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Sample records for asparaginyl endopeptidase legumain

  1. Pig kidney legumain: an asparaginyl endopeptidase with restricted specificity.

    Science.gov (United States)

    Dando, P M; Fortunato, M; Smith, L; Knight, C G; McKendrick, J E; Barrett, A J

    1999-01-01

    Legumain was recently discovered as a lysosomal endopeptidase in mammals [Chen, Dando, Rawlings, Brown, Young, Stevens, Hewitt, Watts and Barrett (1997) J. Biol. Chem. 272, 8090-8098], having been known previously only from plants and invertebrates. It has been shown to play a key role in processing of the C fragment of tetanus toxin for presentation by the MHC class-II system [Manoury, Hewitt, Morrice, Dando, Barrett and Watts (1998) Nature (London) 396, 695-699]. We examine here the specificity of the enzyme from pig kidney by use of protein, oligopeptide and synthetic arylamide substrates, all determinations being made at pH 5.8. In proteins, only about one in ten of the asparaginyl bonds were hydrolysed, and these were mostly predicted to be located at turns on the protein surface. Bonds that were not cleaved in tetanus toxin were cleaved when presented in oligopeptides, sometimes faster than an equivalent oligopeptide based on a bond that was cleaved in the protein. Legumain cleaved the bait region of rat alpha1-macroglobulin and was 'trapped' by the macroglobulin, as most other endopeptidases are, but did not interact with human alpha2-macroglobulin, which contains no asparagine residue in its bait region. Glycosylation of asparagine totally prevented hydrolysis by legumain. Specificity for arylamide substrates was evaluated with reference to benzyloxycarbonyl-Ala-Ala-Asn-aminomethylcoumarin, and the preference for the P3-position amino acid was Ala>Tyr(tertiary butyl)>Val>Pro>Phe=Tyr>Leu=Gly. There was no hydrolysis of substrate analogues containing mono- or di-N-methylasparagines, l-2-amino-3-ureidopropionic acid or citrulline in the P1 position. We conclude that mammalian legumain appears to be totally restricted to the hydrolysis of asparaginyl bonds in substrates of all kinds. There seem to be no strong preferences for particular amino acids in other subsites, and yet there are still unidentified factors that prevent hydrolysis of many asparaginyl bonds

  2. Design of cell-permeable, fluorescent activity-based probes for the lysosomal cysteine protease asparaginyl endopeptidase (AEP)/legumain

    NARCIS (Netherlands)

    Sexton, Kelly B.; Witte, Martin D.; Blum, Galia; Bogyo, Matthew

    2007-01-01

    Asparaginyl endopeptidase (AEP), also known as legumain, is a cysteine protease that has been ascribed roles in antigen presentation yet its exact role in human biology remains poorly understood. We report here, the use of a positional scanning combinatorial library of peptide AOMKs containing a P1

  3. Schistosome asparaginyl endopeptidase (legumain) is not essential for cathepsin B1 activation in vivo.

    Science.gov (United States)

    Krautz-Peterson, Greice; Skelly, Patrick J

    2008-05-01

    Schistosomes are parasitic platyhelminths that constitute an important public health problem. Adult parasites live in the vasculature of their vertebrate hosts where they consume blood. Ingested blood proteins are degraded by a proteolytic cascade. One of the best characterized schistosome proteases is cathepsin B1 (SmCB1 or Sm31). This protein is synthesized as a large 38 kDa precursor form which is proteolytically cleaved to yield a mature, active 31 kDa enzyme. A second schistosome protease--the asparaginyl endopeptidase SmAE (also known as Sm32, or schistosome legumain), has been proposed to proteolytically convert the 38 kDa precursor SmCB1 into its mature form. Recombinant activated SmAE has been shown to trans-process SmCB1 into the mature, catalytic form in vitro. In the present study, our aim was to test the hypothesis that in vivo SmAE likewise processes SmCB1 into its active form. To do this, expression of the SmAE gene was suppressed in adult Schistosoma mansoni using RNA interference (RNAi). The results of these experiments show that, even in the absence of detectable SmAE protein, SmCB1 is fully processed and active and support the assertion that SmAE is not essential to activate SmCB1 in vivo. The data indicate that our original hypothesis is incorrect and that SmAE is not pivotal in the in vivo conversion of cathepsin B1 into its mature, active form.

  4. Aza-peptidyl Michael acceptor and epoxide inhibitors--potent and selective inhibitors of Schistosoma mansoni and Ixodes ricinus legumains (asparaginyl endopeptidases).

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    Ovat, Asli; Muindi, Fanuel; Fagan, Crystal; Brouner, Michelle; Hansell, Elizabeth; Dvorák, Jan; Sojka, Daniel; Kopácek, Petr; McKerrow, James H; Caffrey, Conor R; Powers, James C

    2009-11-26

    Aza-peptide Michael acceptors and epoxides with the general structure of YCO-Ala-Ala-AAsn-trans-CH horizontal lineCHCOR and YCO-Ala-Ala-AAsn-EP-COR, respectively, are shown to be potent inhibitors of asparaginyl endopeptidases (legumains) from the bloodfluke, Schistosoma mansoni (SmAE), and the hard tick, Ixodes ricinus (IrAE). Structure-activity relationships (SARs) were determined for a set of 41 aza-peptide Michael acceptors and eight aza-peptide epoxides. Both enzymes prefer disubstituted amides to monosubstituted amides in the P1' position, and potency increased as we increased the hydrophobicity of the inhibitor in this position. Extending the inhibitor to P5 resulted in increased potency, especially against IrAE, and both enzymes prefer small over large hydrophobic residues at P2. Aza-peptide Michael acceptor inhibitors are more potent than aza-peptide epoxide inhibitors, and for some of these compounds, second-order inhibiton rate constants are the fastest yet discovered. Given the central functions of these enzymes in both parasites, the data presented here may facilitate the eventual design of selective antiparasitic drugs.

  5. Cloning and expression of mouse legumain, a lysosomal endopeptidase.

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    Chen, J M; Dando, P M; Stevens, R A; Fortunato, M; Barrett, A J

    1998-01-01

    Legumain, a recently discovered mammalian cysteine endopeptidase, was found in all mouse tissues examined, but was particularly abundant in kidney and placenta. The distribution in subcellular fractions of mouse and rat kidney showed a lysosomal localization, and activity was detectable only after the organelles were disrupted. Nevertheless, ratios of legumain activity to that of cathepsin B differed considerably between mouse tissues. cDNA encoding mouse legumain was cloned and sequenced, the deduced amino acid sequence proving to be 83% identical to that of the human protein [Chen, Dando, Rawlings, Brown, Young, Stevens, Hewitt, Watts and Barrett (1997) J. Biol. Chem. 272, 8090-8098]. Recombinant mouse legumain was expressed in human embryonic kidney 293 cells by use of a vector containing a cytomegalovirus promoter. The recombinant enzyme was partially purified and found to be an asparagine-specific endopeptidase closely similar to naturally occurring pig kidney legumain. PMID:9742219

  6. Activation of asparaginyl endopeptidase leads to Tau hyperphosphorylation in Alzheimer disease.

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    Basurto-Islas, Gustavo; Grundke-Iqbal, Inge; Tung, Yunn Chyn; Liu, Fei; Iqbal, Khalid

    2013-06-14

    Neurofibrillary pathology of abnormally hyperphosphorylated Tau is a key lesion of Alzheimer disease and other tauopathies, and its density in the brain directly correlates with dementia. The phosphorylation of Tau is regulated by protein phosphatase 2A, which in turn is regulated by inhibitor 2, I2(PP2A). In acidic conditions such as generated by brain ischemia and hypoxia, especially in association with hyperglycemia as in diabetes, I2(PP2A) is cleaved by asparaginyl endopeptidase at Asn-175 into the N-terminal fragment (I2NTF) and the C-terminal fragment (I2CTF). Both I2NTF and I2CTF are known to bind to the catalytic subunit of protein phosphatase 2A and inhibit its activity. Here we show that the level of activated asparaginyl endopeptidase is significantly increased, and this enzyme and I2(PP2A) translocate, respectively, from neuronal lysosomes and nucleus to the cytoplasm where they interact and are associated with hyperphosphorylated Tau in Alzheimer disease brain. Asparaginyl endopeptidase from Alzheimer disease brain could cleave GST-I2(PP2A), except when I2(PP2A) was mutated at the cleavage site Asn-175 to Gln. Finally, an induction of acidosis by treatment with kainic acid or pH 6.0 medium activated asparaginyl endopeptidase and consequently produced the cleavage of I2(PP2A), inhibition of protein phosphatase 2A, and hyperphosphorylation of Tau, and the knockdown of asparaginyl endopeptidase with siRNA abolished this pathway in SH-SY5Y cells. These findings suggest the involvement of brain acidosis in the etiopathogenesis of Alzheimer disease, and asparaginyl endopeptidase-I2(PP2A)-protein phosphatase 2A-Tau hyperphosphorylation pathway as a therapeutic target.

  7. Cystatin M/E is a high affinity inhibitor of cathepsin V and cathepsin L by a reactive site that is distinct from the legumain-binding site. A novel clue for the role of cystatin M/E in epidermal cornification.

    NARCIS (Netherlands)

    Cheng, T.; Hitomi, K.; Vlijmen-Willems, I.M.J.J. van; Jongh, G.J. de; Yamamoto, K.; Nishi, K.; Watts, C.; Reinheckel, T.; Schalkwijk, J.; Zeeuwen, P.L.J.M.

    2006-01-01

    Cystatin M/E is a high affinity inhibitor of the asparaginyl endopeptidase legumain, and we have previously reported that both proteins are likely to be involved in the regulation of stratum corneum formation in skin. Although cystatin M/E contains a predicted binding site for papain-like cysteine p

  8. Protease activity of legumain is inhibited by an increase of cystatin E/M in the DJ-1-knockout mouse spleen, cerebrum and heart

    Directory of Open Access Journals (Sweden)

    Takuya Yamane

    2017-03-01

    Full Text Available Legumain (EC 3.4.22.34 is an asparaginyl endopeptidase. Legumain activity has been detected in various mouse tissues including the kidney, spleen and epididymis. Legumain is overexpressed in the majority of human solid tumors and transcription of the legumain gene is regulated by the p53 tumor suppressor in HCT116 cells. The legumain activity is also increased under acid conditions in Alzheimer's disease brains. DJ-1/PARK7, a cancer- and Parkinson's disease-associated protein, works as a coactivator to various transcription factors, including the androgen receptor, p53, PSF, Nrf2, SREBP and RREB1. Recently, we found that legumain expression, activation and cleavage of annexin A2 are regulated by DJ-1 through p53. In this study, we found that the expression levels of legumain mRNA were increased in the cerebrum, kidney, spleen, heart, lung, epididymis, stomach, small intestine and pancreas from DJ-1-knockout mice, although legumain activity levels were decreased in the cerebrum, spleen and heart from DJ-1-knockout mice. Furthermore, we found that cystatin E/M expression was increased in the spleen, cerebrum and heart from DJ-1-knockout mice. These results suggest that reduction of legumain activity is caused by an increase of cystatin E/M expression in the spleen, cerebrum and heart from DJ-1-knockout mice.

  9. Functional expression and characterization of Schistosoma mansoni cathepsin B and its trans-activation by an endogenous asparaginyl endopeptidase.

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    Sajid, Mohammed; McKerrow, James H; Hansell, Elizabeth; Mathieu, Mary A; Lucas, Kimberley D; Hsieh, Ivy; Greenbaum, Doron; Bogyo, Matthew; Salter, Jason P; Lim, Kee C; Franklin, Christopher; Kim, Jea-Hyoun; Caffrey, Conor R

    2003-09-01

    Peptidases are essential for the establishment and survival of the medically important parasite, Schistosoma mansoni. This helminth expresses a number of gut-associated peptidases that degrade host blood proteins, including hemoglobin, as a means of nutrition. Using irreversible affinity probes, we demonstrate that S. mansoni cathepsin B-like endopeptidase 1 (SmCB1) is the most abundant papain family cysteine peptidase in both the parasite gut and somatic extracts. SmCB1 zymogen (SmCB1pm) was functionally expressed in Pichia pastoris (4-11mgl(-1)). Monospecific and immunoselected antibodies raised against SmCB1pm localized the enzyme exclusively to the gut lumen and surrounding gastrodermis of adult worms. Recombinant SmCB1pm was unable to catalyze its activation, even at low pH. However, recombinant S. mansoni asparaginyl endopeptidase (SmAE), another gut-associated cysteine peptidase, processed and activated SmCB1pm in trans. Consistent with the known specificity of AEs, processing occurred on the carboxyl side of an asparagine residue, two residues upstream of the start of the mature SmCB1 sequence. The remaining pro-region dipeptide was removed by rat cathepsin C (dipeptidyl-peptidase I)-an action conceivably performed by an endogenous cathepsin C in vivo. The activated recombinant SmCB1 is biochemically identical to the native enzyme with respect to dipeptidyl substrate kinetics and pH profiles. Also, the serum proteins, hemoglobin, serum albumin, IgG, and alpha-2 macroglobulin were efficiently degraded. Further, a novel application of an assay to measure the peptidyl carboxypeptidase activity of SmCB1 and other cathepsins B was developed using the synthetic substrate benzoyl-glycinyl-histidinyl-leucine (Bz-Gly-His-Leu). This study characterizes the major digestive cysteine peptidase in schistosomes and defines novel trans-processing events required to activate the SmCB1 zymogen in vitro which may facilitate the digestive process in vivo.

  10. Molecular cloning and characterization of Vigna mungo processing enzyme 1 (VmPE-1), an asparaginyl endopeptidase possibly involved in post-translational processing of a vacuolar cysteine endopeptidase (SH-EP).

    Science.gov (United States)

    Okamoto, T; Minamikawa, T

    1999-01-01

    Asparaginyl endopeptidase is a cysteine endopeptidase that has strict substrate specificity toward the carboxy side of asparagine residues. Vigna mungo processing enzyme 1, termed VmPE-1, occurs in the cotyledons of germinated seeds of V. mungo, and is possibly involved in the post-translational processing of a vacuolar cysteine endopeptidase, designated SH-EP, which degrades seed storage protein. VmPE-1 also showed a substrate specificity to asparagine residues, and its enzymatic activity was inhibited by NEM but not E-64. In addition, purified VmPE-1 had a potential to process the recombinant SH-EP precursor to its intermediate in vitro. cDNA clones for VmPE-1 and its homologue, named VmPE-1A, were identified and sequenced, and their expressions in the cotyledons of V. mungo seedlings and other organs were investigated. VmPE-1 mRNA and SH-EP mRNA were expressed in germinated seeds at the same stage of germination although the enzymatic activity of VmPE-1 rose prior to that of SH-EP. The level of VmPE-1A mRNA continued increasing as germination proceeded. In roots, stems and leaves of fully grown plants, and in hypocotyls, VmPE-1 and VmPE-1A were little expressed. We discuss possible functions of VmPE-1 and VmPE-1A in the cotyledons of germinated seeds.

  11. Glycosylation is important for legumain localization and processing to active forms but not for cystatin E/M inhibitory functions.

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    Lunde, Ngoc Nguyen; Haugen, Mads Haugland; Bodin Larsen, Kristina Broe; Damgaard, Ingrid; Pettersen, Solveig J; Kasem, Roya; Rut, Wioletta; Drag, Marcin; Poreba, Marcin; Johansen, Harald Thidemann; Solberg, Rigmor

    2017-08-01

    The asparaginyl endopeptidase legumain and its inhibitor cystatin E/M are endogenously glycosylated. However, little is known about the nature of the carbohydrate groups and whether they affect the functions of these proteins. In this study both glycosylated and unglycosylated forms of legumain and cystatin E/M were studied. HEK293 cell lines stably over-expressing legumain or cystatin E/M, and HCT116 cells were used as cell models, and mature legumain was purified from bovine kidneys. To obtain unglycosylated proteins, cells were treated with tunicamycin, an inhibitor of N-linked glycosylation, whereas PNGase F and Endo H were used to characterize the glycosylation types. Cells were incubated with glycosylated, unglycosylated proteins and/or legumain selective activity-based probe, and legumain and/or cystatin E/M was studied by activity measurement, ELISA or immunoblotting in cell lysates or conditioned media. Legumain and probe in whole cells were studied by immunofluorescence. The carbohydrates on legumain were shown to be of the hybrid or high mannose type, whereas cystatin E/M was characterized as complex mannose-linked. While glycosylated prolegumain was able to autoactivate, the unglycosylated form was not, and addition of glycosaminoglycans did not facilitate autoactivation of unglycosylated prolegumain. Glycosylated prolegumain was internalized and processed to the mature active form, but no internalization of unglycosylated prolegumain was observed. A Cy5-labelled legumain specific activity-based probe (MP-L09) was synthesized and shown to be a novel tool to study intracellular legumain. Also, internalization of mature legumain (36 kDa) was visualized both alone and complexed with probe. Contrary to the importance of legumain glycosylation, both glycosylated and unglycosylated cystatin E/M showed similar capacity to inhibit legumain. In conclusion, glycosylation of prolegumain is necessary for correct processing to active forms and internalization

  12. Identification and possible roles of three types of endopeptidase from germinated wheat seeds.

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    Sutoh, K; Kato, H; Minamikawa, T

    1999-10-01

    Little or no endopeptidase activity was detected in extracts of dry mature wheat seeds, but when they were allowed to imbibe water in darkness, the activity expressed per seedling increased notably after d 1, reached a maximum on d 3 and then decreased. Two major endopeptidases, named WEP-1 and WEP-2, were present in the 50-70% saturated ammonium sulfate fraction of d-3 seedlings, and could be separated by hydrophobic column chromatography. WEP-1 was further purified and identified as a 31-kDa polypeptide that was immunoreactive to antiserum raised against REP-1, a major rice cysteine endopeptidase. Experiments with proteinase inhibitors revealed that WEP-1 and WEP-2 are cysteine and serine endopeptidases, respectively. The two enzymes differed in substrate specificity, pH dependence, and the ability to digest major wheat seed proteins. Determination of its amino-terminal amino acid sequence indicated the similarity of WEP-1 to other cereal cysteine endopeptidases which are involved in the digestion of seed storage proteins. The expression of WEP-1 in de-embryonated seeds was induced in the presence of gibberellic acid and its effect was eliminated by abscisic acid. In addition to WEP-1 and WEP-2, a legumain-like asparaginyl endopeptidase was identified in the extract of seedlings on hydrophobic chromatography. The asparaginyl endopeptidase may function in the early step of mobilization of wheat storage proteins in germinated seeds.

