Photocrosslinked Fish Elastin Polypeptide/Microfibrillated Cellulose Composite Gels with Elastic Properties for Biomaterial Applications

Directory of Open Access Journals (Sweden)

Shinya Yano

2015-01-01

Full Text Available Photocrosslinked hydrogels reinforced by microfibrillated cellulose (MFC were prepared from a methacrylate-functionalized fish elastin polypeptide and MFC dispersed in dimethylsulfoxide (DMSO. First, a water-soluble elastin peptide with a molecular weight of ca. 500 g/mol from the fish bulbus arteriosus was polymerized by N,N′-dicyclohexylcarbodiimide (DCC, a condensation reagent, and then modified with 2-isocyanatoethyl methacrylate (MOI to yield a photocrosslinkable fish elastin polypeptide. The product was dissolved in DMSO and irradiated with UV light in the presence of a radical photoinitiator. We obtained hydrogels successfully by substitution of DMSO with water. The composite gel with MFC was prepared by UV irradiation of the photocrosslinkable elastin polypeptide mixed with dispersed MFC in DMSO, followed by substitution of DMSO with water. The tensile test of the composite gels revealed that the addition of MFC improved the tensile properties, and the shape of the stress–strain curve of the composite gel became more similar to the typical shape of an elastic material with an increase of MFC content. The rheology measurement showed that the elastic modulus of the composite gel increased with an increase of MFC content. The cell proliferation test on the composite gel showed no toxicity.

Wall-associated kinase-like polypeptide mediates nutritional status perception and response

Science.gov (United States)

Yang, Zhenbiao; Karr, Stephen

2014-02-11

The disclosure relates to methods for modulating plant growth and organogenesis using dominant-negative receptor-like kinases. The disclosure further provides a method for increasing plant yield relative to corresponding wild type plants comprising modulating the expression in a plant of a nucleic acid encoding a Wall-Associated Kinase-like 14 polypeptide or a homolog thereof, and selecting for plants having increased yield or growth on a nutrient deficient substrate.

Sustained Release of Antibiotics from Injectable and Thermally Responsive Polypeptide Depots

OpenAIRE

Adams, Samuel B.; Shamji, Mohammed F.; Nettles, Dana L.; Hwang, Priscilla; Setton, Lori A.

2009-01-01

Biodegradable polymeric scaffolds are of interest for delivering antibiotics to local sites of infection in orthopaedic applications, such as bone and diarthrodial joints. The objective of this study was to develop a biodegradable scaffold with ease of drug loading in aqueous solution, while providing for drug depot delivery via syringe injection. Elastin-like polypeptides (ELPs) were used for this application, biopolymers of repeating pentapeptide sequences that were thermally triggered to u...

Prohormone convertase 1/3 is essential for processing of the glucose-dependent insulinotropic polypeptide precursor

DEFF Research Database (Denmark)

Ugleholdt, Randi; Poulsen, Marie-Louise H; Holst, Peter J

2006-01-01

The physiology of the incretin hormones, glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), and their role in type 2 diabetes currently attract great interest. Recently we reported an essential role for prohormone convertase (PC) 1/3 in the cleavage of intesti......The physiology of the incretin hormones, glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), and their role in type 2 diabetes currently attract great interest. Recently we reported an essential role for prohormone convertase (PC) 1/3 in the cleavage....../3 is essential and sufficient for the production of the intestinal incretin hormone GIP, whereas PC2, although capable of cleaving proGIP, does not participate in intestinal proGIP processing and is not found in intestinal GIP-expressing cells....

Self-assembling chimeric polypeptide-doxorubicin conjugate nanoparticles that abolish tumours after a single injection

Science.gov (United States)

Andrew Mackay, J.; Chen, Mingnan; McDaniel, Jonathan R.; Liu, Wenge; Simnick, Andrew J.; Chilkoti, Ashutosh

2009-12-01

New strategies to self-assemble biocompatible materials into nanoscale, drug-loaded packages with improved therapeutic efficacy are needed for nanomedicine. To address this need, we developed artificial recombinant chimeric polypeptides (CPs) that spontaneously self-assemble into sub-100-nm-sized, near-monodisperse nanoparticles on conjugation of diverse hydrophobic molecules, including chemotherapeutics. These CPs consist of a biodegradable polypeptide that is attached to a short Cys-rich segment. Covalent modification of the Cys residues with a structurally diverse set of hydrophobic small molecules, including chemotherapeutics, leads to spontaneous formation of nanoparticles over a range of CP compositions and molecular weights. When used to deliver chemotherapeutics to a murine cancer model, CP nanoparticles have a fourfold higher maximum tolerated dose than free drug, and induce nearly complete tumour regression after a single dose. This simple strategy can promote co-assembly of drugs, imaging agents and targeting moieties into multifunctional nanomedicines.

Elastin-like Polypeptide Linkers for Single-Molecule Force Spectroscopy.

Science.gov (United States)

Ott, Wolfgang; Jobst, Markus A; Bauer, Magnus S; Durner, Ellis; Milles, Lukas F; Nash, Michael A; Gaub, Hermann E

2017-06-27

Single-molecule force spectroscopy (SMFS) is by now well established as a standard technique in biophysics and mechanobiology. In recent years, the technique has benefitted greatly from new approaches to bioconjugation of proteins to surfaces. Indeed, optimized immobilization strategies for biomolecules and refined purification schemes are being steadily adapted and improved, which in turn has enhanced data quality. In many previously reported SMFS studies, poly(ethylene glycol) (PEG) was used to anchor molecules of interest to surfaces and/or cantilever tips. The limitation, however, is that PEG exhibits a well-known trans-trans-gauche to all-trans transition, which results in marked deviation from standard polymer elasticity models such as the worm-like chain, particularly at elevated forces. As a result, the assignment of unfolding events to protein domains based on their corresponding amino acid chain lengths is significantly obscured. Here, we provide a solution to this problem by implementing unstructured elastin-like polypeptides as linkers to replace PEG. We investigate the suitability of tailored elastin-like polypeptides linkers and perform direct comparisons to PEG, focusing on attributes that are critical for single-molecule force experiments such as linker length, monodispersity, and bioorthogonal conjugation tags. Our results demonstrate that by avoiding the ambiguous elastic response of mixed PEG/peptide systems and instead building the molecular mechanical systems with only a single bond type with uniform elastic properties, we improve data quality and facilitate data analysis and interpretation in force spectroscopy experiments. The use of all-peptide linkers allows alternative approaches for precisely defining elastic properties of proteins linked to surfaces.

Comb-like amphiphilic polypeptide-based copolymer nanomicelles for co-delivery of doxorubicin and P-gp siRNA into MCF-7 cells

Energy Technology Data Exchange (ETDEWEB)

Suo, Aili, E-mail: ailisuo@mail.xjtu.edu.cn [Department of Oncology, The First Affiliated Hospital of Xi' an Jiaotong University, Xi' an 710061 (China); Qian, Junmin, E-mail: jmqian@mail.xjtu.edu.cn [State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049 (China); Zhang, Yaping; Liu, Rongrong; Xu, Weijun [State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049 (China); Wang, Hejing [Department of Oncology, The First Affiliated Hospital of Xi' an Jiaotong University, Xi' an 710061 (China)

2016-05-01

A comb-like amphiphilic copolymer methoxypolyethylene glycol-graft-poly(L-lysine)-block-poly(L-phenylalanine) (mPEG-g-PLL-b-Phe) was successfully synthesized. To synthesize mPEG-g-PLL-b-Phe, diblock copolymer PLL-b-Phe was first synthesized by successive ring-opening polymerization of α-amino acid N-carboxyanhydrides followed by the removal of benzyloxycarbonyl protecting groups, and then mPEG was grafted onto PLL-b-Phe by reductive amination via Schiff's base formation. The chemical structures of the copolymers were identified by {sup 1}H NMR. mPEG-g-PLL-b-Phe copolymer had a critical micelle concentration of 6.0 mg/L and could self-assemble in an aqueous solution into multicompartment nanomicelles with a mean diameter of approximately 78 nm. The nanomicelles could encapsulate doxorubicin (DOX) through hydrophobic and π–π stacking interactions between DOX molecules and Phe blocks and simultaneously complex P-gp siRNA with cationic PLL blocks via electrostatic interactions. The DOX/P-gp siRNA-loaded nanomicelles showed spherical morphology, possessed narrow particle size distribution and had a mean particle size of 120 nm. The DOX/P-gp siRNA-loaded nanomicelles exhibited pH-responsive release behaviors and displayed accelerated release under acidic conditions. The DOX/P-gp siRNA-loaded nanomicelles were efficiently internalized into MCF-7 cells, and DOX released could successfully reach nuclei. In vitro cytotoxicity assay demonstrated that the DOX/P-gp siRNA-loaded nanomicelles showed a much higher cytotoxicity in MCF-7 cells than DOX-loaded nanomicelles due to their synergistic killing effect and that the blank nanomicelles had good biocompatibility. Thus, the novel comb-like mPEG-g-PLL-b-Phe nanomicelles could be a promising vehicle for co-delivery of chemotherapeutic drug and genetic material. - Highlights: • Comb-like amphiphilic copolymer mPEG-g-PLL-b-Phe was successfully synthesized. • Polypeptide-based copolymer could self-assemble into

N-terminal and C-terminal heparin-binding domain polypeptides derived from fibronectin reduce adhesion and invasion of liver cancer cells

International Nuclear Information System (INIS)

Tang, Nan-Hong; Chen, Yan-Lin; Wang, Xiao-Qian; Li, Xiu-Jin; Wu, Yong; Zou, Qi-Lian; Chen, Yuan-Zhong

2010-01-01

Fibronectin (FN) is known to be a large multifunction glycoprotein with binding sites for many substances, including N-terminal and C-terminal heparin-binding domains. We investigated the effects of highly purified rhFNHN29 and rhFNHC36 polypeptides originally cloned from the two heparin-binding domains on the adhesion and invasion of highly metastatic human hepatocellular carcinoma cells (MHCC97H) and analyzed the underlying mechanism involved. The MHCC97H cells that adhered to FN in the presence of various concentrations of rhFNHN29 and rhFNHC36 polypeptides were stained with crystal violet and measured, and the effects of rhFNHN29 and rhFNHC36 on the invasion of the MHCC97H cells were then detected using the Matrigel invasion assay as well as a lung-metastasis mouse model. The expression level of integrins and focal adhesion kinase (FAK) phosphotyrosyl protein was examined by Western blot, and the activity of matrix metalloproteinases (MMPs) and activator protein 1 (AP-1) was analyzed by gelatin zymography and the electrophoretic mobility band-shift assay (EMSA), respectively. Both of the polypeptides rhFNHN29 and rhFNHC36 inhibited adhesion and invasion of MHCC97H cells; however, rhFNHC36 exhibited inhibition at a lower dose than rhFNHN29. These inhibitory effects were mediated by integrin αvβ3 and reversed by a protein tyrosine phosphatase inhibitor. Polypeptides rhFNHN29 and rhFNHC36 abrogated the tyrosine phosphorylation of focal adhesion kinase (p-FAK) and activation of activator protein 1 (AP-1), resulting in the decrease of integrin αv, β3 and β1 expression as well as the reduction of MMP-9 activity. Polypeptides rhFNHN29 and rhFNHC36 could potentially be applicable to human liver cancer as anti-adhesive and anti-invasive agents

TISSUE POLYPEPTIDE-SPECIFIC ANTIGEN - A DISCRIMINATIVE PARAMETER BETWEEN PROSTATE-CANCER AND BENIGN PROSTATIC HYPERTROPHY

NARCIS (Netherlands)

MARRINK, J; OOSTEROM, R; BONFRER, HMG; SCHRODER, FH; MENSINK, HJA

1993-01-01

The serum concentration of the cell proliferation marker TPS (tissue polypeptide-specific antigen) was compared with the tumour marker PSA (prostate specific antigen). PSA was found elevated in 50% of the benign prostatic hypertrophy (BPH) patients, in 88% of the patients with active prostate cancer

Primary structure, gene organization and polypeptide expression of poliovirus RNA

Energy Technology Data Exchange (ETDEWEB)

Kitamura, N. (State Univ. of New York, Stony Brook); Semler, B.L.; Rothberg, P.G.

1981-06-18

The primary structure of the poliovirus genome has been determined. The RNA molecule is 7433 nucleotides long, polyadenylated at the 3' terminus, and covalently linked to a small protein (VPg) at the 5' terminus. An open reading frame of 2207 consecutive triplets spans over 89% of the nucleotide sequence and codes for the viral polyprotein NCVPOO. Twelve viral polypeptides have been mapped by amino acid sequence analysis and were found to be proteolytic cleavage products of the polyprotein, cleavages occurring predominantly at Gln-Gly pairs.

High-resolution polypeptide structure and dynamics in anisotropic environments: The gramicidin channel

Energy Technology Data Exchange (ETDEWEB)

Cross, T.A.; Lee, K.C.; Ketchem, R.R.; Hu, W.; Lazo, N.D.; Huo, S. [Florida State Univ., Tallahassee, FL (United States)

1994-12-01

To understand the details of macromolecular function, high-resolution structural and dynamic detail is essential. The polypeptide fold of the gramicidin channel has been effectively modeled for the past 20 years, yet the functional changes in conductance and channel lifetime associated with amino acid substitutions cannot be predicted. To accomplish this goal, high-resolution electrostatic modeling and the precise orientation of all dipoles are required. Furthermore, an enhanced knowledge of the complex molecular environment of this membrane-bound peptide is needed. An aqueous environment is relatively uniform and achiral. The membrane environment is very heterogenous and chiral. A knowledge of the interactions, specific and nonspecific, between peptide and lipid will aid in developing a better understanding of this environment. To accomplish this goal, it is necessary to study the peptide in an extended lipid bilayer, rather than in a vesicular or micellar form. These latter environments are likely to possess increased dynamics, increased water penetration, and distorted interactions between the polypeptide and membrane surface. To perform NMR studies on bilayer bound peptides, solid state NMR methods are required, and for specific site information, isotopic labels are incorporated using solid phase peptide synthesis.

Specific photoaffinity labeling of two plasma membrane polypeptides with an azido auxin

International Nuclear Information System (INIS)

Hicks, G.R.; Rayle, D.L.; Jones, A.M.; Lomax, T.L.

1989-01-01

Plasma membrane vesicles were isolated from zucchini (Cucurbita pepo) hypocotyl tissue by aqueous phase partitioning and assessed for homogeneity by the use of membrane-specific enzyme assays. The highly pure plasma membrane vesicles maintained a pH differential across the membrane and accumulated a tritiated azido analogue of 3-indoleacetic acid (IAA), 5-azido-[7- 3 H]IAA([ 3 H]N 3 IAA), in a manner similar to the accumulation of [ 3 H]IAA. The association of the [ 3 H]N 3 IAA with membrane vesicles was saturable and subject to competition by IAA and auxin analogues. Auxin-binding proteins were photoaffinity labeled by addition of [ 3 H]N 3 IAA to plasma membrane vesicles prior to exposure to UV light and detected by subsequent NaDodSO 4 /PAGE and fluorography. When the reaction temperature was lowered to -196 degree C, high-specific-activity labeling of a 40-kDa and a 42-kDa polypeptide was observed. Collectively, these results suggest that the radiolabeled polypeptides are auxin receptors. The covalent nature of the label should facilitate purification and further characterization of the receptors

The generalized model of polypeptide chain describing the helix-coil transition in biopolymers

International Nuclear Information System (INIS)

Mamasakhlisov, E.S.; Badasyan, A.V.; Tsarukyan, A.V.; Grigoryan, A.V.; Morozov, V.F.

2005-07-01

In this paper we summarize some results of our theoretical investigations of helix-coil transition both in single-strand (polypeptides) and two-strand (polynucleotides) macromolecules. The Hamiltonian of the Generalized Model of Polypeptide Chain (GMPC) is introduced to describe the system in which the conformations are correlated over some dimensional range Δ (it equals 3 for polypeptide, because one H-bond fixes three pairs of rotation, for double strand DNA it equals to one chain rigidity because of impossibility of loop formation on the scale less than Δ). The Hamiltonian does not contain any parameter designed especially for helix-coil transition and uses pure molecular microscopic parameters (the energy of hydrogen bond formation, reduced partition function of repeated unit, the number of repeated units fixed by one hydrogen bond, the energies of interaction between the repeated units and the solvent molecules). To calculate averages we evaluate the partition function using the transfer-matrix approach. The GMPC allowed to describe the influence of a number of factors, affecting the transition, basing on a unified microscopic approach. Thus we obtained, that solvents change transition temperature and interval in different ways, depending on type of solvent and on energy of solvent- macromolecule interaction; stacking on the background of H-bonding increases stability and decreases cooperativity of melting. For heterogeneous DNA we could analytically derive well known formulae for transition temperature and interval. In the framework of GMPC we calculate and show the difference of two order parameters of helix-coil transition - the helicity degree, and the average fraction of repeated units in helical conformation. Given article has the aim to review the results obtained during twenty years in the context of GMPC. (author)

Recombinant DNA specifying the human amyloid. beta. precursor protein (ABPP) encodes a 95-kDa polypeptide

Energy Technology Data Exchange (ETDEWEB)

Mita, S; Sadlock, J; Herbert, J; Schon, E A

1988-10-11

Although the ABPP gene give rise to multiple mRNAs, the primary translation product of this gene is unknown. The longest published cDNA sequences predict a 770-aa polypeptide of 87 kDa. However, in immunoblots, ABPP migrated as a single species of >92 kDa in rat brain, and in human, as a species of 95-100 kDa in non-membrane bound form, as multiple species of 110-135 kDa in membrane-associated form and as a 130-kDa species in fibroblasts. The sizes of these larger species relative to the MW of ABPP predicted from the cDNA sequences have been attributed to postranslational modification. However, the authors have isolated a cDNA (lambdaHAP2) from a human fetal muscle lambdagt11 cDNA library encoding an 843-aa polypeptide with a deduced MW of 94,642. This cDNA contains both exons encoding an 843-aa polypeptide with a deduced MW of 94.642. This cDNA contains both exons encoding the protease inhibitor domains. Primer extension analysis indicates that the 5' terminus of this cDNA is 14 nt from a transcriptional start site. This cDNA, encoding the longest ABPP described to date, may explain some of the observations on the sizes of tissue-derived ABPP.

Peptides, polypeptides and peptide-polymer hybrids as nucleic acid carriers.

Science.gov (United States)

Ahmed, Marya

2017-10-24

Cell penetrating peptides (CPPs), and protein transduction domains (PTDs) of viruses and other natural proteins serve as a template for the development of efficient peptide based gene delivery vectors. PTDs are sequences of acidic or basic amphipathic amino acids, with superior membrane trespassing efficacies. Gene delivery vectors derived from these natural, cationic and cationic amphipathic peptides, however, offer little flexibility in tailoring the physicochemical properties of single chain peptide based systems. Owing to significant advances in the field of peptide chemistry, synthetic mimics of natural peptides are often prepared and have been evaluated for their gene expression, as a function of amino acid functionalities, architecture and net cationic content of peptide chains. Moreover, chimeric single polypeptide chains are prepared by a combination of multiple small natural or synthetic peptides, which imparts distinct physiological properties to peptide based gene delivery therapeutics. In order to obtain multivalency and improve the gene delivery efficacies of low molecular weight cationic peptides, bioactive peptides are often incorporated into a polymeric architecture to obtain novel 'polymer-peptide hybrids' with improved gene delivery efficacies. Peptide modified polymers prepared by physical or chemical modifications exhibit enhanced endosomal escape, stimuli responsive degradation and targeting efficacies, as a function of physicochemical and biological activities of peptides attached onto a polymeric scaffold. The focus of this review is to provide comprehensive and step-wise progress in major natural and synthetic peptides, chimeric polypeptides, and peptide-polymer hybrids for nucleic acid delivery applications.

Tissue polypeptide antigen activity in cerebrospinal fluid

DEFF Research Database (Denmark)

Bach, F; Söletormos, Georg; Dombernowsky, P

1991-01-01

Tissue polypeptide antigen (TPpA) in the cerebrospinal fluid (CSF) was measured in 59 consecutive breast cancer patients with suspected central nervous system (CNS) metastases. Subsequently, we determined that 13 patients had parenchymal brain metastases, 10 had leptomeningeal carcinomatosis......, and 36 had no CNS involvement. The concentration of TPpA, which is a nonspecific marker for cell proliferation, was significantly higher in patients with CNS metastases than in those without it (P less than .0001; Mann-Whitney test). A tentative cutoff value for CNS metastases was set at 95 U/L TPp...... metastases, no correlation was found between TPpA activity in corresponding CSF and blood samples (correlation coefficient, Spearman's rho = .4; P greater than .1). In three patients treated for leptomeningeal carcinomatosis, the measurements of CSF TPpA showed correlation between the presence of tumor cells...

Natural polypeptide scaffolds: beta-sheets, beta-turns, and beta-hairpins.

Science.gov (United States)

Rotondi, Kenneth S; Gierasch, Lila M

2006-01-01

This paper provides an introduction to fundamental conformational states of polypeptides in the beta-region of phi,psi space, in which the backbone is extended near to its maximal length, and to more complex architectures in which extended segments are linked by turns and loops. There are several variants on these conformations, and they comprise versatile scaffolds for presentation of side chains and backbone amides for molecular recognition and designed catalysts. In addition, the geometry of these fundamental folds can be readily mimicked in peptidomimetics. Copyright 2005 Wiley Periodicals, Inc.

Functional Modification of Thioether Groups in Peptides, Polypeptides, and Proteins.

Science.gov (United States)

Deming, Timothy J

2017-03-15

Recent developments in the modification of methionine and other thioether-containing residues in peptides, polypeptides, and proteins are reviewed. Properties and potential applications of the resulting functionalized products are also discussed. While much of this work is focused on natural Met residues, modifications at other side-chain residues have also emerged as new thioether-containing amino acids have been incorporated into peptidic materials. Functional modification of thioether-containing amino acids has many advantages and is a complementary methodology to the widely utilized methods for modification at cysteine residues.

Accumulation of New Polypeptides in Ri T-DNA-Transformed Roots of Tomato (Lycopersicon esculentum) during the Development of Vesicular-Arbuscular Mycorrhizae.

Science.gov (United States)

Simoneau, P; Louisy-Louis, N; Plenchette, C; Strullu, D G

1994-06-01

Root-inducing transferred-DNA (Ri T-DNA)-transformed roots of tomato (Lycopersicon esculentum) were in vitro inoculated with surface-sterilized vesicular-arbuscular mycorrhizal leek root pieces. About 1 week after inoculation, the infection of the transformed root culture by the fungal endophyte was confirmed by photonic microscopy. Total proteins were extracted from the mycorrhizal roots and analyzed by two-dimensional polyacrylamide gel electrophoresis. Control gels were run with proteins extracted from noninoculated roots mixed with purified intraradical vesicles and extraradical hyphae. Comparison of the resulting patterns revealed the presence of two polypeptides with estimated apparent masses of 24 and 39 kDa that were detected only in infected roots. Polypeptides with similar migration parameters were not detected in roots challenged with spore extracts, suggesting that the accumulation of the polypeptides was directly linked to root colonization by the fungus rather than to induction by fungus-derived elicitors.

Polypeptide composition of fraction 1 protein of the somatic hybrid between Petunia parodii and Petunia parviflora.

Science.gov (United States)

Kumar, A; Wilson, D; Cocking, E C

1981-04-01

The analysis of the subunit polypeptide composition of Fraction 1 protein provides information on the expression of both chloroplast and nuclear genomes. Fraction 1 protein, isolated from leaves of the somatic hybrid plants derived form the fusion of protoplasts of Petunia parodii and P. parviflora, was analyzed for its subunit polypeptide composition by isoelectric focusing in 8 M urea. The fraction 1 protein enzyme oligomer in the somatic hybrid plants contained small subunits resulting from the expression of both parental nuclear genomes, but probably only one of the parental large subunits, namely that of P. parodii. The relevance of such somatic hybrid material for the study of nucleocytoplasmic interrelationship is discussed, as well as the use of these fraction 1 protein isoelectric focusing patterns for the analysis of taxonomic relationships in Petunia.

Vasoactive intestinal polypeptide (VIP) in the pig pancreas

DEFF Research Database (Denmark)

Poulsen, Steen Seier

1984-01-01

Vasoactive intestinal polypeptide (VIP) in the pig pancreas is localized to nerves, many of which travel along the pancreatic ducts. VIP stimulates pancreatic fluid and bicarbonate secretion like secretin. Electrical vagal stimulation in the pig causes an atropine-resistant profuse secretion...... of bicarbonate-rich pancreatic juice. In an isolated perfused preparation of the pig pancreas with intact vagal nerve supply, electrical vagal stimulation caused an atropine-resistant release of VIP, which accurately parallelled the exocrine secretion of juice and bicarbonate. Perfusion of the pancreas...... with a potent VIP-antiserum inhibited the effect of vagal stimulation on the exocrine secretion. It is concluded, that VIP is responsible for (at least part of) the neurally controlled fluid and bicarbonate secretion from the pig pancreas....

The Transcriptome of the Zoanthid Protopalythoa variabilis (Cnidaria, Anthozoa) Predicts a Basal Repertoire of Toxin-like and Venom-Auxiliary Polypeptides.

Science.gov (United States)

Huang, Chen; Morlighem, Jean-Étienne Rl; Zhou, Hefeng; Lima, Érica P; Gomes, Paula B; Cai, Jing; Lou, Inchio; Pérez, Carlos D; Lee, Simon Ming; Rádis-Baptista, Gandhi

2016-10-05

Protopalythoa is a zoanthid that, together with thousands of predominantly marine species, such as hydra, jellyfish, and sea anemones, composes the oldest eumetazoan phylum, i.e., the Cnidaria. Some of these species, such as sea wasps and sea anemones, are highly venomous organisms that can produce deadly toxins for preying, for defense or for territorial disputes. Despite the fact that hundreds of organic and polypeptide toxins have been characterized from sea anemones and jellyfish, practically nothing is known about the toxin repertoire in zoanthids. Here, based on a transcriptome analysis of the zoanthid Protopalythoa variabilis, numerous predicted polypeptides with canonical venom protein features are identified. These polypeptides comprise putative proteins from different toxin families: neurotoxic peptides, hemostatic and hemorrhagic toxins, membrane-active (pore-forming) proteins, protease inhibitors, mixed-function venom enzymes, and venom auxiliary proteins. The synthesis and functional analysis of two of these predicted toxin products, one related to the ShK/Aurelin family and the other to a recently discovered anthozoan toxin, displayed potent in vivo neurotoxicity that impaired swimming in larval zebrafish. Altogether, the complex array of venom-related transcripts that are identified in P. variabilis, some of which are first reported in Cnidaria, provides novel insight into the toxin distribution among species and might contribute to the understanding of composition and evolution of venom polypeptides in toxiferous animals. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Radiation hormesis in plant - Analysis and utilization of plant antioxidative mechanism by radiation

Energy Technology Data Exchange (ETDEWEB)

Lee, Haeng Soon; Kwon, Seok Yoon; Shin, Seung Yung [Korea Research Institute of Bioscience and Biotechnology, Taejon (Korea)

2000-04-01

In the tobacco transgenic plants simultaneously expressing SOD and APX in chloroplast, the specific activities of SOD and APX (CA, AM, C/A, A/C) were much higher than in the transgenic plants expressing SOD (CuZnSOD, MnSOD) or APX alone, respectively. Plant growth was severely inhibited showing a well correlation with the dose of gamma-irradiation. In 70 Gy-irradiation, C/A plants showed a slight resistance to gamma radiation. The stAPX gene in tobacco was not as strongly affected by gamma irradiation. After irradiation, the stAPX transcript level decreased at 2 h, then slightly increased at 6 h and the level was maintained until 48 h. Catalase transcripts level decreased at the early time point but at the late time points the level slightly increased. The gamma radiation-induced changes of proteins in tobacco suspension cells were investigated by two-dimensional gel electrophoresis. In the gamma-irradiated cells, a few polypeptides of were newly synthesized, increased, and decreased by comparing total proteins from gamma-irradiated and non-irradiated tobacco suspension cells. With the isolation and analysis of these polypeptides, irradiation-induced proteins could be developed. 35 refs., 5 figs. (Author)

Elastin-like polypeptides: the power of design for smart cell encapsulation.

Science.gov (United States)

Bandiera, Antonella

2017-01-01

Cell encapsulation technology is still a challenging issue. Innovative methodologies such as additive manufacturing, and alternative bioprocesses, such as cell therapeutic delivery, where cell encapsulation is a key tool are rapidly gaining importance for their potential in regenerative medicine. Responsive materials such as elastin-based recombinant expression products have features that are particularly attractive for cell encapsulation. They can be designed and tailored to meet desired requirements. Thus, they represent promising candidates for the development of new concept-based materials that can be employed in this field. Areas covered: An overview of the design and employment of elastin-like polypeptides for cell encapsulation is given to outline the state of the art. Special attention is paid to the design of the macromolecule employed as well as to the method of matrix formation and the biological system involved. Expert opinion: As a result of recent progress in regenerative medicine there is a compelling need for materials that provide specific properties and demonstrate defined functional features. Rationally designed materials that may adapt according to applied external stimuli and that are responsive to biological systems, such as elastin-like polypeptides, belong to this class of smart material. A run through the components described to date represents a good starting point for further advancement in this area. Employment of these components in cell encapsulation application will promote its advance toward 'smart cell encapsulation technology'.

Injectable, Biomolecule-Responsive Polypeptide Hydrogels for Cell Encapsulation and Facile Cell Recovery through Triggered Degradation.

Science.gov (United States)

Xu, Qinghua; He, Chaoliang; Zhang, Zhen; Ren, Kaixuan; Chen, Xuesi

2016-11-16

Injectable hydrogels have been widely investigated in biomedical applications, and increasing demand has been proposed to achieve dynamic regulation of physiological properties of hydrogels. Herein, a new type of injectable and biomolecule-responsive hydrogel based on poly(l-glutamic acid) (PLG) grafted with disulfide bond-modified phloretic acid (denoted as PLG-g-CPA) was developed. The hydrogels formed in situ via enzymatic cross-linking under physiological conditions in the presence of horseradish peroxidase and hydrogen peroxide. The physiochemical properties of the hydrogels, including gelation time and the rheological property, were measured. Particularly, the triggered degradation of the hydrogel in response to a reductive biomolecule, glutathione (GSH), was investigated in detail. The mechanical strength and inner porous structure of the hydrogel were influenced by the addition of GSH. The polypeptide hydrogel was used as a three-dimensional (3D) platform for cell encapsulation, which could release the cells through triggered disruption of the hydrogel in response to the addition of GSH. The cells released from the hydrogel were found to maintain high viability. Moreover, after subcutaneous injection into rats, the PLG-g-CPA hydrogels with disulfide-containing cross-links exhibited a markedly faster degradation behavior in vivo compared to that of the PLG hydrogels without disulfide cross-links, implying an interesting accelerated degradation process of the disulfide-containing polypeptide hydrogels in the physiological environment in vivo. Overall, the injectable and biomolecule-responsive polypeptide hydrogels may serve as a potential platform for 3D cell culture and easy cell collection.

Practicing on Newly Dead

Directory of Open Access Journals (Sweden)

Jewel Abraham

2015-07-01

Full Text Available A newly dead cadaver simulation is practiced on the physical remains of the dead before the onset of rigor mortis. This technique has potential benefits for providing real-life in-situ experience for novice providers in health care practices. Evolving ethical views in health care brings into question some of the ethical aspects associated with newly dead cadaver simulation in terms of justification for practice, autonomy, consent, and the need of disclosure. A clear statement of policies and procedures on newly dead cadaver simulation has yet to be implemented. Although there are benefits and disadvantages to an in-situ cadaver simulation, such practices should not be carried out in secrecy as there is no compelling evidence that suggests such training as imperative. Secrecy in these practices is a violation of honor code of nursing ethics. As health care providers, practitioners are obliged to be ethically honest and trustworthy to their patients. The author explores the ethical aspects of using newly dead cadaver simulation in training novice nursing providers to gain competency in various lifesaving skills, which otherwise cannot be practiced on a living individual. The author explores multiple views on cadaver simulation in relation to ethical theories and practices such as consent and disclosure to family.

Newly synthesized quinazolinone HMJ-38 suppresses angiogenetic responses and triggers human umbilical vein endothelial cell apoptosis through p53-modulated Fas/death receptor signaling

Energy Technology Data Exchange (ETDEWEB)

Chiang, Jo-Hua [Department of Life Sciences, National Chung Hsing University, 250, Kuo-Kuang Road, Taichung 402, Taiwan (China); Yang, Jai-Sing [Department of Pharmacology, China Medical University, Taichung 404, Taiwan (China); Lu, Chi-Cheng [Department of Life Sciences, National Chung Hsing University, 250, Kuo-Kuang Road, Taichung 402, Taiwan (China); Hour, Mann-Jen; Chang, Shu-Jen [School of Pharmacy, China Medical University, Taichung 40402, Taiwan (China); Lee, Tsung-Han, E-mail: thlee@email.nchu.edu.tw [Department of Life Sciences, National Chung Hsing University, 250, Kuo-Kuang Road, Taichung 402, Taiwan (China); Department of Biological Science and Technology, China Medical University, 91, Hsueh-Shih Road, Taichung 404, Taiwan (China); Chung, Jing-Gung, E-mail: jgchung@mail.cmu.edu.tw [Department of Biological Science and Technology, China Medical University, 91, Hsueh-Shih Road, Taichung 404, Taiwan (China); Department of Biotechnology, Asia University, Taichung 413, Taiwan (China)

2013-06-01

The current study aims to investigate the antiangiogenic responses and apoptotic death of human umbilical vein endothelial cells (HUVECs) by a newly synthesized compound named 2-(3′-methoxyphenyl)-6-pyrrolidinyl-4-quinazolinone (HMJ-38). This work attempted to not only explore the effects of angiogenesis on in vivo and ex vivo studies but also hypothesize the implications for HUVECs (an ideal cell model for angiogenesis in vitro) and further undermined apoptotic experiments to verify the underlying molecular signaling by HMJ-38. Our results demonstrated that HMJ-38 significantly inhibited blood vessel growth and microvessel formation by the mouse Matrigel plug assay of angiogenesis, and the suppression of microsprouting from the rat aortic ring assay was observed after HMJ-38 exposure. In addition, HMJ-38 disrupted the tube formation and blocked the ability of HUVECs to migrate in response to VEGF. We also found that HMJ-38 triggered cell apoptosis of HUVECs in vitro. HMJ-38 concentration-dependently suppressed viability and induced apoptotic damage in HUVECs. HMJ-38-influenced HUVECs were performed by determining the oxidative stress (ROS production) and ATM/p53-modulated Fas and DR4/DR5 signals that were examined by flow cytometry, Western blotting, siRNA and real-time RT-PCR analyses, respectively. Our findings demonstrate that p53-regulated extrinsic pathway might fully contribute to HMJ-38-provoked apoptotic death in HUVECs. In view of these observations, we conclude that HMJ-38 reduces angiogenesis in vivo and ex vivo as well as induces apoptosis of HUVECs in vitro. Overall, HMJ-38 has a potent anti-neovascularization effect and could warrant being a vascular targeting agent in the future. - Highlights: • HMJ-38 suppresses angiogenic actions in vivo and ex vivo. • Inhibitions of blood vessel and microvessel formation by HMJ-38 are acted. • Cytotoxic effects of HUVECs occur by HMJ-38 challenge. • p53-modulated extrinsic pathway contributes to HMJ-38

Gastric inhibitory polypeptide (GIP) dose-dependently stimulates glucagon secretion in healthy human subjects at euglycaemia

DEFF Research Database (Denmark)

Meier, J J; Gallwitz, B; Siepmann, N

2003-01-01

AIMS/HYPOTHESIS: In the isolated perfused pancreas, gastric inhibitory polypeptide (GIP) has been shown to enhance glucagon secretion at basal glucose concentrations, but in healthy humans no glucagonotropic effect of GIP has yet been reported. Therefore, we studied the effect of GIP on glucagon ...

Similarities in the induction of synthesis of a cell-surface polypeptide in Arthrobacter sp. by near-UV irradiation and photodynamic conditions

International Nuclear Information System (INIS)

Hoober, J.K.; Franzi, J.

1983-01-01

Irradiation of aerobic suspensions of Arthrobacter sp. with near-UV light (310-400 nm) induced synthesis of a 21 000 dalton, cell-surface polypeptide. Synthesis of this polypeptide also was induced by visible light in the presence of photodynamic dyes. Induction of the polypeptide in ear-UV light and with visible light plus dyes was inhibited by histidine. Hemin inhibited induction in near-UV light and in visible light with methylene blue, neutral red and acriflavin, which are cationic dyes, but failed to inhibit induction in visible light with rose bengal, an anionic dye. These results suggested that inhibition by hemin required electrostatically favored interaction between the anionic porphyrin and the sensitizer, and that the near-UV light effect was mediated by a cationic or neutral endogenous sensitizer. The similarities in the responses of the cells to near-UV irradiation and visible light plus dyes suggested that the mechanism of induction under the two conditions was the same. (author)

N-(2-hydroxy) propyl-3-trimethylammonium chitosan chloride: An immune-enhancing adjuvant for hepatitis E virus recombinant polypeptide vaccine in mice.

Science.gov (United States)

Tao, Wei; Zheng, Hai-Qun; Fu, Ting; He, Zhuo-Jing; Hong, Yan

2017-08-03

Adjuvants are essential for enhancing vaccine potency by improving the humoral and/or cell-mediated immune response to vaccine antigens. This study was performed to evaluate the immuno-enhancing characteristic of N-(2-hydroxy) propyl-3-trimethylammonium chitosan chloride (HTCC), the cationically modified chitosan, as an adjuvant for hepatitis E virus (HEV) recombinant polypeptide vaccine. Animal experiments showed that HTCC provides adjuvant activity when co-administered with HEV recombinant polypeptide vaccine by intramuscularly route. Vaccination using HTCC as an adjuvant was associated with increases of the serum HEV-specific IgG antibodies, splenocytes proliferation and the growths of CD4 + CD8 - T lymphocytes and IFN-γ-secreting T lymphocytes in peripheral blood. These findings suggested that HTCC had strong immuno-enhancing effect. Our findings are the first to demonstrate that HTCC is safe and effective in inducing a good antibody response and stimulating Th1-biased immune responses for HEV recombinant polypeptide vaccine.