  13. Nuclear legumain activity in colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Mads H Haugen

    Full Text Available The cysteine protease legumain is involved in several biological and pathological processes, and the protease has been found over-expressed and associated with an invasive and metastatic phenotype in a number of solid tumors. Consequently, legumain has been proposed as a prognostic marker for certain cancers, and a potential therapeutic target. Nevertheless, details on how legumain advances malignant progression along with regulation of its proteolytic activity are unclear. In the present work, legumain expression was examined in colorectal cancer cell lines. Substantial differences in amounts of pro- and active legumain forms, along with distinct intracellular distribution patterns, were observed in HCT116 and SW620 cells and corresponding subcutaneous xenografts. Legumain is thought to be located and processed towards its active form primarily in the endo-lysosomes; however, the subcellular distribution remains largely unexplored. By analyzing subcellular fractions, a proteolytically active form of legumain was found in the nucleus of both cell lines, in addition to the canonical endo-lysosomal residency. In situ analyses of legumain expression and activity confirmed the endo-lysosomal and nuclear localizations in cultured cells and, importantly, also in sections from xenografts and biopsies from colorectal cancer patients. In the HCT116 and SW620 cell lines nuclear legumain was found to make up approximately 13% and 17% of the total legumain, respectively. In similarity with previous studies on nuclear variants of related cysteine proteases, legumain was shown to process histone H3.1. The discovery of nuclear localized legumain launches an entirely novel arena of legumain biology and functions in cancer.

  14. Legumain Regulates Differentiation Fate of Human Bone Marrow Stromal Cells and Is Altered in Postmenopausal Osteoporosis.

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    Jafari, Abbas; Qanie, Diyako; Andersen, Thomas L; Zhang, Yuxi; Chen, Li; Postert, Benno; Parsons, Stuart; Ditzel, Nicholas; Khosla, Sundeep; Johansen, Harald Thidemann; Kjærsgaard-Andersen, Per; Delaisse, Jean-Marie; Abdallah, Basem M; Hesselson, Daniel; Solberg, Rigmor; Kassem, Moustapha

    2017-02-14

    Secreted factors are a key component of stem cell niche and their dysregulation compromises stem cell function. Legumain is a secreted cysteine protease involved in diverse biological processes. Here, we demonstrate that legumain regulates lineage commitment of human bone marrow stromal cells and that its expression level and cellular localization are altered in postmenopausal osteoporotic patients. As shown by genetic and pharmacological manipulation, legumain inhibited osteoblast (OB) differentiation and in vivo bone formation through degradation of the bone matrix protein fibronectin. In addition, genetic ablation or pharmacological inhibition of legumain activity led to precocious OB differentiation and increased vertebral mineralization in zebrafish. Finally, we show that localized increased expression of legumain in bone marrow adipocytes was inversely correlated with adjacent trabecular bone mass in a cohort of patients with postmenopausal osteoporosis. Our data suggest that altered proteolytic activity of legumain in the bone microenvironment contributes to decreased bone mass in postmenopausal osteoporosis.

  15. Legumain Regulates Differentiation Fate of Human Bone Marrow Stromal Cells and Is Altered in Postmenopausal Osteoporosis

    DEFF Research Database (Denmark)

    Jafari Kermani, Abbas; Qanie, Diyako; Andersen, Thomas L

    2017-01-01

    Secreted factors are a key component of stem cell niche and their dysregulation compromises stem cell function. Legumain is a secreted cysteine protease involved in diverse biological processes. Here, we demonstrate that legumain regulates lineage commitment of human bone marrow stromal cells...

  16. Asparaginyl deamidation in two glutamate dehydrogenase isoenzymes from Saccharomyces cerevisiae.

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    DeLuna, Alexander; Quezada, Héctor; Gómez-Puyou, Armando; González, Alicia

    2005-03-25

    The non-enzymatic deamidation of asparaginyl residues is a major source of spontaneous damage of several proteins under physiological conditions. In many cases, deamidation and isoaspartyl formation alters the biological activity or stability of the native polypeptide. Rates of deamidation of particular residues depend on many factors including protein structure and solvent exposure. Here, we investigated the spontaneous deamidation of the two NADP-glutamate dehydrogenase isoenzymes from Saccharomyces cerevisiae, which have different kinetic properties and are differentially expressed in this yeast. Our results show that Asn54, present in Gdh3p but missing in the GDH1-encoded homologue, is readily deamidated in vitro under alkaline conditions. Relative to the native enzyme, deamidated Gdh3p shows reduced protein stability. The different deamidation rates of the two isoenzymes could explain to some extent, the relative in vivo instability of the allosteric Gdh3p enzyme, compared to that of Gdh1p. It is thus possible that spontaneous asparaginyl modification could play a role in the metabolic regulation of ammonium assimilation and glutamate biosynthesis.

  17. Peptide-based MRI contrast agent and near-infrared fluorescent probe for intratumoral legumain detection.

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    Chen, Yu-Jen; Wu, Shou-Cheng; Chen, Chung-Yung; Tzou, Shey-Cherng; Cheng, Tian-Lu; Huang, Ying-Fang; Yuan, Shyng-Shiou; Wang, Yun-Ming

    2014-01-01

    Recent studies suggest that intratumoral legumain promotes tumorigenesis. To monitor legumain activity in tumors, we developed a new MRI contrast agent ([Gd-NBCB-TTDA-Leg(L)]) and a NIR fluorescence probe (CyTE777-Leg(L)-CyTE807). The MRI contrast agent was prepared by introduction of cyclobutyl and benzyl group residues to TTDA (3,6,10-tri(carboxymethyl)-3,6,10-triaza-dodecanedioic acid), followed by the attachment of a legumain-specific substrate peptide (Leg(L)). The NIR fluorescence probe was designed by conjugating two NIR fluorochromes (CyTE777 and CyTE807) with Leg(L). Peptide cleavage of the MRI contrast agent by legumain can increase its hydrophobicity and promote rotational correlation time (τ(R)). Peptide cleavage of the NIR probes by the legumain relieves the self quench of the probe. Peptide cleavage of the MRI contrast agent and the NIR fluorescence probe by legumain were confirmed by T1 relaxometric studies and by fluorescence studies, respectively. In vivo MR images showed that [Gd-NBCB-TTDA-Leg(L)] attained 55.3 fold (254.2% versus 4.6%, at 2.0 h post-injection) higher imaging enhancement, as compared with control contrast agent bearing a noncleaveable peptide ([Gd-NBCB-TTDA-Leg(D)], in the CT-26 (legumain(+)) tumors. Similarly, optical imaging probe CyTE777-Leg(L)-CyTE807 attained 15.2 fold (3.34 × 10(9) photons/min versus 0.22 × 10(9) photons/min, at 24.0 h post-injection) higher imaging enhancement in the CT-26 (legumain(+)) tumors, compared to a NIR control probe (CyTE777-Leg(D)-CyTE807). These data indicate that the [Gd-NBCB-TTDA-Leg(L)] and the CyTE777-Leg(L)-CyTE807 probes may be promising tools to image the legumain-expressing cancers for diagnoses and targeted treatments.

  18. Characterization of the legumains encoded by the genome of Theobroma cacao L.

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    Santana, Juliano Oliveira; Freire, Laís; de Sousa, Aurizangela Oliveira; Fontes Soares, Virgínia Lúcia; Gramacho, Karina Peres; Pirovani, Carlos Priminho

    2016-01-01

    Legumains are cysteine proteases related to plant development, protein degradation, programmed cell death, and defense against pathogens. In this study, we have identified and characterized three legumains encoded by Theobroma cacao genome through in silico analyses, three-dimensional modeling, genetic expression pattern in different tissues and as a response to the inoculation of Moniliophthora perniciosa fungus. The three proteins were named TcLEG3, TcLEG6, and TcLEG9. Histidine and cysteine residue which are part of the catalytic site were conserved among the proteins, and they remained parallel in the loop region in the 3D modeling. Three-dimensional modeling showed that the propeptide, which is located in the terminal C region of legumains blocks the catalytic cleft. Comparing dendrogram data with the relative expression analysis, indicated that TcLEG3 is related to the seed legumain group, TcLEG6 is related with the group of embryogenesis activities, and protein TcLEG9, with processes regarding the vegetative group. Furthermore, the expression analyses proposes a significant role for the three legumains during the development of Theobroma cacao and in its interaction with M. perniciosa. Copyright © 2015 Universidade Estadual de Santa Cruz, CNPJ: 40738999/0001-95. Published by Elsevier Masson SAS.. All rights reserved.

  19. Development of Activity Based Probes For The Study of Legumain In Cancer

    Science.gov (United States)

    Ortega, A.

    2010-12-01

    Proteases are enzymes, whose primary function is to cleave the peptide bonds of substrates. These enzymes are classified into five sub-families: cysteine, serine, threonine, metallo and aspartic. Legumain is a cysteine protease found primarily in lysosomes . It was initially identified in plants, but later found to play a role in antigen presentation in eukaryotic cells. Recent studies have shown that not only is legumain up-regulated in various human cancers, but also plays an important role in the growth and development of a tumor. Here we describe the development of an activity based probe, LE28, which will be a useful tool to aid in understanding how legumain contributes to tumorigenesis.

  20. Rice bifunctional phytocystatin is a dual modulator of legumain and papain-like proteases.

    Science.gov (United States)

    Christoff, Ana Paula; Passaia, Gisele; Salvati, Caroline; Alves-Ferreira, Márcio; Margis-Pinheiro, Marcia; Margis, Rogerio

    2016-09-01

    Phytocystatins are well-known inhibitors of C1A cysteine proteinases. However, previous research has revealed legumain (C13) protease inhibition via a carboxy-extended phytocystatin. Among the 12 phytocystatins genes in rice, OcXII is the only gene possessing this carboxy-terminal extension. The specific legumain inhibition activity was confirmed, in our work, using a recombinant OcXII harboring only the carboxy-terminal domain and this part did not exhibit any effect on papain-like activities. Meanwhile, rice plants silenced at the whole OcXII gene presented higher legumain and papain-like proteolytic activities, resulting in a faster initial seedling growth. However, when germinated under stressful alkaline conditions, OcXII-silenced plants exhibited impaired root formation and delayed shoot growth. Interestingly, the activity of OcXII promoter gene was detected in the rice seed scutellum region, and decreases with seedling growth. Seeds from these plants also exhibited slower growth at germination under ABA or alkaline conditions, while maintaining very high levels of OcXII transcriptional activation. This likely reinforces the proteolytic control necessary for seed germination and growth. In addition, increased legumain activity was detected in OcXII RNAi plants subjected to a fungal elicitor. Overall, the results of this study highlight the association of OcXII with not only plant development processes, but also with stress response pathways. The results of this study reinforce the bifunctional ability of carboxy-extended phytocystatins in regulating legumain proteases via its carboxy-extended domain and papain-like proteases by its amino-terminal domain.

  1. The crystal structure of asparaginyl-tRNA synthetase from Thermus thermophilus and its complexes with ATP and asparaginyl-adenylate: the mechanism of discrimination between asparagine and aspartic acid.

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    Berthet-Colominas, C; Seignovert, L; Härtlein, M; Grotli, M; Cusack, S; Leberman, R

    1998-01-01

    The crystal structure of Thermus thermophilus asparaginyl-tRNA synthetase has been solved by multiple isomorphous replacement and refined at 2.6 A resolution. This is the last of the three class IIb aminoacyl-tRNA synthetase structures to be determined. As expected from primary sequence comparisons, there are remarkable similarities between the tertiary structures of asparaginyl-tRNA synthetase and aspartyl-tRNA synthetase, and most of the active site residues are identical except for three key differences. The structure at 2.65 A of asparaginyl-tRNA synthetase complexed with a non-hydrolysable analogue of asparaginyl-adenylate permits a detailed explanation of how these three differences allow each enzyme to discriminate between their respective and very similar amino acid substrates, asparagine and aspartic acid. In addition, a structure of the complex of asparaginyl-tRNA synthetase with ATP shows exactly the same configuration of three divalent cations as previously observed in the seryl-tRNA synthetase-ATP complex, showing that this a general feature of class II synthetases. The structural similarity of asparaginyl- and aspartyl-tRNA synthetases as well as that of both enzymes to the ammonia-dependent asparagine synthetase suggests that these three enzymes have evolved relatively recently from a common ancestor. PMID:9582288

  2. Low-level internalization of cystatin E/M affects legumain activity and migration of melanoma cells.

    Science.gov (United States)

    Wallin, Hanna; Apelqvist, Jenny; Andersson, Freddi; Ekström, Ulf; Abrahamson, Magnus

    2017-09-01

    The ratio between proteases and their inhibitors is unbalanced in cancer. The cysteine protease inhibitor cystatin C is internalized by some cancer cells, which affects cellular properties. Here we aimed to investigate if uptake of cystatin C and the related inhibitor cystatin E/M occur in melanoma cell lines and to evaluate to what extent the uptake affects the legumain activity that is typically increased in melanoma. First we studied the basic expression, secretion, and intracellular content of all type 2 cystatins as well as expression and activity of their possible target enzymes legumain and cathepsin B in MDA-MB-435S, A375, and C8161 melanoma cells. Legumain activity was measureable in all cell lines, and of the potential legumain inhibitors, cystatin C, E/M, and F, cystatin C was the one mainly produced. All cells internalized cystatin C added to culture media, leading to increased intracellular cystatin C levels by 120-200%. Cystatin E/M was internalized as well but at a modest rate. The effects on intracellular legumain activity were nevertheless pronounced, probably because the cells lacked this inhibitor, and its affinity for legumain is 100-fold higher than that of cystatin C. Likewise, the low-degree uptake resulted in reduced migration and invasion of A375 cells in Matrigel to an extent comparable with the W106F variant of cystatin C with optimal uptake properties and resulting in much higher intracellular levels. Thus, cystatin E/M appears to be a good candidate to efficiently down-regulate the increased legumain activity, possibly important for the malignant phenotype of melanoma cells. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Host FIH-Mediated Asparaginyl Hydroxylation of Translocated Legionella pneumophila Effectors

    Science.gov (United States)

    Price, Christopher; Merchant, Michael; Jones, Snake; Best, Ashley; Von Dwingelo, Juanita; Lawrenz, Matthew B.; Alam, Nawsad; Schueler-Furman, Ora; Kwaik, Yousef A.

    2017-01-01

    FIH-mediated post-translational modification through asparaginyl hydroxylation of eukaryotic proteins impacts regulation of protein-protein interaction. We have identified the FIH recognition motif in 11 Legionella pneumophila translocated effectors, YopM of Yersinia, IpaH4.5 of Shigella and an ankyrin protein of Rickettsia. Mass spectrometry analyses of the AnkB and AnkH effectors of L. pneumophila confirm their asparaginyl hydroxylation. Consistent with localization of the AnkB effector to the Legionella-containing vacuole (LCV) membrane and its modification by FIH, our data show that FIH and its two interacting proteins, Mint3 and MT1-MMP are acquired by the LCV in a Dot/Icm type IV secretion-dependent manner. Chemical inhibition or RNAi-mediated knockdown of FIH promotes LCV-lysosomes fusion, diminishes decoration of the LCV with polyubiquitinated proteins, and abolishes intra-vacuolar replication of L. pneumophila. These data show acquisition of the host FIH by a pathogen-containing vacuole and that asparaginyl-hydroxylation of translocated effectors is indispensable for their function. PMID:28321389

  4. A novel serine protease with caspase- and legumain-like activities from edible basidiomycete Flammulina velutipes.

    Science.gov (United States)

    Iketani, Aya; Nakamura, Mayumi; Suzuki, Yuya; Awai, Koichiro; Shioi, Yuzo

    2013-03-01

    A serine protease with caspase- and legumain-like activities from basidiocarps of the edible basidiomycete Flammulina velutipes was characterized. The protease was purified to near homogeneity by three steps of chromatography using acetyl-Tyr-Val-Ala-Asp-4-methylcoumaryl-7-amide (Ac-YVAD-MCA) as a substrate. The enzyme was termed FvSerP (F. velutipes serine protease). This enzyme activity was completely inhibited by the caspase-specific inhibitor, Ac-YVAD-CHO, as well as moderately inhibited by serine protease inhibitors. Based on the N-terminal sequence, the cDNA of FvSerP was identified. The deduced protease sequence was a peptide composed of 325 amino acids with a molecular mass of 34.5 kDa. The amino acid sequence of FvSerP showed similarity to neither caspases nor to the plant subtilisin-like serine protease with caspase-like activity called saspase. FvSerP shared identity to the functionally unknown genes from class of Agaricomycetes, with similarity to the peptidase S41 domain of a serine protease. It was thus concluded that this enzyme is likely a novel serine protease with caspase- and legumain-like activities belonging to the peptidase S41 family and distributed in the class Agaricomycetes. This enzyme possibly functions in autolysis, a type of programmed cell death that occurs in the later stages of development of basidiocarps with reference to their enzymatic functions.

  5. Heterologous expression and characterization of recombinant Lactococcus lactis neutral endopeptidase (Neprilysin)

    NARCIS (Netherlands)

    Lian, W; Wu, D; Konings, W.N; Mierau, I; Hersh, L.B

    1996-01-01

    A neutral endopeptidase (NEP) from Lactococcus lactis has recently been cloned and shown to contain high sequence homology with the human neutral endopeptidase, endopeptidase 24.11 (I. Mierau et al., J. Bacteriol. 175, 2087-2096, 1993). The gene for the neutral endopeptidase from L. lactis was clone

  6. Synthesis and Characteristics of an Aspartame Analogue, L-Asparaginyl L-3-Phenyllactic Acid Methyl Ester

    Institute of Scientific and Technical Information of China (English)

    Hu TAO; Da-Fu CUI; You-Shang ZHANG

    2004-01-01

    An aspartame analogue,L-asparaginyl L-3-phenyllactic acid methyl ester was synthesized with aspartic acid replaced by asparagine and peptide bond replaced by ester bond.The aspartic acid of aspartame could be replaced by asparagine as reported in the literature.In this analogue,the hydrogen ofamide group could still form a hydrogen bond with the oxygen of ester bond and the ester bond was isosteric with peptide bond.However,the product was not sweet,showing that the peptide bond could not be replaced by ester bond.The peptide C-N bond behaves as a double bond that is not free to rotate and the C,O,N and H atoms are in the same plane.The replacement of peptide bond by ester bond destroyed the unique conformation of peptide bond,resulting in the loss of sweet taste.

  7. On Blastocystis secreted cysteine proteases: a legumain-activated cathepsin B increases paracellular permeability of intestinal Caco-2 cell monolayers.

    Science.gov (United States)

    Nourrisson, C; Wawrzyniak, I; Cian, A; Livrelli, V; Viscogliosi, E; Delbac, F; Poirier, P

    2016-11-01

    Blastocystis spp. pathogenic potential remains unclear as these anaerobic parasitic protozoa are frequently isolated from stools of both symptomatic and asymptomatic subjects. In silico analysis of the whole genome sequence of Blastocystis subtype 7 revealed the presence of numerous proteolytic enzymes including cysteine proteases predicted to be secreted. To assess the potential impact of proteases on intestinal cells and gut function, we focused our study on two cysteine proteases, a legumain and a cathepsin B, which were previously identified in Blastocystis subtype 7 culture supernatants. Both cysteine proteases were produced as active recombinant proteins. Activation of the recombinant legumain was shown to be autocatalytic and triggered by acidic pH, whereas proteolytic activity of the recombinant cathepsin B was only recorded after co-incubation with the legumain. We then measured the diffusion of 4-kDa FITC-labelled dextran across Caco-2 cell monolayers following exposition to either Blastocystis culture supernatants or each recombinant protease. Both Blastocystis culture supernatants and recombinant activated cathepsin B induced an increase of Caco-2 cell monolayer permeability, and this effect was significantly inhibited by E-64, a specific cysteine protease inhibitor. Our results suggest that cathepsin B might play a role in pathogenesis of Blastocystis by increasing intestinal cell permeability.

  8. Alginic acid-coated chitosan nanoparticles loaded with legumain DNA vaccine: effect against breast cancer in mice.

    Directory of Open Access Journals (Sweden)

    Ze Liu

    Full Text Available Legumain-based DNA vaccines have potential to protect against breast cancer. However, the lack of a safe and efficient oral delivery system restricts its clinical application. Here, we constructed alginic acid-coated chitosan nanoparticles (A.C.NPs as an oral delivery carrier for a legumain DNA vaccine. First, we tested its characteristic in acidic environments in vitro. DNA agarose electrophoresis data show that A.C.NPs protected DNA better from degradation in acidic solution (pH 1.5 than did chitosan nanoparticles (C.NPs. Furthermore, size distribution analysis showed that A.C.NPs tended to aggregate and form micrometer scale complexes in pH<2.7, while dispersing into nanoparticles with an increase in pH. Mice were intragastrically administrated A.C.NPs carrying EGFP plasmids and EGFP expression was detected in the intestinal Peyer's patches. Full-length legumain plasmids were loaded into different delivery carriers, including C.NPs, attenuated Salmonella typhimurium and A.C.NPs. A.C.NPs loaded with empty plasmids served as a control. Oral vaccination was performed in the murine orthotopic 4T1 breast cancer model. Our data indicate that tumor volume was significantly smaller in groups using A.C.NPs or attenuated Salmonella typhimurium as carriers. Furthermore, splenocytes co-cultured them with 4T1 cells pre-stimulated with CoCl2, which influenced the translocation of legumain from cytoplasm to plasma membrane, showed a 4.7 and 2.3 folds increase in active cytotoxic T lymphocytes (CD3(+/CD8(+/CD25(+ when treated with A.C.NPs carriers compared with PBS C.NPs. Our study suggests that C.NPs coated with alginic acid may be a safe and efficient tool for oral delivery of a DNA vaccine. Moreover, a legumain DNA vaccine delivered orally with A.C.NPs can effectively improve autoimmune response and protect against breast cancer in mice.

  9. Induced-fit Mechanism for Prolyl Endopeptidase

    Energy Technology Data Exchange (ETDEWEB)

    Li, Min; Chen, Changqing; Davies, David R.; Chiu, Thang K. (NIH); (LSU); (Chinese Aca. Sci.)

    2010-11-15

    Prolyl peptidases cleave proteins at proline residues and are of importance for cancer, neurological function, and type II diabetes. Prolyl endopeptidase (PEP) cleaves neuropeptides and is a drug target for neuropsychiatric diseases such as post-traumatic stress disorder, depression, and schizophrenia. Previous structural analyses showing little differences between native and substrate-bound structures have suggested a lock-and-key catalytic mechanism. We now directly demonstrate from seven structures of Aeromonus punctata PEP that the mechanism is instead induced fit: the native enzyme exists in a conformationally flexible opened state with a large interdomain opening between the {beta}-propeller and {alpha}/{beta}-hydrolase domains; addition of substrate to preformed native crystals induces a large scale conformational change into a closed state with induced-fit adjustments of the active site, and inhibition of this conformational change prevents substrate binding. Absolute sequence conservation among 28 orthologs of residues at the active site and critical residues at the interdomain interface indicates that this mechanism is conserved in all PEPs. This finding has immediate implications for the use of conformationally targeted drug design to improve specificity of inhibition against this family of proline-specific serine proteases.

  10. The TvLEGU-1, a Legumain-Like Cysteine Proteinase, Plays a Key Role in Trichomonas vaginalis Cytoadherence

    Directory of Open Access Journals (Sweden)

    Francisco Javier Rendón-Gandarilla

    2013-01-01

    Full Text Available The goal of this paper was to characterize a Trichomonas vaginalis cysteine proteinase (CP legumain-1 (TvLEGU-1 and determine its potential role as a virulence factor during T. vaginalis infection. A 30-kDa band, which migrates in three protein spots (pI~6.3, ~6.5, and ~6.7 with a different type and level of phosphorylation, was identified as TvLEGU-1 by one- and two-dimensional Western blot (WB assays, using a protease-rich trichomonad extract and polyclonal antibodies produced against the recombinant TvLEGU-1 (anti-TvLEGU-1r. Its identification was confirmed by mass spectrometry. Immunofluorescence, cell binding, and WB assays showed that TvLEGU-1 is upregulated by iron at the protein level, localized on the trichomonad surface and in lysosomes and Golgi complex, bound to the surface of HeLa cells, and was found in vaginal secretions. Additionally, the IgG and Fab fractions of the anti-TvLEGU-1r antibody inhibited trichomonal cytoadherence up to 45%. Moreover, the Aza-Peptidyl Michael Acceptor that inhibited legumain proteolytic activity in live parasites also reduced levels of trichomonal cytoadherence up to 80%. In conclusion, our data show that the proteolytic activity of TvLEGU-1 is necessary for trichomonal adherence. Thus, TvLEGU-1 is a novel virulence factor upregulated by iron. This is the first report that a legumain-like CP plays a role in a pathogen cytoadherence.

  11. Calcium regulates the expression of a Dictyostelium discoideum asparaginyl tRNA synthetase gene

    Indian Academy of Sciences (India)

    Jyoti K Jaiswal; Vidyanand Nanjundiah

    2003-12-01

    In a screen for calcium-regulated gene expression during growth and development of Dictyostelium discoideum we have identified an asparaginyl tRNA synthetase (ddAsnRS) gene, the second tRNA synthetase gene identified in this organism. The ddAsnRS gene shows many unique features. One, it is repressed by lowering cellular calcium, making it the first known calcium-regulated tRNA synthetase. Two, despite the calcium-dependence, its expression is unaltered during the cell cycle, making this the first D. discoideum gene to show a calcium-dependent but cell cycle phase-independent expression. Finally, the N-terminal domain of the predicted ddAsnRS protein shows higher sequence similarity to Glutaminyl tRNA synthetases than to other Asn tRNA synthetases. These unique features of the AsnRS from this primitive eukaryote not only point to a novel mechanism regulating the components of translation machinery and gene expression by calcium, but also hint at a link between the evolution of GlnRS and AsnRS in eukaryotes.

  12. Changes in Endopeptidase Activity during Photosynthetic Declination in Rice Leaf

    Institute of Scientific and Technical Information of China (English)

    DENGZhi-rui; ZHANGRong-xian

    2004-01-01

    Two japonica rice varieties, Wuyujing 3 and 97-7, were used to study the changes in contents of soluble protein, free amino acids and endopeptidase activity, during photosynthetic declination. The content of soluble protein in flag leaf of cv.Wuyujing 3 was higher than that of cv. 97-7, but decreased rapidly in Wuyujing 3. Free amino acids in flag leaf and the thirteenth leaf of Wuyujing 3 started to increase 10 days before the turning point of photosynthetic declination (TPPD), while it occurred just 1-2 days before TPPD in the flag leaf and the thirteenth leaf of 97-7. During reversible phase of photosynthetic declination,endopeptidase activity remained at a low level and increased slightly only in the later part of this phase. Then it rose up rapidly at irreversible decline phase and reached a vety high level. For Wuyujing 3, the change in endopeptidase activity in the thirteenth leaf was parallel to that in flag leaf. However, for 97-7, the rapid increase of endopeptidase activity in the thirteenth leaf started later than that of flag leaf. The results implied that the rate of protein breakdown and conversion to transportable nitrogen in leaves of 97-7 was slower than that in leaves of Wuyujing 3 during photosynthetic declination and it led to relativeh" lower seed setting rate and fully filling grains rate in 97-7. This may be one of the important reasons why 97-7 could not bring the high yicld potentiality into play and the findings may be taken into consideration while breeding for high potential varieties in future.

  13. Changes in Endopeptidase Activity during Photosynthetic Declination in Rice Leaf

    Institute of Scientific and Technical Information of China (English)

    DENG Zhi-rui; ZHANG Rong-xian

    2004-01-01

    Two japonica rice varieties, Wuyujing 3 and 97-7, were used to study the changes in contents of soluble protein, free amino acids and endopeptidase activity during photosynthetic declination. The content of soluble protein in flag leaf of cv.Wuyujing 3 was higher than that of cv. 97-7, but decreased rapidly in Wuyujing 3. Free amino acids in flag leaf and the thirteenth leaf of Wuyujing 3 started to increase 10 days before the turning point of photosynthetic declination (TPPD), while it occurred just 1-2 days before TPPD in the flag leaf and the thirteenth leaf of 97-7. During reversible phase of photosynthetic declination,endopeptidase activity remained at a low level and increased slightly only in the later part of this phase. Then it rose up rapidly at irreversible decline phase and reached a very high level. For Wuyujing 3, the change in endopeptidase activity in the thirteenth leaf was parallel to that in flag leaf. However, for 97-7, the rapid increase of endopeptidase activity in the thirteenth leaf started later than that of flag leaf. The results implied that the rate of protein breakdown and conversion to transportable nitrogen in leaves of 97-7 was slower than that in leaves of Wuyujing 3 during photosynthetic declination and it led to relatively lower seed setting rate and fully filling grains rate in 97-7. This may be one of the important reasons why 97-7 could not bring the high yield potentiality into play and the findings may be taken into consideration while breeding for high potential varieties in future.

  14. Multiple forms of endopeptidase activity from jojoba seeds.

    Science.gov (United States)

    Wolf, M J; Storey, R D

    1990-01-01

    The cotyledons of 27 day post-germination jojoba seedlings (Simmondsia chinensis) contained five distinct endopeptidase activities separable by DEAE Bio-Gel and CM-cellulose ion exchange chromatography. The endopeptidases were purified 108- to 266-fold and their individuality was confirmed by activity-specific assays in native acrylamide gels along with differences in their Mr and catalytic properties. The five endopeptidases, which showed activity on model substrates and protein, were named EP Ia, EP Ib, EP II, EP III and EP IV. EP Ia was a serine proteinase with a pH optimum of ca 8 and Mr of 58,000. EP Ib, II and III were discrete cysteine proteinases showing pH optima of ca 6.8, 6.0 and 5.4 and Mr of 41,000, 47,000 and 35,000 respectively. EP IV was an aspartic acid proteinase with a ca pH optimum of 3.5 and Mr of 33,000.

  15. Specific catalysis of asparaginyl deamidation by carboxylic acids: kinetic, thermodynamic, and quantitative structure-property relationship analyses.

    Science.gov (United States)

    Connolly, Brian D; Tran, Benjamin; Moore, Jamie M R; Sharma, Vikas K; Kosky, Andrew

    2014-04-07

    Asparaginyl (Asn) deamidation could lead to altered potency, safety, and/or pharmacokinetics of therapeutic protein drugs. In this study, we investigated the effects of several different carboxylic acids on Asn deamidation rates using an IgG1 monoclonal antibody (mAb1*) and a model hexapeptide (peptide1) with the sequence YGKNGG. Thermodynamic analyses of the kinetics data revealed that higher deamidation rates are associated with predominantly more negative ΔS and, to a lesser extent, more positive ΔH. The observed differences in deamidation rates were attributed to the unique ability of each type of carboxylic acid to stabilize the energetically unfavorable transition-state conformations required for imide formation. Quantitative structure property relationship (QSPR) analysis using kinetic data demonstrated that molecular descriptors encoding for the geometric spatial distribution of atomic properties on various carboxylic acids are effective determinants for the deamidation reaction. Specifically, the number of O-O and O-H atom pairs on carboxyl and hydroxyl groups with interatomic distances of 4-5 Å on a carboxylic acid buffer appears to determine the rate of deamidation. Collectively, the results from structural and thermodynamic analyses indicate that carboxylic acids presumably form multiple hydrogen bonds and charge-charge interactions with the relevant deamidation site and provide alignment between the reactive atoms on the side chain and backbone. We propose that carboxylic acids catalyze deamidation by stabilizing a specific, energetically unfavorable transition-state conformation of l-asparaginyl intermediate II that readily facilitates bond formation between the γ-carbonyl carbon and the deprotonated backbone nitrogen for cyclic imide formation.

  16. Determination of fluorescence-labeled asparaginyl-oligosaccharide in glycoprotein by reversed-phase ultraperformance liquid chromatography with electrospray ionization time-of-flight mass spectrometry.