The Beads of Translation: Using Beads to Translate mRNA into a Polypeptide Bracelet

Science.gov (United States)

Dunlap, Dacey; Patrick, Patricia

2012-01-01

During this activity, by making beaded bracelets that represent the steps of translation, students simulate the creation of an amino acid chain. They are given an mRNA sequence that they translate into a corresponding polypeptide chain (beads). This activity focuses on the events and sites of translation. The activity provides students with a…

Reaction mechanisms in the radiolysis of peptides, polypeptides and proteins

International Nuclear Information System (INIS)

Garrison, W.M.

1985-01-01

The purpose of this review is to bring together and to correlate the wide variety of experimental studies that provide information on the reaction products and reaction mechanisms involved in the radiolysis of peptides, polypeptides and proteins (including chromosomal proteins) in both aqueous and solid-state systems. The comparative radiation chemistry of these systems is developed in terms of specific reactions of the peptide main-chain and the aliphatic, aromatic-unsaturated and sulfur-containing side-chains. Information obtained with the various experimental techniques of product analysis, competition kinetics, spin-trapping, pulse radiolysis and ESR spectroscopy is included. 147 refs

Reaction mechanisms in the radiolysis of peptides, polypeptides and proteins

Energy Technology Data Exchange (ETDEWEB)

Garrison, W.M.

1985-01-01

The purpose of this review is to bring together and to correlate the wide variety of experimental studies that provide information on the reaction products and reaction mechanisms involved in the radiolysis of peptides, polypeptides and proteins (including chromosomal proteins) in both aqueous and solid-state systems. The comparative radiation chemistry of these systems is developed in terms of specific reactions of the peptide main-chain and the aliphatic, aromatic-unsaturated and sulfur-containing side-chains. Information obtained with the various experimental techniques of product analysis, competition kinetics, spin-trapping, pulse radiolysis and ESR spectroscopy is included. 147 refs.

Analysis of Urine Composition in Type II Diabetic Mice after Intervention Therapy Using Holothurian Polypeptides

Directory of Open Access Journals (Sweden)

Yanyan Li

2017-07-01

Full Text Available Hydrolysates and peptide fractions (PF obtained from sea cucumber with commercial enzyme were studied on the hyperglycemic and renal protective effects on db/db rats using urine metabolomics. Compared with the control group the polypeptides from the two species could significantly reduce the urine glucose and urea. We also tried to address the compositions of highly expressed urinary proteins using a proteomics approach. They were serum albumins, AMBP proteins, negative trypsin, elastase, and urinary protein, GAPDH, a receptor of urokinase-type plasminogen activator (uPAR, and Ig kappa chain C region. We used the electronic nose to quickly detect changes in the volatile substances in mice urine after holothurian polypeptides (HPP fed, and the results show it can identify the difference between treatment groups with the control group without overlapping. The protein express mechanism of HPP treating diabetes was discussed, and we suggested these two peptides with the hypoglycemic and renal protective activity might be utilized as nutraceuticals.

Chemical modification as an approach for the identification of UDPG-binding polypeptides of UDPG-glucose: (1,3)-Beta-glucan synthase

International Nuclear Information System (INIS)

Mason, T.L.

1989-01-01

The lysine-reactive chemical modification reagents uridine diphosphate pyridoxal (UDP-pyridoxal) and formaldehyde (HCHO) were used to identify UDPG-binding polypeptides of UDP-glucose: (1,3)-β-D-glucan synthase (GS) from red beet storage tissue. Complete enzyme inactivation occurred after exposure to micromolar levels of UDP-pyridoxal and millimolar levels of HCHO. Divalent cations (Mg 2+ and Ca 2+ , particularly Ca 2+ ) were required by both for inactivation. Substrate (UDPG) and chelators (EDTA and EGTA) protected plasma membrane GS (PMGS) against UDP-pyridoxal and HCHO inhibition. UDPG protected CHAPS solubilized GS (CSGS) against UDP-pyridoxal inactivation, but not against HCHO. It was concluded that beet GS contains a lysine residue at the UDPG-binding site. When PMGS was directly labeled with UDP[ 3 H]-pyridoxal or [ 14 C]HCHO, random labeling occurred. Therefore, a multi-step labeling procedure was developed. Nonessential lysine residues were first blocked with HCHO while 5 mM UDPG protected the active site lysine. Background labeling was reduced 4-fold. Membranes were recovered by centrifugation and the active site lysine exposed to [ 14 C] HCHO. Major labeled polypeptides were at 200, 76, and 54 kD. Minor polypeptides were seen at 94, 82, 68, 60, and 20-25 kD. CSGS was labeled by a modified multi-step procedure. CSGS was blocked by reaction with UDP-pyridoxal in the presence of UDPG. CSGS was then recovered by product entrapment and labeled with [ 14 C]HCHO. Background labeling was reduced by 8-fold and potential UDPG-binding polypeptides narrowed to 68, 54, 25 and 22 kD

Newly graduated nurses' use of knowledge sources

DEFF Research Database (Denmark)

Voldbjerg, Siri Lygum; Grønkjaer, Mette; Sørensen, Erik Elgaard

2016-01-01

AIM: To advance evidence on newly graduated nurses' use of knowledge sources. BACKGROUND: Clinical decisions need to be evidence-based and understanding the knowledge sources that newly graduated nurses use will inform both education and practice. Qualitative studies on newly graduated nurses' use...... underscoring progression in knowledge use and perception of competence and confidence among newly graduated nurses. CONCLUSION: The transition phase, feeling of confidence and ability to use critical thinking and reflection, has a great impact on knowledge sources incorporated in clinical decisions....... The synthesis accentuates that for use of newly graduated nurses' qualifications and skills in evidence-based practice, clinical practice needs to provide a supportive environment which nurtures critical thinking and questions and articulates use of multiple knowledge sources....

Fibrillar dimer formation of islet amyloid polypeptides

Energy Technology Data Exchange (ETDEWEB)

Chiu, Chi-cheng [Univ. of Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States); de Pablo, Juan J. [Univ. of Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States)

2015-05-08

Amyloid deposits of human islet amyloid polypeptide (hIAPP), a 37-residue hormone co-produced with insulin, have been implicated in the development of type 2 diabetes. Residues 20 – 29 of hIAPP have been proposed to constitute the amyloidogenic core for the aggregation process, yet the segment is mostly unstructured in the mature fibril, according to solid-state NMR data. Here we use molecular simulations combined with bias-exchange metadynamics to characterize the conformational free energies of hIAPP fibrillar dimer and its derivative, pramlintide. We show that residues 20 – 29 are involved in an intermediate that exhibits transient β-sheets, consistent with recent experimental and simulation results. By comparing the aggregation of hIAPP and pramlintide, we illustrate the effects of proline residues on inhibition of the dimerization of IAPP. The mechanistic insights presented here could be useful for development of therapeutic inhibitors of hIAPP amyloid formation.

Fibrillar dimer formation of islet amyloid polypeptides

Directory of Open Access Journals (Sweden)

Chi-cheng Chiu

2015-09-01

Full Text Available Amyloid deposits of human islet amyloid polypeptide (hIAPP, a 37-residue hormone co-produced with insulin, have been implicated in the development of type 2 diabetes. Residues 20 – 29 of hIAPP have been proposed to constitute the amyloidogenic core for the aggregation process, yet the segment is mostly unstructured in the mature fibril, according to solid-state NMR data. Here we use molecular simulations combined with bias-exchange metadynamics to characterize the conformational free energies of hIAPP fibrillar dimer and its derivative, pramlintide. We show that residues 20 – 29 are involved in an intermediate that exhibits transient β-sheets, consistent with recent experimental and simulation results. By comparing the aggregation of hIAPP and pramlintide, we illustrate the effects of proline residues on inhibition of the dimerization of IAPP. The mechanistic insights presented here could be useful for development of therapeutic inhibitors of hIAPP amyloid formation.

Potent and selective mediators of cholesterol efflux

Energy Technology Data Exchange (ETDEWEB)

Bielicki, John K; Johansson, Jan

2015-03-24

The present invention provides a family of non-naturally occurring polypeptides having cholesterol efflux activity that parallels that of full-length apolipoproteins (e.g., Apo AI and Apo E), and having high selectivity for ABAC1 that parallels that of full-length apolipoproteins. The invention also provides compositions comprising such polypeptides, methods of identifying, screening and synthesizing such polypeptides, and methods of treating, preventing or diagnosing diseases and disorders associated with dyslipidemia, hypercholesterolemia and inflammation.

Peptide mediators of cholesterol efflux

Energy Technology Data Exchange (ETDEWEB)

Bielicki, John K.; Johansson, Jan

2013-04-09

The present invention provides a family of non-naturally occurring polypeptides having cholesterol efflux activity that parallels that of full-length apolipoproteins (e.g., Apo AI and Apo E), and having high selectivity for ABAC1 that parallels that of full-length apolipoproteins. The invention also provides compositions comprising such polypeptides, methods of identifying, screening and synthesizing such polypeptides, and methods of treating, preventing or diagnosing diseases and disorders associated with dyslipidemia, hypercholesterolemia and inflammation.

Mathematical Modelling of Glucose-Dependent Insulinotropic Polypeptide and Glucagon-like Peptide-1 following Ingestion of Glucose

DEFF Research Database (Denmark)

Røge, Rikke M; Bagger, Jonatan I; Alskär, Oskar

2017-01-01

The incretin hormones, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), play an important role in glucose homeostasis by potentiating glucose-induced insulin secretion. Furthermore, GLP-1 has been reported to play a role in glucose homeostasis by inhibiting ...

Ascomycin macrolactam derivative SDZ ASM 981 inhibits the release of granule-associated mediators and of newly synthesized cytokines in RBL 2H3 mast cells in an immunophilin-dependent manner.

Science.gov (United States)

Hultsch, T; Müller, K D; Meingassner, J G; Grassberger, M; Schopf, R E; Knop, J

1998-09-01

Mast cells play an important role in the pathological development of many inflammatory and allergic diseases and inhibition of mast cell activation is a potential target for therapeutic intervention. Therefore, the effect of the novel ascomycin macrolactam derivative SDZ ASM 981 on Fc epsilonRI-mediated activation of rat basophilic leukemia (RBL) cells, as a model for mast cell activation, was investigated. First, the ability to inhibit different mast cell immunophilins in vitro was tested. Using recombinant macrophilin-12 (FKBP-12), inhibition of rotamase activity with an IC50 of approximately 6 nM was observed. The rotamase activity of cyclophilin A (18 kDa) was not affected. Secondly, the effect of SDZ ASM 981 on Fc epsilonRI-mediated mast cell activation was investigated in the RBL cell model. SDZ ASM 981 inhibited exocytosis of preformed mediators (e.g. serotonin) with an IC50 of approximately 30 nM. Transcription and release of newly synthesized mediators (e.g. TNF-alpha) was inhibited with an IC50 of approximately 100 nM. The inhibitory effect of SDZ ASM 981 was antagonized by rapamycin. We conclude that SDZ ASM 981 is a potent inhibitor of Fc epsilonRI-mediated activation of mast cells in vitro. The mechanism of action involves formation of (calcineurin) inhibitory complexes with macrophilins. We suggest that this inhibitory action on mast cells might contribute to the antiinflammatory effect of SDZ ASM 981 observed in vivo (e.g. in aptopic dermatitis and psoriasis).

A rat osteogenic cell line (UMR 106-01) synthesizes a highly sulfated form of bone sialoprotein

International Nuclear Information System (INIS)

Midura, R.J.; McQuillan, D.J.; Benham, K.J.; Fisher, L.W.; Hascall, V.C.

1990-01-01

The rat osteosarcoma cell line (UMR 106-01) synthesizes and secretes relatively large amounts of a sulfated glycoprotein into its culture medium (approximately 240 ng/10(6) cells/day). This glycoprotein was purified, and amino-terminal sequence analysis identified it as bone sialoprotein (BSP). [35S]Sulfate, [3H]glucosamine, and [3H]tyrosine were used as metabolic precursors to label the BSP. Sulfate esters were found on N- and O-linked oligosaccharides and on tyrosine residues, with about half of the total tyrosines in the BSP being sulfated. The proportion of 35S activity in tyrosine-O-sulfate (approximately 70%) was greater than that in N-linked (approximately 20%) and O-linked (approximately 10%) oligosaccharides. From the deduced amino acid sequence for rat BSP, the results indicate that on average approximately 12 tyrosine residues, approximately 3 N-linked, and approximately 2 O-linked oligosaccharides are sulfated/molecule. The carboxyl-terminal quarter of the BSP probably contains most, if not all, of the sulfated tyrosine residues because this region of the polypeptide contains the necessary requirements for tyrosine sulfation. Oligosaccharide analyses indicated that for every N-linked oligosaccharide on the BSP, there are also approximately 2 hexa-, approximately 5 tetra-, and approximately 2 trisaccharides O-linked to serine and threonine residues. On average, the BSP synthesized by UMR 106-01 cells would contain a total of approximately 3 N-linked and approximately 25 of the above O-linked oligosaccharides. This large number of oligosaccharides is in agreement with the known carbohydrate content (approximately 50%) of the BSP.A

The synthesis and characterization of polypeptide-adriamycin conjugates and its complexes with adriamycin. Part I

NARCIS (Netherlands)

Heeswijk, W.A.R.; Hoes, C.J.T.; Stoffer, T.; Eenink, M.J.D.; Potman, W.; Feijen, Jan

1985-01-01

Poly(α-l-glutamic acid) (PGA) was grafted with amino acid and oligopeptide spacers up to 5 amino acids with the use of N,N'-carbonyldiimidazole and 2,3-dihydro-1,2-benz-isothiazole-3-on-1, 1-dioxide (saccharin) as an additive, and these polypeptides were characterized. The antitumor antibiotic

Substrate recognition and catalysis by GH47 α-mannosidases involved in Asn-linked glycan maturation in the mammalian secretory pathway

Energy Technology Data Exchange (ETDEWEB)

Xiang, Yong; Karaveg, Khanita; Moremen, Kelley W.

2016-11-17

Asn-linked glycosylation of newly synthesized polypeptides occurs in the endoplasmic reticulum of eukaryotic cells. Glycan structures are trimmed and remodeled as they transit the secretory pathway, and processing intermediates play various roles as ligands for folding chaperones and signals for quality control and intracellular transport. Key steps for the generation of these trimmed intermediates are catalyzed by glycoside hydrolase family 47 (GH47) α-mannosidases that selectively cleave α1,2-linked mannose residues. Despite the sequence and structural similarities among the GH47 enzymes, the molecular basis for residue-specific cleavage remains obscure. The present studies reveal enzyme–substrate complex structures for two related GH47 α-mannosidases and provide insights into how these enzymes recognize the same substrates differently and catalyze the complementary glycan trimming reactions necessary for glycan maturation.

Inhibition of the coated vesicle proton pump and labeling of a 17,000-dalton polypeptide by N,N'-dicyclohexylcarbodiimide

International Nuclear Information System (INIS)

Arai, H.; Berne, M.; Forgac, M.

1987-01-01

N,N'-Dicyclohexylcarbodiimide (DCCD) inhibits 100% of proton transport and 80-85% of (Mg2+)-ATPase activity in clathrin-coated vesicles. Half-maximum inhibition of proton transport is observed at 10 microM DCCD after 30 min. Although treatment of the coated vesicle (H+)-ATPase with DCCD has no effect on ATP hydrolysis in the detergent-solubilized state, sensitivity of proton transport and ATPase activity to DCCD is restored following reconstitution into phospholipid vesicles. In addition, treatment of the detergent-solubilized enzyme with DCCD followed by reconstitution gives a preparation that is blocked in both proton transport and ATP hydrolysis. These results suggest that although the coated vesicle (H+)-ATPase can react with DCCD in either a membrane-bound or detergent-solubilized state, inhibition of ATPase activity is only manifested when the pump is present in sealed membrane vesicles. To identify the subunit responsible for inhibition of the coated vesicle (H+)-ATPase by DCCD, we have labeled the partially purified enzyme with [ 14 C]DCCD. A single polypeptide of molecular weight 17,000 is labeled. The extremely hydrophobic nature of this polypeptide is indicated by its extraction with chloroform:methanol. The 17,000-dalton protein can be labeled to a maximum stoichiometry of 0.99 mol of DCCD/mol of protein with 100% inhibition of proton transport occurring at a stoichiometry of 0.15-0.20 mol of DCCD/mol of protein. Amino acid analysis of the chloroform:methanol extracted 17,000-dalton polypeptide reveals a high percentage of nonpolar amino acids. The similarity in properties of this protein and the DCCD-binding subunit of the coupling factor (H+)-ATPases suggests that the 17,000-dalton polypeptide may function as part of a proton channel in the coated vesicle proton pump

Recycling endosomes in human cytotoxic T lymphocytes constitute an auxiliary intracellular trafficking pathway for newly synthesized perforin

Science.gov (United States)

Lesteberg, Kelsey E.; Orange, Jordan S.; Makedonas, George

2018-01-01

Background Although cytotoxic T lymphocytes (CTLs) store perforin within cytoplasmic secretory granules for immediate use, perforin is synthesized anew within hours of TCR stimulation. Previously, we observed new perforin protein at an immunologic synapse independent of secretory lysosomes; herein we aimed to determine how new perforin transits to the synapse if not via lytic granules. Results We analyzed antigen-specific human CTLs via imaging flow cytometry and high-resolution confocal microscopy, with attention to intracellular trafficking components and new perforin. The recycling endosome compartments identified by rab8, rab11a, rab4, and rab37 co-localized with new perforin, as well as the SNAREs vti1b and VAMP4. After ablating the function of the recycling endosome pathway, we observed a relative accumulation of new perforin in rab8 vesicles. Conclusions The recycling endosome pathway may serve as an auxiliary intracellular route for the delivery of new perforin to an immunologic synapse in order to perpetuate a cytotoxic response. PMID:28822075

Morphological variation of stimuli-responsive polypeptide at air–water interface

International Nuclear Information System (INIS)

Shin, Sungchul; Ahn, Sungmin; Cheng, Jie; Chang, Hyejin; Jung, Dae-Hong; Hyun, Jinho

2016-01-01

Graphical abstract: - Highlights: • It is the first report on the interfacial properties of ELP monolayers formed at the air–water interface. • ELP monolayers could be prepared with high stability at the air–water interface. • The compressive behavior of thermo-sensitive ELP monolayers was imaged. • The SERS spectra showed a change in the ELP secondary structure at different preparation conditions. - Abstract: The morphological variation of stimuli-responsive polypeptide molecules at the air–water interface as a function of temperature and compression was described. The surface pressure–area (π–A) isotherms of an elastin-like polypeptide (ELP) monolayer were obtained under variable external conditions, and Langmuir–Blodgett (LB) monolayers were deposited onto a mica substrate for characterization. As the compression of the ELP monolayer increased, the surface pressure increased gradually, indicating that the ELP monolayer could be prepared with high stability at the air–water interface. The temperature in the subphase of the ELP monolayer was critical in the preparation of LB monolayers. The change in temperature induced a shift in the π–A isotherms as well as a change in ELP secondary structures. Surprisingly, the compression of the ELP monolayer influenced the ELP secondary structure due to the reduction in the phase transition temperature with decreasing temperature. The change in the ELP secondary structure formed at the air–water interface was investigated by surface-enhanced Raman scattering. Moreover, the morphology of the ELP monolayer was subsequently imaged using atomic force microscopy. The temperature responsive behavior resulted in changes in surface morphology from relatively flat structures to rugged labyrinth structures, which suggested conformational changes in the ELP monolayers.

Morphological variation of stimuli-responsive polypeptide at air–water interface

Energy Technology Data Exchange (ETDEWEB)

Shin, Sungchul; Ahn, Sungmin; Cheng, Jie [Department of Biosystems and Biomaterials Science and Engineering, Seoul National University, Seoul 151-921 (Korea, Republic of); Chang, Hyejin; Jung, Dae-Hong [Department of Chemical Education, Seoul National University, Seoul 151-741 (Korea, Republic of); Hyun, Jinho, E-mail: jhyun@snu.ac.kr [Department of Biosystems and Biomaterials Science and Engineering, Seoul National University, Seoul 151-921 (Korea, Republic of); Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921 (Korea, Republic of); Center for Food and Bioconvergence, Seoul National University, Seoul 151-921, Republic of Korea. (Korea, Republic of)

2016-12-01

Graphical abstract: - Highlights: • It is the first report on the interfacial properties of ELP monolayers formed at the air–water interface. • ELP monolayers could be prepared with high stability at the air–water interface. • The compressive behavior of thermo-sensitive ELP monolayers was imaged. • The SERS spectra showed a change in the ELP secondary structure at different preparation conditions. - Abstract: The morphological variation of stimuli-responsive polypeptide molecules at the air–water interface as a function of temperature and compression was described. The surface pressure–area (π–A) isotherms of an elastin-like polypeptide (ELP) monolayer were obtained under variable external conditions, and Langmuir–Blodgett (LB) monolayers were deposited onto a mica substrate for characterization. As the compression of the ELP monolayer increased, the surface pressure increased gradually, indicating that the ELP monolayer could be prepared with high stability at the air–water interface. The temperature in the subphase of the ELP monolayer was critical in the preparation of LB monolayers. The change in temperature induced a shift in the π–A isotherms as well as a change in ELP secondary structures. Surprisingly, the compression of the ELP monolayer influenced the ELP secondary structure due to the reduction in the phase transition temperature with decreasing temperature. The change in the ELP secondary structure formed at the air–water interface was investigated by surface-enhanced Raman scattering. Moreover, the morphology of the ELP monolayer was subsequently imaged using atomic force microscopy. The temperature responsive behavior resulted in changes in surface morphology from relatively flat structures to rugged labyrinth structures, which suggested conformational changes in the ELP monolayers.

Effects of vasoactive intestinal polypeptide on heart rate in relation to vagal cardioacceleration in conscious dogs

NARCIS (Netherlands)

Roossien, A; Brunstig, J.R; Nijmeijer, A; Zaagsma, Hans; Zijlstra, W.G

Objective: The vagal cardiac accelerator (VCA) system takes part in the nervous control of the heart rate. In the present study we tried to adduce evidence that vasoactive intestinal polypeptide (VLP) contributes to vagally induced cardioacceleration. Methods: The effect of VIP on heart rate and

Thermally Targeted Delivery of a c-Myc Inhibitory Peptide In Vivo Using Elastin-like Polypeptide

Science.gov (United States)

2009-10-01

cytoplasm. Also, in a subset of cells, Bac-ELP1⁎-H1 showed very bright nuclear staining exclusive of nucleoli (Fig. 5, lower right, arrows). 3.6. Time...localization was very bright relative to the amount of polypeptide in the cytoplasm, and it appeared to be nucleoplasmic and excluded from nucleoli . The

Hemoglobin variants as models for investigation of dissociation of intact polypeptide chains by ESI tandem mass spectrometry

International Nuclear Information System (INIS)

Light, K.J.; Loo, J.A.; Edmonds, C.G.; Smith, R.D.

1991-06-01

Electrospray ionization mass spectroscopy (ESI-MS) is rapidly becoming a practical biochemical tool for peptide and protein sequence analysis. The utility of ESI-MS is through use of Collisionally Activated Dissociation (ESI-CAD-MS). Human hemoglobin (Hb, ∼62 kDa) consists of four polypeptide chains and a prosthetic heme group. There are over 400 Hb variants, characterized by amino acid substitutions in either the alpha or beta polypeptide chains. We investigated ESI-CAD-MS as a tool for rapidly analyzing amino acid substitutions, using eight Hb beta chain variants. The approximate location of the modification can be deduced from comparison of the CAD mass spectra and observance of the mass shifts of the fragment ion containing the substitution. Fragmentation occurs preferentially at the amino terminus of proline residues. For most substitutions, differences in CAD mass spectra were not seen. 2 figs

Cancer Nano technology Using Elastin-Like Polypeptides

International Nuclear Information System (INIS)

Siti Najila Mohd Janib

2014-01-01

Despite progress in understanding cancer biology, this knowledge has not translated into comparable advances in the clinic. Two fundamental problems currently stalling the efficient treatment of cancer have been detecting cancer early enough for successful treatment and avoiding excessive toxicity to normal tissues. In view of this, cancer still remains one of the leading causes of mortality worldwide, affecting over 10 million new patients every year. Clearly the development of novel approaches for early detection and treatment of cancer is urgently needed to increase patient survival. Recently, nano technology-based systems have emerged as novel therapeutic modalities for cancer treatment. Tiny man made nanoparticles, much smaller than a virus, are being developed to package, transport, and deliver imaging and therapeutic agents. Co-inclusion of these agents, into nano carriers might be advantageous because they increase solubility of hydrophobic drugs, enhance permeability across physiological barriers, alter drug biodistribution, increase local bioavailability and reduce side effects. Initial findings have been promising and nanoparticles have been shown to deliver therapeutic agents to target cells and effect tumor growth. To this end our lab is investigating a class of biodegradable and biocompatible polymers known as elastin-like polypeptides (ELP). Elastin like polypeptide is a bio polymer derived from the structural motif found in mammalian elastin protein and has a sequence dependent transition temperature that can be used as nano carriers to treat diseases. ELPs are characterized by the pentameric repeat VPGXG, where X can be any amino acid. All functional ELPs undergo inverse phase transition whereby below its transition temperature, they exist in a solubilized form while above its transition temperature they undergo phase separation which leads to their aggregation in solution. This process is reversible. Phase transition can also be triggered by other

NMR and rotational angles in solution conformation of polypeptides

Science.gov (United States)

Bystrov, V. F.

1985-01-01

Professor San-Ichiro Mizushima and Professor Yonezo Morino's classical contributions provided unique means and firm basis for understanding of conformational states and internal rotation in polypeptide molecules. Now the NMR spectroscopy is the best choice to study molecular conformation, mechanism of action and structure-functional relationships of peptide and proteins in solution under conditions approaching those of their physiological environments. Crucial details of spatial structure and interactions of these molecules in solution are revealed by using proton-proton and carbon-proton vicinal coupling constants, proton nuclear Overhauser effect and spectral perturbation techniques. The results of NMR conformational analysis are presented for valinomycin "bracelet", gramicidin A double helices, honey-bee neurotoxin apamin, scorpion insectotoxins and snake neurotoxins of long and short types.

Rotation of nucleotide sites is not required for the enzymatic activity of chloroplast coupling factor

Energy Technology Data Exchange (ETDEWEB)

Musier, K.M.; Hammes, G.G.

1987-09-22

New heterobifunctional photoaffinity cross-linking reagents, 6-maleimido-N-(4-benzoylphenyl)hexanamide, 12-maleimido-N-(4-benzoylphenyl)dodecanamide, and 12-(/sup 14/C)maleimido-N-(4-benzoylphenyo)dodecanamide, were synthesized to investigate the mechanism of ATP hydrolysis by chloroplast coupling factor 1. These reagents react with sulfhydryl groups on the ..gamma..-polypeptide. Subsequent photolysis cross-links the ..gamma..-polypeptide covalently to ..cap alpha..- and ..beta..-polypeptides. The cross-linkers prevent major movements of the ..gamma..-polypeptide with respect to the ..cap alpha..- and ..beta..-polypeptides but are sufficiently long to permit some flexibility in the enzyme structure. When approx. 50% of the ..gamma..-polypeptide was cross-linked to a ..cap alpha..- and ..beta..-polypeptides, a 7% loss in ATPase activity was observed for the longer cross-linker and a 12% loss for the shorter. These results indicate that large movements of ..cap alpha..- and ..beta..-polypeptides with respect to the ..gamma..-polypeptide are not essential for catalysis. In particular, rotation of the polypeptide chains to crease structurally equivalent sites during catalysis is not a required feature of the enzyme mechanism.

Design and synthesis of elastin-like polypeptides for an ideal nerve conduit in peripheral nerve regeneration

International Nuclear Information System (INIS)

Hsueh, Yu-Sheng; Savitha, S.; Sadhasivam, S.; Lin, Feng-Huei; Shieh, Ming-Jium

2014-01-01

The study involves design and synthesis of three different elastin like polypeptide (ELP) gene monomers namely ELP1, ELP2 and ELP3 that encode for ELP proteins. The formed ELPs were assessed as an ideal nerve conduit for peripheral nerve regeneration. ELP1 was constructed with a small elongated pentapeptide carrying VPGVG sequence to mimic the natural polypeptide ELP. The ELP2 was designed by the incorporation of 4-penta peptide chains to improve the biocompatibility and mechanical strength. Thus, the third position in unique VPGVG was replaced with alanine to VPAVG and in a similar way modified to VPGKG, VPGEG and VPGIG with the substitution of lysine, glutamic acid and isoleucine. In ELP3, fibronectin C5 domain endowed with REDV sequence was introduced to improve the cell attachment. The ELP1, ELP2 and ELP3 proteins expressed by Escherichia coli were purified by inverse transition cycling (ITC). The purified ELPs were confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting. The Schwann cell (SC) morphology and cell adhesion were assessed by fabrication of ELP membrane cross-linked with glutaraledhyde. The Schwann cell proliferation was measured by WST-1 assay. Immunofluorostaining of Schwann cells was accomplished with SC specific phenotypic marker, S100. - Highlights: • Design and synthesis of three gene monomers of elastin like polypeptides (ELP1, 2 and 3) were reported. • Molecular weight of ITC purified ELP1, ELP2 and ELP3 was in the range of 37–38 kDa. • Schwann cell adhesion was found to be prominent in ELP3 and could be used as nerve conduit for peripheral nerve regeneration

Design and synthesis of elastin-like polypeptides for an ideal nerve conduit in peripheral nerve regeneration

Energy Technology Data Exchange (ETDEWEB)

Hsueh, Yu-Sheng [Institute of Biomedical Engineering, College of Engineering, National Taiwan University, Taipei 100, Taiwan (China); Institute of Biomedical Engineering, College of Medicine, National Taiwan University, Taipei 100, Taiwan (China); Savitha, S. [Institute of Biomedical Engineering, College of Engineering, National Taiwan University, Taipei 100, Taiwan (China); Department of Biotechnology, Sree Sastha Institute of Engineering and Technology, Chennai (India); Institute of Biomedical Engineering, College of Medicine, National Taiwan University, Taipei 100, Taiwan (China); Sadhasivam, S. [Division of Biomedical Engineering and Nanomedicine Research, National Health Research Institutes, Miaoli 350, Taiwan (China); Lin, Feng-Huei, E-mail: double@ntu.edu.tw [Institute of Biomedical Engineering, College of Engineering, National Taiwan University, Taipei 100, Taiwan (China); Division of Biomedical Engineering and Nanomedicine Research, National Health Research Institutes, Miaoli 350, Taiwan (China); Institute of Biomedical Engineering, College of Medicine, National Taiwan University, Taipei 100, Taiwan (China); Shieh, Ming-Jium [Institute of Biomedical Engineering, College of Engineering, National Taiwan University, Taipei 100, Taiwan (China); College of Medicine, National Taiwan University Hospital, Taipei 100, Taiwan (China); Institute of Biomedical Engineering, College of Medicine, National Taiwan University, Taipei 100, Taiwan (China)

2014-05-01

The study involves design and synthesis of three different elastin like polypeptide (ELP) gene monomers namely ELP1, ELP2 and ELP3 that encode for ELP proteins. The formed ELPs were assessed as an ideal nerve conduit for peripheral nerve regeneration. ELP1 was constructed with a small elongated pentapeptide carrying VPGVG sequence to mimic the natural polypeptide ELP. The ELP2 was designed by the incorporation of 4-penta peptide chains to improve the biocompatibility and mechanical strength. Thus, the third position in unique VPGVG was replaced with alanine to VPAVG and in a similar way modified to VPGKG, VPGEG and VPGIG with the substitution of lysine, glutamic acid and isoleucine. In ELP3, fibronectin C5 domain endowed with REDV sequence was introduced to improve the cell attachment. The ELP1, ELP2 and ELP3 proteins expressed by Escherichia coli were purified by inverse transition cycling (ITC). The purified ELPs were confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting. The Schwann cell (SC) morphology and cell adhesion were assessed by fabrication of ELP membrane cross-linked with glutaraledhyde. The Schwann cell proliferation was measured by WST-1 assay. Immunofluorostaining of Schwann cells was accomplished with SC specific phenotypic marker, S100. - Highlights: • Design and synthesis of three gene monomers of elastin like polypeptides (ELP1, 2 and 3) were reported. • Molecular weight of ITC purified ELP1, ELP2 and ELP3 was in the range of 37–38 kDa. • Schwann cell adhesion was found to be prominent in ELP3 and could be used as nerve conduit for peripheral nerve regeneration.

Vasoactive intestinal polypeptide (VIP) in cirrhosis: arteriovenous extraction in different vascular beds

DEFF Research Database (Denmark)

Henriksen, Jens Henrik Sahl; Staun-Olsen, P; Fahrenkrug, J

1980-01-01

The concentration of vasoactive intestinal polypeptide (VIP) was determined in peripheral venous plasma from 136 patients with liver cirrhosis without gastrointestinal bleeding or coma and from 112 controls. In eight patients (cirrhosis, six; fibrosis, one; steatosis, one) arteriovenous extraction...... is significantly elevated in peripheral plasma from patients with cirrhosis, probably due to porto-systemic shunting and/or compromised hepatic elimination. Hepatic elimination is still likely to account for the inactivation of most of the VIP escaping from the neurosynapses throughout the body in patients...

Antitumor activity of newly synthesized oxo and ethylidene derivatives of bile acids and their amides and oxazolines.

Science.gov (United States)

Bjedov, Srđan; Jakimov, Dimitar; Pilipović, Ana; Poša, Mihalj; Sakač, Marija

2017-04-01

Bile acid derivatives with modifications in side chain and modifications on steroid skeleton were synthetized and their antitumor activity against five human cancer cell lines was investigated. Modifications in side chain include amid group, formed in reaction with 2-amino-2-methylpropanol, and 4,4-dimethyloxazoline group, obtained after cyclization of amides. In the steroid skeleton oxo groups were introduced in position 7 (2, 2a, 2b) and 7,12 (3, 3a, 3b). Ethylidene groups were introduced regio- and stereoselectively on C-7, and/or without stereoselectivity on C-3 by Wittig reaction. By combination of these modifications, a series of 19 bile acid derivatives were synthesized. Compounds containing both C-7 ethylidene and C-12 carbonyl groups (6, 6a, 6b) shown very good antitumor activity with IC 50 amide or oxazoline group has positive effect on cytotoxicity. Different molecular descriptors were determined in silico and after principal component analysis was found that molecular descriptor BLTF96 can be used for fast assessment of experimental cytotoxicity of bile acid derivatives. Copyright © 2017 Elsevier Inc. All rights reserved.

Conformational energy calculations on polypeptides and proteins: use of a statistical mechanical procedure for evaluating structure and properties.

Science.gov (United States)

Scheraga, H A; Paine, G H

1986-01-01

We are using a variety of theoretical and computational techniques to study protein structure, protein folding, and higher-order structures. Our earlier work involved treatments of liquid water and aqueous solutions of nonpolar and polar solutes, computations of the stabilities of the fundamental structures of proteins and their packing arrangements, conformations of small cyclic and open-chain peptides, structures of fibrous proteins (collagen), structures of homologous globular proteins, introduction of special procedures as constraints during energy minimization of globular proteins, and structures of enzyme-substrate complexes. Recently, we presented a new methodology for predicting polypeptide structure (described here); the method is based on the calculation of the probable and average conformation of a polypeptide chain by the application of equilibrium statistical mechanics in conjunction with an adaptive, importance sampling Monte Carlo algorithm. As a test, it was applied to Met-enkephalin.

Newly Homeless Youth Typically Return Home

OpenAIRE

Milburn, Norweeta G.; Rosenthal, Doreen; Rotheram-Borus, Mary Jane; Mallett, Shelley; Batterham, Philip; Rice, Eric; Solorio, Rosa

2007-01-01

165 newly homeless adolescents from Melbourne, Australia and 261 from Los Angeles, United States were surveyed and followed for two years. Most newly homeless adolescents returned home (70% U.S., 47% Australia) for significant amounts of time (39% U.S., 17% Australia more than 12 months) within two years of becoming homeless.

tRNA-mediated labelling of proteins with biotin. A nonradioactive method for the detection of cell-free translation products.

Science.gov (United States)

Kurzchalia, T V; Wiedmann, M; Breter, H; Zimmermann, W; Bauschke, E; Rapoport, T A

1988-03-15

We have developed a new method for the rapid and sensitive detection of cell-free translation products. Biotinylated lysine is incorporated into newly synthesized proteins by means of lysyl-tRNA that is modified in the epsilon-position. After electrophoresis in a dodecyl sulfate gel and blotting onto nitrocellulose, the translation products can be identified by probing with streptavidin and biotinylated alkaline phosphatase, followed by incubation with a chromogenic enzyme substrate. The non-radioactive labelling by biotin approaches in its sensitivity that obtained by radioactive amino acids. The products are absolutely stable and can be rapidly identified. The new method has been tested with different mRNAs in the cell-free translation systems of wheat germ and reticulocytes. Neither the interaction of secretory proteins with the signal recognition particle nor the in vitro translocation across the endoplasmic reticulum membrane or core glycosylation of nascent polypeptides are prevented by the incorporation of biotinylated lysine residues. The results indicate that both the ribosome and the endoplasmic reticulum membrane permit the passage of polypeptides carrying bulky groups attached to the amino acids (by atomic models it was estimated that the size of the side chain of lysine changes from approximately equal to 0.8 nm to approximately equal to 2 nm after modification.

Impaired pancreatic polypeptide response to a meal in type 1 diabetic patients

DEFF Research Database (Denmark)

Rasmussen, M H; Carstensen, H; List, S

1993-01-01

The pancreatic polypeptide (PP) response to a mixed meal was investigated in seven insulin-dependent diabetics without measurable signs of diabetic autonomic neuropathy, and in seven healthy subjects. Since acute changes in metabolic regulation might influence the meal-induced PP response...... is independent of short-term changes in metabolic control. Since the response was attenuated in the insulin-dependent diabetic patients, who had no otherwise measurable signs of neuropathy, the PP response to a meal could be a sensitive indicator of dysfunction of the reflex arc controlling PP secretion...