    Science.gov (United States)

    Kurihara, Takamasa; Min, Jun Zhe; Toyo'oka, Toshimasa; Fukushima, Takeshi; Inagaki, Shinsuke

    2007-11-15

    Eight fluorescence reagents, i.e., DBD-F, NBD-F, DNS-Cl, NDA, PSC, FITC, Fmoc-Cl, and DMEQ-COCl, which are reactive to an amino functional group, were tested for the labeling of asparaginyl-oligosaccharides in a glycoprotein. Although the optimal reaction conditions and the fluorescence maximal wavelengths were different for each reagent, the highly sensitive fluorescence detection at the femtomole level of Disialo-Asn (a representative asparaginyl-oligosaccharide) was obtained from the labeling utilizing these reagents. Among them, PSC was the most reliable reagent in terms of detection sensitivity (approximately 3 fmol, signal-to-noise ratio of 5 (S/N = 5) on the chromatogram). However, the structural information could not be obtained from the fluorescence detection. Thus, the on-line determination of a real sample was carried out by UPLC-ESI-TOF-MS. The detection limit of the PSC-labeled Disialo-Asn by selected-ion chromatography was 58 fmol (S/N = 5). When the proposed procedure was applied to the determination of oligosaccharides in ovalbumin, 15 species of PSC-labeled oligosaccharides possessing Man, GlcNAc, and Gal units were identified from the UPLC-ESI-TOF-MS. The number of identified oligosaccharides was relatively greater than the method using Fmoc-Cl. Based on the ovalbumin results, the proposed labeling with PSC followed by UPLC-ESI-TOF-MS detection seems to be useful for the on-line asparaginyl-oligosaccharide analysis.

  17. Targeting cell-impermeable prodrug activation to tumor microenvironment eradicates multiple drug-resistant neoplasms.

    Science.gov (United States)

    Wu, Wenyuan; Luo, Yunping; Sun, Chengzao; Liu, Yuan; Kuo, Paul; Varga, Janos; Xiang, Rong; Reisfeld, Ralph; Janda, Kim D; Edgington, Thomas S; Liu, Cheng

    2006-01-15

    The tumor microenvironment is notably enriched with a broad spectrum of proteases. The proteolytic specificities of peptide substrates provide modular chemical tools for the rational design of cell-impermeable prodrugs that are specifically activated by proteases extracellularly in the tumor microenvironment. Targeting cell-impermeable prodrug activation to tumor microenvironment will significantly reduce drug toxicity to normal tissues. The activated prodrug attacks both tumor and stroma cells through a "bystander effect" without selectively deleting target-producing cells, therefore further minimizing resistance and toxicity. Here, we showed that legumain, the only asparaginyl endopeptidase of the mammalian genome, is highly expressed by neoplastic, stromal, and endothelial cells in solid tumors. Legumain is present extracellularly in the tumor microenvironment, associated with matrix as well as cell surfaces and functional locally in the reduced pH of the tumor microenvironment. A novel legumain-activated, cell-impermeable doxorubicin prodrug LEG-3 was designed to be activated exclusively in the tumor microenvironment. Upon administration, there is a profound increase of the end-product doxorubicin in nuclei of cells in tumors but little in other tissues. This tumor microenvironment-activated prodrug completely arrested growth of a variety of neoplasms, including multidrug-resistant tumor in vivo and significantly extended survival without evidence of myelosuppression or cardiac toxicity. The tumor microenvironment-activated prodrug design can be extended to other proteases and chemotherapeutic compounds and provides new potentials for the rational development of more effective functionally targeted cancer therapeutics.

  18. Toll-Like Receptor 4 Engagement Mediates Prolyl Endopeptidase Release from Airway Epithelia via Exosomes

    National Research Council Canada - National Science Library

    Szul, Tomasz; Bratcher, Preston E; Fraser, Kyle B; Kong, Michele; Tirouvanziam, Rabindra; Ingersoll, Sarah; Sztul, Elizabeth; Rangarajan, Sunil; Blalock, J Edwin; Xu, Xin; Gaggar, Amit

    2016-01-01

    .... Recently, we have characterized the enzyme prolyl endopeptidase (PE), a serine peptidase, as a critical protease in the generation of the neutrophil chemoattractant tripeptide Pro-Gly-Pro (PGP) from collagen...

  19. Separation and Characterization of Two Endopeptidases from Cotyledons of Germinating Vigna mungo Seeds.

    Science.gov (United States)

    Mitsuhashi, W; Koshiba, T; Minamikawa, T

    1986-03-01

    Two major endopeptidases were present in cotyledons of germinating Vigna mungo seeds, as detected by the zymogram after polyacrylamide gel electrophoresis. They were not detectable in cotyledons of dry seeds, but their intensities on the zymogram increased during germination. During incubation of detached cotyledons, however, the activities showed only a slight increase for 5 days. These two endopeptidases could be separated by Sephacryl S-200 column chromatography. One of them was found to be a serine-endopeptidase as judged by phenylmethylsulfonylfluoride and diisopropyl fluorophosphate inhibition. The other was a sulfhydryl-endopeptidase because of its dependency on 2-mercaptoethanol and inhibition by leupeptin, chymostatin, and antipain. Analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis indicatd that the two endopeptidases digested the Vigna mungo seed globulin subunits at different rates. The serine enzyme digested the 56 kilodalton subunit at first, but the sulfhydryl enzyme digested the 54 kilodalton peptide more efficiently than the 56 kilodalton peptide. The pattern of digestion of globulin by the combination of the serine- and sulfhydryl-endopeptidases was similar to that using crude enzyme extracts.

  20. Separation and Characterization of Two Endopeptidases from Cotyledons of Germinating Vigna mungo Seeds 1

    Science.gov (United States)

    Mitsuhashi, Wataru; Koshiba, Tomokazu; Minamikawa, Takao

    1986-01-01

    Two major endopeptidases were present in cotyledons of germinating Vigna mungo seeds, as detected by the zymogram after polyacrylamide gel electrophoresis. They were not detectable in cotyledons of dry seeds, but their intensities on the zymogram increased during germination. During incubation of detached cotyledons, however, the activities showed only a slight increase for 5 days. These two endopeptidases could be separated by Sephacryl S-200 column chromatography. One of them was found to be a serine-endopeptidase as judged by phenylmethylsulfonylfluoride and diisopropyl fluorophosphate inhibition. The other was a sulfhydryl-endopeptidase because of its dependency on 2-mercaptoethanol and inhibition by leupeptin, chymostatin, and antipain. Analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis indicatd that the two endopeptidases digested the Vigna mungo seed globulin subunits at different rates. The serine enzyme digested the 56 kilodalton subunit at first, but the sulfhydryl enzyme digested the 54 kilodalton peptide more efficiently than the 56 kilodalton peptide. The pattern of digestion of globulin by the combination of the serine- and sulfhydryl-endopeptidases was similar to that using crude enzyme extracts. Images Fig. 2 Fig. 3 Fig. 6 Fig. 7 PMID:16664675

  1. 应用杆状病毒表达系统在Sf9昆虫细胞中重组表达Legumain蛋白%Production of Legumain protein with baculovirus expression system in insect cell Sf9

    Institute of Scientific and Technical Information of China (English)

    李兴育; 张华; 李娟; 田冰玉

    2014-01-01

    目的 通过昆虫-杆状病毒表达系统表达获得Legumain蛋白,为进一步研究其在葡萄膜黑色素瘤中的作用建立基础.方法 实验研究.对2011年4月至2012年1月在陕西省眼科中心应用克隆Legumain蛋白基因,并将其基因片段插入pFastBac载体获得重组载体,转化大肠杆菌DH10Bac感受态细胞后得到重组Bacmid,转染昆虫Sf9细胞,Western Blotting印迹和SDS-PAGE检测重组蛋白的表达.结果 获得了Legumain蛋白的重组杆状病毒;Western Blotting印迹和SDS-PAGE分析表明,该重组杆状病毒感染昆虫Sf9细胞后表达Legumain蛋白,与预期结果一致.结论 通过昆虫-杆状病毒表达系统可成功获得Legumain蛋白,从而为进一步研究其在葡萄膜黑色素瘤侵袭与转移机制的作用奠定了工作基础.%Objective To obtain human Legumain protein with insect-baculovirus expression system,make foundation for the uveal melanoma study.Methods The gene encoding Legumain protein was cloned and inserted into the pFastBac vector,and the recombinant bacmid was generated after the E.coli DH10Bac competent cell was transformed by the recombinant pFastBac vector.The recombinant baculovirns was transfected into insect cell Sf9.Western Blotting and SDS-PAGE analysis of recombinant protein expression was performed.Results Recombinant baculovirns expressing Legumain protein was obtained.Western Blotting and SDS-PAGE analysis showed that Legumain protein was expressed when the Sf9 cells were infected by the recombinant baculovirus,which consistent with the expected results.Conclusions Legumain protein was obtained through insect-baculovirus expression system.Cloning and expression of Legumain protein provide the foundation for the mechanism of Legumain in the uveal melanoma invasion and metastasis.

  2. Homologous inhibitors from potato tubers of serine endopeptidases and metallocarboxypeptidases.

    Science.gov (United States)

    Hass, C M; Venkatakrishnan, R; Ryan, C A

    1976-06-01

    A potent polypeptide inhibitor of chymotrypsin has been purified from Russett Burbank potatoes. The inhibitor has no effect on bovine carboxypeptidases A or B but exhibits homology with a carboxypeptidase inhibitor that is also present in potato tubers. The chymotrypsin inhibitor has a molecular weight of approximately 5400 as estimated by gel filtration, amino acid analysis, and titration with chymotrypsin. The polypeptide chain consists of 49 amino acid residues, of which six are half-cystine, forming three disulfide bonds. Its size is similar to that of the carboxypeptidase inhibitor, which contains 39 amino acid residues and also has three disulfide bridges. In immunological double diffusion assays, the chymotrypsin inhibitor and the carboxypeptidase inhibitor do not crossreact; however, automatic Edman degradation of reduced and alkylated derivatives of the chymotrypsin inhibitor, yielding a partial sequence of 18 amino acid residues at the NH2-terminus, reveals a similarity in sequence to that of the carboxypeptidase inhibitor. Thus, inhibitors directed toward two distinct classes of proteases, the serine endopeptidases and the metallocarboxypeptidases, appear to have evolved from a common ancestor.

  3. Mutations of human NARS2, encoding the mitochondrial asparaginyl-tRNA synthetase, cause nonsyndromic deafness and Leigh syndrome.

    Directory of Open Access Journals (Sweden)

    Mariella Simon

    2015-03-01

    Full Text Available Here we demonstrate association of variants in the mitochondrial asparaginyl-tRNA synthetase NARS2 with human hearing loss and Leigh syndrome. A homozygous missense mutation ([c.637G>T; p.Val213Phe] is the underlying cause of nonsyndromic hearing loss (DFNB94 and compound heterozygous mutations ([c.969T>A; p.Tyr323*] + [c.1142A>G; p.Asn381Ser] result in mitochondrial respiratory chain deficiency and Leigh syndrome, which is a neurodegenerative disease characterized by symmetric, bilateral lesions in the basal ganglia, thalamus, and brain stem. The severity of the genetic lesions and their effects on NARS2 protein structure cosegregate with the phenotype. A hypothetical truncated NARS2 protein, secondary to the Leigh syndrome mutation p.Tyr323* is not detectable and p.Asn381Ser further decreases NARS2 protein levels in patient fibroblasts. p.Asn381Ser also disrupts dimerization of NARS2, while the hearing loss p.Val213Phe variant has no effect on NARS2 oligomerization. Additionally we demonstrate decreased steady-state levels of mt-tRNAAsn in fibroblasts from the Leigh syndrome patients. In these cells we show that a decrease in oxygen consumption rates (OCR and electron transport chain (ETC activity can be rescued by overexpression of wild type NARS2. However, overexpression of the hearing loss associated p.Val213Phe mutant protein in these fibroblasts cannot complement the OCR and ETC defects. Our findings establish lesions in NARS2 as a new cause for nonsyndromic hearing loss and Leigh syndrome.

  4. Presence and expression of hydrogenase specific C-terminal endopeptidases in cyanobacteria

    Directory of Open Access Journals (Sweden)

    Lindblad Peter

    2003-05-01

    Full Text Available Abstract Background Hydrogenases catalyze the simplest of all chemical reactions: the reduction of protons to molecular hydrogen or vice versa. Cyanobacteria can express an uptake, a bidirectional or both NiFe-hydrogenases. Maturation of those depends on accessory proteins encoded by hyp-genes. The last maturation step involves the cleavage of a ca. 30 amino acid long peptide from the large subunit by a C-terminal endopeptidase. Until know, nothing is known about the maturation of cyanobacterial NiFe-hydrogenases. The availability of three complete cyanobacterial genome sequences from strains with either only the uptake (Nostoc punctiforme ATCC 29133/PCC 73102, only the bidirectional (Synechocystis PCC 6803 or both NiFe-hydrogenases (Anabaena PCC 7120 prompted us to mine these genomes for hydrogenase maturation related genes. In this communication we focus on the presence and the expression of the NiFe-hydrogenases and the corresponding C-terminal endopeptidases, in the three strains mentioned above. Results We identified genes encoding putative cyanobacterial hydrogenase specific C-terminal endopeptidases in all analyzed cyanobacterial genomes. The genes are not part of any known hydrogenase related gene cluster. The derived amino acid sequences show only low similarity (28–41% to the well-analyzed hydrogenase specific C-terminal endopeptidase HybD from Escherichia coli, the crystal structure of which is known. However, computational secondary and tertiary structure modeling revealed the presence of conserved structural patterns around the highly conserved active site. Gene expression analysis shows that the endopeptidase encoding genes are expressed under both nitrogen-fixing and non-nitrogen-fixing conditions. Conclusion Anabaena PCC 7120 possesses two NiFe-hydrogenases and two hydrogenase specific C-terminal endopeptidases but only one set of hyp-genes. Thus, in contrast to the Hyp-proteins, the C-terminal endopeptidases are the only known

  5. cDNA cloning of porcine brain prolyl endopeptidase and identification of the active-site seryl residue

    Energy Technology Data Exchange (ETDEWEB)

    Rennex, D.; Hemmings, B.A.; Hofsteenge, J.; Stone, S.R. (Friedrich Miescher-Institut, Basel (Switzerland))

    1991-02-26

    Prolyl endopeptidase is a cytoplasmic serine protease. The enzyme was purified from porcine kidney, and oligonucleotides based on peptide sequences from this protein were used to isolate a cDNA clone from a porcine brain library. This clone contained the complete coding sequence of prolyl endopeptidase and encoded a polypeptide with a molecular mass of 80751 Da. The deduced amino acid sequence of prolyl endopeptidase showed no sequence homology with other known serine proteases. ({sup 3}H)Diisopropyl fluorophosphate was used to identify the active-site serine of prolyl endopeptidase. One labeled peptide was isolated and sequenced. The sequence surrounding the active-site serine was Asn-Gly-Gly-Ser-Asn-Gly-Gly. This sequence is different from the active-site sequences of other known serine proteases. This difference and the lack of overall homology with the known families of serine proteases suggest that prolyl endopeptidase represents a new type of serine protease.

  6. CELL DETACHMENT BY PROLYL-SPECIFIC ENDOPEPTIDASE FROM WOLFIPORIA COCOS

    Directory of Open Access Journals (Sweden)

    Katharina Cierpka

    2014-01-01

    Full Text Available As requirements for Advanced Therapy Medicinal Product (ATMP production differ from other production processes (e.g., therapeutic protein production, cell detachment is often a crucial step for the process success. In most cases, cell detachment is done enzymatically. Although many peptidases are established in cell culture in R&D, e.g., Trypsin as gold standard, many of them seem to be unsuitable in ATMP production processes. Therefore, the present study investigated a novel endopeptidase used in food biotechnology for its applicability in ATMP processes where cell detachment is needed. The Prolyl-specific Peptidase (PsP is of non-mammalian origin and considered as safe for humans. PsP was purified from the supernatant of the fungus Wolfiporia cocos. The isolation and purification resulted in an enzyme solution with 0.19 U mg-1 prolyl-specific activity. By in silico analysis it was confirmed that attachment-promoting proteins can be cleaved by PsP in a similar amount than with Trypsin. Further the proteolytic activity was determined for PsP and Trypsin by using the same enzymatic assay. Detachment with both enzymes was compared for cells used in typical therapeutic production processes namely a mesenchymal stem cell line (hMSC-TERT as a model for a cell therapeutic, Vero and MA104 cells used for viral therapeutic or vaccine production. The cell detachment experiments were performed with comparable enzyme activities (1.6 U mL-1. hMSC-TERT detachment was faster with PsP than with Trypsin. For Vero cells the detachment with PsP was not only faster but also more efficient. For MA104 cells the detachment rate with PsP was similar to Trypsin. For all cell types, detachment with PsP showed less influence on cell growth and metabolism compared to standard Trypsin.Thus, three cell types used in ATMP, viral therapeutics or vaccine production can be detached efficiently and gently with PsP. Therefore, PsP shows

  7. Synthesis and evaluation of heteroarylalanine diacids as potent and selective neutral endopeptidase inhibitors.

    Science.gov (United States)

    Glossop, Melanie S; Bazin, Richard J; Dack, Kevin N; Fox, David N A; MacDonald, Graeme A; Mills, Mark; Owen, Dafydd R; Phillips, Chris; Reeves, Keith A; Ringer, Tracy J; Strang, Ross S; Watson, Christine A L

    2011-06-01

    Heteroarylalanine derivatives 4 were designed as potential inhibitors of neutral endopeptidase (NEP EC 3.4.24.11). Selectivity over other zinc metalloproteinases was explored through occupation of the S2' subsite within NEP. Structural optimisation led to the identification of 5-phenyl oxazole 4f, a potent and selective NEP inhibitor. A crystal structure of the inhibitor bound complex is reported.

  8. Chromosomal Location by Use of Trisomics and New Alleles of an Endopeptidase in Zea Mays

    DEFF Research Database (Denmark)

    Nielsen, Gunnar Gissel; Scandalios, John G.

    1974-01-01

    An association was found earlier between the Ep1 gene locus coding for an endopeptidase and the endosperm color gene Y1 on chromosome 6 of Zea mays. By employing primary trisomics we have unequivocally placed the Ep1 gene on chromosome 6, closely linked to the Y1 locus. Additionally we describe new...

  9. Concurrent neutral endopeptidase and ACE inhibition in experimental heart failure: renal and hormonal effects

    DEFF Research Database (Denmark)

    Helin, K

    1993-01-01

    Neutral endopeptidase (NEP) inhibitors have been shown to strengthen the effects of endogenous atrial natriuretic peptide (ANP). It has been well documented that angiotensin I-converting enzyme (ACE) inhibitors act beneficially in chronic congestive heart failure (CHF). In the present study, renal...

  10. Inhibition of [gamma]-endorphin generating endopeptidase activity of rat brain by peptides: Structure activity relationship

    NARCIS (Netherlands)

    Lebouille, J.L.M.; Visser, W.H.; Hendriks, R.W.; Nispen, J.W. van; Greven, H.M.; Burbach, J.P.H.

    1985-01-01

    Gamma-Endorphin generating endopeptidase (gammaEGE) activity is an enzyme activity which converts beta-endorphin into gamma-endorphin and beta-endorphin-(18–31). The inhibitory potency on gammaEGE activity of neuropeptides and analogues or fragments of neuropeptides was tested. Dynorphin-(1–13) (IC5

  11. Endopeptidase Isoenzyme Characteristics in Cucumis sativus Leaves During Dark-induced Senescence

    Institute of Scientific and Technical Information of China (English)

    Peng Zhang; Fei Wang; Lie-Feng Zhang; Qi Rui; Lang-Lai Xu

    2007-01-01

    The changes and characteristics of endopeptidase (EP) isoenzymes in cucumber (Cucumis sativus L.) leaves during dark-induced senescence were investigated by activity staining after gradient-polyacrylamide gel electrophoresis (G-PAGE) containing co-polymerized gelatin as substrate. The results showed that both the chlorophyll and the protein contents of leaves were decreased, and the protein degradation was correlated with the increase of proteolytic activity during the course of leaf senescence. Meanwhile, nine cucumber endopeptidases isoenzymes (CEP) with 140, 120, 106, 94, 76, 55, 46, 39 and 35 kDa molecular weights were detected. Four of these, CEP2, 3, 4 and CEP9 appeared all the time, but the changes of the activity were different during incubation. Another four CEPs (CEP5, 6, 7 and CEP8) whose activities increased with dark-induced time were only detected in senescent leaves.Furthermore, the biochemical properties of these nine CEP were also characterized. All the CEPs had high activities from 35 ℃ to 45 ℃, and the optimum temperature was found to be 40 ℃. However, the activities of CEPs were not detected below 25 ℃ or over 60 ℃. The activity bands appeared at a wide range of pH from 5.0 to 9.0, but the optimum pH was found at 7.0. No CEPs were detected at pH 4 or pH 10. By inhibition analysis we concluded that CEP2,3, 4 and CEP9 were serine endopeptidases and CEP6 was a kind of cysteine protease. It is suggested that serine endopeptidases might play a major role in cucumber leaf senescence, and for the first time, six senescencerelated endopeptidases (CEP1, 5, 6, 7, 8 and 9) were found in cucumber leaves.

  12. Synthesis and Posttranslational Activation of Sulfhydryl-Endopeptidase in Cotyledons of Germinating Vigna mungo Seeds.

    Science.gov (United States)

    Mitsuhashi, W; Minamikawa, T

    1989-01-01

    A sulfhydryl-endopeptidase was purified as a 33 kilodalton (kD) mass polypeptide from cotyledons of Vigna mungo seedlings. Immunoblot analysis with antiserum made against the purified enzyme showed that the sulfhydryl-endopeptidase was synthesized only in the cotyledons during germination and that the amount of the enzyme increased until 4 days after imbibition and decreased thereafter. Next, an RNA fraction was prepared from cotyledons of 3 day old seedlings and translated in a wheat germ system. The synthesis of a 45 kD polypeptide was shown by the analysis of its translation products by immunoprecipitation with the antiserum to the endopeptidase and gel electrophoresis. When the RNA fraction was translated in the presence of canine microsomal membranes, a smaller polypeptide, having a 43 kD molecular mass, was detected as the translation product. When membrane-bound polysomes, but not free polysomes, prepared from cotyledons were used for translation in the wheat germ system, both the 43 and 45 kD polypeptides were synthesized. By incubation of a crude enzyme extract from cotyledons at 5 +/- 1 degrees C at neutral pH, the 43 kD polypeptide was sequentially cleaved to the 33 kD polypeptide via 39 and 36 kD intermediate polypeptides. The endopeptidase was activated simultaneously with the processing. Two-dimensional polyacrylamide gel electrophoresis showed that the 33 kD polypeptide was the fully activated form of the enzyme, whereas little or no activity was detected in other forms. From the present results, we postulate that the sulfhydryl-endopeptidase is first synthesized as the 45 kD precursor with a 2 kD signal peptide being cleaved, and that the 43 kD polypeptide is further cleaved to give the 33kD mature enzyme.

  13. Synthesis and Posttranslational Activation of Sulfhydryl-Endopeptidase in Cotyledons of Germinating Vigna mungo Seeds 1

    Science.gov (United States)

    Mitsuhashi, Wataru; Minamikawa, Takao

    1989-01-01

    A sulfhydryl-endopeptidase was purified as a 33 kilodalton (kD) mass polypeptide from cotyledons of Vigna mungo seedlings. Immunoblot analysis with antiserum made against the purified enzyme showed that the sulfhydryl-endopeptidase was synthesized only in the cotyledons during germination and that the amount of the enzyme increased until 4 days after imbibition and decreased thereafter. Next, an RNA fraction was prepared from cotyledons of 3 day old seedlings and translated in a wheat germ system. The synthesis of a 45 kD polypeptide was shown by the analysis of its translation products by immunoprecipitation with the antiserum to the endopeptidase and gel electrophoresis. When the RNA fraction was translated in the presence of canine microsomal membranes, a smaller polypeptide, having a 43 kD molecular mass, was detected as the translation product. When membrane-bound polysomes, but not free polysomes, prepared from cotyledons were used for translation in the wheat germ system, both the 43 and 45 kD polypeptides were synthesized. By incubation of a crude enzyme extract from cotyledons at 5 ± 1°C at neutral pH, the 43 kD polypeptide was sequentially cleaved to the 33 kD polypeptide via 39 and 36 kD intermediate polypeptides. The endopeptidase was activated simultaneously with the processing. Two-dimensional polyacrylamide gel electrophoresis showed that the 33 kD polypeptide was the fully activated form of the enzyme, whereas little or no activity was detected in other forms. From the present results, we postulate that the sulfhydryl-endopeptidase is first synthesized as the 45 kD precursor with a 2 kD signal peptide being cleaved, and that the 43 kD polypeptide is further cleaved to give the 33kD mature enzyme. Images Figure 1 Figure 2 Figure 4 Figure 5 Figure 6 PMID:16666526

  14. Neutral endopeptidase inhibition: could it have a role in the treatment of female sexual arousal disorder?

    Science.gov (United States)

    Angulo, Javier

    2010-05-01

    Female sexual arousal disorder (FSAD) is the inability to attain or maintain an adequate lubrication-swelling response of sexual excitement. The potentiation of vascular responses leading to increased blood flow in clitoris and vagina has represented the main focus in the pharmacological treatment of FSAD, including the evaluation of the type 5 phosphodiesterase (PDE5) inhibitors. However, due to a lack of clear efficacy, there is no approved pharmacotherapy for FSAD to date. In the present issue of the British Journal of Pharmacology, Wayman et al. show that the administration by intravenous or intravaginal routes of a novel neutral endopeptidase inhibitor, UK-414,445, results in enhanced genital blood flow responses to pelvic nerve stimulation in female rabbits, without significantly affecting blood pressure. Neutral endopeptidase inhibition, by preserving vasoactive peptides such as vasoactive intestinal polypeptide, raises the possibility of a new pharmacological approach to the treatment of FSAD.

  15. An intermolecular binding mechanism involving multiple LysM domains mediates carbohydrate recognition by an endopeptidase

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Jaslyn E. M. M. [Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus (Denmark); Midtgaard, Søren Roi [University of Copenhagen, Universitetsparken 5, 2100 Copenhagen (Denmark); Gysel, Kira [Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus (Denmark); Thygesen, Mikkel B.; Sørensen, Kasper K.; Jensen, Knud J. [University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); Stougaard, Jens; Thirup, Søren; Blaise, Mickaël, E-mail: mickael.blaise@cpbs.cnrs.fr [Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus (Denmark)

    2015-03-01

    The crystal and solution structures of the T. thermophilus NlpC/P60 d, l-endopeptidase as well as the co-crystal structure of its N-terminal LysM domains bound to chitohexaose allow a proposal to be made regarding how the enzyme recognizes peptidoglycan. LysM domains, which are frequently present as repetitive entities in both bacterial and plant proteins, are known to interact with carbohydrates containing N-acetylglucosamine (GlcNAc) moieties, such as chitin and peptidoglycan. In bacteria, the functional significance of the involvement of multiple LysM domains in substrate binding has so far lacked support from high-resolution structures of ligand-bound complexes. Here, a structural study of the Thermus thermophilus NlpC/P60 endopeptidase containing two LysM domains is presented. The crystal structure and small-angle X-ray scattering solution studies of this endopeptidase revealed the presence of a homodimer. The structure of the two LysM domains co-crystallized with N-acetyl-chitohexaose revealed a new intermolecular binding mode that may explain the differential interaction between LysM domains and short or long chitin oligomers. By combining the structural information with the three-dimensional model of peptidoglycan, a model suggesting how protein dimerization enhances the recognition of peptidoglycan is proposed.

  16. Glycyl endopeptidase from papaya latex: partial purification and use for production of fish gelatin hydrolysate.

    Science.gov (United States)

    Karnjanapratum, Supatra; Benjakul, Soottawat

    2014-12-15

    An aqueous two-phase system (ATPS) in combination with ammonium sulphate ((NH4)2SO4) precipitation was applied to fractionate glycyl endopeptidase from the papaya latex of Red Lady and Khack Dum cultivars. ATPS containing polyethylene glycol (PEG 2000 and 6000) and salts ((NH4)2SO4 and MgSO4) at different concentrations were used. Glycyl endopeptidase with high purification fold (PF) and yield was found in the salt-rich bottom phase of ATPS with 10%PEG 6000-10% (NH4)2SO4. When ATPS fraction from Red Lady cultivar was further precipitated with 40-60% saturation of (NH4)2SO4, PF of 2.1-fold with 80.23% yield was obtained. Almost all offensive odorous compounds, particularly benzyl isothiocyanate, were removed from partially purified glycyl endopeptidase (PPGE). The fish gelatin hydrolysates prepared using PPGE showed higher ABTS radical scavenging activity and less odour, compared with those of crude extract (CE). Thus antioxidative gelatin hydrolysate with negligible undesirable odour could be prepared with the aid of PPGE.

  17. Computer-aided lead optimization: improved small-molecule inhibitor of the zinc endopeptidase of botulinum neurotoxin serotype A.

    Directory of Open Access Journals (Sweden)

    Jing Tang

    Full Text Available Optimization of a serotype-selective, small-molecule inhibitor of botulinum neurotoxin serotype A (BoNTA endopeptidase is a formidable challenge because the enzyme-substrate interface is unusually large and the endopeptidase itself is a large, zinc-binding protein with a complex fold that is difficult to simulate computationally. We conducted multiple molecular dynamics simulations of the endopeptidase in complex with a previously described inhibitor (K(i (app of 7+/-2.4 microM using the cationic dummy atom approach. Based on our computational results, we hypothesized that introducing a hydroxyl group to the inhibitor could improve its potency. Synthesis and testing of the hydroxyl-containing analog as a BoNTA endopeptidase inhibitor showed a twofold improvement in inhibitory potency (K(i (app of 3.8+/-0.8 microM with a relatively small increase in molecular weight (16 Da. The results offer an improved template for further optimization of BoNTA endopeptidase inhibitors and demonstrate the effectiveness of the cationic dummy atom approach in the design and optimization of zinc protease inhibitors.

  18. Irreversible photolabeling of active site of neutral endopeptidase-24. 11 enkephalinase by azidothiorphan and (/sup 14/C)-azidothiorphan

    Energy Technology Data Exchange (ETDEWEB)

    Beaumont, A.; Hernandez, J.F.; Chaillet, P.; Crine, P.; Roques, B.P.

    1987-11-01

    Azidothiorphan and its (/sup 14/C)-labeled analogue have been developed as photoaffinity ligands for the active site of the neutral endopeptidase 24.11. In in vitro assays azidothiorphan inhibits the endopeptidase activity with a Ki of 0.75 nM. After ultraviolet irradiation the inhibitor binds irreversibly to the enzyme, and many factors suggest that the photolabeling occurs at the active site. The binding is accompanied by a loss of enzymatic activity, and the inclusion of the competitive inhibitor thiorphan protects the endopeptidase from this inactivation. In addition the binding of another competitive inhibitor (/sup 3/H)N-((R,S)-3-hydroxyaminocarbonyl-2-benzyl-1-oxopropyl)-glycine to the active site of endopeptidase-24.11 is inhibited after irradiation with azidothiorphan. Experiments with (/sup 14/C)-azidothiorphan have shown that very little nonspecific binding of inhibitor to enzyme occurs and the the labeled probe remains bound under denaturing conditions. Azidothiorphan has also been found to produce a long-lasting naloxone-reversible analgesia after intracerebroventricular administration. The results show that azidothiorphan should prove useful both for structural studies and for investigations on the synthesis and turnover of the neutral endopeptidase-24.11.

  19. The role of neutral endopeptidase in dogs with evolving congestive heart failure.

    Science.gov (United States)

    Margulies, K B; Barclay, P L; Burnett, J C

    1995-04-01

    Recent studies suggest that neurohumoral mechanisms including decreased renal responses to increases in atrial natriuretic factor (ANF) play a central role in the progression from asymptomatic cardiac dysfunction to advanced congestive heart failure (CHF) with sodium retention, vasoconstriction, and reduced exercise tolerance. Recognizing that neutral endopeptidase 24.11 degrades ANF and may be enhanced in CHF, we hypothesized that chronic neutral endopeptidase inhibition (NEP-I) would potentiate renal responses to exogenous ANF and alter the temporal evolution of sodium retention in evolving CHF by potentiation of increased endogenous ANF. We studied 13 conscious dogs with evolving CHF produced by rapid ventricular pacing at 250 beats per minute. Six of these dogs received NEP-I with candoxatril, 10 mg/kg PO BID, throughout evolving CHF. Responses to exogenous ANF, 10 micrograms/kg IV bolus, were assessed at baseline and after 6 days of CHF. Daily metabolic studies during evolving CHF with chronic NEP-I showed increased sodium excretion and renal cGMP generation consistent with enhanced renal activity of endogenous ANF compared with untreated controls. In addition, renal natriuretic and cGMP responses to exogenous ANF were intact in CHF with chronic NEP-I in contrast to markedly attenuated renal responses to exogenous ANF in untreated CHF. Despite enhanced ANF responsiveness and improved sodium balance in evolving CHF, a moderate degree of sodium retention was observed during chronic NEP-I in evolving CHF. Enzymatic degradation by neutral endopeptidase limits local renal responses to increases in endogenous and exogenous ANF in CHF independent of changes in systemic hemodynamics or augmented plasma concentrations of ANF. The moderate sodium retention observed during evolving CHF despite chronic NEP-I probably reflects the antinatriuretic effects of hemodynamic and humoral factors independent of ANF activity.

  20. Profiling of proteolytic enzymes in the gut of the tick Ixodes ricinus reveals an evolutionarily conserved network of aspartic and cysteine peptidases

    Directory of Open Access Journals (Sweden)

    Mareš Michael

    2008-03-01

    Full Text Available Abstract Background Ticks are vectors for a variety of viral, bacterial and parasitic diseases in human and domestic animals. To survive and reproduce ticks feed on host blood, yet our understanding of the intestinal proteolytic machinery used to derive absorbable nutrients from the blood meal is poor. Intestinal digestive processes are limiting factors for pathogen transmission since the tick gut presents the primary site of infection. Moreover, digestive enzymes may find practical application as anti-tick vaccine targets. Results Using the hard tick, Ixodes ricinus, we performed a functional activity scan of the peptidase complement in gut tissue extracts that demonstrated the presence of five types of peptidases of the cysteine and aspartic classes. We followed up with genetic screens of gut-derived cDNA to identify and clone genes encoding the cysteine peptidases cathepsins B, L and C, an asparaginyl endopeptidase (legumain, and the aspartic peptidase, cathepsin D. By RT-PCR, expression of asparaginyl endopeptidase and cathepsins B and D was restricted to gut tissue and to those developmental stages feeding on blood. Conclusion Overall, our results demonstrate the presence of a network of cysteine and aspartic peptidases that conceivably operates to digest host blood proteins in a concerted manner. Significantly, the peptidase components of this digestive network are orthologous to those described in other parasites, including nematodes and flatworms. Accordingly, the present data and those available for other tick species support the notion of an evolutionary conservation of a cysteine/aspartic peptidase system for digestion that includes ticks, but differs from that of insects relying on serine peptidases.