A rat osteogenic cell line (UMR 106-01) synthesizes a highly sulfated form of bone sialoprotein.

Science.gov (United States)

Midura, R J; McQuillan, D J; Benham, K J; Fisher, L W; Hascall, V C

1990-03-25

The rat osteosarcoma cell line (UMR 106-01) synthesizes and secretes relatively large amounts of a sulfated glycoprotein into its culture medium (approximately 240 ng/10(6) cells/day). This glycoprotein was purified, and amino-terminal sequence analysis identified it as bone sialoprotein (BSP). [35S]Sulfate, [3H]glucosamine, and [3H]tyrosine were used as metabolic precursors to label the BSP. Sulfate esters were found on N- and O-linked oligosaccharides and on tyrosine residues, with about half of the total tyrosines in the BSP being sulfated. The proportion of 35S activity in tyrosine-O-sulfate (approximately 70%) was greater than that in N-linked (approximately 20%) and O-linked (approximately 10%) oligosaccharides. From the deduced amino acid sequence for rat BSP (Oldberg, A., Franzén, A., and Heinegård, D. (1988) J. Biol. Chem. 263, 19430-19432), the results indicate that on average approximately 12 tyrosine residues, approximately 3 N-linked, and approximately 2 O-linked oligosaccharides are sulfated/molecule. The carboxyl-terminal quarter of the BSP probably contains most, if not all, of the sulfated tyrosine residues because this region of the polypeptide contains the necessary requirements for tyrosine sulfation. Oligosaccharide analyses indicated that for every N-linked oligosaccharide on the BSP, there are also approximately 2 hexa-, approximately 5 tetra-, and approximately 2 trisaccharides O-linked to serine and threonine residues. On average, the BSP synthesized by UMR 106-01 cells would contain a total of approximately 3 N-linked and approximately 25 of the above O-linked oligosaccharides. This large number of oligosaccharides is in agreement with the known carbohydrate content (approximately 50%) of the BSP.

Effects of two newly synthesized analogues of lidocaine on rat arterial blood pressure and heart rate.

Science.gov (United States)

Al Rasheed, N M; Al Sayed, M I; Al Zuhair, H H; Al Obaid, A R; Fatani, A J

2001-04-01

Two new analogues of lidocaine were synthesized at the College of Pharmacy, King Saud University: compound I (Methyl-2-[2-(N,N-diethylamino) acetamido]-3-cyano-4,5-dimethylbenzoate) and compound II (Methyl-2-[2-(piperidino) acetamido]-3-cyano-4,5-dimethylbenzoate). Their influence on the arterial blood pressure and the heart rate of urethane-anaesthetized rats was studied and compared with the actions of lidocaine. Compounds I, II and lidocaine induced significant dose-dependent decreases in the arterial blood pressure and heart rate, which usually returned to basal values within 3-5 min. There were significant differences in the potency of the three compounds in producing their effects on blood pressure and heart rate (Plidocaine and compound I, respectively. The results of this study also indicated the ineffectiveness of antagonists of autonomic, histaminergic and 5-HT receptor, and various vasodilators in blocking the actions of the three compounds on blood pressure and heart rate. Pretreatment with CaCl(2)significantly reduced the hypotension and bradycardia induced by the three compounds, suggesting the involvement of calcium channels, probably of the L type. Several possible mechanisms are postulated. In conclusion, the results direct attention to the capability of the two new compounds to decrease blood pressure and heart rate; affects that may have clinical potential. Copyright 2001 Academic Press.

The lectin domain of UDP-N-acetyl-D-galactosamine: polypeptide N-acetylgalactosaminyltransferase-T4 directs its glycopeptide specificities

DEFF Research Database (Denmark)

Hassan, H; Reis, C A; Bennett, E P

2000-01-01

The initiation step of mucin-type O-glycosylation is controlled by a large family of homologous UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (GalNAc-transferases). Differences in kinetic properties, substrate specificities, and expression patterns of these isoenzymes provide for diff...

Forms of Knowledge Incorporated in Clinical Decision-making among Newly-Graduated Nurses: A Metasynthesis

DEFF Research Database (Denmark)

Voldbjerg, Siri; Elgaard Sørensen, Erik; Grønkjær, Mette

2014-01-01

Clinical-decision-making is of decisive importance to how evidence-based practice is put into practice. Schools of Nursing have a responsibility to teach and train nursing students to make clinical decisions within a frame of evidence-based practice. Clinical decision-making among nurses has been...... explored from numerous angles using a diversity of methodologies. Existing research has mainly focused on promoting and inhibiting factors for implementation of evidence-based practice and incorporation of research evidence in the clinical-decision. Little attention has been given to the nurses' behavior......, including the knowledge that actually informs the newly graduated nurses’ clinical decision. The aim of the study is to combine and synthesize results from qualitative research. Noblit and Hare’s meta-ethnographic approach is used to conduct a metasynthesis of qualitative research that has studied...

Binding Properties of Streptococcus gordonii SspA and SspB (Antigen I/II Family) Polypeptides Expressed on the Cell Surface of Lactococcus lactis MG1363

OpenAIRE

Holmes, Ann R.; Gilbert, Christophe; Wells, Jeremy M.; Jenkinson, Howard F.

1998-01-01

The oral bacterium Streptococcus gordonii expresses two cell wall-associated polypeptides, designated SspA (1,542 amino acid residues) and SspB (1,462 amino acid residues), that have 70% sequence identity. These polypeptides are members of the antigen I/II family of oral streptococcal adhesins and mediate the binding of streptococci to salivary glycoproteins, collagen, and other oral microorganisms such as Actinomyces naeslundii. To determine if SspA and SspB have differential binding propert...

Rapid measurement of 3J(H N-H alpha) and 3J(N-H beta) coupling constants in polypeptides.

Science.gov (United States)

Barnwal, Ravi Pratap; Rout, Ashok K; Chary, Kandala V R; Atreya, Hanudatta S

2007-12-01

We present two NMR experiments, (3,2)D HNHA and (3,2)D HNHB, for rapid and accurate measurement of 3J(H N-H alpha) and 3J(N-H beta) coupling constants in polypeptides based on the principle of G-matrix Fourier transform NMR spectroscopy and quantitative J-correlation. These experiments, which facilitate fast acquisition of three-dimensional data with high spectral/digital resolution and chemical shift dispersion, will provide renewed opportunities to utilize them for sequence specific resonance assignments, estimation/characterization of secondary structure with/without prior knowledge of resonance assignments, stereospecific assignment of prochiral groups and 3D structure determination, refinement and validation. Taken together, these experiments have a wide range of applications from structural genomics projects to studying structure and folding in polypeptides.

Histological evaluation of tissue reactions to newly synthetized calcium silicate- and hydroxyapatite-based bioactive materials: in vivo study

Directory of Open Access Journals (Sweden)

Opačić-Galić Vanja

2017-01-01

Full Text Available Introduction/Objective. Development of materials which could be used as biological bone substitutes is one of the most valuable and active fields of biomaterial research. The goal of the study was to research the reaction of tissue on calcium silicate- (CS and hydroxyapatitebased (CS-HA newly synthesized nanomaterials, after being implanted into the subcutaneous tissue of a rats and direct pulp capping of rabbit teeth. Methods. The tested materials were implanted in 40 Wistar male rats, sacrificed after seven, 15, 30, and 60 days. The direct pulp capping was performed on the teeth of rabbits. Cavities were prepared on the vestibular surface of the incisors. The animals were sacrificed after 10 and 15 days. The control material was mineral trioxide aggregate (MTA. Histological analysis covered the tracking of inflammatory reaction cellular components, presence of gigantic cells, and necrosis of the tissue. Results. Seven days after the implantation, the strongest inflammatory response was given by the MTA (3.3 Ѓ} 0.48, while CS and CS-HA scored 3 ± 0.71. After 60 days, the rate of inflammatory reactions dropped, which was the least visible with CS-HA (0.2 ± 0.45. The least visible inflammatory reaction of the rabbits’ pulp tissue was spotted with the CS (1.83 ± 0.75, than with the MTA and CS-HA (2.67 ± 1.53, 3 ± 0.63. Conclusion. The newly synthesized materials caused a slight reaction of the subcutaneous tissue. CS-HA showed the best tissue tolerance. Nanostructural biomaterials caused a slight to moderate inflammatory reaction of the rabbits’ pulp tissue only in the immediate vicinity of the implanted material.

Bisphenol A accelerates toxic amyloid formation of human islet amyloid polypeptide: a possible link between bisphenol A exposure and type 2 diabetes.

Directory of Open Access Journals (Sweden)

Hao Gong

Full Text Available Bisphenol A (BPA is a chemical compound widely used in manufacturing plastic products. Recent epidemiological studies suggest BPA exposure is positively associated with the incidence of type 2 diabetes mellitus (T2DM, however the mechanisms underlying this link remain unclear. Human islet amyloid polypeptide (hIAPP is a hormone synthesized and secreted by the pancreatic β-cells. Misfolding of hIAPP into toxic oligomers and mature fibrils can disrupt cell membrane and lead to β-cell death, which is regarded as one of the causative factors of T2DM. To test whether there are any connections between BPA exposure and hIAPP misfolding, we investigated the effects of BPA on hIAPP aggregation using thioflavin-T based fluorescence, transmission electronic microscopy, circular dichroism, dynamic light scattering, size-exclusion chromatography, fluorescence-dye leakage assay in an artificial micelle system and the generation of reactive oxygen species in INS-1 cells. We demonstrated that BPA not only dose-dependently promotes the aggregation of hIAPP and enhances the membrane disruption effects of hIAPP, but also promotes the extent of hIAPP aggregation related oxidative stress. Taken together, our results suggest that BPA exposure increased T2DM risk may involve the exacerbated toxic aggregation of hIAPP.

HPLC of the Polypeptides in a Hydrolyzate of Egg-White Lysozyme. An Experiment for the Undergraduate Biochemistry Laboratory.

Science.gov (United States)

Richardson, W. S., III; Burns, L.

1988-01-01

Describes a simple high-performance liquid chromatography experiment for undergraduate biochemistry laboratories. The experiment illustrates the separation of polypeptides by a step gradient elution using a single pump instrument with no gradient attachments. Discusses instrumentation, analysis, a sample preparation, and results. (CW)

A radioimmunoassay of gastric inhibitory polypeptide in human plasma

International Nuclear Information System (INIS)

Sarson, D.L.; Bryant, M.G.; Bloom, S.R.

1980-01-01

A sensitive radioimmunoassay for the measurement of human gastric inhibitory polypeptide (GIP), using pure porcine GIP, has been developed. Cross-reactivity of the antiserum with all available mammalian gut peptide preparations was negligible with the exception of glucagon when it was approximately 1%. Two major molecular forms of GIP were detectable in plasma and tissue extracts, one of large molecular size and the other corresponding to the elution coefficient of pure porcine standard. Concentrations of GIP in plasma from 50 normal subjects after overnight fasting were 9+-1.0(S.E.M.) pmol/1 rising to a peak of 34+-2.8 pmol/1 following the ingestion of a small mixed test meal. Ingestion of glucose or fat resulted in a similar rise of plasma GIP, whereas no change was observed after the ingestion of protein. (author)

Prevention of adsorption losses during radioimmunoassay of polypeptide hormones: effectiveness of albumins, gelatin, caseins, Tween 20 and plasma

International Nuclear Information System (INIS)

Livesey, J.H.; Donald, R.A.

1982-01-01

It is well known that polypeptide hormones adsorb to glass and plastic surfaces and that this adsorption may be reduced by adding a relatively large quantity of another protein. Consequently proteins (or sometimes detergents) are added almost universally to peptide hormone radioimmunassays to minimise loss of analyte by adsorption. This study was undertaken because there are few reports of the relative effectiveness of the proteins so used. The results suggest that moderate concentrations of the widely used albumins of Tween 20 do not always adequately prevent the adsorption of hormonal polypeptides to surfaces. Casein and alkali-treated casein appear to be more effective than the adsorption inhibitors in general use in radioimmunoassay for the range of hormones and adsorptive surfaces tested. They were also found to be very effective for preventing the adsorption of radio-labelled human luteinizing hormone, human growth hormone and Tyr-somatostatin. (Auth.)

Islet amyloid polypeptide in the control of food intake : An experimental study in the rat

OpenAIRE

Arnelo, Urban

1997-01-01

Control of food intake and satiety are physiologically complex processes, thatonly partly are understood. Several hormonal peptides have been proposed to mediatesatiety. Islet amyloid polypeptide (IAPP) is a recently discovered 37 amino acidpeptide, mainly produced by the pancreatic ß-cells. Initially, IAPP was shownto impair glucose tolerance at supra-physiological plasma concentrations and wasspeculated to be involved in the development of type-2 diabetes. More recent stud...

Immunoparesis in newly diagnosed Multiple Myeloma patients

DEFF Research Database (Denmark)

Sorrig, Rasmus; Klausen, Tobias W.; Salomo, Morten

2017-01-01

Immunoparesis (hypogammaglobulinemia) is associated to an unfavorable prognosis in newly diagnosed Multiple myeloma (MM) patients. However, this finding has not been validated in an unselected population-based cohort. We analyzed 2558 newly diagnosed MM patients in the Danish Multiple Myeloma...

An eco-friendly method of synthesizing gold nanoparticles using an otherwise worthless weed pistia (Pistia stratiotes L.).

Science.gov (United States)

Anuradha, J; Abbasi, Tasneem; Abbasi, S A

2015-09-01

A biomimetic method of gold nanoparticles synthesis utilizing the highly invasive aquatic weed pistia (Pistia stratiotes) is presented. In an attempt to utilize the entire plant, the efficacy of the extracts of all its parts - aerial and submerged - was explored with different proportions of gold (III) solution in generating gold nanoparticles (GNPs). The progress of the synthesis, which occurred at ambient temperature and pressure and commenced soon after mixing the pistia extracts and gold (III) solutions, was tracked using UV-visible spectrophotometry. The electron micrographs of the synthesized GNPs revealed that, depending on the metal-extract concentrations used in the synthesis, GNPs of either monodispersed spherical shape were formed or there was anisotropy resulting in a mixture of triangular, hexagonal, pentagonal, and truncated triangular shaped GNPs. This phenomenon was witnessed with the extracts of aerial parts as well as submerged parts of pistia. The presence of gold atoms in the nanoparticles was confirmed from the EDAX and X-ray diffraction studies. The FT-IR spectral study indicated that the primary and secondary amines associated with the polypeptide biomolecules could have been responsible for the reduction of the gold (III) ions to GNPs and their subsequent stabilization.

Glucose-dependent insulinotropic polypeptide may enhance fatty acid re-esterification in subcutaneous abdominal adipose tissue in lean humans

DEFF Research Database (Denmark)

Asmar, Meena; Simonsen, Lene; Madsbad, Sten

2010-01-01

Glucose-dependent insulinotropic polypeptide (GIP) has been implicated in lipid metabolism in animals. In humans, however, there is no clear evidence of GIP effecting lipid metabolism. The present experiments were performed in order to elucidate the effects of GIP on regional adipose tissue metab...

Peptides having reduced toxicity that stimulate cholesterol efflux

Energy Technology Data Exchange (ETDEWEB)

Bielicki, John K.; Johansson, Jan; Danho, Waleed

2016-08-16

The present invention provides a family of non-naturally occurring polypeptides having cholesterol efflux activity that parallels that of full-length apolipoproteins (e.g., Apo AI and Apo E), and having high selectivity for ABCA1 that parallels that of full-length apolipoproteins. Further, the peptides of the invention have little or no toxicity when administered at therapeutic and higher doses. The invention also provides compositions comprising such polypeptides, methods of identifying, screening and synthesizing such polypeptides, and methods of treating, preventing or diagnosing diseases and disorders associated with dyslipidemia, hypercholesterolemia and inflammation.

Tissue polypeptide-specific antigen (TPS) determinations before and during intermittent maximal androgen blockade in patients with metastatic prostatic carcinoma

NARCIS (Netherlands)

Kil, P. J. M.; Goldschmidt, H. M. J.; Wieggers, B. J. A.; Kariakine, O. B.; Studer, U. E.; Whelan, P.; Hetherington, J.; de Reijke, Th M.; Hoekstra, J. W.; Collette, L.

2003-01-01

To evaluate the prognostic significance of serially measured tissue polypeptide-specific antigen (TPS) levels in patients with metastatic prostatic carcinoma treated with intermittent maximal androgen blockade (MAB). To determine its value with respect to predicting response to treatment and time to

Generational differences among newly licensed registered nurses.

Science.gov (United States)

Keepnews, David M; Brewer, Carol S; Kovner, Christine T; Shin, Juh Hyun

2010-01-01

Responses of 2369 newly licensed registered nurses from 3 generational cohorts-Baby Boomers, Generation X, and Generation Y-were studied to identify differences in their characteristics, work-related experiences, and attitudes. These responses revealed significant differences among generations in: job satisfaction, organizational commitment, work motivation, work-to-family conflict, family-to-work conflict, distributive justice, promotional opportunities, supervisory support, mentor support, procedural justice, and perceptions of local job opportunities. Health organizations and their leaders need to anticipate intergenerational differences among newly licensed nurses and should provide for supportive working environments that recognize those differences. Orientation and residency programs for newly licensed nurses should be tailored to the varying needs of different generations. Future research should focus on evaluating the effectiveness of orientation and residency programs with regard to different generations so that these programs can be tailored to meet the varying needs of newly licensed nurses at the start of their careers. Copyright 2010 Mosby, Inc. All rights reserved.

Proteins associated with adaptation of cultured tobacco cells to NaCl

International Nuclear Information System (INIS)

Singh, N.K.; Handa, A.K.; Hasegawa, P.M.; Bressan, R.A.

1985-01-01

Cultured tobacco cells (Nicotiana tabacum L. cv Wisconsin 38) adapted to grow in medium containing high levels of NaCl or polyethylene glycol (PEG) produce several new or enhanced polypeptide bands on sodium dodecyl sulfate-polyarylamide gel electrophoresis. The intensities of some of the polypeptide bands increase with increasing levels of NaCl adaptation, while the intensities of other polypeptide bands are reduced. Synthesis of 26-kilodalton polypeptide(s) occurs at two different periods during culture growth of NaCl adapted cells. Unadapted cells also incorporate 35 S into a 26-kilodalton polypeptide during the later stage of culture growth beginning at midlog phase. The 26-kilodalton polypeptides from adapted and unadapted cells have similar partial proteolysis peptide maps and are immunologically cross-reactive. During adaptation to NaCl, unadapted cells synthesize and accumulate a major 26-kilodalton polypeptide, and the beginning of synthesis corresponds to the period of osmotic adjustment and culture growth. From their results, the authors suggest an involvement of the 26-kilodalton polypeptide in the adaptation of cultured tobacco cells to NaCl and water stress. 38 references, 11 figures, 2 tables

Target organs for avian pancreatic polypeptide

International Nuclear Information System (INIS)

Kimmel, J.R.; Pollock, H.G.

1981-01-01

The problem of the physiological function of pancreatic polypeptide (PP) has been approached by attempting to identify target organs. Avian PP (aPP) labeled with 125I at either the C-terminus (aPP-C) or the N-terminus (aPP-N) was injected into fasted chickens and allowed to circulate for 3-120 min. At the end of the equilibration period, the anesthetized bird was perfused first with saline, then with Buoin's solution. Samples of fixed tissue from various organs were collected, weighed, and counted. Control experiments consisted of coinjection of unlabeled aPP to compete for receptors. The rate of disappearance of aPP-N from plasma was greater than that of aPP-C. Binding of aPP-N by spleen, duodenum, ileum, pancreas, and bone marrow was markedly reduced by coinjection of unlabeled aPP. A similar but less marked reduction in binding was found in liver and proventriculus. aPP-C gave less conclusive results. The maximal competitive effect of unlabeled PP could be achieved in most cases with 30 microgram unlabeled aPP. It is concluded that pancreas, duodenum, ileum, spleen, and bone marrow, and probably liver and proventriculus, are target organs for aPP in the chicken and that the C-terminal region of aPP is involved in receptor binding

The cellular transcription factor CREB corresponds to activating transcription factor 47 (ATF-47) and forms complexes with a group of polypeptides related to ATF-43.

Science.gov (United States)

Hurst, H C; Masson, N; Jones, N C; Lee, K A

1990-12-01

Promoter elements containing the sequence motif CGTCA are important for a variety of inducible responses at the transcriptional level. Multiple cellular factors specifically bind to these elements and are encoded by a multigene family. Among these factors, polypeptides termed activating transcription factor 43 (ATF-43) and ATF-47 have been purified from HeLa cells and a factor referred to as cyclic AMP response element-binding protein (CREB) has been isolated from PC12 cells and rat brain. We demonstrated that CREB and ATF-47 are identical and that CREB and ATF-43 form protein-protein complexes. We also found that the cis requirements for stable DNA binding by ATF-43 and CREB are different. Using antibodies to ATF-43 we have identified a group of polypeptides (ATF-43) in the size range from 40 to 43 kDa. ATF-43 polypeptides are related by their reactivity with anti-ATF-43, DNA-binding specificity, complex formation with CREB, heat stability, and phosphorylation by protein kinase A. Certain cell types vary in their ATF-43 complement, suggesting that CREB activity is modulated in a cell-type-specific manner through interaction with ATF-43. ATF-43 polypeptides do not appear simply to correspond to the gene products of the ATF multigene family, suggesting that the size of the ATF family at the protein level is even larger than predicted from cDNA-cloning studies.

OPTIMIZATION OF TRANSESTERIFICATION PARAMETERS FOR OPTIMAL BIODIESEL YIELD FROM CRUDE JATROPHA OIL USING A NEWLY SYNTHESIZED SEASHELL CATALYST

Directory of Open Access Journals (Sweden)

A. N. R. REDDY

2017-10-01

Full Text Available Heterogeneous catalysts are promising catalysts for optimal biodiesel yield from transesterification of vegetable oils. In this work calcium oxide (CaO heterogeneous catalyst was synthesized from Polymedosa erosa seashell. Calcination was carried out at 900ºC for 2h and characterized using Fourier transform infrared spectroscopy. Catalytic efficiency of CaO was testified in transesterification of crude Jatropha oil (CJO. A response surface methodology (RSM based on five-level-two-factor central composite design (CCD was employed to optimize two critical transesterification parameters catalyst concentration to pretreated CJO (0.01-0.03 w/w % and the reaction time (90 min - 150 min. A JB yield of 96.48% was estimated at 0.023 w/w% catalyst and 125.76 min reaction using response optimizer. The legitimacy of the predicted model was verified through the experiments. The validation experiments conformed a yield of JB 96.4%±0.01% as optimal at 0.023 w/w% catalyst to pretreated oil ratio and 126 min reaction time.

Effect of double-tailed surfactant architecture on the conformation, self-assembly, and processing in polypeptide-surfactant complexes.

Science.gov (United States)

Junnila, Susanna; Hanski, Sirkku; Oakley, Richard J; Nummelin, Sami; Ruokolainen, Janne; Faul, Charl F J; Ikkala, Olli

2009-10-12

This work describes the solid-state conformational and structural properties of self-assembled polypeptide-surfactant complexes with double-tailed surfactants. Poly(L-lysine) was complexed with three dialkyl esters of phosphoric acid (i.e., phosphodiester surfactants), where the surfactant tail branching and length was varied to tune the supramolecular architecture in a facile way. After complexation with the branched surfactant bis(2-ethylhexyl) phosphate in an aqueous solution, the polypeptide chains adopted an alpha-helical conformation. These rod-like helices self-assembled into cylindrical phases with the amorphous alkyl tails pointing outward. In complexes with dioctyl phosphate and didodecyl phosphate, which have two linear n-octyl or n-dodecyl tails, respectively, the polypeptide formed antiparallel beta-sheets separated by alkyl layers, resulting in well-ordered lamellar self-assemblies. By heating, it was possible to trigger a partial opening of the beta-sheets and disruption of the lamellar phase. After repeated heating/cooling, all of these complexes also showed a glass transition between 37 and 50 degrees C. Organic solvent treatment and plasticization by overstoichiometric amount of surfactant led to structure modification in poly(L-lysine)-dioctyl phosphate complexes, PLL(diC8)(x) (x = 1.0-3.0). Here, the alpha-helical PLL is surrounded by the surfactants and these bottle-brush-like chains self-assemble in a hexagonal cylindrical morphology. As x is increased, the materials are clearly plasticized and the degree of ordering is improved: The stiff alpha-helical backbones in a softened surfactant matrix give rise to thermotropic liquid-crystalline phases. The complexes were examined by Fourier transform infrared spectroscopy, small- and wide-angle X-ray scattering, transmission electron microscopy, differential scanning calorimetry, polarized optical microscopy, and circular dichroism.

Skin peptide tyrosine-tyrosine, a member of the pancreatic polypeptide family: isolation, structure, synthesis, and endocrine activity.

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Mor, A; Chartrel, N; Vaudry, H; Nicolas, P

1994-10-25

Pancreatic polypeptide, peptide tyrosine-tyrosine (PYY), and neuropeptide tyrosine (NPY), three members of a family of structurally related peptides, are mainly expressed in the endocrine pancreas, in endocrine cells of the gut, and in the brain, respectively. In the present study, we have isolated a peptide of the pancreatic polypeptide family from the skin of the South American arboreal frog Phyllomedusa bicolor. The primary structure of the peptide was established as Tyr-Pro-Pro-Lys-Pro-Glu-Ser-Pro-Gly-Glu10-Asp-Ala-Ser-Pro-Glu-Glu- Met-Asn- Lys-Tyr20-Leu-Thr-Ala-Leu-Arg-His-Tyr-Ile-Asn-Leu30-Val-Thr- Arg-Gln-Arg-Tyr-NH2 . This unusual peptide, named skin peptide tyrosine-tyrosine (SPYY), exhibits 94% similarity with PYY from the frog Rana ridibunda. A synthetic replicate of SPYY inhibits melanotropin release from perifused frog neurointermediate lobes in very much the same way as NPY. These results demonstrate the occurrence of a PYY-like peptide in frog skin. Our data also suggest the existence of a pituitary-skin regulatory loop in amphibians.

Transgenic rescue of adipocyte glucose-dependent insulinotropic polypeptide receptor expression restores high fat diet-induced body weight gain

DEFF Research Database (Denmark)

Ugleholdt, Randi; Pedersen, Jens; Bassi, Maria Rosaria

2011-01-01

that was similar between the groups. In contrast, glucose-dependent insulinotropic polypeptide-mediated insulin secretion does not seem to be important for regulation of body weight after high fat feeding. The study supports a role of the adipocyte GIPr in nutrient-dependent regulation of body weight and lean mass...

Primary structure of pancreatic polypeptide from four species of Perissodactyla (Przewalski's horse, zebra, rhino, tapir).

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Henry, J S; Lance, V A; Conlon, J M

1991-12-01

Pancreatic polypeptide (PP) has been purified from extracts of the pancreas of four species of odd-toed ungulates (Perissodactyla): Przewalski's horse, mountain zebra, white rhinoceros, and mountain tapir. The amino acid sequence of Przewalski's horse pancreatic polypeptide was established as Ala-Pro-Met-Glu-Pro-Val-Tyr-Pro-Gly-Asp10-Asn- Ala-Thr-Pro-Glu-Gln-Met-Ala-Gln-Tyr20-Ala-Ala-Glu-Leu-Arg-Arg-Tyr- Ile-Asn-Met30 - Leu-Thr-Arg-Pro-Arg-Tyr.NH2. Zebra PP was identical to Przewalski's horse PP, rhinoceros PP contained three substitutions relative to the horse (Ser for Ala1, Leu for Met3, and Glu for Gln16), and tapir PP contained one substitution relative to the horse (Leu for Met3). On the basis of morphological characteristics and the fossil record, the rhinocerotids are classified with the tapirids in the suborder Ceratomorpha, whereas the horse and zebra belong to a separate suborder, Hippomorpha. On the basis of structural similarity of the PP molecules, however, it would appear that the tapir is more closely related to the horse than to the rhinoceros. These observations provide a further example of the need for extreme caution when inferring taxonomic or phylogenetic relationships between species from the structures of homologous peptides.

Plasma low-molecular-weight proteome profiling identified neuropeptide-Y as a prostate cancer biomarker polypeptide.

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Ueda, Koji; Tatsuguchi, Ayako; Saichi, Naomi; Toyama, Atsuhiko; Tamura, Kenji; Furihata, Mutsuo; Takata, Ryo; Akamatsu, Shusuke; Igarashi, Masahiro; Nakayama, Masato; Sato, Taka-Aki; Ogawa, Osamu; Fujioka, Tomoaki; Shuin, Taro; Nakamura, Yusuke; Nakagawa, Hidewaki

2013-10-04

In prostate cancer diagnosis, PSA test has greatly contributed to the early detection of prostate cancer; however, expanding overdiagnosis and unnecessary biopsies have emerged as serious issues. To explore plasma biomarkers complementing the specificity of PSA test, we developed a unique proteomic technology QUEST-MS (Quick Enrichment of Small Targets for Mass Spectrometry). The QUEST-MS method based on 96-well formatted sequential reversed-phase chromatography allowing efficient enrichment of <20 kDa proteins quickly and reproducibly. Plasma from 24 healthy controls, 19 benign prostate hypertrophy patients, and 73 prostate cancer patients were purified with QUEST-MS and analyzed by LC/MS/MS. Among 153 057 nonredundant peptides, 189 peptides showed prostate cancer specific detection pattern, which included a neurotransmitter polypeptide neuropeptide-Y (NPY). We further validated the screening results by targeted multiple reaction monitoring technology using independent sample set (n = 110). The ROC curve analysis revealed that logistic regression-based combination of NPY, and PSA showed 81.5% sensitivity and 82.2% specificity for prostate cancer diagnosis. Thus QUEST-MS technology allowed comprehensive and high-throughput profiling of plasma polypeptides and had potential to effectively uncover very low abundant tumor-derived small molecules, such as neurotransmitters, peptide hormones, or cytokines.

De novo DESIGN AND SYNTHESIS OF AN ICE-BINDING, DENDRIMERIC, POLYPEPTIDE BASED ON INSECT ANTIFREEZE PROTEINS

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Ricardo Vera Bravo

2011-12-01

Full Text Available A new strategy is presented for the designand synthesis of peptides that exhibitice-binding and antifreeze activity. Apennant-type dendrimer polypeptidescaffold combining an α-helical backbonewith four short β-strand branches wassynthesized in solid phase using Fmocchemistry in a divergent approach. The51-residue dendrimer was characterizedby reverse phase high performance liquidchromatography, mass spectrometry andcircular dichroism. Each β-strand branchcontained three overlapping TXT aminoacid repeats, an ice-binding motif foundin the ice-binding face of the sprucebudworm (Choristoneura fumiferanaand beetle (Tenebrio molitor antifreezeproteins. Ice crystals in the presence ofthe polypeptide monomer displayed flat,hexagonal plate morphology, similar tothat produced by weakly active antifreezeproteins. An oxidized dimeric form of thedendrimer polypeptide also produced flathexagonal ice crystals and was capableof inhibiting ice crystal growth upontemperature reduction, a phenomenontermed thermal hysteresis, a definingproperty of antifreeze proteins. Linkageof the pennant-type dendrimer to a trifunctionalcascade-type polypeptideproduced a trimeric macromolecule thatgave flat hexagonal ice crystals withhigher thermal hysteresis activity thanthe dimer or monomer and an ice crystal burst pattern similar to that producedby samples containing insect antifreezeproteins. This macromolecule was alsocapable of inhibiting ice recrystallization.

Enamel formation in vitro in mouse molar explants exposed to amelogenin polypeptides ATMP and LRAP on enamel development.

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Ravindranath, Rajeswari M H; Devarajan, Asokan; Bringas, Pablo

2007-12-01

The enamel matrix contains amelogenin, leucine-rich amelogenin-polypeptide (LRAP), resulting from alternative splicing of the primary amelogenin-RNA transcript and tyrosine-rich amelogenin-polypeptide (TRAP), a proteolytic product of amelogenin. Presence of amelogenin-trityrosyl-motif peptide (ATMP) distinguishes TRAP from LRAP. The roles of these polypeptides in the formation of enamel remain to be elucidated. The mouse in vitro molar tooth-organ developed from bud stage (E16) was exposed to LRAP, ATMP, and mutated ATMP (T-ATMP, third proline replaced by threonine). The histology and morphometry of the explants on day-12 in culture was examined using Mallory's stain. Guanidine-HCl soluble protein concentrations of explants were compared. The enamel width and protein solubility indicate that the explant on day-12 is comparable to postnatal molar on day-3 in vivo. The enamel of both untreated explants as well as that in vivo is fuchinophilic (acid fuchsin, AF+). ATMP reduced the ameloblast-height, accumulated AF+ spherules at the apical end of ameloblasts, and disrupted enamel-dentin bonding. T-ATMP abrogated deposition of AF+ material on the aniline blue positive (AB+) enamel matrix. LRAP reduced ameloblast-height, increased the enamel-width without disruption (at 17.25 nmol) and increased the density of AF+ dentinal tubules. AF+ substance from the tubules is released onto the surface of the dentin. The Guanidine-HCl-soluble protein is elevated in ATMP-treated explants but decreased in LRAP-treated explants. Exogenous ATMP, T-ATMP and LRAP have divergent effects on developing enamel. Exogenous ATMP, but not LRAP, abrogates enamel-dentin bonding at 17.25 nmol. LRAP may play a role in the differentiation of ameloblasts, growth of enamel and formation of dentinal tubules.

A nontoxic polypeptide oligomer with a fungicide potency under agricultural conditions which is equal or greater than that of their chemical counterparts.

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Sara Monteiro

Full Text Available There are literally hundreds of polypeptides described in the literature which exhibit fungicide activity. Tens of them have had attempted protection by patent applications but none, as far as we are aware, have found application under real agricultural conditions. The reasons behind may be multiple where the sensitivity to the Sun UV radiation can come in first place. Here we describe a multifunctional glyco-oligomer with 210 kDa which is mainly composed by a 20 kDa polypeptide termed Blad that has been previously shown to be a stable intermediary product of β-conglutin catabolism. This oligomer accumulates exclusively in the cotyledons of Lupinus species, between days 4 and 12 after the onset of germination. Blad-oligomer reveals a plethora of biochemical properties, like lectin and catalytic activities, which are not unusual per si, but are remarkable when found to coexist in the same protein molecule. With this vast range of chemical characteristics, antifungal activity arises almost as a natural consequence. The biological significance and potential technological applications of Blad-oligomer as a plant fungicide to agriculture, its uniqueness stems from being of polypeptidic in nature, and with efficacies which are either equal or greater than the top fungicides currently in the market are addressed.

PULSE SYNTHESIZING GENERATOR

Science.gov (United States)

Kerns, Q.A.

1963-08-01

>An electronlc circuit for synthesizing electrical current pulses having very fast rise times includes several sinewave generators tuned to progressively higher harmonic frequencies with signal amplitudes and phases selectable according to the Fourier series of the waveform that is to be synthesized. Phase control is provided by periodically triggering the generators at precisely controlled times. The outputs of the generators are combined in a coaxial transmission line. Any frequency-dependent delays that occur in the transmission line can be readily compensated for so that the desired signal wave shape is obtained at the output of the line. (AEC)

Anti-inflammatory and antinociceptive evaluation of newly synthesized 4-(substituted ethanoyl amino-3-mercapto-5-(4-methoxy phenyl-1,2,4-triazoles

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Neeraj Upmanyu

2011-01-01

Full Text Available Introduction: 1,2,4-triazoles and its derivatives have been reported to possess anti-inflammatory, analgesic, antimicrobial, anticancer, antitumor, antitubercular, anticonvulsant, openers of Ca-activated potassium (Maxi-K channels, antiviral properties, hypoglycemic, anxiolytic and antidepressant activity. Therefore, 1,2,4-triazole seems to be an important pharmacophore. Materials and Methods: The synthesis of 4-(substituted ethanoyl amino-3-mercapto-5-(4-methoxy phenyl-1,2,4-triazoles (6a-o were prepared following six step starting 4-methoxy benzoic acid and using different secondary amines and were characterized with the help of FT-IR, 1 H, 13 C NMR, FAB Mass and nitrogen analysis. These synthesized compounds (6a-o were then evaluated for anti-inflammatory activity by carrageenan induced paw edema method.Out of these synthesized compounds, some (6f, i and k were evaluated for antinociceptive activity by Hot plate method and Tail immersion method. Results and Discussion: The synthesis of 4-(substituted amino-3-mercapto-5-(4-methoxy phenyl-1,2,4-triazoles (6a-o was accomplished. The IR spectra exhibited characteristic bands for C-N, C=N, SH and C=O at 1350-1360, 1511-1548, 2520-2594.3 and 1650-1719 cm -1 . The C-O-C asymmetric and symmetric str. was at 1250-1254 and 1027-1079.3 cm -1 respectively. In 1 H-NMR spectra, a singlet of CONH was found in the range of δ 9.92-10.18 ppm and another singlet of thiol group was observed in the range of δ 8.63-9.92 ppm. A singlet of Ar-OCH 3 was also found between δ 3.57-3.91 ppm. In 13 C- NMR spectra, C-3 and C-5 of the 1,2,4 - triazole nucleus were observed in the range of δ 147-166.9 ppm. Carbonyl carbon and methylene carbon of -NHCOCH 2 N< were found between δ 166.5-177.5 and δ 47.1-62 ppm respectively. Acute toxicity study was donr following OECD-423 and cut-off dose was found to be between 1000-1500 mg/kg body weight. At the dose level of 100 mg/kg, 6f, 6i and 6k exhibited appreciable inhibition

INTERACTION BETWEEN DIFFERENT MOLECULAR FORMS OF IMMUNOGLOBULIN A AND RECOMBINANT DERIVATIVES POLYPEPTIDES OF BAC RECEPTOR PROTEINS FROM GROUP B STREPTOCOCCI

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A. S. Korzhueva

2008-01-01

Full Text Available Abstract. The article concerns interactions between immunoglobulin A and recombinant P6, P7, P8 polypeptides, designed on the basis of externally localized Bac protein of the Group B streptococci, possessing IgA-binding activity.There is a current demand for immunochemical reagents that are strictly specific for IgA, in order to develop antigenic standards for detection of IgA levels in biological fluids, as well as for affinity purification of IgA and its fragments.To analyze an opportunity of the abovementioned application ways for these proteins, a special study was performed to assay an interaction capability of recombinant P6, P7, P8 polypeptides binding to Fc regions of different IgA forms (serum IgA, secretory IgA, subclasses of serum IgA – IgA1, IgA2. Selectivity of ligand binding was specially confirmed.It was found out that, among three presented polypeptides, the structure of recombinant P6 derivative proved to be optimal for IgA-binding ability of Bac protein.Structural features of IgA-binding fragments of Bac protein, i.e., binding site position on the IgA molecule (proximity to epitopes for three monoclonal antibodies, variability of the site structure, as well as resistance of binding site for P6, P7, P8 in IgA molecule against partial disulfide bonds reduction. (Med. Immunol., vol. 10, N 4-5, pp 327-336.