  1. An intermolecular binding mechanism involving multiple LysM domains mediates carbohydrate recognition by an endopeptidase

    DEFF Research Database (Denmark)

    Wong, Jaslyn E M M; Midtgaard, Søren Roi; Gysel, Kira

    2015-01-01

    LysM domains, which are frequently present as repetitive entities in both bacterial and plant proteins, are known to interact with carbohydrates containing N-acetylglucosamine (GlcNAc) moieties, such as chitin and peptidoglycan. In bacteria, the functional significance of the involvement of multi......LysM domains, which are frequently present as repetitive entities in both bacterial and plant proteins, are known to interact with carbohydrates containing N-acetylglucosamine (GlcNAc) moieties, such as chitin and peptidoglycan. In bacteria, the functional significance of the involvement...... of multiple LysM domains in substrate binding has so far lacked support from high-resolution structures of ligand-bound complexes. Here, a structural study of the Thermus thermophilus NlpC/P60 endopeptidase containing two LysM domains is presented. The crystal structure and small-angle X-ray scattering...... solution studies of this endopeptidase revealed the presence of a homodimer. The structure of the two LysM domains co-crystallized with N-acetyl-chitohexaose revealed a new intermolecular binding mode that may explain the differential interaction between LysM domains and short or long chitin oligomers...

  2. Major acid endopeptidases of the blood-feeding monogenean Eudiplozoon nipponicum (Heteronchoinea: Diplozoidae).

    Science.gov (United States)

    Jedličková, Lucie; Dvořáková, Hana; Kašný, Martin; Ilgová, Jana; Potěšil, David; Zdráhal, Zbyněk; Mikeš, Libor

    2016-04-01

    In parasitic flatworms, acid endopeptidases are involved in crucial processes, including digestion, invasion, interactions with the host immune system, etc. In haematophagous monogeneans, however, no solid information has been available about the occurrence of these enzymes. Here we aimed to identify major cysteine and aspartic endopeptidase activities in Eudiplozoon nipponicum, an invasive haematophagous parasite of common carp. Employing biochemical, proteomic and molecular tools, we found that cysteine peptidase activities prevailed in soluble protein extracts and excretory/secretory products (ESP) of E. nipponicum; the major part was cathepsin L-like in nature supplemented with cathepsin B-like activity. Significant activity of the aspartic cathepsin D also occurred in soluble protein extracts. The degradation of haemoglobin in the presence of ESP and worm protein extracts was completely inhibited by a combination of cysteine and aspartic peptidase inhibitors, and diminished by particular cathepsin L, B and D inhibitors. Mass spectrometry revealed several tryptic peptides in ESP matching to two translated sequences of cathepsin L genes, which were amplified from cDNA of E. nipponicum and bioinformatically annotated. The dominance of cysteine peptidases of cathepsin L type in E. nipponicum resembles the situation in, e.g. fasciolid trematodes.

  3. An intermolecular binding mechanism involving multiple LysM domains mediates carbohydrate recognition by an endopeptidase.

    Science.gov (United States)

    Wong, Jaslyn E M M; Midtgaard, Søren Roi; Gysel, Kira; Thygesen, Mikkel B; Sørensen, Kasper K; Jensen, Knud J; Stougaard, Jens; Thirup, Søren; Blaise, Mickaël

    2015-03-01

    LysM domains, which are frequently present as repetitive entities in both bacterial and plant proteins, are known to interact with carbohydrates containing N-acetylglucosamine (GlcNAc) moieties, such as chitin and peptidoglycan. In bacteria, the functional significance of the involvement of multiple LysM domains in substrate binding has so far lacked support from high-resolution structures of ligand-bound complexes. Here, a structural study of the Thermus thermophilus NlpC/P60 endopeptidase containing two LysM domains is presented. The crystal structure and small-angle X-ray scattering solution studies of this endopeptidase revealed the presence of a homodimer. The structure of the two LysM domains co-crystallized with N-acetyl-chitohexaose revealed a new intermolecular binding mode that may explain the differential interaction between LysM domains and short or long chitin oligomers. By combining the structural information with the three-dimensional model of peptidoglycan, a model suggesting how protein dimerization enhances the recognition of peptidoglycan is proposed.

  4. Alterations of prolyl endopeptidase activity in the plasma of children with autistic spectrum disorders

    Directory of Open Access Journals (Sweden)

    Avarseji Hassan

    2005-06-01

    Full Text Available Abstract Background Prolyl Endopeptidase (PEP, EC 3.4.21.26, a cytosolic endopeptidase, hydrolyses peptide bonds on the carboxyl side of proline residue in proteins with a relatively small molecular weight. It has been shown that altered PEP activity is associated with various psychological diseases such as schizophrenia, mania and depression. Autistic Spectrum Disorders (ASD are neuropsychiatric and behavioural syndromes affecting social behaviours and communication development. They are classified as developmental disorders. The aim of this study was to examine the hypothesis that PEP activity is also associated with ASDs. Methods Fluorometric assay was used to measure PEP activity in EDTA plasma in children with ASD (n = 18 aged 4–12 years (mean ± SD: 7.9 ± 2.5. These results were then compared to PEP activity in a control group of non-ASD children (n = 15 aged 2–10 years (mean ± SD: 6.4 ± 2.2. Results An alteration in PEP activity was found in the children with ASD compared to the control group. There was much greater variation of PEP activity in the group of ASD children when compared to the controls (SD= 39.9 and SD 9.6, respectively. This variation was significant (p Conclusion Our preliminary finding suggests a role for PEP enzyme in the pathophysiology of autism but further research should be conducted to establish its role in the aetiology of psychiatric and neurological disorders, including autism and related spectrum disorders.

  5. Cell sorting enriches Escherichia coli mutants that rely on peptidoglycan endopeptidases to suppress highly aberrant morphologies.

    Science.gov (United States)

    Laubacher, Mary E; Melquist, Amy L; Chandramohan, Lakshmi; Young, Kevin D

    2013-02-01

    Bacterial morphology imparts physiological advantages to cells in different environments and, judging by the fidelity with which shape is passed to daughter cells, is a tightly regulated characteristic. Surprisingly, only in the past 10 to 15 years has significant headway been made in identifying the mechanisms by which cells create and maintain particular shapes. One reason for this is that the relevant discoveries have relied heavily on the arduous, somewhat subjective process of manual microscopy. Here, we show that flow cytometry, coupled with the sorting capability of fluorescence-activated cell sorting (FACS), can detect, quantify, and enrich bacteria with morphological alterations. The light scattering properties of several highly aberrant morphological mutants of Escherichia coli were characterized by flow cytometry. Cells from a region that overlapped the distribution of normal rod-shaped cells were collected by FACS and reincubated. After 4 to 15 iterations of this enrichment process, suppressor mutants were isolated that returned almost all the population to a near-normal shape. Suppressors were successfully isolated from strains lacking three or four penicillin binding proteins (PBPs) but not from a mutant lacking a total of seven PBPs. The peptidoglycan endopeptidase, AmpH, was identified as being important for the suppression process, as was a related endopeptidase, MepA. The results validate the use of cell sorting as a means for studying bacterial morphology and identify at least one new class of enzymes required for the suppression of cell shape defects.

  6. Peptidase Activities of Tripeptidyl Peptidase Ⅰ(TPP Ⅰ): Exopeptidase and Endopeptidase

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The defect of TPP Ⅰ causes a disease, late infantile neuronal ceroid lipofuscinosis(LINCL, CLN2). To investigate the bio-activity of tripeptidyl peptidase Ⅰ(TPP Ⅰ) from rat kidneys, the effects of digestion of angiotensin Ⅱ(Ang Ⅱ) and a synthetic endo-type substrate(Gly1-Lys-Pro-Iie-Pro5-Phe-Phe-Arg-Leu-Lys10) via TPP Ⅰ were analyzed by HPLC and TOF-MS. The data suggest that the degradation rate of Ang Ⅱ can reach 18.2% by the rat TPP Ⅰ and DRV(Asp-Arg-Val) can be released from N-termini of Ang Ⅱ within 16 h. In addition, the synthetic endo-type substrate is cleaved at the same position between Phe6 and Phe7. Accordingly, TPP Ⅰ shows two kinds of peptidase activities. One is a tripeptidyl peptidase activity and the other is a pepstatin insensitive carboxyl endopeptidase activity. Tripeptidyl peptidase activity and pepstatin insensitive carboxyl endopeptidase activity seem to be dual phases of one enzyme, TPP Ⅰ.

  7. Purification of balansain I, an endopeptidase from unripe fruits of Bromelia balansae Mez (Bromeliaceae).

    Science.gov (United States)

    Pardo, M F; López, L M; Canals, F; Avilés, F X; Natalucci, C L; Caffini, N O

    2000-09-01

    A new plant endopeptidase was obtained from unripe fruits of Bromelia balansae Mez (Bromeliaceae). Crude extracts were partially purified by ethanol fractionation. This preparation (redissolved ethanol precipitate, REP) showed maximum activity at pH 8.8-9.2, was very stable even at high ionic strength values (no appreciable decrease in proteolytic activity could be detected after 24 h in 1 M sodium chloride solution at 37 degrees C), and exhibited high thermal stability (inactivation required heating for 60 min at 75 degrees C). Anion exchange chromatography allowed the isolation of a fraction purified to mass spectroscopy, SDS-PAGE, and IEF homogeneity, named balansain I, with pI = 5.45 and molecular mass = 23192 (mass spectrometry). The purification factor is low (2.9-fold), but the yield is high (48.3%), a common occurrence in plant organs with high proteolytic activity, where proteases represent the bulk of protein content of crude extracts. Balansain I exhibits a similar but narrower pH profile than that obtained for REP, with a maximum pH value approximately 9.0 and was inhibited by E-64 and other cysteine peptidases inhibitors but not affected by inhibitors of the other catalytic types of peptidases. The alanine and glutamine derivatives of N-alpha-carbobenzoxy-L-amino acid p-nitrophenyl esters was strongly preferred by the enzyme. The N-terminal sequence of balansain I showed a very high homology (85-90%) with other known Bromeliaceae endopeptidases.

  8. The Anti-Fibrotic Effect of Mycophenolic Acid–Induced Neutral Endopeptidase

    Science.gov (United States)

    Dell'Oglio, Maria Pia; Rossini, Michele; Divella, Chiara; Pontrelli, Paola; Verrienti, Raffaella; Rutigliano, Monica; Ditonno, Pasquale; Stifanelli, Patrizia; Ancona, Nicola; Schena, Francesco Paolo; Grandaliano, Giuseppe

    2010-01-01

    Mycophenolic acid (MPA) appears to have anti-fibrotic effects, but the molecular mechanisms underlying this are unknown. We prospectively studied 35 stable kidney transplant recipients maintained on cyclosporine and azathioprine. We converted 20 patients from azathioprine to enteric-coated mycophenolate sodium (EC-MPS) and continued the remaining 15 patients on azathioprine. Exploratory mRNA expression profiling, performed on five randomly selected EC-MPS patients, revealed significant upregulation of neutral endopeptidase (NEP), which is an enzyme that degrades angiotensin II. We confirmed these microarray data by measuring levels of NEP expression in all subjects; in addition, we found that NEP gene expression correlated inversely with proteinuria. In an additional 33 patients, glomerular and tubular NEP protein levels from renal graft biopsies were significantly higher among the 13 patients receiving cyclosporine + EC-MPS than among the 12 patients receiving cyclosporine + azathioprine or 8 patients receiving cyclosporine alone. Glomerular NEP expression inversely correlated with glomerulosclerosis and proteinuria, and tubular NEP expression inversely correlated with interstitial fibrosis. Incubation of human proximal tubular cells with MPA increased NEP gene expression in a dose- and time-dependent manner. Moreover, MPA reduced angiotensin II–induced expression of the profibrotic factor plasminogen activator inhibitor-1, and a specific NEP inhibitor completely reversed this effect. Taken together, our data suggest that MPA directly induces expression of neutral endopeptidase, which may reduce proteinuria and slow the progression of renal damage in kidney transplant recipients. PMID:20864690

  9. A cysteine endopeptidase ("dionain") is involved in the digestive fluid of Dionaea muscipula (Venus's fly-trap).

    Science.gov (United States)

    Takahashi, Kenji; Suzuki, Takehiro; Nishii, Wataru; Kubota, Keiko; Shibata, Chiaki; Isobe, Toshiaki; Dohmae, Naoshi

    2011-01-01

    The carnivorous plant Dionaea muscipula (Venus's flytrap) secretes proteinases into the digestive fluid to digest prey proteins. In this study, we obtained evidence that the digestive fluid contains a cysteine endopeptidase, presumably belonging to the papain family, through inhibitor studies and partial amino acid sequencing of the major SDS-PAGE band protein. The name "dionain" is proposed for the enzyme.

  10. Kinetics of Hydrolyzing Isolated Soy Protein by an Endopeptidase and its Conceptual Application in Process Engineering

    Directory of Open Access Journals (Sweden)

    Zebin Wang

    2012-04-01

    Full Text Available A response study and the effects of different parameters (pH, temperature and enzyme dose on kinetics of isolated soy protein hydrolysis by a trypsin-like endopeptidase (TL1 were conducted. Degree of hydrolysis (%DH data varied at different times under different hydrolysis conditions. Fitting the kinetics data to Michaelis-Menten kinetics model did not result in reasonable kinetic parameters, which implied that Michaelis-Menten kinetics was invalid for such a hydrolysis process. A kinetics model proposed by (Gonzalez-Tello, Camacho, Jurado, Paez, & Guadix, 1994 was found to fit the kinetics curve well and resulted in acceptable model parameters. A simple simulation example was performed to demonstrate the concept of how the kinetics equation could be applied in process engineering.

  11. AmpH, a bifunctional DD-endopeptidase and DD-carboxypeptidase of Escherichia coli.

    Science.gov (United States)

    González-Leiza, Silvia M; de Pedro, Miguel A; Ayala, Juan A

    2011-12-01

    In Escherichia coli, low-molecular-mass penicillin-binding proteins (LMM PBPs) are important for correct cell morphogenesis. These enzymes display DD-carboxypeptidase and/or dd-endopeptidase activities associated with maturation and remodeling of peptidoglycan (PG). AmpH has been classified as an AmpH-type class C LMM PBP, a group closely related to AmpC β-lactamases. AmpH has been associated with PG recycling, although its enzymatic activity remained uncharacterized until now. Construction and purification of His-tagged AmpH from E. coli permitted a detailed study of its enzymatic properties. The N-terminal export signal of AmpH is processed, but the protein remains membrane associated. The PBP nature of AmpH was demonstrated by its ability to bind the β-lactams Bocillin FL (a fluorescent penicillin) and cefmetazole. In vitro assays with AmpH and specific muropeptides demonstrated that AmpH is a bifunctional DD-endopeptidase and DD-carboxypeptidase. Indeed, the enzyme cleaved the cross-linked dimers tetrapentapeptide (D45) and tetratetrapeptide (D44) with efficiencies (k(cat)/K(m)) of 1,200 M(-1) s(-1) and 670 M(-1) s(-1), respectively, and removed the terminal D-alanine from muropeptides with a C-terminal D-Ala-D-Ala dipeptide. Both DD-peptidase activities were inhibited by 40 μM cefmetazole. AmpH also displayed a weak β-lactamase activity for nitrocefin of 1.4 × 10(-3) nmol/μg protein/min, 1/1,000 the rate obtained for AmpC under the same conditions. AmpH was also active on purified sacculi, exhibiting the bifunctional character that was seen with pure muropeptides. The wide substrate spectrum of the DD-peptidase activities associated with AmpH supports a role for this protein in PG remodeling or recycling.

  12. Structural basis for type VI secreted peptidoglycan dl-endopeptidase function, specificity and neutralization in Serratia marcescens

    Energy Technology Data Exchange (ETDEWEB)

    Srikannathasan, Velupillai; English, Grant [University of Dundee, Dundee DD1 5EH, Scotland (United Kingdom); Bui, Nhat Khai [Newcastle University, Newcastle upon Tyne NE2 4HH (United Kingdom); Trunk, Katharina; O’Rourke, Patrick E. F.; Rao, Vincenzo A. [University of Dundee, Dundee DD1 5EH, Scotland (United Kingdom); Vollmer, Waldemar [Newcastle University, Newcastle upon Tyne NE2 4HH (United Kingdom); Coulthurst, Sarah J., E-mail: s.j.coulthurst@dundee.ac.uk; Hunter, William N., E-mail: s.j.coulthurst@dundee.ac.uk [University of Dundee, Dundee DD1 5EH, Scotland (United Kingdom)

    2013-12-01

    Crystal structures of type VI secretion system-associated immunity proteins, a peptidoglycan endopeptidase and a complex of the endopeptidase and its cognate immunity protein are reported together with assays of endopeptidase activity and functional assessment. Some Gram-negative bacteria target their competitors by exploiting the type VI secretion system to extrude toxic effector proteins. To prevent self-harm, these bacteria also produce highly specific immunity proteins that neutralize these antagonistic effectors. Here, the peptidoglycan endopeptidase specificity of two type VI secretion-system-associated effectors from Serratia marcescens is characterized. These small secreted proteins, Ssp1 and Ssp2, cleave between γ-d-glutamic acid and l-meso-diaminopimelic acid with different specificities. Ssp2 degrades the acceptor part of cross-linked tetratetrapeptides. Ssp1 displays greater promiscuity and cleaves monomeric tripeptides, tetrapeptides and pentapeptides and dimeric tetratetra and tetrapenta muropeptides on both the acceptor and donor strands. Functional assays confirm the identity of a catalytic cysteine in these endopeptidases and crystal structures provide information on the structure–activity relationships of Ssp1 and, by comparison, of related effectors. Functional assays also reveal that neutralization of these effectors by their cognate immunity proteins, which are called resistance-associated proteins (Raps), contributes an essential role to cell fitness. The structures of two immunity proteins, Rap1a and Rap2a, responsible for the neutralization of Ssp1 and Ssp2-like endopeptidases, respectively, revealed two distinct folds, with that of Rap1a not having previously been observed. The structure of the Ssp1–Rap1a complex revealed a tightly bound heteromeric assembly with two effector molecules flanking a Rap1a dimer. A highly effective steric block of the Ssp1 active site forms the basis of effector neutralization. Comparisons with Ssp2–Rap2

  13. Purification and characterization of four new cysteine endopeptidases from fruits of Bromelia pinguin L. grown in Cuba.

    Science.gov (United States)

    Payrol, Juan Abreu; Obregón, Walter D; Trejo, Sebastián A; Caffini, Néstor O

    2008-02-01

    Bromelia pinguin L. is a plant broadly distributed in Central America and Caribbean islands. The fruits have been used in traditional medicine as anthelmintic, probably owed to the presence of a mixture of cysteine endopeptidases, initially termed pinguinain. This work deals with the purification and characterization of the four main components of that mixture, two of them showing acid pI and the other two alkaline pI. Molecular masses (SDS-PAGE and MALDI-TOF), N-terminal sequence and the reactivity and kinetic parameters versus synthetic substrates (p-nitrophenyl-N-alpha-CBZ-amino acid esters, PFLNA, Z-Arg-Arg-p-NA, and Z-Phe-Arg-p-NA) of the studied peptidases are given, as well as the N-terminal sequences of the enzymes and the homology degree with other plant endopeptidases.

  14. Enzymatic and Structural Characterization of the Major Endopeptidase in the Venus Flytrap Digestion Fluid.

    Science.gov (United States)

    Risør, Michael W; Thomsen, Line R; Sanggaard, Kristian W; Nielsen, Tania A; Thøgersen, Ida B; Lukassen, Marie V; Rossen, Litten; Garcia-Ferrer, Irene; Guevara, Tibisay; Scavenius, Carsten; Meinjohanns, Ernst; Gomis-Rüth, F Xavier; Enghild, Jan J

    2016-01-29

    Carnivorous plants primarily use aspartic proteases during digestion of captured prey. In contrast, the major endopeptidases in the digestive fluid of the Venus flytrap (Dionaea muscipula) are cysteine proteases (dionain-1 to -4). Here, we present the crystal structure of mature dionain-1 in covalent complex with inhibitor E-64 at 1.5 Å resolution. The enzyme exhibits an overall protein fold reminiscent of other plant cysteine proteases. The inactive glycosylated pro-form undergoes autoprocessing and self-activation, optimally at the physiologically relevant pH value of 3.6, at which the protective effect of the pro-domain is lost. The mature enzyme was able to efficiently degrade a Drosophila fly protein extract at pH 4 showing high activity against the abundant Lys- and Arg-rich protein, myosin. The substrate specificity of dionain-1 was largely similar to that of papain with a preference for hydrophobic and aliphatic residues in subsite S2 and for positively charged residues in S1. A tentative structure of the pro-domain was obtained by homology modeling and suggested that a pro-peptide Lys residue intrudes into the S2 pocket, which is more spacious than in papain. This study provides the first analysis of a cysteine protease from the digestive fluid of a carnivorous plant and confirms the close relationship between carnivorous action and plant defense mechanisms. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Enzymatic and Structural Characterization of the Major Endopeptidase in the Venus Flytrap Digestion Fluid*

    Science.gov (United States)

    Risør, Michael W.; Thomsen, Line R.; Sanggaard, Kristian W.; Nielsen, Tania A.; Thøgersen, Ida B.; Lukassen, Marie V.; Rossen, Litten; Garcia-Ferrer, Irene; Guevara, Tibisay; Scavenius, Carsten; Meinjohanns, Ernst; Gomis-Rüth, F. Xavier; Enghild, Jan J.

    2016-01-01

    Carnivorous plants primarily use aspartic proteases during digestion of captured prey. In contrast, the major endopeptidases in the digestive fluid of the Venus flytrap (Dionaea muscipula) are cysteine proteases (dionain-1 to -4). Here, we present the crystal structure of mature dionain-1 in covalent complex with inhibitor E-64 at 1.5 Å resolution. The enzyme exhibits an overall protein fold reminiscent of other plant cysteine proteases. The inactive glycosylated pro-form undergoes autoprocessing and self-activation, optimally at the physiologically relevant pH value of 3.6, at which the protective effect of the pro-domain is lost. The mature enzyme was able to efficiently degrade a Drosophila fly protein extract at pH 4 showing high activity against the abundant Lys- and Arg-rich protein, myosin. The substrate specificity of dionain-1 was largely similar to that of papain with a preference for hydrophobic and aliphatic residues in subsite S2 and for positively charged residues in S1. A tentative structure of the pro-domain was obtained by homology modeling and suggested that a pro-peptide Lys residue intrudes into the S2 pocket, which is more spacious than in papain. This study provides the first analysis of a cysteine protease from the digestive fluid of a carnivorous plant and confirms the close relationship between carnivorous action and plant defense mechanisms. PMID:26627834

  16. Funastrain c II: a cysteine endopeptidase purified from the latex of Funastrum clausum.

    Science.gov (United States)

    Morcelle, Susana R; Trejo, Sebastián A; Canals, Francesc; Avilés, Francesc X; Priolo, Nora S

    2004-04-01

    A cysteine endopeptidase, named funastrain c II, was isolated and characterized from the latex of Funastrum clausum (Asclepiadaceae). The molecular mass (mass spectrometry) of the protease was 23.636 kDa. The analysis of funastrain c II by SDS-PAGE revealed a single polypeptide chain. The enzyme showed a remarkable stability of its caseinolytic activity after incubation at temperatures as high as 70 degrees C. Inhibition and activation assays indicated the cysteinic nature of the funastrain c II catalytic site. The optimum pH of funastrain c II enzymatic activity varied according to the substrate used (9.0-10.0 for casein and 6.2-6.8 for PFLNA). Kinetic parameters were determined for N-alpha-CBZ-Ala p-nitrophenyl ester (Km = 0.0243 mM, kcat = 1.5 s(-1)) and L-pyroglutamyl-L-phenylalanyl-L-leucine-p-nitroanilide (PFLNA; KM = 0.1011 mM, kcat = 0.9 s(-1)). The N-terminal sequence of funastrain c II showed considerable similarity to other proteases isolated from latex of different Asclepiadaceae species as well as to other cysteine proteinases belonging to the papain family.

  17. PepO, a CovRS-controlled endopeptidase, disrupts Streptococcus pyogenes quorum sensing.

    Science.gov (United States)

    Wilkening, Reid V; Chang, Jennifer C; Federle, Michael J

    2016-01-01

    Group A Streptococcus (GAS, Streptococcus pyogenes) is a human-restricted pathogen with a capacity to both colonize asymptomatically and cause illnesses ranging from pharyngitis to necrotizing fasciitis. An understanding of how and when GAS switches between genetic programs governing these different lifestyles has remained an enduring mystery and likely requires carefully tuned environmental sensors to activate and silence genetic schemes when appropriate. Herein, we describe the relationship between the Control of Virulence (CovRS, CsrRS) two-component system and the Rgg2/3 quorum-sensing pathway. We demonstrate that responses of CovRS to the stress signals Mg(2+) and a fragment of the antimicrobial peptide LL-37 result in modulated activity of pheromone signaling of the Rgg2/3 pathway through a means of proteolysis of SHP peptide pheromones. This degradation is mediated by the cytoplasmic endopeptidase PepO, which is the first identified enzymatic silencer of an RRNPP-type quorum-sensing pathway. These results suggest that under conditions in which the virulence potential of GAS is elevated (i.e. enhanced virulence gene expression), cellular responses mediated by the Rgg2/3 pathway are abrogated and allow individuals to escape from group behavior. These results also indicate that Rgg2/3 signaling is instead functional during non-virulent GAS lifestyles.

  18. Internally quenched fluorescent peptide libraries with randomized sequences designed to detect endopeptidases.

    Science.gov (United States)

    Oliveira, Lilian C G; Silva, Vinícius O; Okamoto, Debora N; Kondo, Marcia Y; Santos, Saara M B; Hirata, Isaura Y; Vallim, Marcelo A; Pascon, Renata C; Gouvea, Iuri E; Juliano, Maria A; Juliano, Luiz

    2012-02-01

    Identification of synthetic peptide substrates for novel peptidases is an essential step for their study. With this purpose we synthesized fluorescence resonance energy transfer (FRET) peptide libraries Abz (or MCA)-GXXXXXQ-EDDnp and Abz (or MCA)-GXXZXXQ-EDDnp, where X consists of an equimolar mixture of all amino acids, the Z position is fixed with one of the proteinogenic amino acids (cysteine was excluded), Abz (ortho-aminobenzoic acid) or MCA ([7-amino-4-methyl]coumarin) is the fluorescence donor and Q-EDDnp (glutamine-[N-(2,4-dinitrophenyl)-ethylenediamine]) is the fluorescence acceptor. The peptide libraries MCA-GXXX↓XXQ-EDDnp and MCA-GXXZ↓XXQ-EDDnp were cleaved as indicated (↓) by trypsin, chymotrypsin, cathepsin L, pepsin A, and Eqolisin as confirmed by Edman degradation of the products derived from the digestion of these libraries. The best hydrolyzed Abz-GXXZXXQ-EDDnp sublibraries by these proteases, including Dengue 2 virus NS2B-NS3 protease, contained amino acids at the Z position that are reported to be well accepted by their S(1) subsite. The pH profiles of the hydrolytic activities of these canonical proteases on the libraries were similar to those reported for typical substrates. The FRET peptide libraries provide an efficient and simple approach for detecting nanomolar concentrations of endopeptidases and are useful for initial specificity characterization as performed for two proteases secreted by a Bacillus subtilis.

  19. The Roles of Streptozotocin Neurotoxicity and Neutral Endopeptidase in Murine Experimental Diabetic Neuropathy

    Directory of Open Access Journals (Sweden)

    Eric Davidson

    2009-01-01

    Full Text Available We demonstrated that inhibition of neutral endopeptidase (NEP, a protease that degrades vaso- and neuroactive peptides, improves vascular and neural function in diabetic animal models. In this study we explored the role of NEP in neuropathy related to either insulin-deficient diabetes or diet-induced obesity using NEP deficient (−/− mice. Initial studies showed that streptozotocin, in the absence of subsequent hyperglycemia, did not induce nerve conduction slowing or paw thermal hypoalgesia. Glucose disposal was impaired in both C57Bl/6 and NEP −/− mice fed a high fat diet. Thermal hypoalgesia and nerve conduction slowing were present in both streptozotocin-diabetic and high fat fed C57Bl/6 mice but not in NEP −/− mice exposed to either streptozotocin-induced diabetes or a high fat diet. These studies suggest that streptozotocin does not induce neurotoxicity in mice and that NEP plays a role in regulating nerve function in insulin-deficient diabetes and diet-induced obesity.

  20. The Roles of Streptozotocin Neurotoxicity and Neutral Endopeptidase in Murine Experimental Diabetic Neuropathy

    Science.gov (United States)

    Davidson, Eric; Coppey, Lawrence; Lu, Bao; Arballo, Victor; Calcutt, Nigel A.; Gerard, Craig; Yorek, Mark

    2009-01-01

    We demonstrated that inhibition of neutral endopeptidase (NEP), a protease that degrades vaso- and neuroactive peptides, improves vascular and neural function in diabetic animal models. In this study we explored the role of NEP in neuropathy related to either insulin-deficient diabetes or diet-induced obesity using NEP deficient (−/−) mice. Initial studies showed that streptozotocin, in the absence of subsequent hyperglycemia, did not induce nerve conduction slowing or paw thermal hypoalgesia. Glucose disposal was impaired in both C57Bl/6 and NEP −/− mice fed a high fat diet. Thermal hypoalgesia and nerve conduction slowing were present in both streptozotocin-diabetic and high fat fed C57Bl/6 mice but not in NEP −/− mice exposed to either streptozotocin-induced diabetes or a high fat diet. These studies suggest that streptozotocin does not induce neurotoxicity in mice and that NEP plays a role in regulating nerve function in insulin-deficient diabetes and diet-induced obesity. PMID:20148083

  1. Toll-Like Receptor 4 Engagement Mediates Prolyl Endopeptidase Release from Airway Epithelia via Exosomes.

    Science.gov (United States)

    Szul, Tomasz; Bratcher, Preston E; Fraser, Kyle B; Kong, Michele; Tirouvanziam, Rabindra; Ingersoll, Sarah; Sztul, Elizabeth; Rangarajan, Sunil; Blalock, J Edwin; Xu, Xin; Gaggar, Amit

    2016-03-01

    Proteases are important regulators of pulmonary remodeling and airway inflammation. Recently, we have characterized the enzyme prolyl endopeptidase (PE), a serine peptidase, as a critical protease in the generation of the neutrophil chemoattractant tripeptide Pro-Gly-Pro (PGP) from collagen. However, PE has been characterized as a cytosolic enzyme, and the mechanism mediating PE release extracellularly remains unknown. We examined the role of exosomes derived from airway epithelia as a mechanism for PE release and the potential extracellular signals that regulate the release of these exosomes. We demonstrate a specific regulatory pathway of exosome release from airway epithelia and identify PE as novel exosome cargo. LPS stimulation of airway epithelial cells induces release of PE-containing exosomes, which is significantly attenuated by small interfering RNA depletion of Toll-like receptor 4 (TLR4). These differences were recapitulated upon intratracheal LPS administration in mice competent versus deficient for TLR4 signaling. Finally, sputum samples from subjects with cystic fibrosis colonized with Pseudomonas aeruginosa demonstrate elevated exosome content and increased PE levels. This TLR4-based mechanism highlights the first report of nonstochastic release of exosomes in the lung and couples TLR4 activation with matrikine generation. The increased quantity of these proteolytic exosomes in the airways of subjects with chronic lung disease highlights a new mechanism of injury and inflammation in the pathogenesis of pulmonary disorders.

  2. Cooperative binding of LysM domains determines the carbohydrate affinity of a bacterial endopeptidase protein.

    Science.gov (United States)

    Wong, Jaslyn E M M; Alsarraf, Husam M A B; Kaspersen, Jørn Døvling; Pedersen, Jan Skov; Stougaard, Jens; Thirup, Søren; Blaise, Mickaël

    2014-02-01

    Cellulose, chitin and peptidoglycan are major long-chain carbohydrates in living organisms, and constitute a substantial fraction of the biomass. Characterization of the biochemical basis of dynamic changes and degradation of these β,1-4-linked carbohydrates is therefore important for both functional studies of biological polymers and biotechnology. Here, we investigated the functional role of multiplicity of the carbohydrate-binding lysin motif (LysM) domain that is found in proteins involved in bacterial peptidoglycan synthesis and remodelling. The Bacillus subtilis peptidoglycan-hydrolysing NlpC/P60 D,L-endopeptidase, cell wall-lytic enzyme associated with cell separation, possesses four LysM domains. The contribution of each LysM domain was determined by direct carbohydrate-binding studies in aqueous solution with microscale thermophoresis. We found that bacterial LysM domains have affinity for N-acetylglucosamine (GlcNac) polymers in the lower-micromolar range. Moreover, we demonstrated that a single LysM domain is able to bind carbohydrate ligands, and that LysM domains act additively to increase the binding affinity. Our study reveals that affinity for GlcNAc polymers correlates with the chain length of the carbohydrate, and suggests that binding of long carbohydrates is mediated by LysM domain cooperativity. We also show that bacterial LysM domains, in contrast to plant LysM domains, do not discriminate between GlcNAc polymers, and recognize both peptidoglycan fragments and chitin polymers with similar affinity. Finally, an Ala replacement study suggested that the carbohydrate-binding site in LysM-containing proteins is conserved across phyla. © 2013 FEBS.