Establishment probability in newly founded populations

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Gusset Markus

2012-06-01

Full Text Available Abstract Background Establishment success in newly founded populations relies on reaching the established phase, which is defined by characteristic fluctuations of the population’s state variables. Stochastic population models can be used to quantify the establishment probability of newly founded populations; however, so far no simple but robust method for doing so existed. To determine a critical initial number of individuals that need to be released to reach the established phase, we used a novel application of the “Wissel plot”, where –ln(1 – P0(t is plotted against time t. This plot is based on the equation P0t=1–c1e–ω1t, which relates the probability of extinction by time t, P0(t, to two constants: c1 describes the probability of a newly founded population to reach the established phase, whereas ω1 describes the population’s probability of extinction per short time interval once established. Results For illustration, we applied the method to a previously developed stochastic population model of the endangered African wild dog (Lycaon pictus. A newly founded population reaches the established phase if the intercept of the (extrapolated linear parts of the “Wissel plot” with the y-axis, which is –ln(c1, is negative. For wild dogs in our model, this is the case if a critical initial number of four packs, consisting of eight individuals each, are released. Conclusions The method we present to quantify the establishment probability of newly founded populations is generic and inferences thus are transferable to other systems across the field of conservation biology. In contrast to other methods, our approach disaggregates the components of a population’s viability by distinguishing establishment from persistence.

NMR experiments for resonance assignments of 13C, 15N doubly-labeled flexible polypeptides: Application to the human prion protein hPrP(23-230)

International Nuclear Information System (INIS)

Liu Aizhuo; Riek, Roland; Wider, Gerhard; Schroetter, Christine von; Zahn, Ralph; Wuethrich, Kurt

2000-01-01

A combination of three heteronuclear three-dimensional NMR experiments tailored for sequential resonance assignments in uniformly 15 N, 13 C-labeled flexible polypeptide chains is described. The 3D (H)N(CO-TOCSY)NH, 3D (H)CA(CO-TOCSY)NH and 3D (H)CBCA(CO-TOCSY)NH schemes make use of the favorable 15 N chemical shift dispersion in unfolded polypeptides, exploit the slow transverse 15 N relaxation rates of unfolded polypeptides in high resolution constant-time [ 1 H, 15 N]-correlation experiments, and use carbonyl carbon homonuclear isotropic mixing to transfer magnetization sequentially along the amino acid sequence. Practical applications are demonstrated with the 100-residue flexible tail of the recombinant human prion protein, making use of spectral resolution up to 0.6 Hz in the 15 N dimension, simultaneous correlation with the two adjacent amino acid residues to overcome problems associated with spectral overlap, and the potential of the presently described experiments to establish nearest-neighbor correlations across proline residues in the amino acid sequence

Elastin as a self-organizing biomaterial: use of recombinantly expressed human elastin polypeptides as a model for investigations of structure and self-assembly of elastin.

Science.gov (United States)

Keeley, Fred W; Bellingham, Catherine M; Woodhouse, Kimberley A

2002-02-28

Elastin is the major extracellular matrix protein of large arteries such as the aorta, imparting characteristics of extensibility and elastic recoil. Once laid down in tissues, polymeric elastin is not subject to turnover, but is able to sustain its mechanical resilience through thousands of millions of cycles of extension and recoil. Elastin consists of ca. 36 domains with alternating hydrophobic and cross-linking characteristics. It has been suggested that these hydrophobic domains, predominantly containing glycine, proline, leucine and valine, often occurring in tandemly repeated sequences, are responsible for the ability of elastin to align monomeric chains for covalent cross-linking. We have shown that small, recombinantly expressed polypeptides based on sequences of human elastin contain sufficient information to self-organize into fibrillar structures and promote the formation of lysine-derived cross-links. These cross-linked polypeptides can also be fabricated into membrane structures that have solubility and mechanical properties reminiscent of native insoluble elastin. Understanding the basis of the self-organizational ability of elastin-based polypeptides may provide important clues for the general design of self-assembling biomaterials.

Application of evolutionary algorithm methods to polypeptide folding: comparison with experimental results for unsolvated Ac-(Ala-Gly-Gly)5-LysH+

DEFF Research Database (Denmark)

Damsbo, Martin; Kinnear, Brian S; Hartings, Matthew R

2004-01-01

We present an evolutionary method for finding the low-energy conformations of polypeptides. The application, called FOLDAWAY,is based on a generic framework and uses several evolutionary operators as well as local optimization to navigate the complex energy landscape of polypeptides. It maintains...... mobility measurements. It has a flat energy landscape where helical and globular conformations have similar energies. FOLDAWAY locates several large groups of structures not found in previous molecular dynamics simulations for this peptide, including compact globular conformations, which are probably...... two complementary representations of the structures and uses the CHARMM force field for evaluating the energies. The method is applied to unsolvated Met-enkephalin and Ac-(Ala-Gly-Gly)(5)-Lys(+)H(+). Unsolvated Ac-(Ala-Gly-Gly)(5)-Lys(+)H(+) has been the object of recent experimental studies using ion...

Islet Amyloid Polypeptide: Structure, Function, and Pathophysiology

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Rehana Akter

2016-01-01

Full Text Available The hormone islet amyloid polypeptide (IAPP, or amylin plays a role in glucose homeostasis but aggregates to form islet amyloid in type-2 diabetes. Islet amyloid formation contributes to β-cell dysfunction and death in the disease and to the failure of islet transplants. Recent work suggests a role for IAPP aggregation in cardiovascular complications of type-2 diabetes and hints at a possible role in type-1 diabetes. The mechanisms of IAPP amyloid formation in vivo or in vitro are not understood and the mechanisms of IAPP induced β-cell death are not fully defined. Activation of the inflammasome, defects in autophagy, ER stress, generation of reactive oxygen species, membrane disruption, and receptor mediated mechanisms have all been proposed to play a role. Open questions in the field include the relative importance of the various mechanisms of β-cell death, the relevance of reductionist biophysical studies to the situation in vivo, the molecular mechanism of amyloid formation in vitro and in vivo, the factors which trigger amyloid formation in type-2 diabetes, the potential role of IAPP in type-1 diabetes, the development of clinically relevant inhibitors of islet amyloidosis toxicity, and the design of soluble, bioactive variants of IAPP for use as adjuncts to insulin therapy.

Toughening of Thermoresponsive Arrested Networks of Elastin-Like Polypeptides To Engineer Cytocompatible Tissue Scaffolds.

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Glassman, Matthew J; Avery, Reginald K; Khademhosseini, Ali; Olsen, Bradley D

2016-02-08

Formulation of tissue engineering or regenerative scaffolds from simple bioactive polymers with tunable structure and mechanics is crucial for the regeneration of complex tissues, and hydrogels from recombinant proteins, such as elastin-like polypeptides (ELPs), are promising platforms to support these applications. The arrested phase separation of ELPs has been shown to yield remarkably stiff, biocontinuous, nanostructured networks, but these gels are limited in applications by their relatively brittle nature. Here, a gel-forming ELP is chain-extended by telechelic oxidative coupling, forming extensible, tough hydrogels. Small angle scattering indicates that the chain-extended polypeptides form a fractal network of nanoscale aggregates over a broad concentration range, accessing moduli ranging from 5 kPa to over 1 MPa over a concentration range of 5-30 wt %. These networks exhibited excellent erosion resistance and allowed for the diffusion and release of encapsulated particles consistent with a bicontinuous, porous structure with a broad distribution of pore sizes. Biofunctionalized, toughened networks were found to maintain the viability of human mesenchymal stem cells (hMSCs) in 2D, demonstrating signs of osteogenesis even in cell media without osteogenic molecules. Furthermore, chondrocytes could be readily mixed into these gels via thermoresponsive assembly and remained viable in extended culture. These studies demonstrate the ability to engineer ELP-based arrested physical networks on the molecular level to form reinforced, cytocompatible hydrogel matrices, supporting the promise of these new materials as candidates for the engineering and regeneration of stiff tissues.

Glucose-dependent insulinotropic polypeptide (GIP) receptor deletion leads to reduced bone strength and quality.

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Mieczkowska, Aleksandra; Irwin, Nigel; Flatt, Peter R; Chappard, Daniel; Mabilleau, Guillaume

2013-10-01

Bone is permanently remodeled by a complex network of local, hormonal and neuronal factors that affect osteoclast and osteoblast biology. In this context, a role for gastro-intestinal hormones has been proposed based on evidence that bone resorption dramatically falls after a meal. Glucose-dependent insulinotropic polypeptide (GIP) is one of the candidate hormones as its receptor, glucose-dependent insulinotropic polypeptide receptor (GIPR), is expressed in bone. In the present study we investigated bone strength and quality by three-point bending, quantitative x-ray microradiography, microCT, qBEI and FTIR in a GIPR knockout (GIPR KO) mouse model and compared with control wild-type (WT) animals. Animals with a deletion of the GIPR presented with a significant reduction in ultimate load (--11%), stiffness (-16%), total absorbed (-28%) and post-yield energies (-27%) as compared with WT animals. Furthermore, despite no change in bone outer diameter, the bone marrow diameter was significantly increased and as a result cortical thickness was significantly decreased by 20% in GIPR deficient animals. Bone resorption at the endosteal surface was significantly increased whilst bone formation was unchanged in GIPR deficient animals. Deficient animals also presented with a pronounced reduction in the degree of mineralization of bone matrix. Furthermore, the amount of mature cross-links of collagen matrix was significantly reduced in GIPR deficient animals and was associated with lowered intrinsic material properties. Taken together, these data support a positive effect of the GIPR on bone strength and quality. © 2013.

LFG-500, a newly synthesized flavonoid, attenuates lipopolysaccharide-induced acute lung injury and inflammation in mice.

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Li, Chenglin; Yang, Dan; Cao, Xin; Wang, Fan; Jiang, Haijing; Guo, Hao; Du, Lei; Guo, Qinglong; Yin, Xiaoxing

2016-08-01

Acute lung injury (ALI) often causes significant morbidity and mortality worldwide. Improved treatment and effective strategies are still required for ALI patients. Our previous studies demonstrated that LFG-500, a novel synthesized flavonoid, has potent anti-cancer activities, while its anti-inflammatory effect has not been revealed. In the present study, the in vivo protective effect of LFG-500 on the amelioration of lipopolysaccharide (LPS)-induced ALI and inflammation was detected. LFG-500 attenuated LPS-induced histological alterations, suppressed the infiltration of inflammatory cells in lung tissues and bronchoalveolar lavage fluid, as well as inhibited the secretion of several inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6 in lung tissues after LPS challenge. In addition, the in vitro effects and mechanisms were studied in LPS stimulated RAW 264.7 cells and THP-1 cells. LFG-500 significantly decreased the secretion and expression of TNF-α, IL-1β, and IL-6 through inhibiting the transcriptional activation of NF-κB. Moreover, overexpression of NF-κB p65 reversed the inhibitory effect of LFG-500 on LPS-induced NF-κB activation and inflammatory cytokine secretion. Further elucidation of the mechanism revealed that p38 and JNK MAPK pathways were involved in the anti-inflammation effect of LFG-500, through which LFG-500 inhibited the classical IKK-dependent pathway and led to inactivation of NF-κB. More importantly, LFG-500 suppressed the expression and nuclear localization of NF-κB in LPS-induced ALI mice. Taken together, these results demonstrated that LFG-500 could attenuate LPS-induced ALI and inflammation by suppressing NF-κB activation, which provides new evidence for the anti-inflammation activity of LFG-500. Copyright © 2016 Elsevier Inc. All rights reserved.

Iodine and tritium labelling of curarizing and cardiotoxic agents. Study of the conformation of toxic polypeptides extracted from snake venom

International Nuclear Information System (INIS)

Menez, Andre.

1977-01-01

A short review of present-day knowledge on the action mechanism of toxic snake venom polypeptides is followed by a study of the radioactive labelling of some toxic compounds. Those dealt with more especially are Naja nigricollis α toxin and Laticauda semifasciata b erabutoxin, then (+) tubocurarin, a non-peptidic curarizing alkaloid, and two cardiotoxic polypeptides: cytotoxin II and cardiotoxin γ extracted from the venom of Naja naja and Naja nigricollis respectively. The labelling principle is based on the specific fixation of one or more iodine atoms then tritium substitution of the halogen by catalytic hydrogenolysis. As predicted from titration of the aromatic groups the halogenation process, obtained by addition of iodine monochloride, takes place sometimes on the phenolic nuclei and sometimes on the imidazole nuclei, the position of which targets within each sequence has been identified. From results of the study of reactivity towards iodine combined with those of basic titration, the accessibility of several aromatic nuclei has also been defined. Each iodinated polypeptide is then hydrogenolysed in the presence of tritium gas giving a specific activity between 4 and 27 Ci/mmole according to the compound treated. In all cases the biological potential and physical properties of the radioactive material obtained by the above titration process remained intact. An example of the bonding kinetics of short toxins with the partially purified choligenic receptor is given in the special case of tritiated b erabutoxin. The affinity of this toxin for its receptor target is strong, though slightly less so than that of tritiated Naja nigricollis α toxin [fr

Expression and purification of short hydrophobic elastin-like polypeptides with maltose-binding protein as a solubility tag.

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Bataille, Laure; Dieryck, Wilfrid; Hocquellet, Agnès; Cabanne, Charlotte; Bathany, Katell; Lecommandoux, Sébastien; Garbay, Bertrand; Garanger, Elisabeth

2015-06-01

Elastin-like polypeptides (ELPs) are biodegradable polymers with interesting physico-chemical properties for biomedical and biotechnological applications. The recombinant expression of hydrophobic elastin-like polypeptides is often difficult because they possess low transition temperatures, and therefore form aggregates at sub-ambient temperatures. To circumvent this difficulty, we expressed in Escherichia coli three hydrophobic ELPs (VPGIG)n with variable lengths (n=20, 40, and 60) in fusion with the maltose-binding protein (MBP). Fusion proteins were soluble and yields of purified MBP-ELP ranged between 66 and 127mg/L culture. After digestion of the fusion proteins by enterokinase, the ELP moiety was purified by using inverse transition cycling. The purified fraction containing ELP40 was slightly contaminated by traces of undigested fusion protein. Purification of ELP60 was impaired because of co-purification of the MBP tag during inverse transition cycling. ELP20 was successfully purified to homogeneity, as assessed by gel electrophoresis and mass spectrometry analyses. The transition temperature of ELP20 was measured at 15.4°C in low salt buffer. In conclusion, this method can be used to produce hydrophobic ELP of low molecular mass. Copyright © 2015 Elsevier Inc. All rights reserved.

A newly developed Fe-doped calcium sulfide nanoparticles with magnetic property for cancer hyperthermia

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Wu, Steven Yueh-Hsiu; Tseng, Ching-Li; Lin, Feng-Huei

2010-05-01

In this study, a magnetic iron-doped calcium sulfide (Fe-CaS) nanoparticle was newly developed and studied for the purpose of hyperthermia due to its promising magnetic property, adequate biodegradation rate, and relatively good biocompatibility. Fe-CaS nanoparticles were synthesized by a wet chemical co-precipitation process with heat treatment in a N2 atmosphere, and were subsequently cooled in N2 and exposed to air at a low temperature. The crystal structure of the Fe-CaS nanoparticles was similar to that of the CaS, which was identified by an X-ray diffractometer (XRD). The particle size was less than 40 nm based on a Debye-Scherrer equation and transmission electron microscope (TEM) examination. Magnetic properties obtained from the SQUID magnetometer demonstrated that the synthesized CaS was a diamagnetic property. Once the Fe ions were doped, the synthesized Fe-CaS converted into paramagnetism which showed no hysteresis loop. Having been heated above 600 °C in N2, the Fe-CaS showed a promising magnetic property to produce enough energy to increase the temperature for hyperthermia. 10 mg/ml of the Fe-CaS was able to generate heat to elevate the media temperature over 42.5 °C within 6 min. The area of the hysteresis loop increased with the increasing of the treated temperature, especially at 800 °C for 1 h. This is because more Fe ions replaced Ca ions in the lattice at the higher heat treatment temperature. The heat production was also increasing with the increasing of heat treatment temperature, which resulted in an adequate specific absorption ratio (SAR) value, which was found to be 45.47 W/g at 37 °C under an alternative magnetic field of f = 750 KHz , H = 10 Oe. The in vitro biocompatibility test of the synthesized Fe-CaS nanoparticles examined by the LDH assay showed no cytotoxicity to 3T3 fibroblast. The result of in vitro cell hyperthermia shows that under magnetic field the Fe-CaS nanoparticles were able to generate heat and kill the CT-26 cancer

A newly developed Fe-doped calcium sulfide nanoparticles with magnetic property for cancer hyperthermia

International Nuclear Information System (INIS)

Wu, Steven Yueh-Hsiu; Tseng, Ching-Li; Lin, Feng-Huei

2010-01-01

In this study, a magnetic iron-doped calcium sulfide (Fe-CaS) nanoparticle was newly developed and studied for the purpose of hyperthermia due to its promising magnetic property, adequate biodegradation rate, and relatively good biocompatibility. Fe-CaS nanoparticles were synthesized by a wet chemical co-precipitation process with heat treatment in a N 2 atmosphere, and were subsequently cooled in N 2 and exposed to air at a low temperature. The crystal structure of the Fe-CaS nanoparticles was similar to that of the CaS, which was identified by an X-ray diffractometer (XRD). The particle size was less than 40 nm based on a Debye-Scherrer equation and transmission electron microscope (TEM) examination. Magnetic properties obtained from the SQUID magnetometer demonstrated that the synthesized CaS was a diamagnetic property. Once the Fe ions were doped, the synthesized Fe-CaS converted into paramagnetism which showed no hysteresis loop. Having been heated above 600 o C in N 2 , the Fe-CaS showed a promising magnetic property to produce enough energy to increase the temperature for hyperthermia. 10 mg/ml of the Fe-CaS was able to generate heat to elevate the media temperature over 42.5 o C within 6 min. The area of the hysteresis loop increased with the increasing of the treated temperature, especially at 800 o C for 1 h. This is because more Fe ions replaced Ca ions in the lattice at the higher heat treatment temperature. The heat production was also increasing with the increasing of heat treatment temperature, which resulted in an adequate specific absorption ratio (SAR) value, which was found to be 45.47 W/g at 37 o C under an alternative magnetic field of f = 750 KHz, H = 10 Oe. The in vitro biocompatibility test of the synthesized Fe-CaS nanoparticles examined by the LDH assay showed no cytotoxicity to 3T3 fibroblast. The result of in vitro cell hyperthermia shows that under magnetic field the Fe-CaS nanoparticles were able to generate heat and kill the CT-26

SM50 repeat-polypeptides self-assemble into discrete matrix subunits and promote appositional calcium carbonate crystal growth during sea urchin tooth biomineralization.

Science.gov (United States)

Mao, Yelin; Satchell, Paul G; Luan, Xianghong; Diekwisch, Thomas G H

2016-01-01

The two major proteins involved in vertebrate enamel formation and echinoderm sea urchin tooth biomineralization, amelogenin and SM50, are both characterized by elongated polyproline repeat domains in the center of the macromolecule. To determine the role of polyproline repeat polypeptides in basal deuterostome biomineralization, we have mapped the localization of SM50 as it relates to crystal growth, conducted self-assembly studies of SM50 repeat polypeptides, and examined their effect on calcium carbonate and apatite crystal growth. Electron micrographs of the growth zone of Strongylocentrotus purpuratus sea urchin teeth documented a series of successive events from intravesicular mineral nucleation to mineral deposition at the interface between tooth surface and odontoblast syncytium. Using immunohistochemistry, SM50 was detected within the cytoplasm of cells associated with the developing tooth mineral, at the mineral secreting front, and adjacent to initial mineral deposits, but not in muscles and ligaments. Polypeptides derived from the SM50 polyproline alternating hexa- and hepta-peptide repeat region (SM50P6P7) formed highly discrete, donut-shaped self-assembly patterns. In calcium carbonate crystal growth studies, SM50P6P7 repeat peptides triggered the growth of expansive networks of fused calcium carbonate crystals while in apatite growth studies, SM50P6P7 peptides facilitated the growth of needle-shaped and parallel arranged crystals resembling those found in developing vertebrate enamel. In comparison, SM50P6P7 surpassed the PXX24 polypeptide repeat region derived from the vertebrate enamel protein amelogenin in its ability to promote crystal nucleation and appositional crystal growth. Together, these studies establish the SM50P6P7 polyproline repeat region as a potent regulator in the protein-guided appositional crystal growth that occurs during continuous tooth mineralization and eruption. In addition, our studies highlight the role of species

Composites comprising biologically-synthesized nanomaterials

Science.gov (United States)

Curran, Seamus; Dias, Sampath; Blau, Werner; Wang, Jun; Oremland, Ronald S; Baesman, Shaun

2013-04-30

The present disclosure describes composite materials containing a polymer material and a nanoscale material dispersed in the polymer material. The nanoscale materials may be biologically synthesized, such as tellurium nanorods synthesized by Bacillus selenitireducens. Composite materials of the present disclosure may have optical limiting properties and find use in optical limiting devices.

Thermoluminescence properties of Li2B4O7:Cu, B phosphor synthesized using solution combustion technique

Science.gov (United States)

Ozdemir, A.; Altunal, V.; Kurt, K.; Depci, T.; Yu, Y.; Lawrence, Y.; Nur, N.; Guckan, V.; Yegingil, Z.

2017-12-01

To determine the effects of various concentrations of the activators copper (Cu) and boron (B) on the thermoluminescence (TL) properties of lithium tetraborate, the phosphor was first synthesized and doped with five different concentrations of copper (0.1-0.005 wt%) using solution combustion method. 0.01 wt% Cu was the concentration which showed the most significant increase in the sensitivity of the phosphor. The second sort of Li2B4O7:Cu material was prepared by adding B (0.001-0.03 wt%) to it. The newly developed copper-boron activated lithium tetraborate (Li2B4O7:Cu, B) material with 0.01 wt% Cu and 0.001 wt% B impurity concentrations was shown to have promise as a TL phosphor. The material formation was examined using powder x-Ray Diffraction (XRD) analysis and Scanning Electron Microscope (SEM) imaging. Fourier Transform Infrared (FT-IR) spectrum of the synthesized polycrystalline powder sample was also recorded. The TL glow curves were analyzed to determine various dosimetric characteristics of the synthesized luminophosphors. The dose response increased in a ;linear; way with the beta-ray exposure between 0.1-20 Gy, a dose range being interested in medical dosimetry. The response with changing photon and electron energy was studied. The rate of decay of the TL signal was investigated both for dark storage and under direct sunlight. Li2B4O7:Cu, B showed no individual variation of response in 9 recycling measurements. The fluorescence spectrum was determined. The kinetic parameters were estimated by different methods and the results discussed. The studied properties of synthesized Li2B4O7:Cu, B were found all favorable for dosimetric purposes.

Is pancreatic polypeptide response to food ingestion a reliable index of vagal function in type 1 diabetes?

DEFF Research Database (Denmark)

Damholt, M B; Arlien-Soeborg, P; Hilsted, L

2006-01-01

The diagnosis of autonomic neuropathy in diabetic patients is based on cardiovascular reflex tests. Since cardiac function may be affected by arteriosclerosis and cardiomyopathy in type 1 diabetes mellitus, alternative tests reflecting vagal nerve function, in other organ systems, are needed....... In this study the pancreatic polypeptide (PP) response to a mixed meal was evaluated in healthy subjects and in recently diagnosed type 1 diabetic patients....

Vasoactive intestinal polypeptide (VIP) tissue distribution in the rat as measured by radioimmunoassay and by radioreceptorassay

International Nuclear Information System (INIS)

Besson, J.; Dupont, C.; Laburthe, M.; Bataille, D.; Rosselin, G.

1977-01-01

A new radioimmunoassay which allows the measurement of the rat vasoactive intestinal polypeptide, was performed. VIP is present in the whole digestive tract of rat, mainly between the duodenum and the colon. 1.5% of the total VIP is present in brain. The VIP-like immunoreactivity appears to correspond to biologically active molecule since a radioreceptorassay using liver plasma membranes as the target tissue, gives the same results as the radioimmunoassay [fr

Heterogeneity of rabbit endogenous pyrogens is not attributable to glycosylated variants of a single polypeptide chain.

OpenAIRE

Murphy, P A; Cebula, T A; Windle, B E

1981-01-01

Rabbit endogenous pyrogens were of about the same molecular size, but showed considerable heterogeneity of their isoelectric points. We attempted to show that this heterogeneity was attributable to variable glycosylation of a single polypeptide chain. When peritoneal exudate cells were stimulated to make pyrogens in the presence of 2-deoxy-D-glucose, there was a relatively trivial suppression of pyrogen release, and analysis by isoelectric focusing showed parallel inhibition of secretion of a...

Bovine pancreatic polypeptide (bPP) undergoes significant changes in conformation and dynamics upon binding to DPC micelles.

Science.gov (United States)

Lerch, Mirjam; Gafner, Verena; Bader, Reto; Christen, Barbara; Folkers, Gerd; Zerbe, Oliver

2002-10-04

The pancreatic polypeptide (PP), a 36-residue, C-terminally amidated polypeptide hormone is a member of the neuropeptide Y (NPY) family. Here, we have studied the structure and dynamics of bovine pancreatic polypeptide (bPP) when bound to DPC-micelles as a membrane-mimicking model as well as the dynamics of bPP in solution. The comparison of structure and dynamics of bPP in both states reveals remarkable differences. The overall correlation time of 5.08ns derived from the 15N relaxation data proves unambiguously that bPP in solution exists as a dimer. Therein, intermolecular as well as intramolecular hydrophobic interactions from residues of both the amphiphilic helix and of the back-folded N terminus contribute to the stability of the PP fold. The overall rigidity is well-reflected in positive values for the heteronuclear NOE for residues 4-34. The membrane-bound species displays a partitioning into a more flexible N-terminal region and a well-defined alpha-helical region comprising residues 17-31. The average RMSD value for residues 17-31 is 0.22(+/-0.09)A. The flexibility of the N terminus is compatible with negative values of the heteronuclear NOE observed for the N-terminal residues 4-12 and low values of the generalized order parameter S(2). The membrane-peptide interface was investigated by micelle-integrating spin-labels and H,2H exchange measurements. It is formed by those residues which make contacts between the C-terminal alpha-helix and the polyproline helix. In contrast to pNPY, also residues from the N terminus display spatial proximity to the membrane interface. Furthermore, the orientation of the C terminus, that presumably contains residues involved in receptor binding, is different in the two environments. We speculate that this pre-positioning of residues could be an important requirement for receptor activation. Moreover, we doubt that the PP fold is of functional relevance for binding at the Y(4) receptor.

Gastric inhibitory polypeptide does not inhibit gastric emptying in humans

DEFF Research Database (Denmark)

Meier, Juris J; Goetze, Oliver; Anstipp, Jens

2004-01-01

) = 0.15, P = 0.15 for intact GIP; r(2) = 0.21, P = 0.086 for total GIP). We conclude that gastric emptying does not appear to be influenced by GIP. The secretion of GIP after meal ingestion is not suppressed by its exogenous administration. The lack of effect of GIP on gastric emptying underlines......The insulinotropic gut hormone gastric inhibitory polypeptide (GIP) has been demonstrated to inhibit gastric acid secretion and was proposed to possess "enterogastrone" activity. GIP effects on gastric emptying have not yet been studied. Fifteen healthy male volunteers (23.9 +/- 3.3 yr, body mass....... Gastric emptying was calculated from the (13)CO(2) exhalation rates in breath samples collected over 360 min. Venous blood was drawn in 30-min intervals for the determination of glucose, insulin, C-peptide, and GIP (total and intact). Statistical calculations were made by use of repeated-measures ANOVA...

Post-translational Introduction of D-Alanine into Ribosomally Synthesized Peptides by the Dehydroalanine Reductase NpnJ.

Science.gov (United States)

Yang, Xiao; van der Donk, Wilfred A

2015-10-07

Ribosomally synthesized peptides are generally limited to L-amino acid building blocks. Given the advantageous properties of peptides containing D-amino acids such as stabilization of certain turns and against proteolytic degradation, methods to introduce D-stereocenters are valuable. Here we report the first in vitro reconstitution and characterization of a dehydrogenase that carries out the asymmetric reduction of dehydroalanine. NpnJA reduces dehydroalanine to D-Ala using NAPDH as cosubstrate. The enzyme displays high substrate tolerance allowing introduction of D-Ala into a range of non-native substrates. In addition to the in vitro reactions, we describe five examples of using Escherichia coli as biosynthetic host for D-alanine introduction into ribosomal peptides. A deuterium-label-based coupled-enzyme assay was used to rapidly determine the stereochemistry of the newly installed alanine.

Pituitary adenylate cyclase-activating polypeptide: occurrence and relaxant effect in female genital tract

DEFF Research Database (Denmark)

Steenstrup, B R; Alm, P; Hannibal, J

1995-01-01

The distribution, localization, and smooth muscle effects of pituitary adenylate cyclase-activating polypeptide (PACAP) were studied in the human female genital tract. The concentrations of PACAP-38 and PACAP-27 were measured by radioimmunoassays, and both peptides were found throughout the genital...... was observed. The findings suggest a smooth muscle regulatory role of PACAP in the human female reproductive tract....... tract. The highest concentrations of PACAP-38 were detected in the ovary, the upper part of vagina, and the perineum. The concentrations of PACAP-27 were generally low, in some regions below the detection limit and in other regions 1 to 5% of the PACAP-38 concentrations. Immunocytochemistry revealed...

Aspects of structural landscape of human islet amyloid polypeptide

Energy Technology Data Exchange (ETDEWEB)

He, Jianfeng, E-mail: hjf@bit.edu.cn; Dai, Jin, E-mail: daijing491@gmail.com [School of Physics, Beijing Institute of Technology, Beijing 100081 (China); Li, Jing, E-mail: jinglichina@139.com [Institute of Biopharmaceutical Research, Yangtze River Pharmaceutical Group Beijing Haiyan Pharmaceutical Co., Ltd, Beijing 102206 (China); Peng, Xubiao, E-mail: xubiaopeng@gmail.com [Department of Physics and Astronomy, Uppsala University, P.O. Box 803, S-75108 Uppsala (Sweden); Niemi, Antti J., E-mail: Antti.Niemi@physics.uu.se [School of Physics, Beijing Institute of Technology, Beijing 100081 (China); Department of Physics and Astronomy, Uppsala University, P.O. Box 803, S-75108 Uppsala (Sweden); Laboratoire de Mathematiques et Physique Theorique CNRS UMR 6083, Fédération Denis Poisson, Université de Tours, Parc de Grandmont, F37200 Tours (France)

2015-01-28

The human islet amyloid polypeptide (hIAPP) co-operates with insulin to maintain glycemic balance. It also constitutes the amyloid plaques that aggregate in the pancreas of type-II diabetic patients. We have performed extensive in silico investigations to analyse the structural landscape of monomeric hIAPP, which is presumed to be intrinsically disordered. For this, we construct from first principles a highly predictive energy function that describes a monomeric hIAPP observed in a nuclear magnetic resonance experiment, as a local energy minimum. We subject our theoretical model of hIAPP to repeated heating and cooling simulations, back and forth between a high temperature regime where the conformation resembles a random walker and a low temperature limit where no thermal motions prevail. We find that the final low temperature conformations display a high level of degeneracy, in a manner which is fully in line with the presumed intrinsically disordered character of hIAPP. In particular, we identify an isolated family of α-helical conformations that might cause the transition to amyloidosis, by nucleation.

Protective effect of topically applied polypeptide from Chlamys farreri against ultraviolet radiation-induced chronic skin damage in guinea pig

Science.gov (United States)

Chi, Mingliang; Cao, Pengli; Yu, Guoying; Zhu, Li; Wang, Yuejun; Wang, Chunbo

2003-12-01

Polypeptide from Chlamys farreri (PCF), a topical polypeptide isolated from Chlamys farreri, was used in this experiment aimed to investigate the photoprotective effect of PCF against chronic skin damage induced by ultraviolet A (UVA) and ultraviolet B (UVB) radiation. The chronic ultraviolet-irradiated guinea pig model was established, and visible changes in the skin including wrinkling, sagging and erythema were observed. Malondialdehyde (MDA) and antioxidant enzymes including superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) in the dorsal skin were determined using biochemical methods. The results showed: (1) PCF (5 % and 20%) could greatly protect the dorsal skin of guinea pig against wrinkling, sagging and erythema induced by UV radiation in a concentration-dependent manner. (2) PCF could reduce MDA formation in the dorsal skin caused by UV irradiation, while increasing the activities of SOD and GSH-px. (3) The differences among the PCF groups and UV model group were significant ( Psolar UV spectrum photoprotection; and that the antioxidant property of PCF might play a role in photoprotection.

Identification and antigenic characterization of virulence-associated, plasmid-coded proteins of Shigella spp. and enteroinvasive Escherichia coli.

OpenAIRE

Hale, T L; Oaks, E V; Formal, S B

1985-01-01

Seven plasmid-coded polypeptides, designated a through g, were identified by two-dimensional nonequilibrium pH gradient electrophoresis of radiolabeled extracts from minicells of virulent Shigella flexneri serotypes 2a and 5 and enteroinvasive Escherichia coli O143. These polypeptides were deemed to be products of 140-megadalton (MDa) virulence-associated plasmids because they were not synthesized in minicells which were not harboring a 140-MDa plasmid or in minicells which were carrying an F...

Zwitterionic states in gas-phase polypeptide ions revealed by 157-nm ultra-violet photodissociation

DEFF Research Database (Denmark)

Kjeldsen, Frank; Silivra, Oleg A; Zubarev, Roman A

2006-01-01

carboxylic groups relative to competing COOH losses (45 Da) from neutral carboxylic groups. Loss of CO2 is a strong indication of the presence of a zwitterionic [(+)...(-)...(+)] salt bridge in the gas-phase polypeptide cation. This method provides a tool for studying, for example, the nature of binding...... of the fragment formation should be taken into account. Cations of Trp-cage proteins exist preferentially as zwitterions, with the deprotonation position divided between the Asp9 residue and the C terminus in the ratio 3:2. The majority of dications of the same molecule are not zwitterions. Furthermore, 157-nm...

In silico engineering of aggregation-prone recombinant proteins for substrate recognition by the chaperonin GroEL.

Science.gov (United States)

Kumar, Vipul; Punetha, Ankita; Sundar, Durai; Chaudhuri, Tapan K

2012-01-01

Molecular chaperones appear to have been evolved to facilitate protein folding in the cell through entrapment of folding intermediates on the interior of a large cavity formed between GroEL and its co-chaperonin GroES. They bind newly synthesized or non-native polypeptides through hydrophobic interactions and prevent their aggregation. Some proteins do not interact with GroEL, hence even though they are aggregation prone, cannot be assisted by GroEL for their folding. In this study, we have attempted to engineer these non-substrate proteins to convert them as the substrate for GroEL, without compromising on their function. We have used a computational biology approach to generate mutants of the selected proteins by selectively mutating residues in the hydrophobic patch, similar to GroES mobile loop region that are responsible for interaction with GroEL, and compared with the wild counterparts for calculation of their instability and aggregation propensities. The energies of the newly designed mutants were computed through molecular dynamics simulations. We observed increased aggregation propensity of some of the mutants formed after replacing charged amino acid residues with hydrophobic ones in the well defined hydrophobic patch, raising the possibility of their binding ability to GroEL. The newly generated mutants may provide potential substrates for Chaperonin GroEL, which can be experimentally generated and tested for their tendency of aggregation, interactions with GroEL and the possibility of chaperone-assisted folding to produce functional proteins.

Structural stability of Amandin, a major allergen from almond (Prunus dulcis), and its acidic and basic polypeptides.

Science.gov (United States)

Albillos, Silvia M; Menhart, Nicholas; Fu, Tong-Jen

2009-06-10

Information relating to the resistance of food allergens to thermal and/or chemical denaturation is critical if a reduction in protein allergenicity is to be achieved through food-processing means. This study examined the changes in the secondary structure of an almond allergen, amandin, and its acidic and basic polypeptides as a result of thermal and chemical denaturation. Amandin ( approximately 370 kDa) was purified by cryoprecipitation followed by gel filtration chromatography and subjected to thermal (13-96 degrees C) and chemical (urea and dithiothreitol) treatments. Changes in the secondary structure of the protein were followed using circular dichroism spectroscopy. The secondary structure of the hexameric amandin did not undergo remarkable changes at temperatures up to 90 degrees C, although protein aggregation was observed. In the presence of a reducing agent, irreversible denaturation occurred with the following experimental values: T(m) = 72.53 degrees C (transition temperature), DeltaH = 87.40 kcal/mol (unfolding enthalpy), and C(p) = 2.48 kcal/(mol degrees C) (heat capacity). The concentration of urea needed to achieve 50% denaturation was 2.59 M, and the Gibbs free energy of chemical denaturation was calculated to be DeltaG = 3.82 kcal/mol. The basic and acidic polypeptides of amandin had lower thermal stabilities than the multimeric protein.

Confidence in leadership among the newly qualified.

Science.gov (United States)

Bayliss-Pratt, Lisa; Morley, Mary; Bagley, Liz; Alderson, Steven

2013-10-23

The Francis report highlighted the importance of strong leadership from health professionals but it is unclear how prepared those who are newly qualified feel to take on a leadership role. We aimed to assess the confidence of newly qualified health professionals working in the West Midlands in the different competencies of the NHS Leadership Framework. Most respondents felt confident in their abilities to demonstrate personal qualities and work with others, but less so at managing or improving services or setting direction.

A multiscale model to evaluate the efficacy of anticancer therapies based on chimeric polypeptide nanoparticles

Science.gov (United States)

Paiva, L. R.; Martins, M. L.

2011-01-01

A multiscale model for tumor growth and its chemotherapy using conjugate nanoparticles is presented, and the corresponding therapeutic outcomes are evaluated. It is found that doxorubicin assembled into chimeric polypeptide nanoparticles cannot eradicate either vascularized primary tumors or avascular micrometastasis even administrated at loads close to their maximum tolerated doses. Furthermore, an effective and safety treatment demands for conjugate nanoparticles targeted to the malignant cells with much higher specificity and affinity than those currently observed in order to leave most of the normal tissues unaffected and to ensure a fast intracellular drug accumulation.

Pituitary adenylate cyclase activating polypeptide induces vascular relaxation and inhibits non-vascular smooth muscle activity in the rabbit female genital tract

DEFF Research Database (Denmark)

Steenstrup, B R; Ottesen, B; Jørgensen, M

1994-01-01

In vitro effects of two bioactive forms of pituitary adenylate cyclase activating polypeptide (PACAP): PACAP-38 and PACAP-27 were studied on rabbit vascular and non-vascular smooth muscle. Segments of the ovarian artery and muscle strips from the fallopian tube were used. Two series of experiment...

Short term aerobic exercise training increases postprandial pancreatic polypeptide but not peptide YY concentrations in obese individuals

OpenAIRE

Kanaley, Jill A.; Heden, Timothy D.; Liu, Ying; Whaley-Connell, Adam T.; Chockalingam, Anand; Dellsperger, Kevin C.; Fairchild, Timothy J.

2013-01-01

Objective Short-term exercise training improves glycemic control, but the effect of short-term training on postprandial satiety peptide responses or perceived satiety remains unknown. We tested the hypothesis that short-term aerobic exercise training (15 days) would alter postprandial pancreatic and gut peptide [pancreatic polypeptide (PP) and peptide YY (PYY)] responses and perceived appetite and satiety in obese individuals. Subjects Thirteen healthy obese men and women (age: 42±2 y; BMI: 3...

Newly synthesized benzanthrone derivatives as prospective fluorescent membrane probes

International Nuclear Information System (INIS)

Zhytniakivska, Olga; Trusova, Valeriya; Gorbenko, Galyna; Kirilova, Elena; Kalnina, Inta; Kirilov, Georgiy; Kinnunen, Paavo

2014-01-01

Fluorescence spectral properties of a series of novel benzanthrone derivatives have been explored in lipid bilayers composed of zwitterionic lipid phosphatidylcholine (PC) and its mixtures with cholesterol (Chol) and anionic phospholipid cardiolipin (CL). Analysis of partition coefficients showed that all the examined compounds possess rather high lipid-associating ability, with the amidino derivatives exhibiting stronger membrane partitioning compared with the aminobenzanthrones. To understand how benzanthrone partition properties correlate with their structure, quantitative structure property relationship (QSPR) analysis was performed involving a range of quantum chemical molecular descriptors. -- Highlights: • Benzanthrone partitioning into lipid bilayer correlates with lipophilicity of the dyes. • Partition properties of benzanthrones depend on the dye dipole moment. • Amidino derivatives exhibit higher membrane affinity than aminobenzanthrones

CAMAC programmable-control frequency synthesizer

International Nuclear Information System (INIS)

Yumaguzin, T.Kh.; Vyazovkin, D.E.; Nazirov, Eh.P.; Tuktarov, R.F.

1989-01-01

Synthesizer allows to set frequency with 0.015% accuracy and to scan it with variable step. Frequency controlled divider with further summing-up of divided frequency with fundamental one is used in synthesizer, and it has allowed to use digit of the input code and to obtain 3-4 MHz frequency range. Variation of operation flowsheet in the other frequency range is possible. K-155 and K-531 series microcircuits were used during development

Problems faced by newly diagnosed diabetes mellitus patients at ...

African Journals Online (AJOL)

Diabetes mellitus can be a frightening experience for newly diagnosed patients. The aim of this study was to determine and describe the problems faced by newly diagnosed diabetes mellitus patients at primary healthcare facilities at Mopani district, Limpopo Province. A qualitative, descriptive and contextual research ...

Coulomb repulsion in short polypeptides.

Science.gov (United States)

Norouzy, Amir; Assaf, Khaleel I; Zhang, Shuai; Jacob, Maik H; Nau, Werner M

2015-01-08

Coulomb repulsion between like-charged side chains is presently viewed as a major force that impacts the biological activity of intrinsically disordered polypeptides (IDPs) by determining their spatial dimensions. We investigated short synthetic models of IDPs, purely composed of ionizable amino acid residues and therefore expected to display an extreme structural and dynamic response to pH variation. Two synergistic, custom-made, time-resolved fluorescence methods were applied in tandem to study the structure and dynamics of the acidic and basic hexapeptides Asp6, Glu6, Arg6, Lys6, and His6 between pH 1 and 12. (i) End-to-end distances were obtained from the short-distance Förster resonance energy transfer (sdFRET) from N-terminal 5-fluoro-l-tryptophan (FTrp) to C-terminal Dbo. (ii) End-to-end collision rates were obtained for the same peptides from the collision-induced fluorescence quenching (CIFQ) of Dbo by FTrp. Unexpectedly, the very high increase of charge density at elevated pH had no dynamical or conformational consequence in the anionic chains, neither in the absence nor in the presence of salt, in conflict with the common view and in partial conflict with accompanying molecular dynamics simulations. In contrast, the cationic peptides responded to ionization but with surprising patterns that mirrored the rich individual characteristics of each side chain type. The contrasting results had to be interpreted, by considering salt screening experiments, N-terminal acetylation, and simulations, in terms of an interplay of local dielectric constant and peptide-length dependent side chain charge-charge repulsion, side chain functional group solvation, N-terminal and side chain charge-charge repulsion, and side chain-side chain as well as side chain-backbone interactions. The common picture that emerged is that Coulomb repulsion between water-solvated side chains is efficiently quenched in short peptides as long as side chains are not in direct contact with each

Newly graduated nurses' use of knowledge sources in clinical decision-making

DEFF Research Database (Denmark)

Voldbjerg, Siri Lygum; Grønkjaer, Mette; Wiechula, Rick

2017-01-01

AIMS AND OBJECTIVES: To explore which knowledge sources newly graduated nurses' use in clinical decision-making and why and how they are used. BACKGROUND: In spite of an increased educational focus on skills and competencies within evidence based practice newly graduated nurses' ability to use...... approaches to strengthen the knowledgebase used in clinical decision-making. DESIGN AND METHODS: Ethnographic study using participant-observation and individual semi-structured interviews of nine Danish newly graduated nurses in medical and surgical hospital settings. RESULTS: Newly graduates use...... in clinical decision-making. If newly graduates are to be supported in an articulate and reflective use of a variety of sources, they have to be allocated to experienced nurses who model a reflective, articulate and balanced use of knowledge sources. This article is protected by copyright. All rights reserved....

Value of a newly sequenced bacterial genome

DEFF Research Database (Denmark)

Barbosa, Eudes; Aburjaile, Flavia F; Ramos, Rommel Tj

2014-01-01

and annotation will not be undertaken. It is important to know what is lost when we settle for a draft genome and to determine the "scientific value" of a newly sequenced genome. This review addresses the expected impact of newly sequenced genomes on antibacterial discovery and vaccinology. Also, it discusses...... heightened expectations that NGS would boost antibacterial discovery and vaccine development. Although many possible drug and vaccine targets have been discovered, the success rate of genome-based analysis has remained below expectations. Furthermore, NGS has had consequences for genome quality, resulting...

Distinct localization of FMRFamide- and bovine pancreatic polypeptide-like material in the brain, retrocerebral complex and suboesophageal ganglion of the cockroach Periplaneta americana L

DEFF Research Database (Denmark)

Verhaert, P; Grimmelikhuijzen, C J; De Loof, A

1985-01-01

One bovine pancreatic polypeptide (BPP) antiserum and two FMRFamide antisera were applied in the peroxidase-antiperoxidase (PAP) immunohistochemical technique on a complete series of sections of brains, suboesophageal ganglia (SOG), corpora cardiaca (CC) and corpora allata of Periplaneta americana...... L. Double immunohistochemical staining demonstrated that the same perikarya and processes were stained by both the BPP and FMRFamide antisera. This was caused by cross-reaction of the BPP and FMRFamide antisera with common antigenic determinants as was shown by a number of solid-phase absorptions....... Application of a third FMRFamide antiserum, which was especially selected for its inability to react with bovine and avian pancreatic polypeptide, showed that more than half of the structures that were stained with the 'unspecific' BPP and FMRFamide antisera, contained material which was genuinely FMRFamide...

Lectin Domains of Polypeptide GalNAc Transferases Exhibit Glycopeptide Binding Specificity

DEFF Research Database (Denmark)

Pedersen, Johannes W; Bennett, Eric P; Schjoldager, Katrine T-B G

2011-01-01

UDP-GalNAc:polypeptide a-N-acetylgalactosaminyltransferases (GalNAc-Ts) constitute a family of up to 20 transferases that initiate mucin-type O-glycosylation. The transferases are structurally composed of catalytic and lectin domains. Two modes have been identified for the selection...... of glycosylation sites by GalNAc-Ts: confined sequence recognition by the catalytic domain alone, and concerted recognition of acceptor sites and adjacent GalNAc-glycosylated sites by the catalytic and lectin domains, respectively. Thus far, only the catalytic domain has been shown to have peptide sequence...... on sequences of mucins MUC1, MUC2, MUC4, MUC5AC, MUC6, and MUC7 as well as a random glycopeptide bead library, we examined the binding properties of four different lectin domains. The lectin domains of GalNAc-T1, -T2, -T3, and -T4 bound different subsets of small glycopeptides. These results indicate...

Tuning Thermoresponsive Properties of Cationic Elastin-like Polypeptides by Varying Counterions and Side-Chains.

Science.gov (United States)

Petitdemange, Rosine; Garanger, Elisabeth; Bataille, Laure; Bathany, Katell; Garbay, Bertrand; Deming, Timothy J; Lecommandoux, Sébastien

2017-05-17

We report the synthesis of methionine-containing recombinant elastin-like polypeptides (ELPs) of different lengths that contain periodically spaced methionine residues. These ELPs were chemoselectively alkylated at all methionine residues to give polycationic derivatives. Some of these samples were found to possess solubility transitions in water, where the temperature of these transitions varied with ELP concentration, nature of the methionine alkylating group, and nature of the sulfonium counterions. These studies show that introduction and controlled spacing of methionine sulfonium residues into ELPs can be used as a means both to tune their solubility transition temperatures in water using a variety of different parameters and to introduce new side-chain functionality.

In vitro gamma irradiation of some purified polypeptide hormones and their biological and radioimmunological activity

International Nuclear Information System (INIS)

Hromadova, M.; Macho, L.; Strbak, V.; Vigas, M.; Mikulaj, L.

1979-01-01

Some polypeptide hormones (adrenocorticotropin - ACTH, human and bovine growth hormone - GH, human menopausal gonadotropin - HMG, human luteinizing hormone - LH, and bovine thyrotropin - TSH) were irradiated either with 2.5 or 12.5 Mrad (1.1 Mrad/h) or both and their biological activity or immunoreactivity was tested within few days or 3 to 5 months after irradiation. Biological activity of irradiated ACTH (estimation of corticosterone released into medium by incubated adrenals - Saffran and Schally 1955) was not decreased in both time intervals tested. Ten days after irradiation of bovine GH no changes in biological activity (tibia test - Wilhelmi 1973) were found. No decrease of biological activity of irradiated HMG (augmentation of ovarian and uterine weight - Butt 1973) was found 4 months after irradiation and, finaly, no decrease of bovine TSH activity (radioiodine release from prelabelled thyroid in mice - McKenzie 1958) was found 2 to 30 days after irradiation with 2.5 Mrad, while a decrease was observed after 12.5 Mrad. Three to five months after irradiation, however, there was a decrease of biological activity after both doses. The immunological reactivity of irradiated HMG and LH did not differ from that of nonirradiated samples. The same was found with human GH after 2.5 Mrad, while a decrease of reactivity after 12.5 Mrad was detected. It was concluded that, in most of cases, the sterilizing dose of gamma radiation (2.5 Mrad) did not affect the biological activity of polypeptide hormones and that their sensitivity to irradiation appears to differ. (author)

Corrosion inhibition of mild steel in acidic media using newly synthesized heterocyclic organic molecules: Correlation between inhibition efficiency and chemical structure

Energy Technology Data Exchange (ETDEWEB)

Ouici, H. B., E-mail: ouici.houari@yahoo.fr; Guendouzi, A., E-mail: guendouzzi@yahoo.fr [Departement of Chimistry, Faculty of Sciences, University of Saïda (Algeria); Benali, O. [Department of Biology, Faculty of Science, University of Saida (Algeria)

2015-03-30

The corrosion inhibition of mild steel in 5% HCl solutions by some new synthesized organic compounds namely 3-(2-methoxyphenyl) 5-mercapto-1. 2. 4-triazole (2-MMT), 3-(3-methoxyphenyl) 5-mercapto-1. 2. 4-triazole (3-MMT) and 3-(2-hydroxyphenyl) 5-mercapto-1. 2. 4-triazole (2-HMT) was investigated using weight loss and potentiostatic polarization techniques. These measurements reveal that the inhibition efficiency obtained by these compounds increased by increasing their concentration. The inhibition efficiency follows the order 2-MMT >3-MMT >2-HMT. Polarization studies show that these compounds are of the mixed type but dominantly act as a cathodic inhibitors for mild steel in 5% HCl solutions. These inhibitors function through adsorption following Langmuir isotherm. Activation energy and Gibbs free energy for adsorption of inhibitors are calculated. Molecular modeling has been conducted to correlate the corrosion inhibition properties with the calculated quantum chemical parameters.

Synthesizing Modular Invariants for Synchronous Code

Directory of Open Access Journals (Sweden)

Pierre-Loic Garoche

2014-12-01

Full Text Available In this paper, we explore different techniques to synthesize modular invariants for synchronous code encoded as Horn clauses. Modular invariants are a set of formulas that characterizes the validity of predicates. They are very useful for different aspects of analysis, synthesis, testing and program transformation. We describe two techniques to generate modular invariants for code written in the synchronous dataflow language Lustre. The first technique directly encodes the synchronous code in a modular fashion. While in the second technique, we synthesize modular invariants starting from a monolithic invariant. Both techniques, take advantage of analysis techniques based on property-directed reachability. We also describe a technique to minimize the synthesized invariants.

Heat-stable proteins and abscisic acid action in barley aleurone cells

International Nuclear Information System (INIS)

Jacobsen, J.V.; Shaw, D.C.

1989-01-01

[ 35 S]Methionine labeling experiments showed that abscisic acid (ABA) induced the synthesis of at least 25 polypeptides in mature barley (Hordeum vulgare) aleurone cells. The polypeptides were not secreted. Whereas most of the proteins extracted from aleurone cells were coagulated by heating to 100 degree C for 10 minutes, most of the ABA-induced polypeptides remained in solution (heat-stable). ABA had little effect on the spectrum of polypeptides that were synthesized and secreted by aleurone cells, and most of these secreted polypeptides were also heat-stable. Coomassie blue staining of sodium dodecyl sulfate polyacrylamide gels indicated that ABA-induced polypeptides already occurred in high amounts in mature aleurone layers having accumulated during grain development. About 60% of the total protein extracted from mature aleurone was heat stable. Amino acid analyses of total preparations of heat-stable and heat-labile proteins showed that, compared to heat-labile proteins, heat-stable intracellular proteins were characterized by higher glutamic acid/glutamine (Glx) and glycine levels and lower levels of neutral amino acids. Secreted heat-stable proteins were rich in Glx and proline. The possibilities that the accumulation of the heat-stable polypeptides during grain development is controlled by ABA and that the function of these polypeptides is related to their abundance and extraordinary heat stability are considered

Dual binding mode of the nascent polypeptide-associated complex reveals a novel universal adapter site on the ribosome.

Science.gov (United States)

Pech, Markus; Spreter, Thomas; Beckmann, Roland; Beatrix, Birgitta

2010-06-18

Nascent polypeptide-associated complex (NAC) was identified in eukaryotes as the first cytosolic factor that contacts the nascent polypeptide chain emerging from the ribosome. NAC is present as a homodimer in archaea and as a highly conserved heterodimer in eukaryotes. Mutations in NAC cause severe embryonically lethal phenotypes in mice, Drosophila melanogaster, and Caenorhabditis elegans. In the yeast Saccharomyces cerevisiae NAC is quantitatively associated with ribosomes. Here we show that NAC contacts several ribosomal proteins. The N terminus of betaNAC, however, specifically contacts near the tunnel exit ribosomal protein Rpl31, which is unique to eukaryotes and archaea. Moreover, the first 23 amino acids of betaNAC are sufficient to direct an otherwise non-associated protein to the ribosome. In contrast, alphaNAC (Egd2p) contacts Rpl17, the direct neighbor of Rpl31 at the ribosomal tunnel exit site. Rpl31 was also recently identified as a contact site for the SRP receptor and the ribosome-associated complex. Furthermore, in Escherichia coli peptide deformylase (PDF) interacts with the corresponding surface area on the eubacterial ribosome. In addition to the previously identified universal adapter site represented by Rpl25/Rpl35, we therefore refer to Rpl31/Rpl17 as a novel universal docking site for ribosome-associated factors on the eukaryotic ribosome.

Newly Generated Liquid Waste Processing Alternatives Study, Volume 1

Energy Technology Data Exchange (ETDEWEB)

Landman, William Henry; Bates, Steven Odum; Bonnema, Bruce Edward; Palmer, Stanley Leland; Podgorney, Anna Kristine; Walsh, Stephanie

2002-09-01

This report identifies and evaluates three options for treating newly generated liquid waste at the Idaho Nuclear Technology and Engineering Center of the Idaho National Engineering and Environmental Laboratory. The three options are: (a) treat the waste using processing facilities designed for treating sodium-bearing waste, (b) treat the waste using subcontractor-supplied mobile systems, or (c) treat the waste using a special facility designed and constructed for that purpose. In studying these options, engineers concluded that the best approach is to store the newly generated liquid waste until a sodium-bearing waste treatment facility is available and then to co-process the stored inventory of the newly generated waste with the sodium-bearing waste. After the sodium-bearing waste facility completes its mission, two paths are available. The newly generated liquid waste could be treated using the subcontractor-supplied system or the sodium-bearing waste facility or a portion of it. The final decision depends on the design of the sodium-bearing waste treatment facility, which will be completed in coming years.

Vasoactive intestinal polypeptide (VIP) innervation of the human eyelid glands.

Science.gov (United States)

Seifert, P; Spitznas, M

1999-06-01

This study was conducted to obtain morphological proof of innervating nerve fibres in the glands of the human eyelid (accessory lacrimal glands of Wolfring, meibomian glands, goblet cells, glands of Zeis, glands of Moll, sweat glands, glands of lanugo hair follicles) and identification of the secretomotorically active neuropeptide vasoactive intestinal polypeptide (VIP) as a common transmitter. Epoxy-embedded ultrathin sections of tissue samples from human eyelids were studied using electron microscopy. Paraffin sections fixed in Bouin-Hollande solution were immunostained with rabbit antiserum against VIP. With the electron microscope we were able to identify nerves in the glandular stroma of all the glands examined with the exception of goblet cells. Intraepithelial single axons were only seen in the parenchyma of Wolfring glands. The morphological findings corresponded with the immunological finding of VIP-positive, nerve-like structures in the same locations, with the exception of lanugo hair follicle glands, and goblet cells. Our findings indicate that the glands of the eyelids and main lacrimal gland represent a functional unit with VIP as a possible common stimulating factor. Copyright 1999 Academic Press.

Pituitary adenylate cyclase-activating polypeptide precursor is processed solely by prohormone convertase 4 in the gonads.

Science.gov (United States)

Li, M; Mbikay, M; Arimura, A

2000-10-01

Pituitary adenylate cyclase-activating polypeptide (PACAP) is abundant not only in the brain, but also in the testis. Immunohistochemical studies have shown that PACAP-LI in rat testis is expressed stage specifically in spermatids. This suggests that testicular PACAP participates in the regulatory mechanism of spermatogenesis. Additionally, the ovary contains a relatively small amount of PACAP, conceivably involved in the regulation of folliculogenesis. PACAP is synthesized as a preprohormone and is processed by prohormone convertases, such as PC1, PC2, and PC4. PC4 is expressed only in the testis and ovary, where neither PC1 nor PC2 is expressed. However, whether PC4 is the sole endoprotease for the PACAP precursor in the gonads remains unknown. Recent studies using PC4-transgenic mice revealed that male PC4-null mice exhibited severely impaired fertility, although spermatogenesis appeared to be normal. The female PC4-null mice exhibited delayed folliculogenesis in the ovaries. To examine whether PC4 is the sole processing enzyme for the PACAP precursor in the gonads, we analyzed testicular and ovarian extracts from the PC4-null and wild-type mice for PACAP (PACAP38 and PACAP27) and its messenger RNA using reverse phase HPLC combined with specific RIAs and ribonuclease protection assay, respectively. For RIAs, three different polyclonal antisera with different recognition sites were used to identify PACAP38, PACAP27, and its precursor. Neither the testis nor the ovary from the PC4-null mice expressed PACAP38 or PACAP27, but the levels of PACAP transcripts in the testis and ovary of homozygous PC4-deficient mice were considerably elevated compared with those of the wild-type and heterozygous animals. The findings indicate that PC4 is the sole processing enzyme for the precursor of PACAP in the testis and ovary of mice. The possibility that the absence of bioactive PACAP in the testis and ovary of PC4-null mice caused severely impaired fertility in the males and

Characterization of a dermatan sulfate proteoglycan synthesized by murine parietal yolk sac (PYS-2) cells

DEFF Research Database (Denmark)

Couchman, J R; Woods, A; Höök, M

1985-01-01

-polyacrylamide gel electrophoresis of chondroitinase ABC-treated 125I-labeled proteoglycan reveals two polypeptides with molecular weights of 34,000 and 27,000. Results from papain digestion of the proteoglycan suggest that most of the polysaccharide chains are clustered at a papain-resistant segment of the core...

Development of the kits for RIA simultaneous determination of polypeptide hormones

International Nuclear Information System (INIS)

Szybinski, Z.

1982-12-01

A simple and universal modification of chloramine T technique has been developed for the radioactive iodination of several polypeptide hormones such as insulin, human growth hormone (HGH), human TSH, synthetic human gastrin and beta-endorphine. The prepared products proved to have good immunoreactivity suitable for RIA purposes. The technique is inexpensive and quick. A new procedure has also been worked out utilizing horse myeloperoxidase in solid state as catalyser. The hormones iodinated with this technique show better parameters (e.g. longer stability, better binding to antibody, more favourable adsorption on dextran-coated charcoal); however the specific activities achieved were lower. The possibilities of simultaneous measurement of insulin and HGH have been studied. In this connection, a comparatively simple method for the determination of the endogenous anti-insulin antibodies was developed and used for the control of patients with diabetes and for the checking of new insulin preparations. However, the technique requires relatively sophisticated equipment and computerized calculations

CS5931, a Novel Polypeptide in Ciona savignyi, Represses Angiogenesis via Inhibiting Vascular Endothelial Growth Factor (VEGF and Matrix Metalloproteinases (MMPs

Directory of Open Access Journals (Sweden)

Ge Liu

2014-03-01

Full Text Available CS5931 is a novel polypeptide from Ciona savignyi with anticancer activities. Previous study in our laboratory has shown that CS5931 can induce cell death via mitochondrial apoptotic pathway. In the present study, we found that the polypeptide could inhibit angiogenesis both in vitro and in vivo. CS5931 inhibited the proliferation, migration and formation of capillary-like structures of HUVECs (Human Umbilical Vein Endothelial Cell in a dose-dependent manner. Additionally, CS5931 repressed spontaneous angiogenesis of the zebrafish vessels. Further studies showed that CS5931 also blocked vascular endothelial growth factor (VEGF production but without any effect on its mRNA expression. Moreover, CS5931 reduced the expression of matrix metalloproteinases (MMP-2 and MMP-9 both on protein and mRNA levels in HUVEC cells. We demonstrated that CS5931 possessed strong anti-angiogenic activity both in vitro and in vivo, possible via VEGF and MMPs. This study indicates that CS5931 has the potential to be developed as a novel therapeutic agent as an inhibitor of angiogenesis for the treatment of cancer.

Loss of UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 3 and reduced O-glycosylation in colon carcinoma cells selected for hepatic metastasis

DEFF Research Database (Denmark)

Kato, Kentaro; Takeuchi, Hideyuki; Kanoh, Akira

2010-01-01

O-glycosylation of mucin is initiated by the attachment of N-acetyl-D-galactosamine (GalNAc) to serine or threonine residues in mucin core polypeptides by UDPGalNAc:polypeptide N-acetylgalactosaminyltransferases (ppGalNAc-Ts). It is not well understood how GalNAc attachment is regulated by multiple...... ppGalNAc-Ts in each cell. In the present study, the expression levels of murine ppGalNAc-Ts (mGalNAc-Ts), T1, T2, T3, T4, T6, and T7 were compared between mouse colon carcinoma colon 38 cells and variant SL4 cells, selected for their metastatic potentials, by using the competitive RT-PCR method....... The expression levels of mGalNAc-T1, T2, and T7 were slightly higher in the SL4 cells than in the colon 38 cells, whereas the expression level of mGalNAc-T3 in the SL4 cells was 1.5% of that in the colon 38 cells. Products of enzymatic incorporations of GalNAc residues into FITCPTTTPITTTTK peptide by the use...

Observation of the bone mineral density of newly formed bone using rabbits. Compared with newly formed bone around implants and cortical bone

International Nuclear Information System (INIS)

Nakada, Hiroshi; Numata, Yasuko; Sakae, Toshiro; Tamaki, Hiroyuki; Kato, Takao

2009-01-01

There have been many studies reporting that newly formed bone around implants is spongy bone. However, although the morphology is reported as being like spongy bone, it is difficult to discriminate whether the bone quality of newly formed bone appears similar to osteoid or cortical bone; therefore, evaluation of bone quality is required. The aims of this study were to measure the bone mineral density (BMD) values of newly formed bone around implants after 4, 8, 16, 24 and 48 weeks, to represent these values on three-dimensional color mapping (3Dmap), and to evaluate the change in bone quality associated with newly formed bone around implants. The animal experimental protocol of this study was approved by the Ethics Committee for Animal Experiments of our University. This experiment used 20 surface treatment implants (Ti-6Al-4V alloy: 3.1 mm in diameter and 30.0 mm in length) by grit-blasting. They were embedded into surgically created flaws in femurs of 20 New Zealand white rabbits (16 weeks old, male). The rabbits were sacrificed with an ear intravenous overdose of pentobarbital sodium under general anesthesia each period, and the femurs were resected. We measured BMD of newly formed bone around implants and cortical bone using Micro-CT, and the BMD distribution map of 3Dmap (TRI/3D Bon BMD, Ratoc System Engineering). The BMD of cortical bone was 1,026.3±44.3 mg/cm 3 at 4 weeks, 1,023.8±40.9 mg/cm 3 at 8 weeks, 1,048.2±45.6 mg/cm 3 at 16 weeks, 1,067.2±60.2 mg/cm 3 at 24 weeks, and 1,069.3±50.7 mg/cm 3 at 48 weeks after implantation, showing a non-significant increase each period. The BMD of newly formed bone around implants was 296.8±25.6 mg/cm 3 at 4 weeks, 525.0±72.4 mg/cm 3 at 8 weeks, 691.2±26.0 mg/cm 3 at 16 weeks, 776.9±27.7 mg/cm 3 at 24 weeks, and 845.2±23.1 mg/cm 3 at 48 weeks after implantation, showing a significant increase after each period. It was revealed that the color scale of newly formed bone was Low level at 4 weeks, and then it

Experimental and theoretical studies on tautomeric structures of a newly synthesized 2,2‧(hydrazine-1,2-diylidenebis(propan-1-yl-1-ylidene))diphenol

Science.gov (United States)

Karakurt, Tuncay; Cukurovali, Alaaddin; Subasi, Nuriye Tuna; Onaran, Abdurrahman; Ece, Abdulilah; Eker, Sıtkı; Kani, Ibrahim

2018-02-01

In the present study, a single crystal of a Schiff base, 2,2‧(hydrazine-1,2-diylidenebis(propan-1-yl-1-ylidene))diphenol, was synthesized. The structure of the synthesized crystal was confirmed by 1H and 13C NMR spectroscopic and X-ray diffraction analysis techniques. Experimental and theoretical studies were carried out on two tautomeric structures. It has been observed that the title compound studied can be in two different tautomeric forms, phenol-imine and keto-amine. Theoretical calculations have been performed to support experimental results. Accordingly, the geometric parameters of the compound were optimized by the density functional theory (DFT) method using the Gaussian 09 and Quantum Espresso (QE) packet program was used for periodic boundary conditions (PBC) studies. Furthermore, the compound was also tested for in vitro antifungal activity against Sclerotinia sclerotiorum, Alternaria solani, Fusarium oxysporum f. sp. lycopersici and Monilinia fructigena plant pathogens. Promising inhibition profiles were observed especially towards A. solani. Finally, molecular docking studies and post-docking procedure based on Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) were also carried out to get insight into the compound's binding interactions with the potential. Although theoretical calculations showed that the phenol-imine form was more stable, keto-amine form was predicted to have better binding affinity which was concluded to result from loss of rotational entropy in phenol-imine upon binding. The results obtained here from both experimental and computational methods might serve as a potential lead in the development of novel anti-fungal agents.

The practical skills of newly qualified nurses.

Science.gov (United States)

Danbjørg, Dorthe Boe; Birkelund, Regner

2011-02-01

This paper reports the findings from a study of newly qualified nurses and which subjects the nurses regarded as the most important in order to be able to live up to the requirements of clinical practice, and how they experience their potential for developing practical and moral skills, after the decrease in practical training. A qualitative approach guided the research process and the analysis of the data. The data was collected by participant observation and qualitative interviews with four nurses as informants. The conclusions made in this study are based on the statements and the observations of the newly qualified nurses. Our findings are discussed in relation to the Aristotelian concept and other relevant literature. The main message is that the newly qualified nurses did not feel equipped when they finished their training. This could be interpreted as a direct consequence of the decrease in practical training. Our study also underlines that the way nursing theory is perceived and taught is problematic. The interviews revealed that the nurses think that nursing theories should be applied directly in practice. This misunderstanding is probably also applicable to the teachers of the theories. Copyright © 2010 Elsevier Ltd. All rights reserved.

Protein Complexation and pH Dependent Release Using Boronic Acid Containing PEG-Polypeptide Copolymers.

Science.gov (United States)

Negri, Graciela E; Deming, Timothy J

2017-01-01

New poly(L-lysine)-b-poly(ethylene glycol) copolypeptides have been prepared, where the side-chain amine groups of lysine residues are modified to contain ortho-amine substituted phenylboronic acid, i.e., Wulff-type phenylboronic acid (WBA), groups to improve their pH responsive, carbohydrate binding properties. These block copolymers form nanoscale complexes with glycosylated proteins that are stable at physiological pH, yet dissociate and release the glycoproteins under acidic conditions, similar to those found in endosomal and lysosomal compartments within cells. These results suggest that WBA modified polypeptide copolymers are promising for further development as degradable carriers for intracellular protein delivery. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Angioplastic necrolytic migratory erythema. Unique association of necrolytic migratory erythema, extensive angioplasia, and high molecular weight glucagon-like polypeptide

International Nuclear Information System (INIS)

Franchimont, C.; Pierard, G.E.; Luyckx, A.S.; Gerard, J.; Lapiere, C.M.

1982-01-01

A diabetic patient developed necrolytic migratory erythema with extensive angioplasia and high molecular weight glucagon-like polypeptide. There was no associated neoplasm such as glucagonoma. Lesions in the skin were studied by standard optical microscopy and by radioautography after incorporation of tritiated thymidine. Alterations in the skin begin as focal necrosis in the epidermis and in epithelial structures of adnexa, followed by marked angioplasia and a superficial and deep perivascular dermatitis

Newly graduated nurses' use of knowledge sources: a meta-ethnography.

Science.gov (United States)

Voldbjerg, Siri Lygum; Grønkjaer, Mette; Sørensen, Erik Elgaard; Hall, Elisabeth O C

2016-08-01

To advance evidence on newly graduated nurses' use of knowledge sources. Clinical decisions need to be evidence-based and understanding the knowledge sources that newly graduated nurses use will inform both education and practice. Qualitative studies on newly graduated nurses' use of knowledge sources are increasing though generated from scattered healthcare contexts. Therefore, a metasynthesis of qualitative research on what knowledge sources new graduates use in decision-making was conducted. Meta-ethnography. Nineteen reports, representing 17 studies, published from 2000-2014 were identified from iterative searches in relevant databases from May 2013-May 2014. Included reports were appraised for quality and Noblit and Hare's meta-ethnography guided the interpretation and synthesis of data. Newly graduated nurses' use of knowledge sources during their first 2-year postgraduation were interpreted in the main theme 'self and others as knowledge sources,' with two subthemes 'doing and following' and 'knowing and doing,' each with several elucidating categories. The metasynthesis revealed a line of argument among the report findings underscoring progression in knowledge use and perception of competence and confidence among newly graduated nurses. The transition phase, feeling of confidence and ability to use critical thinking and reflection, has a great impact on knowledge sources incorporated in clinical decisions. The synthesis accentuates that for use of newly graduated nurses' qualifications and skills in evidence-based practice, clinical practice needs to provide a supportive environment which nurtures critical thinking and questions and articulates use of multiple knowledge sources. © 2016 John Wiley & Sons Ltd.

Assessment voice synthesizers for reading in digital books

Directory of Open Access Journals (Sweden)

Sérvulo Fernandes da Silva Neto

2013-07-01

Full Text Available The digital accessibility shows ways to information access in digital media that assist people with different types of disabilities to a better interaction with the computer independent of its limitations. Of these tools are composed by voice synthesizers, that supposedly simplifying their access to any recorded knowledge through digital technologies. However such tools have emerged originally in countries foreign language. Which brings us to the following research problem: the voice synthesizers are appropriate for reading digital books in the Portuguese language? The objective of this study was to analyze and classify different software tools voice synthesizers in combination with software digital book readers to support accessibility to e-books in Portuguese. Through literature review were identified applications software voice synthesizers, composing the sample analyzed in this work. We used a simplified version of the method of Multiple Criteria Decision Support - MMDA, to assess these. In the research 12 were considered readers of e-books and 11 software voice synthesizer, tested with six formats of e-books (E-pub, PDF, HTML, DOC, TXT, and Mobi. In accordance with the results, the software Virtual Vision achieved the highest score. Relative to formats, it was found that the PDF has measured a better score when summed the results of the three synthesizers. In the studied universe contacted that many synthesizers simply cannot be used because they did not support the Portuguese language.

Perception of Paralinguistic Traits in Synthesized Voices

DEFF Research Database (Denmark)

Baird, Alice Emily; Hasse Jørgensen, Stina; Parada-Cabaleiro, Emilia

2017-01-01

Along with the rise of artificial intelligence and the internet-of-things, synthesized voices are now common in daily–life, providing us with guidance, assistance, and even companionship. From formant to concatenative synthesis, the synthesized voice continues to be defined by the same traits we...

Design of a software for calculating isoelectric point of a polypeptide according to their net charge using the graphical programming language LabVIEW.

Science.gov (United States)

Tovar, Glomen

2018-01-01

A software to calculate the net charge and to predict the isoelectric point (pI) of a polypeptide is developed in this work using the graphical programming language LabVIEW. Through this instrument the net charges of the ionizable residues of the polypeptide chains of the proteins are calculated at different pH values, tabulated, pI is predicted and an Excel (-xls) type file is generated. In this work, the experimental values of the pIs (pI) of different proteins are compared with the values of the pIs (pI) calculated graphically, achieving a correlation coefficient (R) of 0.934746 which represents a good reliability for a p program can constitute an instrument applicable in the laboratory, facilitating the calculation to graduate students and junior researchers. © 2017 by The International Union of Biochemistry and Molecular Biology, 46(1):39-46, 2018. © 2017 The International Union of Biochemistry and Molecular Biology.

The impact of organisational culture on the adaptation of newly ...

African Journals Online (AJOL)

Usually newly employed nurses find adjusting to a work setting a challenging experience. Their successful adaptation to their work situation is greatly influenced by the socialisation process inherent in the organisational culture. The newly employed nurse often finds that the norms are unclear, confusing and restrictive.

Raman assisted lightwave synthesized frequency sweeper

DEFF Research Database (Denmark)

Pedersen, Anders Tegtmeier; Rottwitt, Karsten

2010-01-01

We present a Lightwave Synthesized Frequency Sweeper comprising a Raman amplifier for loss compensation. The generated pulse train contains 123 pulses and has a flat signal level as well as a low noise level.......We present a Lightwave Synthesized Frequency Sweeper comprising a Raman amplifier for loss compensation. The generated pulse train contains 123 pulses and has a flat signal level as well as a low noise level....

Protein synthesis directed by cowpea mosaic virus RNAs

International Nuclear Information System (INIS)

Stuik, E.

1979-01-01

The thesis concerns the proteins synthesized under direction of Cowpea mosaic virus RNAs. Sufficient radioactive labelling of proteins was achieved when 35 S as sulphate was administered to intact Vigna plants, cultivated in Hoagland solution. The large polypeptides synthesized under direction of B- and M-RNA are probably precursor molecules from which the coat proteins are generated by a mechanism of posttranslational cleavage. (Auth.)

NMR structure of the glucose-dependent insulinotropic polypeptide fragment, GIP(1-30)amide

International Nuclear Information System (INIS)

Alana, Inigo; Hewage, Chandralal M.; G. Malthouse, J. Paul; Parker, Jeremy C.; Gault, Victor A.; O'Harte, Finbarr P.M.

2004-01-01

Glucose-dependent insulinotropic polypeptide is an incretin hormone that stimulates insulin secretion and reduces postprandial glycaemic excursions. The glucose-dependent action of GIP on pancreatic β-cells has attracted attention towards its exploitation as a potential drug for type 2 diabetes. Use of NMR or X-ray crystallography is vital to determine the three-dimensional structure of the peptide. Therefore, to understand the basic structural requirements for the biological activity of GIP, the solution structure of the major biologically active fragment, GIP(1-30)amide, was investigated by proton NMR spectroscopy and molecular modelling. The structure is characterised by a full length α-helical conformation between residues F 6 and A 28 . This structural information could play an important role in the design of therapeutic agents based upon GIP receptor agonists

Assessment for markers of nephropathy in newly diagnosed type 2 ...

African Journals Online (AJOL)

Objective: To assess for markers of nephropathy in newly diagnosed type 2 diabetics, using blood pressure levels, endogenous creatinine clearance and urinary protein excretion as markers of renal disease. Study design: Ninety newly diagnosed type 2 diabetics were studied within 6 weeks of diagnosis. They were in ...

Liver fatty acid binding protein is the mitosis-associated polypeptide target of a carcinogen in rat hepatocytes

International Nuclear Information System (INIS)

Bassuk, J.A.; Tsichlis, P.N.; Sorof, S.

1987-01-01

Hepatocytes in normal rat liver were found previously to contain a cytoplasmic 14,000-dalton polypeptide (p14) that is associated with mitosis and is the principal early covalent target of activated metabolites of the carcinogen N-2-fluorenylacetamide (2-acetylaminofluorene). The level of immunohistochemically detected p14 was low when growth activity of hepatocytes was low, was markedly elevated during mitosis in normal and regenerating livers, but was very high throughout interphase during proliferation of hyperplastic and malignant hepatocytes induced in rat liver by a carcinogen (N-2-fluorenylacetamide or 3'-methyl-4-dimethylaminoazobenzene). The authors report here that p14 is the liver fatty acid binding protein. The nucleotide sequence of p14 cDNA clones, isolated by screening a rat liver cDNA library in bacteriophage λgt11 using p14 antiserum, was completely identical to part of the sequence reported for liver fatty acid binding protein. Furthermore, the two proteins shared the following properties: size of mRNA, amino acid composition, molecular size according to NaDodSO 4 gel electrophoresis, and electrophoretic mobilities in a Triton X-100/acetic acid/urea gel. The two polypeptides bound oleic acid similarly. Finally, identical elevations of cytoplasmic immunostain were detected specifically in mitotic hepatocytes with either antiserum. The collected findings are suggestive that liver fatty acid binding protein may carry ligands that promote hepatocyte division and may transport certain activated chemical carcinogens

Effect of zinc oxide nanoparticles synthesized by a precipitation

Indian Academy of Sciences (India)

ZnO nanoparticles were synthesized by a precipitation method in aqueous media from zinc nitrate hexahydrate and sodium hydroxide. The synthesized ZnO nanoparticles exhibited a crystalline structure with hexagonal structure of the wurtzite. The morphology of the synthesized ZnO nanoparticles presented a spherical ...

Nucleophilic behavior of lysine-501 of the alpha-polypeptide of sodium and potassium ion activated adenosinetriphosphatase consistent with a role in binding adenosine triphosphate

International Nuclear Information System (INIS)

Xu, K.Y.; Kyte, J.

1989-01-01

An immunoadsorbent specific for the carboxy-terminal sequence -GAPER, which comprises residues 502-506 of the alpha-polypeptide of ovine sodium and potassium ion activated adenosinetriphosphatase [(Na+ + K+)-ATPase], was used to isolate the products of the reaction between the lysine immediately preceding this sequence in the intact protein and either [3H]acetic anhydride or fluorescein 5'-isothiocyanate. Changes in the apparent nucleophilicity of this lysine, Lys501, were observed with both reagents when ATP was bound by the intact, native enzyme poised in the E1 conformation or when the structure of the enzyme was changed from the E1 conformation into the E2-P conformation. With both reagents, a decrease of more than 4-fold in the yield of incorporation occurred during the former change, but a decrease of only 2-fold occurred during the latter. Because a much larger decrease occurred when ATP was bound in the absence of a conformational change than occurred when a major conformational change took place in the absence of the occupation of the active site, these changes in the incorporation of [3H]acetyl suggest that Lys501 from the alpha polypeptide is directly involved in binding ATP within the active site of (Na+ + K+)-ATPase. The immunochemical reactions between the specific polyclonal antibodies raised against the sequence-GAPER and denatured or enzymically active (Na+ + K+)-ATPase were also investigated. Western blots and the inhibition of enzymic activity caused by the antibody have shown that it can bind to both the denatured and the native form of the alpha-polypeptide, respectively

Probing polypeptide GalNAc-transferase isoform substrate specificities by in vitro analysis

DEFF Research Database (Denmark)

Kong, Yun; Joshi, Hiren J; Schjoldager, Katrine Ter-Borch Gram

2015-01-01

N-acetylgalactosaminyltransferase (GalNAc)-type (mucin-type) O-glycosylation is an abundant and highly diverse modification of proteins. This type of O-glycosylation is initiated in the Golgi by a large family of up to 20 homologous polypeptide GalNAc-T isoenzymes that transfer GalNAc to Ser, Thr...... and possibly Tyr residues. These GalNAc residues are then further elongated by a large set of glycosyltransferases to build a variety of complex O-glycan structures. What determines O-glycan site occupancy is still poorly understood, although it is clear that the substrate specificities of individual...... isoenzymes and the repertoire of GalNAc-Ts in cells are key parameters. The GalNAc-T isoenzymes are differentially expressed in cells and tissues in principle allowing cells to produce unique O-glycoproteomes dependent on the specific subset of isoforms present. In vitro analysis of acceptor peptide...

14 CFR 26.39 - Newly produced airplanes: Fuel tank flammability.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Newly produced airplanes: Fuel tank... Tank Flammability § 26.39 Newly produced airplanes: Fuel tank flammability. (a) Applicability: This... Series 767 Series (b) Any fuel tank meeting all of the criteria stated in paragraphs (b)(1), (b)(2) and...

Possible cleavage sites of glutelin partial degradation confirmed by immunological analysis in globulin-less mutants of rice (Oryza sativa L.).

Science.gov (United States)

Khan, Nadar; Yamaguchi, Satoru; Katsube-Tanaka, Tomoyuki

2017-10-01

Proteolytic cleavage or partial degradation of proteins is one of the important post-translational modifications for various biological processes, but it is difficult to analyze. Previously, we demonstrated that some subunits of the major rice (Oryza sativa L.) seed storage protein glutelin are partially degraded to produce newly identified polypeptides X1-X5 in mutants in which another major seed storage protein globulin is absent. In this study, the new polypeptides X3 and X4/X5 were immunologically confirmed to be derived from GluA3 and GluA1/GluA2 subunits, respectively. Additionally, the new polypeptides X1 and X2 were at least in part the α polypeptides of the GluB4 subunit partially degraded at the C-terminus. Simulated 2D-PAGE migration patterns of intact and partially degraded α polypeptides based on the calculation of their MWs and pIs enabled us to narrow or predict the possible locations of cleavage sites. The predicted cleavage sites were also verified by the comparison of 2D-PAGE patterns between seed-extracted and E. coli-expressed proteins of the intact and truncated α polypeptides. The results and methodologies demonstrated here would be useful for analyses of partial degradation of proteins and the structure-function relationships of rice seed protein bodies. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The dipeptidyl peptidase 4 inhibitor vildagliptin does not accentuate glibenclamide-induced hypoglycemia but reduces glucose-induced glucagon-like peptide 1 and gastric inhibitory polypeptide secretion

DEFF Research Database (Denmark)

El-Ouaghlidi, Andrea; Rehring, Erika; Holst, Jens Juul

2007-01-01

BACKGROUND/AIMS: Inhibition of dipeptidyl peptidase 4 by vildagliptin enhances the concentrations of the active form of the incretin hormones glucagon-like peptide 1 (GLP-1) and gastric inhibitory polypeptide (GIP). The present study asked whether vildagliptin accentuates glibenclamide-induced hy...

Characterization of ppGalNAc-T18, a member of the vertebrate-specific Y subfamily of UDP-N-acetyl-α-D-galactosamine:polypeptide N-acetylgalactosaminyltransferases.

Science.gov (United States)

Li, Xing; Wang, Jing; Li, Wei; Xu, Yingjiao; Shao, Dong; Xie, Yinyin; Xie, Wenxian; Kubota, Tomomi; Narimatsu, Hisashi; Zhang, Yan

2012-05-01

The first step of mucin-type O-glycosylation is catalyzed by members of the UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase (ppGalNAc-T; EC 2.4.1.41) family. Each member of this family has unique substrate specificity and expression profiles. In this report, we describe a new subfamily of ppGalNAc-Ts, designated the Y subfamily. The Y subfamily consists of four members, ppGalNAc-T8, -T9, -T17 and -T18, in which the conserved YDX(5)WGGENXE sequence in the Gal/GalNAc-T motif of ppGalNAc-Ts is mutated to LDX(5)YGGENXE. Phylogenetic analysis revealed that the Y subfamily members only exist in vertebrates. All four Y subfamily members lack in vitro GalNAc-transferase activity toward classical substrates possibly because of the UDP-GalNAc-binding pocket mutants. However, ppGalNAc-T18, the newly identified defining member, was localized in the endoplasmic reticulum rather than the Golgi apparatus in lung carcinoma cells. The knockdown of ppGalNAc-T18 altered cell morphology, proliferation potential and changed cell O-glycosylation. ppGalNAc-T18 can also modulate the in vitro GalNAc-transferase activity of ppGalNAc-T2 and -T10, suggesting that it may be a chaperone-like protein. These findings suggest that the new Y subfamily of ppGalNAc-Ts plays an important role in protein glycosylation; characterizing their functions will provide new insight into the role of ppGalNAc-Ts.

Chrysosplenium japonicum (Saxifragaceae, Newly Recorded from Taiwan

Directory of Open Access Journals (Sweden)

Tian-Chuan Hsu

2011-11-01

Full Text Available Chrysosplenium japonicum (Maxim. Makino (Saxifragaceae is newly recorded from northeastern Taiwan. Description, color photos and a key to the Chrysosplenium species in Taiwan are provided.

Nuclear protein synthesis in animal and vegetal hemispheres of Xenopus oocytes

International Nuclear Information System (INIS)

Feldherr, C.M.; Hodges, P.; Paine, P.L.

1988-01-01

Experiments were conducted to determine if nuclear proteins are preferentially synthesized in the vicinity of the nucleus, a factor which could facilitate nucleocytoplasmic exchange. Using Xenopus oocytes, animal and vegetal hemispheres were separated by bisecting the cells in paraffin oil. It was initially established that protein synthesis is not affected by the bisecting procedure. To determine if nuclear protein synthesis is restricted to the animal hemisphere (which contains the nucleus), vegetal halves and enucleated animal halves were injected with [ 3 H]leucine and incubated in oil for 90 min. The labeled cell halves were then fused with unlabeled, nucleated animal hemispheres that had been previously injected with puromycin in amounts sufficient to prevent further protein synthesis. Thus, labeled polypeptides which subsequently entered the nuclei were synthesized before fusion. Three hours after fusion, the nuclei were isolated, run on two-dimensional gels, and fluorographed. Approximately 200 labeled nuclear polypeptides were compared, and only 2 were synthesized in significantly different amounts in the animal and vegetal hemispheres. The results indicate that nuclear protein synthesis is not restricted to the cytoplasm adjacent to the nucleus

Thermal Synthesis of Polypeptides from N-Butyloxycarbonyl Oligopeptides Containing Aspartyl Residue at C-Terminus

Directory of Open Access Journals (Sweden)

Toratane Munegumi

2017-01-01

Full Text Available The thermal reactions of amino acids have been investigated for pure organic synthesis, materials preparation in industry, and prebiotic chemistry. N-t-Butyloxycarbonyl aspartic acid (Boc-Asp releases 2-butene and carbon dioxide upon heating without solvents. The resulting mixture of the free molten aspartic acid was dehydrated to give peptide bonds. This study describes the thermal reactions of N-t-butyloxycarbonyl peptides (Boc-Gly-L-Asp, Boc-L-Ala-L-Asp, Boc-L-Val-L-Asp, and Boc-Gly-Gly-L-Asp having an aspartic residue at the carboxyl terminus. The peptides were deprotected upon heating at a constant temperature between 110 and 170°C for 1 to 24 h to afford polypeptides in which the average molecular weight reached 7800.

Being a team leader: newly registered nurses relate their experiences.

Science.gov (United States)

Ekström, Louise; Idvall, Ewa

2015-01-01

This paper presents a study that explores how newly qualified registered nurses experience their leadership role in the ward-based nursing care team. A nurse's clinical leadership affects the quality of care provided. Newly qualified nurses experience difficulties during the transition period from student to qualified professional and find it challenging to lead nursing care. Twelve nurses were interviewed and the transcribed texts analysed using qualitative content analysis to assess both manifest and latent content. Five themes were identified: feeling stranded; forming well-functioning teams; learning to lead; having the courage, strength, and desire to lead; and ensuring appropriate care. The findings indicate that many factors limit nurses' leadership but some circumstances are supportive. The leadership prerequisites for newly registered nurses need to improve, emphasizing different ways to create a supportive atmosphere that promotes professional development and job satisfaction. To increase nurse retention and promote quality of care, nurse managers need to clarify expectations and guide and support newly qualified nurses in a planned way. © 2013 John Wiley & Sons Ltd.

Photoaffinity Labeling of Developing Jojoba Seed Microsomal Membranes with a Photoreactive Analog of Acyl-Coenzyme A (Acyl-CoA) (Identification of a Putative Acyl-CoA:Fatty Alcohol Acyltransferase.

Science.gov (United States)

Shockey, J. M.; Rajasekharan, R.; Kemp, J. D.

1995-01-01

Jojoba (Simmondsia chinensis, Link) is the only plant known that synthesizes liquid wax. The final step in liquid wax biosynthesis is catalyzed by an integral membrane enzyme, fatty acyl-coenzyme A (CoA):fatty alcohol acyltransferase, which transfers an acyl chain from acyl-CoA to a fatty alcohol to form the wax ester. To purify the acyltransferase, we have labeled the enzyme with a radioiodinated, photoreactive analog of acyl-CoA, 12-[N-(4-azidosalicyl)amino] dodecanoyl-CoA (ASD-CoA). This molecule acts as an inhibitor of acyltransferase activity in the dark and as an irreversible inhibitor upon exposure to ultraviolet light. Oleoyl-CoA protects enzymatic activity in a concentration-dependent manner. Photolysis of microsomal membranes with labeled ASD-CoA resulted in strong labeling of two polypeptides of 57 and 52 kD. Increasing concentrations of oleoyl-CoA reduced the labeling of the 57-kD polypeptide dramatically, whereas the labeling of the 52-kD polypeptide was much less responsive to oleoyl-CoA. Also, unlike the other polypeptide, the labeling of the 57-kD polypeptide was enhanced considerably when photolyzed in the presence of dodecanol. These results suggest that a 57-kD polypeptide from jojoba microsomes may be the acyl-CoA:fatty alcohol acyltransferase.

People newly in love are more responsive to positive feedback.

Science.gov (United States)

Brown, Cassandra L; Beninger, Richard J

2012-06-01

Passionate love is associated with increased activity in dopamine-rich regions of the brain. Increased dopamine in these regions is associated with a greater tendency to learn from reward in trial-and-error learning tasks. This study examined the prediction that individuals who were newly in love would be better at responding to reward (positive feedback). In test trials, people who were newly in love selected positive outcomes significantly more often than their single (not in love) counterparts but were no better at the task overall. This suggests that people who are newly in love show a bias toward responding to positive feedback, which may reflect a general bias towards reward-seeking.

β-Hairpin of Islet Amyloid Polypeptide Bound to an Aggregation Inhibitor

Science.gov (United States)

Mirecka, Ewa A.; Feuerstein, Sophie; Gremer, Lothar; Schröder, Gunnar F.; Stoldt, Matthias; Willbold, Dieter; Hoyer, Wolfgang

2016-01-01

In type 2 diabetes, the formation of islet amyloid consisting of islet amyloid polypeptide (IAPP) is associated with reduction in β-cell mass and contributes to the failure of islet cell transplantation. Rational design of inhibitors of IAPP amyloid formation has therapeutic potential, but is hampered by the lack of structural information on inhibitor complexes of the conformationally flexible, aggregation-prone IAPP. Here we characterize a β-hairpin conformation of IAPP in complex with the engineered binding protein β-wrapin HI18. The β-strands correspond to two amyloidogenic motifs, 12-LANFLVH-18 and 22-NFGAILS-28, which are connected by a turn established around Ser-20. Besides backbone hydrogen bonding, the IAPP:HI18 interaction surface is dominated by non-polar contacts involving hydrophobic side chains of the IAPP β-strands. Apart from monomers, HI18 binds oligomers and fibrils and inhibits IAPP aggregation and toxicity at low substoichiometric concentrations. The IAPP β-hairpin can serve as a molecular recognition motif enabling control of IAPP aggregation. PMID:27641459

Multiscale characterization of a chimeric biomimetic polypeptide for stem cell culture

International Nuclear Information System (INIS)

Sbrana, F; Vassalli, M; Fotia, C; Baldini, N; Ciapetti, G; Bracalello, A; Bochicchio, B; Marletta, G

2012-01-01

Mesenchymal stem cells have attracted great interest in the field of tissue engineering and regenerative medicine because of their multipotentiality and relative ease of isolation from adult tissues. The medical application of this cellular system requires the inclusion in a growth and delivery scaffold that is crucial for the clinical effectiveness of the therapy. In particular, the ideal scaffolding material should have the needed porosity and mechanical strength to allow a good integration with the surrounding tissues, but it should also assure high biocompatibility and full resorbability. For such a purpose, protein-inspired biomaterials and, in particular, elastomeric-derived polypeptides are playing a major role, in which they are expected to fulfil many of the biological and mechanical requirements. A specific chimeric protein, designed starting from elastin, resilin and collagen sequences, was characterized over different length scales. Single-molecule mechanics, aggregation properties and compatibility with human mesenchymal stem cells were tested, showing that the engineered compound is a good candidate as a stem cell scaffold to be used in tissue engineering applications. (paper)

Thermoluminescence properties of Li2B4O7:Cu, B phosphor synthesized using solution combustion technique

International Nuclear Information System (INIS)

Ozdemir, A.; Altunal, V.; Kurt, K.; Depci, T.; Yu, Y.; Lawrence, Y.; Nur, N.; Guckan, V.; Yegingil, Z.

2017-01-01

To determine the effects of various concentrations of the activators copper (Cu) and boron (B) on the thermoluminescence (TL) properties of lithium tetraborate, the phosphor was first synthesized and doped with five different concentrations of copper (0.1–0.005 wt%) using solution combustion method. 0.01 wt% Cu was the concentration which showed the most significant increase in the sensitivity of the phosphor. The second sort of Li 2 B 4 O 7 :Cu material was prepared by adding B (0.001–0.03 wt%) to it. The newly developed copper-boron activated lithium tetraborate (Li 2 B 4 O 7 :Cu, B) material with 0.01 wt% Cu and 0.001 wt% B impurity concentrations was shown to have promise as a TL phosphor. The material formation was examined using powder x-Ray Diffraction (XRD) analysis and Scanning Electron Microscope (SEM) imaging. Fourier Transform Infrared (FT-IR) spectrum of the synthesized polycrystalline powder sample was also recorded. The TL glow curves were analyzed to determine various dosimetric characteristics of the synthesized luminophosphors. The dose response increased in a “linear” way with the beta-ray exposure between 0.1–20 Gy, a dose range being interested in medical dosimetry. The response with changing photon and electron energy was studied. The rate of decay of the TL signal was investigated both for dark storage and under direct sunlight. Li 2 B 4 O 7 :Cu, B showed no individual variation of response in 9 recycling measurements. The fluorescence spectrum was determined. The kinetic parameters were estimated by different methods and the results discussed. The studied properties of synthesized Li 2 B 4 O 7 :Cu, B were found all favorable for dosimetric purposes. - Highlights: • Li 2 B 4 O 7 :Cu, B synthesis using solution combustion method with various concentrations. • Structure analysis of Li 2 B 4 O 7 :Cu, B using XRD, SEM and FTIR methods. • Investigation of thermoluminescent properties of Li 2 B 4 O 7 :Cu, B. • Relatively good

Workplace Violence and Job Outcomes of Newly Licensed Nurses

OpenAIRE

Chang, Hyoung Eun; Cho, Sung-Hyun

2016-01-01

Purpose: The purpose of this study was to examine the prevalence of workplace violence toward newly licensed nurses and the relationship between workplace violence and job outcomes. Methods: An online survey was conducted of newly licensed registered nurses who had obtained their license in 2012 or 2013 in South Korea and had been working for 5–12 months after first being employed. The sample consisted of 312 nurses working in hospitals or clinics. The Copenhagen Psychosocial Questionnaire...

Breakout character of islet amyloid polypeptide hydrophobic mutations at the onset of type-2 diabetes

Science.gov (United States)

Frigori, Rafael B.

2014-11-01

Toxic fibrillar aggregates of islet amyloid polypeptide (IAPP) appear as the physical outcome of a peptidic phase transition signaling the onset of type-2 diabetes mellitus in different mammalian species. In particular, experimentally verified mutations on the amyloidogenic segment 20-29 in humans, cats, and rats are highly correlated with the molecular aggregation propensities. Through a microcanonical analysis of the aggregation of IAPP20 -29 isoforms, we show that a minimalist one-bead hydrophobic-polar continuum model for protein interactions properly quantifies those propensities from free-energy barriers. Our results highlight the central role of sequence-dependent hydrophobic mutations on hot spots for stabilization, and thus for the engineering, of such biological peptides.

Cleavage sites in the polypeptide precursors of poliovirus protein P2-X

International Nuclear Information System (INIS)

Selmer, B.L.; Hanecak, R.; Anderson, C.W.; Wimmer, E.

1981-01-01

Partial amino-terminal sequence analysis has been performed on the three major polypeptide products (P2-3b, P2-5b, and P2-X) from the central region (P2) of the poliovirus polyprotein, and this analysis precisely locates the amino termini of these products with respect to the nucleotide sequence of the poliovirus RNA genome. Like most of the products of the replicase region (P3), the amino termini of P2-5b and P2-X are generated by cleavage between glutamine and glycine residues. Thus, P2-5b and P2-X are probably both produced by the action of a singly (virus-encoded.) proteinase. The amino terminus of P2-3b, on the other hand, is produced by a cleavage between the carboxy-terminal tyrosine of VP1 and the glycine encoded by nucleotides 3381-3383. This result may suggest that more than one proteolytic activity is required for the complete processing of the poliovirus polyprotein

Enantioselective catalytic syntheses of alpha-branched chiral amines

DEFF Research Database (Denmark)

Brase, S.; Baumann, T.; Dahmen, S.

2007-01-01

Chiral amines play a pivotal role in fine chemical and natural product syntheses and the design of novel materials.......Chiral amines play a pivotal role in fine chemical and natural product syntheses and the design of novel materials....

In vitro Anti-Leishmania Activity and Safety of Newly Synthesized ...

African Journals Online (AJOL)

International Pharmaceutical Abstract, Chemical Abstracts, Embase, Index Copernicus, EBSCO, African. Index Medicus, JournalSeek ... virus (HAV), serotonin 5-HT6 receptor antagonist ..... Structure-activity relationships based on the obtained ...

Acute toxicity and gastroprotection studies with a newly synthesized steroid.

Science.gov (United States)

Ketuly, Kamal A; Hadi, A Hamid A; Golbabapour, Shahram; Hajrezaie, Maryam; Hassandarvish, Pouya; Ali, Hapipah Mohd; Abdul Majid, Nazia; Abdulla, Mahmood A

2013-01-01

Synthetic steroids, such as 9α-bromobeclomethasonedipropionate, have shown gastroprotective activity. For example, the potent glucocorticoid steroid, beclomethasone dipropionate, has been used for treatment of bowel ulcerations. The purpose of the present study was to evaluate the effect of a synthetic steroid, (20S)-22-acetoxymethyl-6β-methoxy-3α,5-dihydro-3'H-cyclopropa[3α,5]-5α-pregnane (AMDCP), on ethanol-induced gastric mucosa injuries in rats. Rats were divided into 8 groups. The negative control and ethanol control groups were administered Tween 20 (10%v/v) orally. The reference control group, 20 mg/kg omeprazole (10% Tween 20, 5 mL/kg), was administrated orally. The experimental groups received 1, 5, 10, 15 or 20 mg/kg of the AMDCP compound (10% Tween 20, 5 mL/kg). After 60 min, Tween 20 and absolute ethanol was given orally (5 mL/kg) to the negative control group and to the rest of the groups, and the rats were sacrificed an hour later. The acidity of gastric content, gastric wall mucus and areas of mucosal lesions were assessed. In addition, histology and immunohistochemistry of the gastric wall were assessed. Prostaglandin E2 (PGE2) and malondialdehyde (MDA) content were also measured. The ethanol control group exhibited severe mucosal lesion compared with the experimental groups with fewer mucosal lesions along with a reduction of edema and leukocyte infiltration. Immunohistochemical staining of Hsp70 and Bax proteins showed over-expression and under-expression, respectively, in the experimental groups. The experimental groups also exhibited high levels of PGE2 as well as a reduced amount of MDA. AMDCP decreased the acidity and lipid peroxidation and increased the levels of antioxidant enzymes. The current investigation evaluated the gastroprotective effects of AMDCP on ethanol-induced gastric mucosal lesions in rats. This study also suggests that AMDCP might be useful as a gastroprotective agent.

Spectroelectrochemical and electrochromic behaviors of newly synthesized poly[3′-(2-aminopyrimidyl)-2,2′:5′,2″-terthiophene

International Nuclear Information System (INIS)

Kim, Dong-Min; Shim, Kyu-Bin; Son, Jung Ik; Reddy, Sanapalli S.; Shim, Yoon-Bo

2013-01-01

The functionalized conductive polymer precursor of the terthiophene derivative, 3′-(2-aminopyrimidyl)-2,2′:5′,2″-terthiophene (PATT) was firstly synthesized and confirmed with FT-IR, 1 H NMR, 13 C NMR, and mass spectroscopy. The electrochemical and electronic properties of polyPATT film are investigated and compared with that of poly(2,2′:5′,2″-terthiophene-3′-p-benzoic acid) (polyTTBA), which has an electron-accepting group. The cyclic voltammograms (CVs) recorded for electrochemically grown polyPATT reveal the redox peaks at +1.1/+0.96 V, and the conductivity increases monotonically as the applying potential goes to the positive direction (0.11 S cm −1 at +1.4 V). The spectroelectrochemical analysis of polyPATT reveals the absorption bands at 456, 825 and 643 nm corresponding to the π–π* transition, polaron, and bipolaron formations, respectively. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of the polyPATT film bearing an electron donating group are to be 3.60 and 5.54 eV, respectively. The polyPATT film shows reversible multiple color transition within 0.6 s (from brownish-yellow (at 0.0 V) to blue (at +1.4 V)) when the potential switches between the reduced and oxidized states

Syntheses and modulations in the chromatin contents of histones H1/sup o/ and H1 during G1 and S phases in Chinese hamsters cells

International Nuclear Information System (INIS)

D'Anna, J.A.; Gurley, L.R.; Tobey, R.A.

1982-01-01

Flow cytometry, conventional autoradiography, and autoradiography employing high concentrations of high specific activity [ 3 H]thymidine indicate that (1) treatment of Chinese hamster ovary (line CHO) cells with butyrate truly blocks cells in G 1 and (2) cells blocked in G 1 by isoleucine deprivation remain blocked in G 1 when they are released into complete medium containing butyrate. Measurements of H1/sup o/ content relative to core histones and H1/sup o/:H1 ratios indicate that H1/sup o/ is enhanced somewhat in G 1 cells arrested by isoleucine deprivation; however, (1) treatment with butyrate greatly increases the H1/sup o/ content in G 1 -blocked cells, and (2) the enhancement is very sensitive to butyrate concentration. Measurements of relative histone contents in the isolated chromatin of synchronized cultures also suggest that the acid-soluble content of histone H1 (relative to core histones) becomes greatly depleted in the isolated chromatin when synchronized cells are blocked in early S phase by sequential use of isoleucine deprivation and hydroxyurea blockade. We also have measured [ 3 H]lysine incorporation, various protein ratios, and relative rates of deposition of newly synthesized H1/sup o/, H1, and H4 onto chromatin during G 1 and S in the absence of butyrate. The results suggest a dynamic picture of chromatin organization in which (1) newly synthesized histone H1/sup o/ binds to chromatin during traverse of G 1 and S phases and (2) histone H1 dissociates from (or becomes loosely bound to) chromatin during prolonged early S-phase block with hydroxyurea

Aeon: Synthesizing Scheduling Algorithms from High-Level Models

Science.gov (United States)

Monette, Jean-Noël; Deville, Yves; van Hentenryck, Pascal

This paper describes the aeon system whose aim is to synthesize scheduling algorithms from high-level models. A eon, which is entirely written in comet, receives as input a high-level model for a scheduling application which is then analyzed to generate a dedicated scheduling algorithm exploiting the structure of the model. A eon provides a variety of synthesizers for generating complete or heuristic algorithms. Moreover, synthesizers are compositional, making it possible to generate complex hybrid algorithms naturally. Preliminary experimental results indicate that this approach may be competitive with state-of-the-art search algorithms.

The development of [18F]FDG synthesizer

International Nuclear Information System (INIS)

Hu, M. G.; Kim, S. W.; Lee, J. Y.; Yang, S. D.; Jun, G. S.

2003-01-01

The automatic system for [ 18 F]FDG production using for the diagnosis of cancer has been developed. This automation system was consisted of a synthesizer module, a PLC based controller and a PMU for graphic user interface. By this system, the radiochemical purity was over 98%, the production yield was over 30% after synthesize and elapsed time was 35 minute

Oxidative stress status, antioxidant metabolism and polypeptide patterns in Juncus maritimus shoots exhibiting differential mercury burdens in Ria de Aveiro coastal lagoon (Portugal).

Science.gov (United States)

Anjum, Naser A; Duarte, Armando C; Pereira, Eduarda; Ahmad, Iqbal

2014-05-01

This study assessed the oxidative stress status, antioxidant metabolism and polypeptide patterns in salt marsh macrophyte Juncus maritimus shoots exhibiting differential mercury burdens in Ria de Aveiro coastal lagoon at reference and the sites with highest, moderate and the lowest mercury contamination. In order to achieve these goals, shoot-mercury burden and the responses of representative oxidative stress indices, and the components of both non-glutathione- and glutathione-based H2O2-metabolizing systems were analyzed and cross-talked with shoot-polypeptide patterns. Compared to the reference site, significant elevations in J. maritimus shoot mercury and the oxidative stress indices such as H2O2, lipid peroxidation, electrolyte leakage and reactive carbonyls were maximum at the site with highest followed by moderate and the lowest mercury contamination. Significantly elevated activity of non-glutathione-based H2O2-metabolizing enzymes such as ascorbate peroxidase and catalase accompanied the studied damage-endpoint responses, whereas the activity of glutathione-based H2O2-scavenging enzymes glutathione peroxidase and glutathione sulfo-transferase was inhibited. Concomitantly, significantly enhanced glutathione reductase activity and the contents of both reduced and oxidized glutathione were perceptible in high mercury-exhibiting shoots. It is inferred that high mercury-accrued elevations in oxidative stress indices were obvious, where non-glutathione-based H2O2-decomposing enzyme system was dominant over the glutathione-based H2O2-scavenging enzyme system. In particular, the glutathione-based H2O2-scavenging system failed to coordinate with elevated glutathione reductase which in turn resulted into increased pool of oxidized glutathione and the ratio of oxidized glutathione-to-reduced glutathione. The substantiation of the studied oxidative stress indices and antioxidant metabolism with approximately 53-kDa polypeptide warrants further studies.

Intestinal mucosa is a target tissue for pancreatic polypeptide

International Nuclear Information System (INIS)

Gilbert, W.R.; Kramer, J.L.; Frank, B.H.; Gingerich, R.L.

1986-01-01

Studies were carried out to identify mammalian tissues capable of specifically binding mammalian pancreatic polypeptide (PP). Bovine PP (bPP) radiolabeled with 125 I was purified by HPLC to yield [ 125 I]iodo-(Tyr-27) bPP. The label was injected into three pairs of fasted littermate dogs and allowed to circulate for 5 min. One of the dogs was a control which received an excess of unlabeled porcine PP to provide competition for receptor binding. Unbound bPP was removed by perfusion with Krebs-Ringer bicarbonate and the tissue fixed in situ with Karnovsky's fixative. Tissue samples from various organs were removed, weighed, and counted. The entire gastrointestinal tract demonstrated high levels of 125 I after injection of the labeled peptide. The duodenum, jejunum, ileum, and colon were the only tissues to exhibit specific binding of bPP. These tissues (mucosal and muscle layers) from experimental animals exhibited 31-76% higher binding than the corresponding tissues from the control animals. Sections of the gastrointestinal tract were scraped to separate the mucosal layer from the underlying muscle layer. The mucosal layer of the duodenum, jejunum, and ileum exhibited 145-162% increases in binding compared to the control animals. The muscle layer of these tissues demonstrated no significant increase. These findings demonstrate that mucosal layer of the small intestine is a target tissue for mammalian PP

DNA-interactive properties of crotamine, a cell-penetrating polypeptide and a potential drug carrier.

Directory of Open Access Journals (Sweden)

Pei-Chun Chen

Full Text Available Crotamine, a 42-residue polypeptide derived from the venom of the South American rattlesnake Crotalus durissus terrificus, has been shown to be a cell-penetrating protein that targets chromosomes, carries plasmid DNA into cells, and shows specificity for actively proliferating cells. Given this potential role as a nucleic acid-delivery vector, we have studied in detail the binding of crotamine to single- and double-stranded DNAs of different lengths and base compositions over a range of ionic conditions. Agarose gel electrophoresis and ultraviolet spectrophotometry analysis indicate that complexes of crotamine with long-chain DNAs readily aggregate and precipitate at low ionic strength. This aggregation, which may be important for cellular uptake of DNA, becomes less likely with shorter chain length. 25-mer oligonucleotides do not show any evidence of such aggregation, permitting the determination of affinities and size via fluorescence quenching experiments. The polypeptide binds non-cooperatively to DNA, covering about 5 nucleotide residues when it binds to single (ss or (ds double stranded molecules. The affinities of the protein for ss- vs. ds-DNA are comparable, and inversely proportional to salt levels. Analysis of the dependence of affinity on [NaCl] indicates that there are a maximum of ∼3 ionic interactions between the protein and DNA, with some of the binding affinity attributable to non-ionic interactions. Inspection of the three-dimensional structure of the protein suggests that residues 31 to 35, Arg-Trp-Arg-Trp-Lys, could serve as a potential DNA-binding site. A hexapeptide containing this sequence displayed a lower DNA binding affinity and salt dependence as compared to the full-length protein, likely indicative of a more suitable 3D structure and the presence of accessory binding sites in the native crotamine. Taken together, the data presented here describing crotamine-DNA interactions may lend support to the design of more

Effects of gastric inhibitory polypeptide, glucagon-like peptide-1 and glucagon-like peptide-1 receptor agonists on Bone Cell Metabolism

DEFF Research Database (Denmark)

Hansen, Morten S S; Tencerova, Michaela; Frølich, Jacob

2018-01-01

The relationship between gut and skeleton is increasingly recognised as part of the integrated physiology of the whole organism. The incretin hormones gastric inhibitory polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are secreted from the intestine in response to nutrient intake and exhibi......-clinical investigations, clinical trials are needed to clarify if similar effects are present and clinically relevant in humans. This article is protected by copyright. All rights reserved....

Exercise recommendations in patients with newly diagnosed fibromyalgia.

Science.gov (United States)

Wilson, Brad; Spencer, Horace; Kortebein, Patrick

2012-04-01

To evaluate exercise recommendations in patients newly diagnosed with fibromyalgia. A retrospective chart review. A public university rheumatology clinic. Patients newly diagnosed with fibromyalgia (N = 122). Frequency and type of exercise recommendations. The mean (standard deviation) age of these patients with fibromyalgia was 45 ± 12 years; 91% were women. Exercise was recommended as part of the documented treatment plan in 47% of these patients (57/122); only 3 patients had a documented contraindication for exercise. Aquatic exercise was most frequently recommended (56% [32/57]), followed by combined aquatic-aerobic exercise (26% [15/57]), and, infrequently, aerobic exercise only (5% [3/57]); only 7% of these patients (4/57) were referred for physical therapy. The primary method of communication was verbal discussion (94% [54/57]). Although there is well-documented evidence that exercise is beneficial for patients with fibromyalgia, we found that less than half of patients with newly diagnosed fibromyalgia in our study were provided recommendations to initiate an exercise program as part of their treatment plan. Further investigation of these findings are warranted, including evaluation of other university and community rheumatology practices as well as that of other physicians caring for patients with fibromyalgia. However, our findings indicate that there appears to be an opportunity to provide more specific and practical education regarding the implementation of an exercise regimen for patients with newly diagnosed fibromyalgia. Physiatrists may be particularly well suited to manage the exercise component of patients with fibromyalgia because of their specialized training in exercise prescription. Copyright © 2012 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Syntheses and absorption-structure relationships of some new ...

Indian Academy of Sciences (India)

New biheterocyclic compound was synthesized as starting material to prepare new photosensitizers mono-, tri-, substituted tri-, azadimethine and mixed cyanine dyes. Absorption-structure relationship of the synthesized cyanine dyes were determined by studying their electronic spectral behaviour in ethanol. The structure of ...

In silico binding analysis and SAR elucidations of newly designed benzopyrazine analogs as potent inhibitors of thymidine phosphorylase.

Science.gov (United States)

Taha, Muhammad; Ismail, Nor Hadiani; Imran, Syahrul; Rahim, Fazal; Wadood, Abdul; Al Muqarrabun, Laode Muhammad Ramadhan; Khan, Khalid Mohammed; Ghufran, Mehreen; Ali, Muhammad

2016-10-01

Thymidine phosphorylase (TP) is up regulated in wide variety of solid tumors and therefore presents a remarkable target for drug discovery in cancer. A novel class of extremely potent TPase inhibitors based on benzopyrazine (1-28) has been developed and evaluated against thymidine phosphorylase enzyme. Out of these twenty-eight analogs eleven (11) compounds 1, 4, 14, 15, 16, 17, 18, 19, 20, 24 and 28 showed potent thymidine phosphorylase inhibitory potentials with IC50 values ranged between 3.20±0.30 and 37.60±1.15μM when compared with the standard 7-Deazaxanthine (IC50=38.68±4.42μM). Structure-activity relationship was established and molecular docking studies were performed to determine the binding interactions of these newly synthesized compounds. Current studies have revealed that these compounds established stronger hydrogen bonding networks with active site residues as compare to the standard compound 7DX. Copyright © 2016 Elsevier Inc. All rights reserved.

How early studies on secreted and membrane protein quality control gave rise to the ER associated degradation (ERAD) pathway: the early history of ERAD.

Science.gov (United States)

Needham, Patrick G; Brodsky, Jeffrey L

2013-11-01

All newly synthesized proteins are subject to quality control check-points, which prevent aberrant polypeptides from harming the cell. For proteins that ultimately reside in the cytoplasm, components that also reside in the cytoplasm were known for many years to mediate quality control. Early biochemical and genetic data indicated that misfolded proteins were selected by molecular chaperones and then targeted to the proteasome (in eukaryotes) or to proteasome-like particles (in bacteria) for degradation. What was less clear was how secreted and integral membrane proteins, which in eukaryotes enter the endoplasmic reticulum (ER), were subject to quality control decisions. In this review, we highlight early studies that ultimately led to the discovery that secreted and integral membrane proteins also utilize several components that constitute the cytoplasmic quality control machinery. This component of the cellular quality control pathway is known as ER associated degradation, or ERAD. This article is part of a Special Issue entitled: Functional and structural diversity of endoplasmic reticulum. Copyright © 2013 Elsevier B.V. All rights reserved.

Chaperoning Roles of Macromolecules Interacting with Proteins in Vivo

Directory of Open Access Journals (Sweden)

Baik L. Seong

2011-03-01

Full Text Available The principles obtained from studies on molecular chaperones have provided explanations for the assisted protein folding in vivo. However, the majority of proteins can fold without the assistance of the known molecular chaperones, and little attention has been paid to the potential chaperoning roles of other macromolecules. During protein biogenesis and folding, newly synthesized polypeptide chains interact with a variety of macromolecules, including ribosomes, RNAs, cytoskeleton, lipid bilayer, proteolytic system, etc. In general, the hydrophobic interactions between molecular chaperones and their substrates have been widely believed to be mainly responsible for the substrate stabilization against aggregation. Emerging evidence now indicates that other features of macromolecules such as their surface charges, probably resulting in electrostatic repulsions, and steric hindrance, could play a key role in the stabilization of their linked proteins against aggregation. Such stabilizing mechanisms are expected to give new insights into our understanding of the chaperoning functions for de novo protein folding. In this review, we will discuss the possible chaperoning roles of these macromolecules in de novo folding, based on their charge and steric features.

Mucin-type O-glycosylation is controlled by short- and long-range glycopeptide substrate recognition that varies among members of the polypeptide GalNAc transferase family

DEFF Research Database (Denmark)

Revoredo, Leslie; Wang, Shengjun; Bennett, Eric Paul

2016-01-01

A large family of UDP-GalNAc:polypeptide GalNAc transferases (ppGalNAc-Ts) initiates and defines sites of mucin-type Ser/Thr-O-GalNAc glycosylation. Family members have been classified into peptide- and glycopeptide-preferring subfamilies, although both families possess variable activities agains...

Vasoactive intestinal polypeptide and peptide histidine methionine. Presence in human follicular fluid and effects on DNA synthesis and steroid secretion in cultured human granulosa/lutein cells

DEFF Research Database (Denmark)

Gräs, S; Ovesen, Per Glud; Andersen, A N

1994-01-01

Vasoactive intestinal polypeptide (VIP) and peptide histidine methionine (PHM) originate from the same precursor molecule, prepro VIP. In the present study we examined the concentrations of VIP and PHM in human follicular fluid and their effects on cultured human granulosa/lutein cells. Follicula...

Nilotinib versus imatinib for newly diagnosed chronic myeloid leukemia

DEFF Research Database (Denmark)

Saglio, Giuseppe; Kim, Dong-Wook; Issaragrisil, Surapol

2010-01-01

Nilotinib has been shown to be a more potent inhibitor of BCR-ABL than imatinib. We evaluated the efficacy and safety of nilotinib, as compared with imatinib, in patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukemia (CML) in the chronic phase.......Nilotinib has been shown to be a more potent inhibitor of BCR-ABL than imatinib. We evaluated the efficacy and safety of nilotinib, as compared with imatinib, in patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukemia (CML) in the chronic phase....

Transformation of organic N newly added to red soil treated with different cultural practices

Institute of Scientific and Technical Information of China (English)

ZhangQin－Zheng; YeQing－Fu; 等

1998-01-01

By using 15N tracer method,transformation of organic N,which wqas newly added to red soil treated with different cultural practices,was studied under thelaboratory incubation condition.The experimental results showed that the transformation of N from newly added organic matter and soil native pool during incubation was influenced by cultural practice treatment beforeincubation.Fallow was favorable to the mineralization of newly added organic N and soil N compared with the planting wheat treatment.Planting wheat greatly increased the loss of soil N.Application of fertilizers stimulated the mineralization of newly added organic N and application of organic matter reduced the mineralization,but stimulated microbialtransformation of newly adde4d organic N.

Hepatic uptake of conjugated bile acids is mediated by both sodium taurocholate cotransporting polypeptide and organic anion transporting polypeptides and modulated by intestinal sensing of plasma bile acid levels in mice.

Science.gov (United States)

Slijepcevic, Davor; Roscam Abbing, Reinout L P; Katafuchi, Takeshi; Blank, Antje; Donkers, Joanne M; van Hoppe, Stéphanie; de Waart, Dirk R; Tolenaars, Dagmar; van der Meer, Jonathan H M; Wildenberg, Manon; Beuers, Ulrich; Oude Elferink, Ronald P J; Schinkel, Alfred H; van de Graaf, Stan F J

2017-11-01

The Na + -taurocholate cotransporting polypeptide (NTCP/SLC10A1) is believed to be pivotal for hepatic uptake of conjugated bile acids. However, plasma bile acid levels are normal in a subset of NTCP knockout mice and in mice treated with myrcludex B, a specific NTCP inhibitor. Here, we elucidated which transport proteins mediate the hepatic uptake of conjugated bile acids and demonstrated intestinal sensing of elevated bile acid levels in plasma in mice. Mice or healthy volunteers were treated with myrcludex B. Hepatic bile acid uptake kinetics were determined in wild-type (WT), organic anion transporting polypeptide (OATP) knockout mice (lacking Slco1a/1b isoforms), and human OATP1B1-transgenic mice. Effects of fibroblast growth factor 19 (FGF19) on hepatic transporter mRNA levels were assessed in rat hepatoma cells and in mice by peptide injection or adeno-associated virus-mediated overexpression. NTCP inhibition using myrcludex B had only moderate effects on bile acid kinetics in WT mice, but completely inhibited active transport of conjugated bile acid species in OATP knockout mice. Cholesterol 7α-hydroxylase Cyp7a1 expression was strongly down-regulated upon prolonged inhibition of hepatic uptake of conjugated bile acids. Fgf15 (mouse counterpart of FGF19) expression was induced in hypercholanemic OATP and NTCP knockout mice, as well as in myrcludex B-treated cholestatic mice, whereas plasma FGF19 was not induced in humans treated with myrcludex B. Fgf15/FGF19 expression was induced in polarized human enterocyte-models and mouse organoids by basolateral incubation with a high concentration (1 mM) of conjugated bile acids. NTCP and OATPs contribute to hepatic uptake of conjugated bile acids in mice, whereas the predominant uptake in humans is NTCP mediated. Enterocytes sense highly elevated levels of (conjugated) bile acids in the systemic circulation to induce FGF15/19, which modulates hepatic bile acid synthesis and uptake. (Hepatology 2017;66:1631-1643). �

Effect of surfactant and surfactant blends on pseudoternary phase diagram behavior of newly synthesized palm kernel oil esters

Directory of Open Access Journals (Sweden)

Mahdi ES

2011-06-01

Full Text Available Elrashid Saleh Mahdi1, Mohamed HF Sakeena1, Muthanna F Abdulkarim1, Ghassan Z Abdullah1,3, Munavvar Abdul Sattar2, Azmin Mohd Noor11Department of Pharmaceutical Technology, 2Department of Physiology, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia; 3Department of Pharmaceutical Technology, International Medical University, Bukit Jalil, Kuala Lumpur, MalaysiaBackground: The purpose of this study was to select appropriate surfactants or blends of surfactants to study the ternary phase diagram behavior of newly introduced palm kernel oil esters.Methods: Nonionic surfactant blends of Tween® and Tween®/Span® series were screened based on their solubilization capacity with water for palm kernel oil esters. Tween® 80 and five blends of Tween® 80/Span® 80 and Tween® 80/Span® 85 in the hydrophilic-lipophilic balance (HLB value range of 10.7–14.0 were selected to study the phase diagram behavior of palm kernel oil esters using the water titration method at room temperature.Results: High solubilization capacity was obtained by Tween® 80 compared with other surfactants of Tween® series. High HLB blends of Tween® 80/Span® 85 and Tween® 80/Span® 80 at HLB 13.7 and 13.9, respectively, have better solubilization capacity compared with the lower HLB values of Tween® 80/Span® 80. All the selected blends of surfactants were formed as water-in-oil microemulsions, and other dispersion systems varied in size and geometrical layout in the triangles. The high solubilization capacity and larger areas of the water-in-oil microemulsion systems were due to the structural similarity between the lipophilic tail of Tween® 80 and the oleyl group of the palm kernel oil esters.Conclusion: This study suggests that the phase diagram behavior of palm kernel oil esters, water, and nonionic surfactants is not only affected by the HLB value, but also by the structural similarity between palm kernel oil esters and the surfactant

Solid phase syntheses of oligoureas

Energy Technology Data Exchange (ETDEWEB)

Burgess, K.; Linthicum, D.S.; Russell, D.H.; Shin, H.; Shitangkoon, A.; Totani, R.; Zhang, A.J.; Ibarzo, J. [Texas A& M Univ., College Station, TX (United States)

1997-02-19

Isocyanates 7 were formed from monoprotected diamines 3 or 6, which in turn can be easily prepared from commercially available N-BOC- or N-FMOC-protected amino acid derivatives. Isocyanates 7, formed in situ, could be coupled directly to a solid support functionalized with amine groups or to amino acids anchored on resins using CH{sub 2}Cl{sub 2} as solvent and an 11 h coupling time at 25 {degree}C. Such couplings afforded peptidomimetics with an N-phthaloyl group at the N-terminus. The optimal conditions identified for removal of the N-phthaloyl group were to use 60% hydrazine in DMF for 1-3 h. Several sequences of amino acids coupled to ureas (`peptidic ureas`) and of sequential urea units (`oligoureas`) were prepared via solid phase syntheses and isolated by HPLC. Partition coefficients were measured for two of these peptidomimetics, and their water solubilities were found to be similar to the corresponding peptides. A small library of 160 analogues of the YGGFL-amide sequence was prepared via Houghten`s tea bag methodology. This library was tested for binding to the anti-{beta}-endorphin monoclonal antibody. Overall, this paper describes methodology for solid phase syntheses of oligourea derivatives with side chains corresponding to some of the protein amino acids. The chemistry involved is ideal for high-throughput syntheses and screening operations. 51 refs., 3 figs., 2 tabs.

Proteoglycon synthesis by articular chondrocytes in agarose culture

International Nuclear Information System (INIS)

Sweet, M.B.E.; Grisillo, A.; Coehlo, A.; Schnitzler, C.M.

1987-01-01

Articular chondrocytes were isolated from knee joints of full-term bovine foetuses and grown in long-term agarose cultures. At intervals, cultures were labelled with 35 S-[sulphate] or D[6- 3 H] glucosamine. Newly synthesized proteoglycans were extracted with 4 M guanidine HCl and purified by isopycnic density gradient centrifugation or on DEAE cellulose in the presence of 8 M urea. Characterization of the proteoglycans revealed them to be identical in size to those present in the tissue and to be similarly capable of aggregation with hyaluronate. Newly synthesized chondroitin sulphate chains were identical in size, but newly synthesized keratan sulphate chains were somewhat larger than those present in the tissue. The newly synthesized proteoglycans were shown to contain the same range of O-linked oligosaccharides identified in proteoglycans of the Swarm rat chondrosarcoma. Cartilage-specific proteoglycan continued to be synthesized by the chondrocytes for up to 60 days; however, with time, proportionately more of a small non-aggregating proteoglycan appeared

Bovine pancreatic polypeptide as an antagonist of muscarinic cholinergic receptors

International Nuclear Information System (INIS)

Pan, G.Z.; Lu, L.; Qian, J.; Xue, B.G.

1987-01-01

In dispersed acini from rat pancreas, it was found that bovine pancreatic polypeptide (BPP) and its C-fragment hexapeptide amide (PP-6), at concentrations of 0.1 and 30 μM, respectively, could significantly inhibit amylase secretion stimulated by carbachol, and this inhibition by BPP was dose dependent. 45 Ca outflux induced by carbachol was also inhibited by BPP or PP-6, but they had no effect on cholecystokinin octapeptide- (CCK-8) or A23187-stimulated 45 Ca outflux. BPP was also capable of displacing the specific binding of [ 3 H]-quinuclidinyl benzilate to its receptors, and it possessed a higher affinity (K/sub i/35nM) than carbachol (K/sub i/ 1.8 μM) in binding with M-receptors. It is concluded from this study that BPP acts as an antagonist of muscarinic cholinergic receptors in rat pancreatic acini. In addition, BPP inhibited the potentiation of amylase secretion caused by the combination of carbachol plus secretin or vasoactive intestinal peptide. This may be a possible explanation of the inhibitory effect of BPP on secretin-induced pancreatic enzyme secretion shown in vivo, since pancreatic enzyme secretion stimulated by secretin under experimental conditions may be the result of potentiation of enzyme release produced by the peptide in combination with a cholinergic stimulant

Substrate specificities of three members of the human UDP-N-acetyl-alpha-D-galactosamine:Polypeptide N-acetylgalactosaminyltransferase family, GalNAc-T1, -T2, and -T3

DEFF Research Database (Denmark)

Wandall, H H; Hassan, H; Mirgorodskaya, E

1997-01-01

Mucin-type O-glycosylation is initiated by UDP-N-acetylgalactosamine:polypeptide N-acetylgalactosaminyltransferases (GalNAc-transferases). The role each GalNAc-transferase plays in O-glycosylation is unclear. In this report we characterized the specificity and kinetic properties of three purified...

Substitution of conventional high-temperature syntheses of inorganic compounds by near-room-temperature syntheses in ionic liquids

KAUST Repository

Groh, Matthias Friedrich

2013-01-01

The high-temperature syntheses of the low-valent halogenides P2I4, Te2Br, α-Te4I4, Te4(Al2Cl7)2, Te4(Bi6Cl20), Te8(Bi4Cl14),Bi8(AlCl4)2, Bi6Cl7,and Bi6Br7, as well as of WSCl4 andWOCl4 have been replaced by resource-efficient low-temperature syntheses in room temperature ionic liquids (RTILs). The simple one-pot syntheses generally do not require elaborate equipment such as twozone furnaces or evacuated silica ampoules. Compared to the published conventional approaches, reduction of reaction time (up to 80%) and temperature (up to 500 K) and, simultaneously, an increase in yield were achieved. In the majority of cases, the solid products were phase-pure. X-Ray diffraction on single crystals (redetermination of 11 crystal structures) has demonstrated that the quality of the crystals from RTILs is comparable to that of products obtained by chemical transport reactions. © 2013 Verlag der Zeitschrift für Naturforschung, Tübingen.

Investigation of formation constant of complex of a new synthesized tripodal ligand with Cu2+ using rank annihilation factor analysis in surfactant media

Directory of Open Access Journals (Sweden)

R. Golbedaghi

2014-01-01

Full Text Available The complex formation between a newly synthesized tripodal ligand and the cation Cu2+ in water and surfactant media was studied spectrophotometrically using rank annihilation factor analysis (RAFA. According to molar ratio data the stoichiometry of complexation between the ligand and the cation Cu2+ was 1:1. Formation constant of this complex was derived using RAFA on spectrophotometric data. The performance of the method has been evaluated by using synthetic data. Also concentration and spectral profiles of ligand and complex can be obtained by using the stability constant and appropriate equations. The effect of surfactants such as sodium dodecyl sulfate (SDS, cetyltrimethylammonium bromide (CTAB and Triton X-100 on complex formation constant of Cu2+ with the ligand was investigated.

The biosynthesis and processing of high molecular weight precursors of soybean glycinin subunits.

Science.gov (United States)

Barton, K A; Thompson, J F; Madison, J T; Rosenthal, R; Jarvis, N P; Beachy, R N

1982-06-10

The predominant storage protein of soybean seed, glycinin, is composed of two heterogeneous classes of related subunits, the acidics (Mr approximately 38,000) and the basics (Mr approximately 22,000). Immunoreaction of polypeptides translated in vitro from isolated seed mRNA using antibodies prepared against either purified acidic or basic subunit groups precipitated precursor polypeptides of Mr = 60,000 to Mr = 63,000. High pressure liquid chromatography fingerprinting of trypsin-generated fragments from in vitro synthesized precursors showed fragments specific to both acidic and basic subunits. No mature acidic or basic subunits were detected in vitro translation reactions by either immunoprecipitation or high pressure liquid chromatography fingerprinting. Pulse-labeling of cotyledons growing in culture with [3H]glycine showed rapid accumulation of label in glycinin precursors of Mr = 59,000 to Mr = 62,000. Although in vivo synthesized precursors had slightly greater electrophoretic mobility than in vitro synthesized precursors, little label initially appeared in mature glycinin subunits. After several hours of continued cotyledon growth in absence of label, precursors were processed and label accumulated in both acidic and basic subunit groups. Recombinant plasmids were prepared by reverse transcription of soybean seed mRNA, and clones which encode glycinin precursors were identified by heteroduplex-hybridization of translatable messages. Northern blot analysis of seed mRNA shows the mRNA-encoding glycinin precursors to migrate at Mr = 0.71 X 10(6) on agarose gels, corresponding to approximately 2050 nucleotides. This is sufficiently large to encode a polypeptide consisting of both a glycinin acidic and basic subunit.

Possible origin of Saturn's newly discovered outer ring

International Nuclear Information System (INIS)

Moehlmann, D.

1986-01-01

Within a planetogonic model the self-gravitationally caused formation of pre-planetary and pre-satellite rings from an earlier thin disk is reported. The theoretically derived orbital radii of these rings are compared with the orbital levels in the planetary system and the satellite systems of Jupiter, Saturn and Uranus. From this comparison it is concluded that at the radial position of Saturn's newly discovered outer ring an early pre-satellite ring of more or less evolved satellites could have existed. These satellites should have been disturbed in their evolution by the gravitation of the neighbouring massive satellite Titan. The comparison also may indicate similarities between the asteroidal belt and the newly discovered outer ring of Saturn

Oral Cancer Knowledge Assessment: Newly Graduated versus Senior Dental Clinicians

Science.gov (United States)

Salgado de Souza, Ricardo; Gallego Arias Pecorari, Vanessa; Lauria Dib, Luciano

2018-01-01

The present study assessed the level of dentists' knowledge regarding oral cancer in the city of São Paulo, Brazil. A questionnaire was used to compare the level of knowledge among newly graduated and senior clinicians. A total of 20,154 e-mails were correctly delivered to the dentists registered in the database of the Regional Dentistry Council of São Paulo, and 477 (2.36%) responses were received. This sample consisted of 84 newly graduated clinicians and 105 senior clinicians. For the statistical analysis, the chi-square test and the logistic regression analysis were performed with α = 0.05, and the results were described herein. According to their knowledge level, the results were statistically different between the groups, since 19% of the newly graduated clinicians were evaluated with knowledge grade A (excellent) in comparison to 6.7% of the senior clinicians. In spite of the results indicated that newly graduated clinicians' knowledge regarding oral cancer was 2.1 times higher, 34.5% of the professionals in this group had regular or poor knowledge on the subject, and several questions relating to clinical characteristics and risk factors indicated that there still exist some knowledge gaps, demonstrating that there is a need for further studies and information activities addressing oral cancer. PMID:29666649

Appearance of newly formed mRNA and rRNA as ribonucleoprotein-particles in the cytoplasmic subribosomal fraction of pea embryos

International Nuclear Information System (INIS)

Takahashi, Noribumi; Takaiwa, Fumio; Fukuei, Keisuke; Sakamaki, Tadashi; Tanifuji, Shigeyuki

1977-01-01

Incorporation studies with 3 H-uridine or 3 H-adenosine showed that germinating pea embryos synthesize all types of poly A(+) RNA, rRNA and 4-5S RNA at the early stage of germination. After the pulse labeling for 30 min, only heterodisperse RNA and 4-5S RNA appeared in the cytoplasm as labeled RNA species. At this time the radioactivity was associated with cytoplasmic structures heavier than 80S and RNP particles of 68-70S, 52-55S, 36-38S and 20-22S which are presumed to be free mRNP particles in plants. When the pulse-labeled embryos were incubated for a further 60 min in an isotope-free medium, the labeled 17S and 25S rRNA emerged in the cytoplasm, together with labeled heterodisperse and 4-5S RNAs. More radioactivity accumulated in the regions of the polysome, 62-65S and 38-42S particles. The results of analysis of RNAs extracted from the whole cytoplasm, polysome or subribosomal fractions indicated that small subunits of newly formed ribosomes appear more rapidly in the cytoplasm than new large subunits, which accumulate for a while as free particles in the cytoplasm than are incorporated into polysomes. The actinomycin treatment which caused preferential inhibition of rRNA synthesis reduced the accumulation of free, newly formed ribosome subunits and partially permitted detection of the presumed mRNP particles in the subribosomal region even after the chase treatment. (auth.)

Operational Design that Synthesizes Art and Science

Science.gov (United States)

2011-05-04

FINAL 3. DATES COVERED (From - To) Feb - May 2011 4. TITLE AND SUBTITLE OPERATIONAL DESIGN THAT SYNTHESIZES ART AND SCIENCE 5a...TITLE AND SUBTITLE Operational Design That Synthesizes Art And Science 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR...proponents of EBO view warfare as only a science and not a combination of art and science . 9 Another main point of contention centered on the term

Career Motivation in Newly Licensed Registered Nurses: What Makes Them Remain

Science.gov (United States)

Banks, Zarata Mann; Bailey, Jessica H.

2010-01-01

Despite vast research on newly licensed registered nurses (RNs), we don't know why some newly licensed registered nurses remain in their current jobs and others leave the nursing profession early in their career. Job satisfaction, the most significant factor emerging from the literature, plays a significant role in nurses' decisions to remain in…

Fully automated parallel oligonucleotide synthesizer

Czech Academy of Sciences Publication Activity Database

Lebl, M.; Burger, Ch.; Ellman, B.; Heiner, D.; Ibrahim, G.; Jones, A.; Nibbe, M.; Thompson, J.; Mudra, Petr; Pokorný, Vít; Poncar, Pavel; Ženíšek, Karel

2001-01-01

Roč. 66, č. 8 (2001), s. 1299-1314 ISSN 0010-0765 Institutional research plan: CEZ:AV0Z4055905 Keywords : automated oligonucleotide synthesizer Subject RIV: CC - Organic Chemistry Impact factor: 0.778, year: 2001

Meeting and activating the newly unemployed

DEFF Research Database (Denmark)

Rotger, Gabriel Pons

-demanding activity. As intensive activation is usually accompanied by intensive search monitoring, it is important to disentangling the contribution of the costly activation programs from that of caseworker meetings. Using Danish data for the period 2010-13, the paper shows that requiring newly unemployed intensive...... activation, contrary to job search meetings, reduces employment and increases sickness benefit claims....

Design of a Software for Calculating Isoelectric Point of a Polypeptide According to Their Net Charge Using the Graphical Programming Language LabVIEW

Science.gov (United States)

Tovar, Glomen

2018-01-01

A software to calculate the net charge and to predict the isoelectric point (pI) of a polypeptide is developed in this work using the graphical programming language LabVIEW. Through this instrument the net charges of the ionizable residues of the chains of the proteins are calculated at different pH values, tabulated, pI is predicted and an Excel…

Single nucleotide polymorphisms in the 5'-flanking region of the ...

African Journals Online (AJOL)

Prolactin (PRL), a polypeptide hormone synthesized and secreted by the animal's anterior pituitary gland, plays an important role in the regulation of mammalian lactation and avian reproduction. Considering the significant association between single nucleotide polymorphisms (SNPs) in the 5'-flanking region of PRL and ...

Widely tunable THz synthesizer

Science.gov (United States)

Hindle, F.; Mouret, G.; Eliet, S.; Guinet, M.; Cuisset, A.; Bocquet, R.; Yasui, T.; Rovera, D.

2011-09-01

The generation of cw-THz radiation by photomixing is particularly suited to the high resolution spectroscopy of gases; nevertheless, until recently, it has suffered from a lack of frequency metrology. Frequency combs are a powerful tool that can transfer microwave frequency standards to optical frequencies and a single comb has permitted accurate (10-8) THz frequency synthesis with a limited tuning range. A THz synthesizer composed of three extended cavity laser diodes phase locked to a frequency comb has been constructed and its utility for high resolution gas phase spectroscopy demonstrated. The third laser diode allows a larger tuning range of up to 300 MHz to be achieved without the need for large frequency excursions, while the frequency comb provides a versatile link to be established from any traceable microwave frequency standard. The use of a single frequency comb as a reference for all of the cw-lasers eliminates the dependency of synthesized frequency on the carrier envelope offset frequency. This greatly simplifies the frequency comb stabilization requirements and leads to a reduced instrument complexity.

Anticancer Activity of Cobra Venom Polypeptide, Cytotoxin-II, against Human Breast Adenocarcinoma Cell Line (MCF-7) via the Induction of Apoptosis

OpenAIRE

Ebrahim, Karim; Shirazi, Farshad H.; Vatanpour, Hosein; zare, Abas; Kobarfard, Farzad; Rabiei, Hadi

2014-01-01

Purpose Breast cancer is a significant health problem worldwide, accounting for a quarter of all cancer diagnoses in women. Current strategies for breast cancer treatment are not fully effective, and there is substantial interest in the identification of novel anticancer agents especially from natural products including toxins. Cytotoxins are polypeptides found in the venom of cobras and have various physiological effects. In the present study, the anticancer potential of cytotoxin-II against...

Competence of newly qualified registered nurses from a nursing college

Directory of Open Access Journals (Sweden)

BG Morolong

2005-09-01

Full Text Available The South African education and training system, through its policy of outcomesbased education and training, has made competency a national priority. In compliance to this national requirement of producing competent learners, the South African Nursing Council ( 1999 B require that the beginner professional nurse practitioners and midwives have the necessary knowledge, skills, attitudes and values which will enable them to render efficient professional service. The health care system also demands competent nurse practitioners to ensure quality in health care. In the light of competency being a national priority and a statutory demand, the research question that emerges is, how competent are the newly qualified registered nurses from a specific nursing college in clinical nursing education? A quantitative, non-experimental contextual design was used to evaluate the competence of newly qualified registered nurses from a specific nursing college. The study was conducted in two phases. The first phase dealt with the development of an instrument together with its manual through the conceptualisation process. The second phase focused on the evaluation of the competency of newly qualified nurses using the instrument based on the steps of the nursing process. A pilot study was conducted to test the feasibility of the items of the instrument. During the evaluation phase, a sample of twenty-six newly qualified nurses was selected by simple random sampling from a target population of thirty-six newly qualified registered nurses. However, six participants withdrew from the study. Data was collected in two general hospitals where the newly qualified registered nurses were working. Observation and questioning were used as data collection techniques in accordance with the developed instrument. Measures were taken to ensure internal validity and reliability of the results. To protect the rights of the participants, the researcher adhered to DENOSA’S (1998

l-Cystine-Crosslinked Polypeptide Nanogel as a Reduction-Responsive Excipient for Prostate Cancer Chemotherapy

Directory of Open Access Journals (Sweden)

Liang He

2016-01-01

Full Text Available Smart polymer nanogel-assisted drug delivery systems have attracted more and more attention in cancer chemotherapy because of their well-defined morphologies and pleiotropic functions in recent years. In this work, an l-cystine-crosslinked reduction-responsive polypeptide nanogel of methoxy poly(ethylene glycol-poly(l-phenylalanine-co-l-cystine (mPEG-P(LP-co-LC was employed as a smart excipient for RM-1 prostate cancer (PCa chemotherapy. Doxorubicin (DOX, as a regular chemotherapy drug, was embedded in the nanogel. The loading nanogel marked as NG/DOX was shown to exhibit glutathione (GSH-induced swelling and GSH-accelerated DOX release. Subsequently, NG/DOX showed efficient cellular uptake and proliferation inhibition. Furthermore, NG/DOX presented enhanced antitumor efficacy and security in an RM-1 PCa-grafted mouse model in vivo, indicating its great potential for clinical treatment.

Islet amyloid polypeptide and high hydrostatic pressure: towards an understanding of the fibrillization process

Science.gov (United States)

Lopes, D. H. J.; Smirnovas, V.; Winter, R.

2008-07-01

Type II Diabetes Mellitus is a disease which is characterized by peripheral insulin resistance coupled with a progressive loss of insulin secretion that is associated with a decrease in pancreatic islet β-cell mass and the deposition of amyloid in the extracellular matrix of β-cells, which lead to islet cell death. The principal component of the islet amyloid is a pancreatic hormone called islet amyloid polypeptide (IAPP). High-pressure coupled with FT-IR, CD, ThT fluorescence spectroscopic and AFM studies were carried out to reveal information on the aggregation pathway as well as the aggregate structure of IAPP. Our data indicate that IAPP pre-formed fibrils exhibit a strong polymorphism with heterogeneous structures very sensitive to high hydrostatic pressure, indicating a high percentage of ionic and hydrophobic interactions being responsible for the stability the IAPP fibrils.

Distribution and protective function of pituitary adenylate cyclase-activating polypeptide (PACAP in the retina

Directory of Open Access Journals (Sweden)

Tomoya eNakamachi

2012-11-01

Full Text Available Pituitary adenylate cyclase-activating polypeptide (PACAP, which is found in 27- or 38-amino acid forms, belongs to the VIP/glucagon/secretin family. PACAP and its three receptor subtypes are expressed in neural tissues, with PACAP known to exert a protective effect against several types of neural damage. The retina is considered to be part of the central nervous system, and retinopathy is a common cause of profound and intractable loss of vision. This review will examine the expression and morphological distribution of PACAP and its receptors in the retina, and will summarize the current state of knowledge regarding the protective effect of PACAP against different kinds of retinal damage, such as that identified in association with diabetes, ultraviolet light, hypoxia, optic nerve transection, and toxins. This article will also address PACAP-mediated protective pathways involving retinal glial cells.

Convergent synthesis of proteins by kinetically controlled ligation

Science.gov (United States)

Kent, Stephen; Pentelute, Brad; Bang, Duhee; Johnson, Erik; Durek, Thomas

2010-03-09

The present invention concerns methods and compositions for synthesizing a polypeptide using kinetically controlled reactions involving fragments of the polypeptide for a fully convergent process. In more specific embodiments, a ligation involves reacting a first peptide having a protected cysteyl group at its N-terminal and a phenylthioester at its C-terminal with a second peptide having a cysteine residue at its N-termini and a thioester at its C-termini to form a ligation product. Subsequent reactions may involve deprotecting the cysteyl group of the resulting ligation product and/or converting the thioester into a thiophenylester.

Clinical heterogeneity in newly diagnosed Parkinson's disease

NARCIS (Netherlands)

Post, Bart; Speelman, Johannes D.; de Haan, Rob J.

2008-01-01

OBJECTIVE: To determine clinical heterogeneity in newly diagnosed Parkinson's disease using cluster analysis and to describe the subgroups in terms of impairment, disability, perceived quality of life, and use of dopaminergic therapy. METHODS: We conducted a k-means cluster analysis in a prospective

A frequency tracking synthesizer for beam diagnostic systems

International Nuclear Information System (INIS)

Peterson, D.; Marriner, J.

1991-01-01

In low and medium energy synchrotrons the beam revolution frequency changes by a large factor during the acceleration process. High production rates require that these machines cycle rapidly. In attempting to diagnose instabilities which develop during the acceleration process it is useful to be able to select some frequency segment between revolution harmonics for viewing. Most types of test equipment operating in the frequency domain, such as spectrum analyzers and network analyzers, are not suited to making direct measurements on such rapidly sweeping signals. Ideally, one would want to set the frequency frame of reference to the spot in the accelerating revolution harmonic domain where the measurements are to be made. A scheme using a direct digital synthesizer (DDS) was developed to provide this moving reference frame. This paper describes a synthesizer scheme combining digital and analog synthesizer techniques to allow tracking of signals during acceleration. Virtually any ratio of synthesizer to beam revolution frequency may be generated by this scheme. Details of hardware and measurement results are presented

Pancreatic polypeptide: Identification of target tissues and investigation of possible physiologic significance

International Nuclear Information System (INIS)

Shetzline, M.A.

1988-01-01

Pancreatic Polypeptide (PP) is a 36 amino acid peptide with hormonal properties but whose physiologic function remains unknown. In order to determine the function of this peptide we investigated potential target tissues using an in vivo radioreceptor assay. In vitro high concentrations of unlabeled hormone competitively inhibit low concentrations of labeled hormone from binding to receptors. Our in vivo studies indicate that, in the presence of concentrated unlabeled peptide, labeled PP distributes between the plasma and interstitial fluid. When saline rather than excess unlabeled PP is injected, the labeled peptide appears to distribute in a volume exceeding the combined plasma and interstitial fluid volume of tissue. The distribution volume which exceeds the anatomic extracellular volume and which is not present with excess unlabeled peptide, is the receptor compartment. With this assay we demonstrated in the rat specific and displaceable PP binding to the ductus choledochus, duodenum, ileum, and adrenal gland. In vitro rat adrenal cell membranes showed specific I-125 labeled PP binding. Specific binding also occurred in bovine cortical and medullary membranes

[Principles of nutrition in patients with newly appointed stoma].

Science.gov (United States)

Pachocka, Lucyna Małgorzata; Urbanik, Anna

2016-01-01

The treatment of intestinal stoma is often a difficult experience for patients and results in numerous problems in the physical, psychological and social aspects. Therefore, post-operative care of the patient with the newly appointed stoma should be taken by therapeutic team consisting of doctors, nurses, physiotherapists, dieticians, psychologists and social workers. Appropriate nutritional education of patients aims to improve their quality of life and to prevent from unpleasant ailments formed after the operation. The specific type of stoma may decide about certain dietary recommendations. The presented work provides a practical dietary recommendations for patients with newly appointed stoma.

Design of monodisperse and well-defined polypeptide-based polyvalent inhibitors of anthrax toxin.

Science.gov (United States)

Patke, Sanket; Boggara, Mohan; Maheshwari, Ronak; Srivastava, Sunit K; Arha, Manish; Douaisi, Marc; Martin, Jacob T; Harvey, Ian B; Brier, Matthew; Rosen, Tania; Mogridge, Jeremy; Kane, Ravi S

2014-07-28

The design of polyvalent molecules, presenting multiple copies of a specific ligand, represents a promising strategy to inhibit pathogens and toxins. The ability to control independently the valency and the spacing between ligands would be valuable for elucidating structure-activity relationships and for designing potent polyvalent molecules. To that end, we designed monodisperse polypeptide-based polyvalent inhibitors of anthrax toxin in which multiple copies of an inhibitory toxin-binding peptide were separated by flexible peptide linkers. By tuning the valency and linker length, we designed polyvalent inhibitors that were over four orders of magnitude more potent than the corresponding monovalent ligands. This strategy for the rational design of monodisperse polyvalent molecules may not only be broadly applicable for the inhibition of toxins and pathogens, but also for controlling the nanoscale organization of cellular receptors to regulate signaling and the fate of stem cells. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A paclitaxel-loaded recombinant polypeptide nanoparticle outperforms Abraxane in multiple murine cancer models

Science.gov (United States)

Bhattacharyya, Jayanta; Bellucci, Joseph J.; Weitzhandler, Isaac; McDaniel, Jonathan R.; Spasojevic, Ivan; Li, Xinghai; Lin, Chao-Chieh; Chi, Jen-Tsan Ashley; Chilkoti, Ashutosh

2015-08-01

Packaging clinically relevant hydrophobic drugs into a self-assembled nanoparticle can improve their aqueous solubility, plasma half-life, tumour-specific uptake and therapeutic potential. To this end, here we conjugated paclitaxel (PTX) to recombinant chimeric polypeptides (CPs) that spontaneously self-assemble into ~60 nm near-monodisperse nanoparticles that increased the systemic exposure of PTX by sevenfold compared with free drug and twofold compared with the Food and Drug Administration-approved taxane nanoformulation (Abraxane). The tumour uptake of the CP-PTX nanoparticle was fivefold greater than free drug and twofold greater than Abraxane. In a murine cancer model of human triple-negative breast cancer and prostate cancer, CP-PTX induced near-complete tumour regression after a single dose in both tumour models, whereas at the same dose, no mice treated with Abraxane survived for >80 days (breast) and 60 days (prostate), respectively. These results show that a molecularly engineered nanoparticle with precisely engineered design features outperforms Abraxane, the current gold standard for PTX delivery.

Dock 'n roll: folding of a silk-inspired polypeptide into an amyloid-like beta solenoid.

Science.gov (United States)

Zhao, Binwu; Cohen Stuart, Martien A; Hall, Carol K

2016-04-20

Polypeptides containing the motif ((GA)mGX)n occur in silk and have a strong tendency to self-assemble. For example, polypeptides containing (GAGAGAGX)n, where X = G or H have been observed to form filaments; similar sequences but with X = Q have been used in the design of coat proteins (capsids) for artificial viruses. The structure of the (GAGAGAGX)m filaments has been proposed to be a stack of peptides in a β roll structure with the hydrophobic side chains pointing outwards (hydrophobic shell). Another possible configuration, a β roll or β solenoid structure which has its hydrophobic side chains buried inside (hydrophobic core) was, however, overlooked. We perform ground state analysis as well as atomic-level molecular dynamics simulations, both on single molecules and on two-molecule stacks of the silk-inspired sequence (GAGAGAGQ)10, to decide whether the hydrophobic core or the hydrophobic shell configuration is the most stable one. We find that a stack of two hydrophobic core molecules is energetically more favorable than a stack of two hydrophobic shell molecules. A shell molecule initially placed in a perfect β roll structure tends to rotate its strands, breaking in-plane hydrogen bonds and forming out-of-plane hydrogen bonds, while a core molecule stays in the β roll structure. The hydrophobic shell structure has type II' β turns whereas the core configuration has type II β turns; only the latter secondary structure agrees well with solid-state NMR experiments on a similar sequence (GA)15. We also observe that the core stack has a higher number of intra-molecular hydrogen bonds and a higher number of hydrogen bonds between stack and water than the shell stack. Hence, we conclude that the hydrophobic core configuration is the most likely structure. In the stacked state, each peptide has more intra-molecular hydrogen bonds than a single folded molecule, which suggests that stacking provides the extra stability needed for molecules to reach the folded

Two Newly Discovered Plants in Taiwan

OpenAIRE

Tian-Chuan Hsu; Jia-Jung Lin; Shih-Wen Chung

2009-01-01

Two herbs are newly discovered in Taiwan. Limnophila fragrans (G. Forst.) Seem. (Scrophulariaceae), native in SE Asia, is recognized from southern lowlands. Anagallis minima (L.) E. H. L. Krause (Primulaceae), native in N America and Europe, was found from northern mountainous region at low altitudes. In this study, descriptions, line drawings, color photos and a distribution map of the two species are provided.

Newly-formed emotional memories guide selective attention processes: Evidence from event-related potentials.

Science.gov (United States)

Schupp, Harald T; Kirmse, Ursula; Schmälzle, Ralf; Flaisch, Tobias; Renner, Britta

2016-06-20

Emotional cues can guide selective attention processes. However, emotional stimuli can both activate long-term memory representations reflecting general world knowledge and engage newly formed memory representations representing specific knowledge from the immediate past. Here, the self-completion feature of associative memory was utilized to assess the regulation of attention processes by newly-formed emotional memory. First, new memory representations were formed by presenting pictures depicting a person either in an erotic pose or as a portrait. Afterwards, to activate newly-built memory traces, edited pictures were presented showing only the head region of the person. ERP recordings revealed the emotional regulation of attention by newly-formed memories. Specifically, edited pictures from the erotic compared to the portrait category elicited an early posterior negativity and late positive potential, similar to the findings observed for the original pictures. A control condition showed that the effect was dependent on newly-formed memory traces. Given the large number of new memories formed each day, they presumably make an important contribution to the regulation of attention in everyday life.

Newly-formed emotional memories guide selective attention processes: Evidence from event-related potentials

Science.gov (United States)

Schupp, Harald T.; Kirmse, Ursula; Schmälzle, Ralf; Flaisch, Tobias; Renner, Britta

2016-01-01

Emotional cues can guide selective attention processes. However, emotional stimuli can both activate long-term memory representations reflecting general world knowledge and engage newly formed memory representations representing specific knowledge from the immediate past. Here, the self-completion feature of associative memory was utilized to assess the regulation of attention processes by newly-formed emotional memory. First, new memory representations were formed by presenting pictures depicting a person either in an erotic pose or as a portrait. Afterwards, to activate newly-built memory traces, edited pictures were presented showing only the head region of the person. ERP recordings revealed the emotional regulation of attention by newly-formed memories. Specifically, edited pictures from the erotic compared to the portrait category elicited an early posterior negativity and late positive potential, similar to the findings observed for the original pictures. A control condition showed that the effect was dependent on newly-formed memory traces. Given the large number of new memories formed each day, they presumably make an important contribution to the regulation of attention in everyday life. PMID:27321471

Pollen parameters estimates of genetic variability among newly ...

African Journals Online (AJOL)

Pollen parameters estimates of genetic variability among newly selected Nigerian roselle (Hibiscus sabdariffa L.) genotypes. ... Estimates of some pollen parameters where used to assess the genetic diversity among ... HOW TO USE AJOL.

Tricks of the trade: time management tips for newly qualified doctors.

Science.gov (United States)

Offiah, Gozie; Doherty, Eva

2018-03-01

The transition from medical student to doctor is an important milestone. The discovery that their time is no longer their own and that the demands of their job are greater than the time they have available is extremely challenging. At a recent surgical boot camp training programme, 60 first-year surgical trainees who had just completed their internship were invited to reflect on the lessons learnt regarding effective time management and to recommend tips for their newly qualified colleagues. They were asked to identify clinical duties that were considered urgent and important using the time management matrix and the common time traps encountered by newly qualified doctors. The surgical trainees identified several practical tips that ranged from writing a priority list to working on relationships within the team. These tips are generic and so applicable to all newly qualified medial doctors. We hope that awareness of these tips from the outset as against learning them through experience will greatly assist newly qualified doctors. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Chest Radiographic Findings in Newly Diagnosed Pulmonary ...

African Journals Online (AJOL)

Five hundred newly diagnosed cases of Pulmonary Tuberculosis were treated with directly observed short-course treatment and 100 of them had chest radiographic examination done. The various chest radiographic patterns in the 100 subjects were studied and included: Fluffy exudative changes 80(80%), fibrosis 70(70%) ...

Transport stress induces heart damage in newly hatched chicks via blocking the cytoprotective heat shock response and augmenting nitric oxide production.

Science.gov (United States)

Sun, F; Zuo, Y-Z; Ge, J; Xia, J; Li, X-N; Lin, J; Zhang, C; Xu, H-L; Li, J-L

2018-04-20

Transport stress affects the animal's metabolism and psychological state. As a pro-survival pathway, the heat shock response (HSR) protects healthy cells from stressors. However, it is unclear whether the HSR plays a role in transport stress-induced heart damage. To evaluate the effects of transport stress on heart damage and HSR protection, newly hatched chicks were treated with transport stress for 2 h, 4 h and 8 h. Transport stress caused decreases in body weight and increases in serum creatine kinase (CK) activity, nitric oxide (NO) content in heart tissue, cardiac nitric oxide syntheses (NOS) activity and NOS isoforms transcription. The mRNA expression of heat shock factors (HSFs, including HSF1-3) and heat shock proteins (HSPs, including HSP25, HSP40, HSP47, HSP60, HSP70, HSP90 and HSP110) in the heart of 2 h transport-treated chicks was upregulated. After 8 h of transport stress in chicks, the transcription levels of the same HSPs and HSF2 were reduced in the heart. It was also found that the changes in the HSP60, HSP70 and HSP90 protein levels had similar tendencies. These results suggested that transport stress augmented NO generation through enhancing the activity of NOS and the transcription of NOS isoforms. Therefore, this study provides new evidence that transport stress induces heart damage in the newly hatched chicks by blocking the cytoprotective HSR and augmenting NO production.

Polyglycerol-functionalized nanodiamond as a platform for gene delivery: Derivatization, characterization, and hybridization with DNA

Directory of Open Access Journals (Sweden)

Li Zhao

2014-03-01

Full Text Available A gene vector consisting of nanodiamond, polyglycerol, and basic polypeptide (ND-PG-BPP has been designed, synthesized, and characterized. The ND-PG-BPP was synthesized by PG functionalization of ND through ring-opening polymerization of glycidol on the ND surface, multistep organic transformations (–OH → –OTs (tosylate → –N3 in the PG layer, and click conjugation of the basic polypeptides (Arg8, Lys8 or His8 terminated with propargyl glycine. The ND-PG-BPP exhibited good dispersibility in water (>1.0 mg/mL and positive zeta potential ranging from +14.2 mV to +44.1 mV at neutral pH in Milli-Q water. It was confirmed by gel retardation assay that ND-PG-Arg8 and ND-PG-Lys8 with higher zeta potential hybridized with plasmid DNA (pDNA through electrostatic attraction, making them promising as nonviral vectors for gene delivery.

Polyglycerol-functionalized nanodiamond as a platform for gene delivery: Derivatization, characterization, and hybridization with DNA

Science.gov (United States)

Zhao, Li; Nakae, Yuki; Qin, Hongmei; Ito, Tadamasa; Kimura, Takahide; Kojima, Hideto; Chan, Lawrence

2014-01-01

Summary A gene vector consisting of nanodiamond, polyglycerol, and basic polypeptide (ND-PG-BPP) has been designed, synthesized, and characterized. The ND-PG-BPP was synthesized by PG functionalization of ND through ring-opening polymerization of glycidol on the ND surface, multistep organic transformations (–OH → –OTs (tosylate) → –N3) in the PG layer, and click conjugation of the basic polypeptides (Arg8, Lys8 or His8) terminated with propargyl glycine. The ND-PG-BPP exhibited good dispersibility in water (>1.0 mg/mL) and positive zeta potential ranging from +14.2 mV to +44.1 mV at neutral pH in Milli-Q water. It was confirmed by gel retardation assay that ND-PG-Arg8 and ND-PG-Lys8 with higher zeta potential hybridized with plasmid DNA (pDNA) through electrostatic attraction, making them promising as nonviral vectors for gene delivery. PMID:24778723

Polypeptoids: A perfect match for molecular definition and macromolecular engineering?

KAUST Repository

Luxenhofer, Robert

2013-04-19

Precision synthesis of polymers has been a hot topic in recent years. While this is notoriously difficult to address for polymers with a CC backbone, Merrifield has discovered a way many decades ago for polypeptides. Using a similar approach, N-substituted polypeptides, so-called polypeptoids have been synthesized and studied for about 20 years. In contrast, the living ring-opening polymerization (ROP) of N-substituted N-carboxyanhydrides was among the first living polymerizations to be discovered. More recently, a surge in new synthetic approaches led to the efficient synthesis of cyclic or linear multiblock copolypeptoids. Thus, polypeptoids can be synthesized either by solid phase synthesis to yield complex and exactly defined oligo- and small polymers or by ROP of appropriately N-substituted N-carboxyanhydrides (NNCA) to give linear, cyclic, or star-like polymers. Together with an excellent biocompatibility, this polymer family may have a bright future ahead as biomaterials. © 2013 Wiley Periodicals, Inc.

A plant small polypeptide is a novel component of DNA-binding protein phosphatase 1-mediated resistance to plum pox virus in Arabidopsis.

Science.gov (United States)

Castelló, María José; Carrasco, Jose Luis; Navarrete-Gómez, Marisa; Daniel, Jacques; Granot, David; Vera, Pablo

2011-12-01

DNA-binding protein phosphatases (DBPs) have been identified as a novel class of plant-specific regulatory factors playing a role in plant-virus interactions. NtDBP1 from tobacco (Nicotiana tabacum) was shown to participate in transcriptional regulation of gene expression in response to virus infection in compatible interactions, and AtDBP1, its closest relative in the model plant Arabidopsis (Arabidopsis thaliana), has recently been found to mediate susceptibility to potyvirus, one of the most speciose taxa of plant viruses. Here, we report on the identification of a novel family of highly conserved small polypeptides that interact with DBP1 proteins both in tobacco and Arabidopsis, which we have designated DBP-interacting protein 2 (DIP2). The interaction of AtDIP2 with AtDBP1 was demonstrated in vivo by bimolecular fluorescence complementation, and AtDIP2 was shown to functionally interfere with AtDBP1 in yeast. Furthermore, reducing AtDIP2 gene expression leads to increased susceptibility to the potyvirus Plum pox virus and to a lesser extent also to Turnip mosaic virus, whereas overexpression results in enhanced resistance. Therefore, we describe a novel family of conserved small polypeptides in plants and identify AtDIP2 as a novel host factor contributing to resistance to potyvirus in Arabidopsis.

Newly graduated nurses' empowerment regarding professional competence and other work-related factors.

Science.gov (United States)

Kuokkanen, Liisa; Leino-Kilpi, Helena; Numminen, Olivia; Isoaho, Hannu; Flinkman, Mervi; Meretoja, Riitta

2016-01-01

Although both nurse empowerment and competence are fundamental concepts of describing newly graduated nurses' professional development and job satisfaction, only few studies exist on the relationship between these concepts. Therefore, the purpose of this study was to determine how newly graduated nurses assess their empowerment and to clarify professional competence compared to other work-related factors. A descriptive, cross-sectional and correlational design was applied. The sample comprised newly graduated nurses (n = 318) in Finland. Empowerment was measured using the 19-item Qualities of an Empowered Nurse scale and the Nurse Competence Scale measured nurses' self-assessed generic competence. In addition to demographic data, the background data included employment sector (public/private), job satisfaction, intent to change/leave job, work schedule (shifts/business hours) and assessments of the quality of care in the workplace. The data were analysed statistically by using Spearman's correlation coefficient as well as the One-Way and Multivariate Analysis of Variance. Cronbach's alpha coefficient was used to estimate the internal consistency. Newly graduated nurses perceived their level of empowerment and competence fairly high. The association between nurse empowerment and professional competence was statistically significant. Other variables correlating positively to empowerment included employment sector, age, job satisfaction, intent to change job, work schedule, and satisfaction with the quality of care in the work unit. The study indicates competence had the strongest effect on newly graduated nurses' empowerment. New graduates need support and career opportunities. In the future, nurses' further education and nurse managers' resources for supporting and empowering nurses should respond to the newly graduated nurses' requisites for attractive and meaningful work.

Method of synthesizing pyrite nanocrystals

Science.gov (United States)

Wadia, Cyrus; Wu, Yue

2013-04-23

A method of synthesizing pyrite nanocrystals is disclosed which in one embodiment includes forming a solution of iron (III) diethyl dithiophosphate and tetra-alkyl-ammonium halide in water. The solution is heated under pressure. Pyrite nanocrystal particles are then recovered from the solution.

Two Newly Discovered Plants in Taiwan

Directory of Open Access Journals (Sweden)

Tian-Chuan Hsu

2009-11-01

Full Text Available Two herbs are newly discovered in Taiwan. Limnophila fragrans (G. Forst. Seem. (Scrophulariaceae, native in SE Asia, is recognized from southern lowlands. Anagallis minima (L. E. H. L. Krause (Primulaceae, native in N America and Europe, was found from northern mountainous region at low altitudes. In this study, descriptions, line drawings, color photos and a distribution map of the two species are provided.

Diabetes education and self-management for ongoing and newly diagnosed (DESMOND)

DEFF Research Database (Denmark)

Skinner, T. Chas; Carey, Marian E.; Cradock, Sue

2006-01-01

diagnosed with Type 2 diabetes changes key illness beliefs and that these changes predict quality of life and metabolic control at 3-month follow-up. Practice implications: Newly diagnosed individuals are open to attending self-management programs and, if the program is theoretically driven, can......Objective: To determine the effects of a structured education program on illness beliefs, quality of life and physical activity in people newly diagnosed with Type 2 diabetes. Methods: Individuals attending a diabetes education and self-management for ongoing and newly diagnosed (DESMOND) program...... in 12 Primary Care Trusts completed questionnaire booklets assessing illness beliefs and quality of life at baseline and 3-month follow-up, metabolic control being assessed through assay of HbA1c. Results: Two hundred and thirty-six individuals attended the structured self-management education sessions...

Bio-inspired synthesis of hybrid silica nanoparticles templated from elastin-like polypeptide micelles

Science.gov (United States)

Han, Wei; MacEwan, Sarah R.; Chilkoti, Ashutosh; López, Gabriel P.

2015-07-01

The programmed self-assembly of block copolymers into higher order nanoscale structures offers many attractive attributes for the development of new nanomaterials for numerous applications including drug delivery and biosensing. The incorporation of biomimetic silaffin peptides in these block copolymers enables the formation of hybrid organic-inorganic materials, which can potentially enhance the utility and stability of self-assembled nanostructures. We demonstrate the design, synthesis and characterization of amphiphilic elastin-like polypeptide (ELP) diblock copolymers that undergo temperature-triggered self-assembly into well-defined spherical micelles. Genetically encoded incorporation of the silaffin R5 peptide at the hydrophilic terminus of the diblock ELP leads to presentation of the silaffin R5 peptide on the coronae of the micelles, which results in localized condensation of silica and the formation of near-monodisperse, discrete, sub-100 nm diameter hybrid ELP-silica particles. This synthesis method, can be carried out under mild reaction conditions suitable for bioactive materials, and will serve as the basis for the development and application of functional nanomaterials. Beyond silicification, the general strategies described herein may also be adapted for the synthesis of other biohybrid nanomaterials as well.The programmed self-assembly of block copolymers into higher order nanoscale structures offers many attractive attributes for the development of new nanomaterials for numerous applications including drug delivery and biosensing. The incorporation of biomimetic silaffin peptides in these block copolymers enables the formation of hybrid organic-inorganic materials, which can potentially enhance the utility and stability of self-assembled nanostructures. We demonstrate the design, synthesis and characterization of amphiphilic elastin-like polypeptide (ELP) diblock copolymers that undergo temperature-triggered self-assembly into well

An Investigation of the Polypeptide, Poly - L - Glutamic Acid, Using Neutron Inelastic Scattering

International Nuclear Information System (INIS)

Whittemore, W.L.

1968-01-01

The polypeptides are synthetic polymers of amino acids with many similarities to natural proteins. In a large number of cases, one of the conformations for both the synthetic and natural proteins is the α - helix. The simplest of the synthetic polymers with no side chains is polyglycine and the simplest of the synthetic polymers with a small side chain (methyl group) is polyalanine. Dispersion curves have been computed by Gupta for both of these polymers. Polyglutamic acid is similar to polyalanine in that the composition of the basic residue and radius of helix is the same. Polyglutamic acid has a more complicated side chain which will contribute a number of additional natural frequencies that are expected to be essentially independent of conformation. On the other hand, the dispersion curves already derived for polyalanine in the α -helix form should be correct in many specific details for polyglutamic acid. An experimental study has been undertaken for polyglutamic acid at room temperature using the techniques of inelastic neutron scattering. In the first measurements, 'cold' neutrons from a reactor were used to investigate the energy level structure up to ≃ 3 kT for both conformations of the polymer. In addition, the scattering of monoenergetic high-energy neutrons ( > 0.15 eV) provided- by an electron Linac was used to study energy levels above 3 kT. These latter measurements permit comparisons to be made between the calculated and measured results for a much larger range of frequencies (and hence permit a check for a larger number of dispersion curves). This extension of the experimental results to higher frequencies has made it possible to check on the earlier assumption that only the lower frequencies are altered when the conformation is changed. This assumption underlies the evaluation of changes in internal energy with conformation from only the 'cold' neutron data, as is done with the present data. An experiment was performed to evaluate the

An Investigation of the Polypeptide, Poly - L - Glutamic Acid, Using Neutron Inelastic Scattering

Energy Technology Data Exchange (ETDEWEB)

Whittemore, W. L. [Gulf General Atomic Incorporated, San Diego, CA (United States)

1968-09-15

The polypeptides are synthetic polymers of amino acids with many similarities to natural proteins. In a large number of cases, one of the conformations for both the synthetic and natural proteins is the {alpha} - helix. The simplest of the synthetic polymers with no side chains is polyglycine and the simplest of the synthetic polymers with a small side chain (methyl group) is polyalanine. Dispersion curves have been computed by Gupta for both of these polymers. Polyglutamic acid is similar to polyalanine in that the composition of the basic residue and radius of helix is the same. Polyglutamic acid has a more complicated side chain which will contribute a number of additional natural frequencies that are expected to be essentially independent of conformation. On the other hand, the dispersion curves already derived for polyalanine in the {alpha} -helix form should be correct in many specific details for polyglutamic acid. An experimental study has been undertaken for polyglutamic acid at room temperature using the techniques of inelastic neutron scattering. In the first measurements, 'cold' neutrons from a reactor were used to investigate the energy level structure up to Asymptotically-Equal-To 3 kT for both conformations of the polymer. In addition, the scattering of monoenergetic high-energy neutrons ( > 0.15 eV) provided- by an electron Linac was used to study energy levels above 3 kT. These latter measurements permit comparisons to be made between the calculated and measured results for a much larger range of frequencies (and hence permit a check for a larger number of dispersion curves). This extension of the experimental results to higher frequencies has made it possible to check on the earlier assumption that only the lower frequencies are altered when the conformation is changed. This assumption underlies the evaluation of changes in internal energy with conformation from only the 'cold' neutron data, as is done with the present data. An experiment was

Flagellation of Pseudomonas aeruginosa in newly divided cells

Science.gov (United States)

Zhao, Kun; Lee, Calvin; Anda, Jaime; Wong, Gerard

2015-03-01

For monotrichous bacteria, Pseudomonas aeruginosa, after cell division, one daughter cell inherits the old flagellum from its mother cell, and the other grows a new flagellum during or after cell division. It had been shown that the new flagellum grows at the distal pole of the dividing cell when the two daughter cells haven't completely separated. However, for those daughter cells who grow new flagella after division, it still remains unknown at which pole the new flagellum will grow. Here, by combining our newly developed bacteria family tree tracking techniques with genetic manipulation method, we showed that for the daughter cell who did not inherit the old flagellum, a new flagellum has about 90% chances to grow at the newly formed pole. We proposed a model for flagellation of P. aeruginosa.

An engineered polypeptide around nano-sized manganese-calcium oxide: copying plants for water oxidation.

Science.gov (United States)

Najafpour, Mohammad Mahdi; Ghobadi, Mohadeseh Zarei; Sarvi, Bahram; Haghighi, Behzad

2015-09-14

Synthesis of new efficient catalysts inspired by Nature is a key goal in the production of clean fuel. Different compounds based on manganese oxide have been investigated in order to find their water-oxidation activity. Herein, we introduce a novel engineered polypeptide containing tyrosine around nano-sized manganese-calcium oxide, which was shown to be a highly active catalyst toward water oxidation at low overpotential (240 mV), with high turnover frequency of 1.5 × 10(-2) s(-1) at pH = 6.3 in the Mn(III)/Mn(IV) oxidation range. The compound is a novel structural and efficient functional model for the water-oxidizing complex in Photosystem II. A new proposed clever strategy used by Nature in water oxidation is also discussed. The new model of the water-oxidizing complex opens a new perspective for synthesis of efficient water-oxidation catalysts.

MoS{sub 2}–GO nanocomposites synthesized via a hydrothermal hydrogel method for solar light photocatalytic degradation of methylene blue

Energy Technology Data Exchange (ETDEWEB)

Ding, Yong; Zhou, Yifeng, E-mail: yifengzhou@126.com; Nie, Wangyan; Chen, Pengpeng, E-mail: chenpp@ahu.edu.cn

2015-12-01

Graphical abstract: - Highlights: • The molybdenum disulfide–graphene oxide (MoS{sub 2}–GO) nanocomposite was synthesized via a one-step hydrothermal hydrogel method. • MoS{sub 2} and GO were composited fairly well in the obtained nanocomposites. • The electrons–hole pair recombination rate of MoS{sub 2} was greatly reduced via compositing with graphene. • The MoS{sub 2}–GO nanocomposite exhibited excellent photocatalytic performance for the degradation of methylene blue under solar light irradiation. - Abstract: In this work, molybdenum disulfide–graphene oxide (MoS{sub 2}–GO) composite hydrogel was prepared via a one-step hydrothermal method. The morphology and structure of the as-prepared hydrogels with different proportions of MoS{sub 2} and GO were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, electrochemical impedance spectra and UV–vis absorption spectroscopy. The photocatalytic performance of MoS{sub 2}–GO nanocomposites was studied toward the degradation of methylene blue (MB). Results showed that the MoS{sub 2}–GO nanocomposites exhibited improved photocatalytic activities in the degradation of MB with a maximum degradation rate of 99% under solar lights irradiation within 60 min. The synthesized MoS{sub 2}–GO composite hydrogel possesses great potential toward the development of newly synthesizable catalysts in the field of organic degradation in water.

Nano-level monitoring of Yb(III) by fabrication of coated graphite electrode based on newly synthesized hexaaza macrocyclic ligand

International Nuclear Information System (INIS)

Singh, Ashok K.; Singh, Prerna

2009-01-01

The two macrocyclic ligands 2,12-(2-methoxyaniline) 2 -4,14-Me 2 -[20]-1,4,11,14-tetraene-1,5,8,11,15,18-N 6 (L 1 ) and 2,12-(2-methoxyaniline) 2 -4,14-Me 2 -8,18-dimethylacrylate-[20] -1,4,11,14-tetraene-1,5,8,11,15,18-N 6 (L 2 ) have been synthesized and explored as neutral ionophores for preparing poly(vinylchloride) (PVC) based membrane sensors selective to Yb(III) ions. Effects of various plasticizers and anion excluders were studied in detail and improved performance was observed. The best performance was obtained for the membrane sensor having a composition of L 2 :PVC:BA:NaTPB in the ratio of 5: 40: 52: 3 (w/w; mg). The performance of the membrane based on L 2 was compared with polymeric membrane electrode (PME) as well as with coated graphite electrode (CGE). The electrodes exhibit Nernstian slope for Yb 3+ ions with limits of detection of 4.3 x 10 -8 M for PME and 5.8 x 10 -9 M for CGE. The response time for PME and CGE was found to be 10 s and 8 s, respectively. The potentiometric responses are independent of the pH of the test solution in the pH range 3.0-8.0 for PME and 2.5-8.5 for CGE. The CGE has found to work satisfactorily in partially non-aqueous media upto 30% (v/v) content of methanol, ethanol and 20% (v/v) content of acetonitrile and could be used for a period of 5 months. The CGE was used as indicator electrode in the potentiometric titration of Yb 3+ ions with EDTA and in determination of fluoride ions in mouthwash samples. It can be used for determination of sulfite in red and white wine samples and also in determination of Yb 3+ in various binary mixtures with quantitative results.

Nano-level monitoring of Yb(III) by fabrication of coated graphite electrode based on newly synthesized hexaaza macrocyclic ligand

Energy Technology Data Exchange (ETDEWEB)

Singh, Ashok K., E-mail: akscyfcy@iitr.ernet.in [Department of Chemistry, Indian Institute of Technology-Roorkee, Roorkee 247667 (India); Singh, Prerna [Department of Chemistry, Indian Institute of Technology-Roorkee, Roorkee 247667 (India)

2009-06-08

The two macrocyclic ligands 2,12-(2-methoxyaniline){sub 2}-4,14-Me{sub 2}-[20]-1,4,11,14-tetraene-1,5,8,11,15,18-N{sub 6} (L{sub 1}) and 2,12-(2-methoxyaniline){sub 2}-4,14-Me{sub 2}-8,18-dimethylacrylate-[20] -1,4,11,14-tetraene-1,5,8,11,15,18-N{sub 6} (L{sub 2}) have been synthesized and explored as neutral ionophores for preparing poly(vinylchloride) (PVC) based membrane sensors selective to Yb(III) ions. Effects of various plasticizers and anion excluders were studied in detail and improved performance was observed. The best performance was obtained for the membrane sensor having a composition of L{sub 2}:PVC:BA:NaTPB in the ratio of 5: 40: 52: 3 (w/w; mg). The performance of the membrane based on L{sub 2} was compared with polymeric membrane electrode (PME) as well as with coated graphite electrode (CGE). The electrodes exhibit Nernstian slope for Yb{sup 3+} ions with limits of detection of 4.3 x 10{sup -8} M for PME and 5.8 x 10{sup -9} M for CGE. The response time for PME and CGE was found to be 10 s and 8 s, respectively. The potentiometric responses are independent of the pH of the test solution in the pH range 3.0-8.0 for PME and 2.5-8.5 for CGE. The CGE has found to work satisfactorily in partially non-aqueous media upto 30% (v/v) content of methanol, ethanol and 20% (v/v) content of acetonitrile and could be used for a period of 5 months. The CGE was used as indicator electrode in the potentiometric titration of Yb{sup 3+} ions with EDTA and in determination of fluoride ions in mouthwash samples. It can be used for determination of sulfite in red and white wine samples and also in determination of Yb{sup 3+} in various binary mixtures with quantitative results.

Differential expression of isoproterenol-induced salivary polypeptides in two mouse strains that are congenic for the H-2 histocompatibility gene complex.

Science.gov (United States)

López Solís, Remigio O; Weis, Ulrike Kemmerling; Ceballos, Alicia Ramos; Salas, Gustavo Hoecker

2003-12-01

Two inbred mouse strains, A/Snell and A.Swiss, which were produced as congenic with regard to the H-2 histocompatibility gene complex, are homozygous for two different groups of isoproterenol-induced salivary polypeptides (IISP). These polypeptides, which have been considered as markers of the hypertrophic growth of the parotid acinar cells, are members of the complex family of salivary proline-rich proteins (PRP) on the basis of both their massive accumulation in the parotid acinar cells in response to chronic isoproterenol, secretory character, high solubility in trichloroacetic acid and metachromatic staining by Coomassie blue. IISP expressed in both mouse strains were identified by unidimensional SDS-polyacrylamide electrophoresis and Coomassie blue staining both in parotid gland homogenates and in whole salivas obtained from mice repeatedly stimulated at 24-h intervals with isoproterenol. Parotid glands from 40 mice (20 A/Snell and 20 A.Swiss) and salivas from 270 mice (200 A/Snell and 70 A.Swiss) were analyzed. One of the congenic strains (A/Snell) expressed five IISP (Mr 65, 61, 51.5, 38, and 37 kDa) and the other strain (A.Swiss) expressed six IISP (Mr 59, 57, 54.5, 46, 36, and 34 kDa). No inter-individual intra-strain variations were observed, thus defining strain-associated patterns of IISP (PRP). Copyright 2003 Wiley-Liss, Inc.

Perceptions of the clinical competence of newly registered nurses in the North West province

Directory of Open Access Journals (Sweden)

M.R. Moeti

2004-09-01

Full Text Available The clinical competence of newly registered nurses relating to the care of individual Clients, depends on their ability to correlate theoretical knowledge learned in the classroom with practice and the development of clinical skills. Its foundation lies in the ability to identify and solve problems that emanate from critical thinking, analytical reasoning and reflective practice. It is clear that the quality of clinical exposure plays a leading role in the development of nursing professionals. Nursing skills alone cannot ensure quality care of clients without the application of theory. Facilitation of this theory to practice therefore remains an essential component of nursing education. This study was aimed at identifying areas of incompetence of newly registered nurses (1998- 2001 in the clinical area by determining the newly registered nurses1 and professional nurses1 perceptions of the competence of the newly registered nurses. A quantitative, non-experimental, descriptive survey was used to collect the data regarding the clinical competence of newly registered nurses (1998-2001.

'Practising under your own Pin'- a description of the transition experiences of newly qualified midwives.

Science.gov (United States)

Avis, Mark; Mallik, Maggie; Fraser, Diane M

2013-11-01

Transition experiences of newly qualified midwives were examined in depth during the third phase of a UK evaluation study of midwifery education. The fitness to practise and the retention of newly qualified nursing and midwifery graduates are pressing concerns for health care managers. The advantages of preceptorship are reported in the literature but the content and timing of schemes remain unclear. A semi-structured diary was kept for up to 6 months by 35 newly qualified midwives in 18 work sites covering all countries in the UK. The preceptor and supervisor of midwives for each newly qualified midwife completed short questionnaires about their preceptee's performance, and a further sub-sample of newly qualified midwives and preceptors participated in a semi-structured interview. Data were analysed to elicit aspects of newly qualified midwives transition experiences. Findings confirm that structured preceptorship schemes are not widely available. Newly qualified midwives primarily obtained transition support from members of the midwifery team. Although perceived as competent, there is no demarcation point in becoming confident to practise as a registered practitioner. Implications for managers include the importance of a supportive culture within clinical teams for successful transition and the introduction of structured preceptorship schemes facilitated by appropriate rotation patterns. © 2012 John Wiley & Sons Ltd.

A low-spurious fast-hopping MB-OFDM UWB synthesizer

Energy Technology Data Exchange (ETDEWEB)

Chen Danfeng; Li Wei; Li Ning; Ren Junyan, E-mail: w-li@fudan.edu.c [State Key Laboratory of ASIC and System, Fudan University, Shanghai 201203 (China)

2010-06-15

A frequency synthesizer for the ultra-wide band (UWB) group no. 1 is proposed. The synthesizer uses a phase-locked loop (PLL) and single-sideband (SSB) mixers to generate the three center frequencies of the first band group by mixing 4224 MHz with {+-}264 MHz and 792 MHz, respectively. A novel multi-QSSB mixer is designed to combine the function of frequency selection and frequency conversion for low power and high linearity. The synthesizer is fabricated in Jazz 0.18-{mu}m RF CMOS technology. The measured reference spur is as low as -69 dBc and the maximum spur is the LO leakage of -32 dBc. A low phase noise of -110 dBc/Hz - 1 MHz offset and an integrated phase noise of 1.86{sup 0} are achieved. The hopping time between different bands is less than 1.8 ns. The synthesizer consumes 30 mA from a 1.8 V supply. (semiconductor integrated circuits)

A low-spurious fast-hopping MB-OFDM UWB synthesizer

International Nuclear Information System (INIS)

Chen Danfeng; Li Wei; Li Ning; Ren Junyan

2010-01-01

A frequency synthesizer for the ultra-wide band (UWB) group no. 1 is proposed. The synthesizer uses a phase-locked loop (PLL) and single-sideband (SSB) mixers to generate the three center frequencies of the first band group by mixing 4224 MHz with ±264 MHz and 792 MHz, respectively. A novel multi-QSSB mixer is designed to combine the function of frequency selection and frequency conversion for low power and high linearity. The synthesizer is fabricated in Jazz 0.18-μm RF CMOS technology. The measured reference spur is as low as -69 dBc and the maximum spur is the LO leakage of -32 dBc. A low phase noise of -110 dBc/Hz - 1 MHz offset and an integrated phase noise of 1.86 0 are achieved. The hopping time between different bands is less than 1.8 ns. The synthesizer consumes 30 mA from a 1.8 V supply. (semiconductor integrated circuits)

Synthetic biology projects in vitro.

Science.gov (United States)

Forster, Anthony C; Church, George M

2007-01-01

Advances in the in vitro synthesis and evolution of DNA, RNA, and polypeptides are accelerating the construction of biopolymers, pathways, and organisms with novel functions. Known functions are being integrated and debugged with the aim of synthesizing life-like systems. The goals are knowledge, tools, smart materials, and therapies.

Information Retrieval for Ecological Syntheses

Science.gov (United States)

Bayliss, Helen R.; Beyer, Fiona R.

2015-01-01

Research syntheses are increasingly being conducted within the fields of ecology and environmental management. Information retrieval is crucial in any synthesis in identifying data for inclusion whilst potentially reducing biases in the dataset gathered, yet the nature of ecological information provides several challenges when compared with…

Combustion, performance and emissions characteristics of a newly ...

Indian Academy of Sciences (India)

of a newly developed CRDI single cylinder diesel engine. AVINASH ... In case of unit injector and unit pump systems, fuel injection pressure depends on ... nozzle hole diameters were effective in reducing smoke and PM emissions. However ...

Yield and Adaptability Evaluation of Newly Introduced Tomato ...

African Journals Online (AJOL)

High yield is a major ambition to tomato plant breeders and farmers. The purpose of the ... Tabora Region on the growth and yield of newly introduced tomato varieties. The tested ..... (1985). Evaluation of some American tomatocultivars grown.

Mentorship for newly appointed physicians: a strategy for enhancing patient safety?

Science.gov (United States)

Harrison, Reema; McClean, Serwaa; Lawton, Rebecca; Wright, John; Kay, Clive

2014-09-01

Mentorship is an increasingly popular innovation from business and industry that is being applied in health-care contexts. This paper explores the concept of mentorship for newly appointed physicians in their first substantive senior post, and specifically its utilization to enhance patient safety. Semi-structured face to face and telephone interviews with Medical Directors (n = 5), Deputy Medical Directors (n = 4), and Clinical Directors (n = 6) from 9 acute NHS Trusts in the Yorkshire and Humber region in the north of England. A focused thematic analysis was used. A number of beneficial outcomes were associated with mentorship for newly appointed physicians including greater personal and professional support, organizational commitment, and general well-being. Providing newly appointed senior physicians with support through mentorship was considered to enhance the safety of patient care. Mentorship may prevent or reduce active failures, be used to identify threats in the local working environment, and in the longer term, address latent threats to safety within the organization by encouraging a healthier safety culture. Offering mentorship to all newly appointed physicians in their first substantive post in health care may be a useful strategy to support the development of their clinical, professional, and personal skills in this transitional period that may also enhance the safety of patient care.

Newly elected IAEA Board of Governors

International Nuclear Information System (INIS)

2000-01-01

The document gives information about the election of 11 Member States to the IAEA Board of Governors, the 35-member policy-making body, during the 44th regular session of the IAEA's General Conference (18 - 22 September 2000, Austria Center, Vienna). The newly elected Member States are: Argentina, Egypt, Ghana, Ireland, Libyan Arab Jamahiriya, Mexico, Pakistan, Peru, Switzerland, Thailand, Ukraine. The other 24 Member States of the Board are also given

Transport, Thermal, and Magnetic Properties of YbNi3X9 (X = Al, Ga): A Newly Synthesized Yb-Based Kondo Lattice System

Science.gov (United States)

Yamashita, Tetsuro; Miyazaki, Ryoichi; Aoki, Yuji; Ohara, Shigeo

2012-03-01

We have succeeded in synthesizing a new Yb-based Kondo lattice system, YbNi3X9 (X = Al, Ga). Our study reveals that YbNi3Al9 shows typical features of a heavy-fermion antiferromagnet with a Néel temperature of TN = 3.4 K. All of the properties reflect a competition between the Kondo effect and the crystalline electric field (CEF) effect. The moderate heavy-fermion state leads to an enhanced Sommerfeld coefficient of 100 mJ/(mol\\cdotK2), even if ordered antiferromagnetically. On the other hand, the isostructural gallide YbNi3Ga9 is an intermediate-valence system with a Kondo temperature of TK = 570 K. A large hybridization scale can overcome the CEF splitting energy, and a moderately heavy Fermi-liquid ground state with high local moment degeneracy should form at low temperatures. Note that the quality of single-crystalline YbNi3X9 is extremely high compared with those of other Yb-based Kondo lattice compounds. We conclude that YbNi3X9 is a suitable system for investigating the electronic structure of Yb-based Kondo lattice systems from a heavy-fermion system with an antiferromagnetically ordered ground state to an intermediate-valence system.