  3. A neuroprotective brain-penetrating endopeptidase fusion protein ameliorates Alzheimer disease pathology and restores neurogenesis.

    Science.gov (United States)

    Spencer, Brian; Verma, Inder; Desplats, Paula; Morvinski, Dinorah; Rockenstein, Ed; Adame, Anthony; Masliah, Eliezer

    2014-06-20

    Alzheimer disease (AD) is characterized by widespread neurodegeneration throughout the association cortex and limbic system, deposition of amyloid-β peptide (Aβ) in the neuropil and around the blood vessels, and formation of neurofibrillary tangles. The endopeptidase neprilysin has been successfully used to reduce the accumulation of Aβ following intracranial viral vector delivery or ex vivo manipulated intracranial delivery. These therapies have relied on direct injections into the brain, whereas a clinically desirable therapy would involve i.v. infusion of a recombinant enzyme. We previously characterized a recombinant neprilysin that contained a 38-amino acid brain-targeting domain. Recombinant cell lines have been generated expressing this brain-targeted enzyme (ASN12). In this report, we characterize the ASN12 recombinant protein for pharmacology in a mouse as well as efficacy in two APPtg mouse models of AD. The recombinant ASN12 transited to the brain with a t½ of 24 h and accumulated to 1.7% of injected dose at 24 h following i.v. delivery. We examined pharmacodynamics in the tg2576 APPtg mouse with the prion promoter APP695 SWE mutation and in the Line41 mThy1 APP751 mutation mouse. Treatment of either APPtg mouse resulted in reduced Aβ, increased neuronal synapses, and improved learning and memory. In addition, the Line41 APPtg mice showed increased levels of C-terminal neuropeptide Y fragments and increased neurogenesis. These results suggest that the recombinant brain-targeted neprilysin, ASN12, may be an effective treatment for AD and warrant further investigation in clinical trials.

  4. Renal Actions of Neutral Endopeptidase Inhibition in Rats with Chronic Heart Failure

    Directory of Open Access Journals (Sweden)

    Amr M. Abbas

    2010-01-01

    Full Text Available Problem statement: We aim to evaluate the effects of acute and chronic inhibition of Neutral EndoPeptidase (NEP, by ONO-9902, on plasma and renal NEP gene expression, hemodynamic and renal parameters in rats with Chronic Heart Failure (CHF following left Coronary Artery Ligation (CAL. Approach: Forty eight male Sprague-Dawley rats (220-240 g were divided into sham and CAL groups. Myocardial infarction was induced by left CAL. All rats were further subdivided into untreated and orally treated with ONO-9902 (300 mg kg-1 day-1 from the 1st to 6th weeks after the operation. At the 1st and 6th weeks after the operation, gene expression of plasma and renal NEP, plasma ANP, cGMP and aldosterone concentrations, urine volume, Na and ANP excretion, creatinine clearance and renal cGMP generation were measured. Results: CAL leads to sodium and water retention, increased renal NEP gene expression, plasma ANP and aldosterone and decreased renal cGMP generation and plasma NEP gene expression. Acute treatment of CAL rats by ONO-9902, at the 1st week after the operation, inhibited plasma and renal NEP gene expression with increased plasma ANP, which caused diuresis, natriuresis and increased renal cGMP generation. Moreover, chronic treatment of those rats by ONO-9902 decreased plasma and renal NEP gene expression, plasma aldosterone, increased plasma ANP but non significantly, and caused diuresis, natriuresis with increased renal cGMP generation. GFR was not significantly changed before or after treatment. Conclusion: Chronic treatment with NEP inhibitor decreases Na and water retention in rats with CHF by enhancing ANP action and suppressing aldosterone secretion. So, ONO-9902 may offer a new therapeutic approach in patients with CHF.

  5. In silico methods to identify meat-derived prolyl endopeptidase inhibitors.

    Science.gov (United States)

    Lafarga, Tomas; O'Connor, Paula; Hayes, Maria

    2015-05-15

    According to the World Health Organization (WHO), approximately 450 million people suffer from mental or neurological disorders and five of the ten leading causes of disability and premature death worldwide are psychiatric conditions. Social, biological and neurological sciences provided extensive understanding into the role of risk and protective factors in the development of mental disorders and poor mental health. Altered activity of a number of enzymes, such as prolyl endopeptidase (PEP, EC 3.4.21.26), has been linked to the prevention and treatment of a number of mental disorders, including anxiety, depression and Alzheimer's disease. The inhibition of PEP has potential for use in the prevention and in the treatment of mental disorders. The objective of this work was to identify PEP-inhibitory peptides from meat proteins using in silico methods. In this paper, five proteins commonly found in meat by-products were evaluated as a substrate for use in the generation of PEP inhibitory peptides. These include serum albumin, collagen and myosin. These proteins were cleaved in silico using BIOPEP and ExPASy PeptideCutter and the generated peptides were compared to known PEP-inhibiting peptides in the database of BIOPEP. A number of novel PEP inhibitory peptide sequences were identified in this study, including PPL, APPH, IPP and PPG with corresponding IC50 values of 2.86, 3.95, 4.02 and 2.70 mM, respectively. This work demonstrates the usefulness of in silico analysis for predicting the release of PEP-inhibiting peptides from meat proteins.

  6. Identification of glutamic acid 646 as a zinc-coordinating residue in endopeptidase-24.11.

    Science.gov (United States)

    Le Moual, H; Devault, A; Roques, B P; Crine, P; Boileau, G

    1991-08-25

    Neutral endopeptidase (EC 3.424.11, NEP) is a membrane-bound zinc-metallopeptidase. The substrate specificity and catalytic activity of NEP resemble those of thermolysin, a bacterial zinc-metalloprotease. Comparison of the primary structure of both enzymes suggests that several amino acids present in the active site of thermolysin are also found in NEP. Using site-directed mutagenesis of the cDNA encoding the NEP sequence, we have already shown that His residues 583 and 587 are two of the three zinc ligands. In order to identify the third zinc ligand, we have substituted Val or Asp for Glu616 or Glu646. Val616 NEP showed the same kinetic parameters as the non-mutated NEP. In contrast, the mutant Val646 NEP was almost completely devoid of catalytic activity and unable to bind the tritiated inhibitor [3H]N-[2(R,S)-3-hydroxyaminocarbonyl-2-benzyl-1-oxypropyl]gl ycine, the binding of which is dependent on the presence of the zinc ion. Replacing Glu for Asp at position 646 conserved the negative charge, and the mutant enzyme exhibited the same Km value as the non-mutated enzyme, but kCat was decreased to less than 3% of the value of the non-mutated enzyme. When compared to the non-mutated enzyme Asp646 NEP showed a higher susceptibility to chelating agents, but bound the tritiated inhibitor with the same affinity. Taken together, these observations strongly suggest that Glu646 of NEP is the third zinc-coordinating residue and is equivalent to Glu166 in thermolysin.

  7. Rapid degradation of D- and L-succinimide-containing peptides by a post-proline endopeptidase from human erythrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Momand, J.; Clarke, S.

    1987-12-01

    The authors have been interested in the metabolic fate of proteins containing aspartyl succinimide (Asu) residues. These residues can be derived from the spontaneous rearrangement of Asp and Asn residues and from the spontaneous demethylation of enzymatically methylated L-isoAsp and D-Asp residues. Incubation of the synthetic hexapeptide N-Ac-Val-Tyr-Pro-Asu-Gly-Ala with the cytosolic fraction of human erythrocytes resulted in rapid cleavage of the prolyl-aspartyl succinimide bond producing the tripeptide N-Ac-Val-Try-Pro. The rate of this reaction is equal for both L- and D-Asu-containing peptides and is 10-fold greater that the rate of cleavage of a corresponding peptide containing a normal Pro-Asp linkage. When the aspartyl succinimide ring was replaced with an isoaspartyl residue, the cleavage rate was about 5 times that of the normal Pro-Asp peptide. The tripeptide-producing activity copurified on DEAE-cellulose chromatography with an activity that cleaves N-carbobenzoxy-Gly-Pro-4-methylcoumarin-7-amide, a post-proline endopeptidase substrate. These two activities were both inhibited by an antiserum to rat brain post-proline endopeptidase, and it appears that they are catalyzed by the same enzyme. This enzyme has a molecular weight of approximately 80,000 and is covalently labeled and inhibited by (/sup 3/H) diisopropyl fluorophosphate. The facile cleavage of the succinimide- and isoaspartyl-containing peptides by this post-proline endopeptidase suggests that it may play a role in the metabolism of peptides containing altered aspartyl residues.

  8. Structural basis for type VI secreted peptidoglycan DL-endopeptidase function, specificity and neutralization in Serratia marcescens.

    Science.gov (United States)

    Srikannathasan, Velupillai; English, Grant; Bui, Nhat Khai; Trunk, Katharina; O'Rourke, Patrick E F; Rao, Vincenzo A; Vollmer, Waldemar; Coulthurst, Sarah J; Hunter, William N

    2013-12-01

    Some Gram-negative bacteria target their competitors by exploiting the type VI secretion system to extrude toxic effector proteins. To prevent self-harm, these bacteria also produce highly specific immunity proteins that neutralize these antagonistic effectors. Here, the peptidoglycan endopeptidase specificity of two type VI secretion-system-associated effectors from Serratia marcescens is characterized. These small secreted proteins, Ssp1 and Ssp2, cleave between γ-D-glutamic acid and L-meso-diaminopimelic acid with different specificities. Ssp2 degrades the acceptor part of cross-linked tetratetrapeptides. Ssp1 displays greater promiscuity and cleaves monomeric tripeptides, tetrapeptides and pentapeptides and dimeric tetratetra and tetrapenta muropeptides on both the acceptor and donor strands. Functional assays confirm the identity of a catalytic cysteine in these endopeptidases and crystal structures provide information on the structure-activity relationships of Ssp1 and, by comparison, of related effectors. Functional assays also reveal that neutralization of these effectors by their cognate immunity proteins, which are called resistance-associated proteins (Raps), contributes an essential role to cell fitness. The structures of two immunity proteins, Rap1a and Rap2a, responsible for the neutralization of Ssp1 and Ssp2-like endopeptidases, respectively, revealed two distinct folds, with that of Rap1a not having previously been observed. The structure of the Ssp1-Rap1a complex revealed a tightly bound heteromeric assembly with two effector molecules flanking a Rap1a dimer. A highly effective steric block of the Ssp1 active site forms the basis of effector neutralization. Comparisons with Ssp2-Rap2a orthologues suggest that the specificity of these immunity proteins for neutralizing effectors is fold-dependent and that in cases where the fold is conserved sequence differences contribute to the specificity of effector-immunity protein interactions.

  9. Identification of the type 2 proinsulin processing endopeptidase as PC2, a member of the eukaryote subtilisin family.

    Science.gov (United States)

    Bennett, D L; Bailyes, E M; Nielsen, E; Guest, P C; Rutherford, N G; Arden, S D; Hutton, J C

    1992-07-25

    Enzymological studies have implicated two Ca(2+)-dependent endopeptidases in the conversion of proinsulin to insulin; a type 1 activity which cleaves on the C-terminal side of Arg31-Arg32 and a type 2 activity which cleaves C-terminally to Lys64-Arg65 in the proinsulin sequence. The possibility that these enzymes are related to the recently discovered family of mammalian subtilisin-like gene products (furin, PC2, and PC3) and the yeast propheromone-converting enzyme (KEX-2), was investigated. Degenerate oligonucleotide primers flanking the putative catalytic domain within this gene family were used in a polymerase chain reaction to amplify related sequences from rat insulinoma cDNA. One major product of 700 base pairs was obtained which was greater than 99% identical to the corresponding rat PC2 sequence. This cDNA was subcloned into the bacterial expression vector pGEX-3X to generate a recombinant protein for antibody production. Western blot analysis showed the immunoreactivity was prominent in neuroendocrine tissues as a 65-kDa protein. It was concentrated in secretory granule-enriched fractions of insulinoma tissue, where it was present as a readily solubilized monomeric protein. Deglycosylation studies using endoglycosidase H and N-glycanase showed that the 65-kDa protein was comprised of approximately 9% carbohydrate, consistent with the presence of three consensus sequences for N-linked glycosylation in rat PC2. The immunoreactivity co-eluted with the type 2 proinsulin endopeptidase on gel filtration and ion-exchange chromatography and the antisera specifically immunoprecipitated type 2 activity from insulin granule extracts. N-terminal sequence analysis of the immunoreactive protein gave two sequences which corresponded to residues 109-112 and 112-119 of rat PC2. This indicated that posttranslational processing of PC2 itself occurs C-terminally to basic amino acids to produce the mature enzyme. It is concluded that PC2 is the type 2 endopeptidase involved

  10. Vacuolar processing enzyme in plant programmed cell death

    Directory of Open Access Journals (Sweden)

    Noriyuki eHatsugai

    2015-04-01

    Full Text Available Vacuolar processing enzyme (VPE is a cysteine proteinase originally identified as the proteinase responsible for the maturation and activation of vacuolar proteins in plants, and it is known to be an orthologue of animal asparaginyl endopeptidase (AEP/VPE/legumain. VPE has been shown to exhibit enzymatic properties similar to that of caspase 1, which is a cysteine protease that mediates the programmed cell death (PCD pathway in animals. Although there is limited sequence identity between VPE and caspase 1, their predicted three-dimensional structures revealed that the essential amino-acid residues for these enzymes form similar pockets for the substrate peptide YVAD. In contrast to the cytosolic localization of caspases, VPE is localized in vacuoles. VPE provokes vacuolar rupture, initiating the proteolytic cascade leading to PCD in the plant immune response. It has become apparent that the VPE-dependent PCD pathway is involved not only in the immune response, but also in the responses to a variety of stress inducers and in the development of various tissues. This review summarizes the current knowledge on the contribution of VPE to plant PCD and its role in vacuole-mediated cell death, and it also compares VPE with the animal cell death executor caspase 1.

  11. Cloning and expression of a novel prolyl endopeptidase from Aspergillus oryzae and its application in beer stabilization.

    Science.gov (United States)

    Kang, Chao; Yu, Xiao-Wei; Xu, Yan

    2015-02-01

    A novel prolyl endopeptidase gene from Aspergillus oryzae was cloned and expressed in Pichia pastoris. Amino acid sequence analysis of the prolyl endopeptidase from Aspergillus oryzae (AO-PEP) showed that this enzyme belongs to a class serine peptide S28 family. Expression, purification and characterization of AO-PEP were analyzed. The optimum pH and temperature were pH 5.0 and 40 °C, respectively. The enzyme was activated and stabilized by metal ion Ca(2+) and inhibited by Zn(2+), Mn(2+), Al(3+), and Cu(2+). The K m and k cat values of the purified enzyme for different substrates were evaluated. The results implied that the recombinant AO-PEP possessed higher affinity for the larger substrate. A fed-batch strategy was developed for the high-cell-density fermentation and the enzyme activity reached 1,130 U/l after cultivation in 7 l fermentor. After addition of AO-PEP during the fermentation phase of beer brewing, demonstrated the potential application of AO-PEP in the non-biological stability of beer, which favor further industrial development of this new enzyme in beer stabilization, due to its reducing operational costs, as well as no beer losses unlike regeneration process and beer lost with regenerated polyvinylpolypyrrolidone system.

  12. Discovery, cloning and characterisation of proline specific prolyl endopeptidase, a gluten degrading thermo-stable enzyme from Sphaerobacter thermophiles

    DEFF Research Database (Denmark)

    Shetty, Radhakrishna; Vestergaard, Mike; Jessen, Flemming

    2017-01-01

    Gluten free products have emerged during the last decades, as a result of a growing public concern and technological advancements allowing gluten reduction in food products. One approach is to use gluten degrading enzymes, typically at low or ambient temperatures, whereas many food production...... processes occur at elevated temperature. We present in this paper, the discovery, cloning and characterisation of a novel recombinant thermostable gluten degrading enzyme, a proline specific prolyl endoprotease (PEP) from Sphaerobacter thermophiles. The molecular mass of the prolyl endopeptidase...... at 63 °C was higher than 75 %. The enzyme was activated and stabilized by Co2+ and inhibited by Mg2+, K+ and Ca2+ followed by Zn2+, Na+, Mn2+, Al3+, and Cu2+. The Km and kcat values of the purified enzyme for different substrates were evaluated. The ability to degrade immunogenic gluten peptides...

  13. Substrate phosphorylation affects degradation and interaction to endopeptidase 24.15, neurolysin, and angiotensin-converting enzyme.

    Science.gov (United States)

    Machado, M F M; Cunha, F M; Berti, D A; Heimann, A S; Klitzke, C F; Rioli, V; Oliveira, V; Ferro, E S

    2006-01-13

    Recent findings from our laboratory suggest that intracellular peptides containing putative post-translational modification sites (i.e., phosphorylation) could regulate specific protein interactions. Here, we extend our previous observations showing that peptide phosphorylation changes the kinetic parameters of structurally related endopeptidase EP24.15 (EC 3.4.24.15), neurolysin (EC 3.4.24.16), and angiotensin-converting enzyme (EC 3.4.15.1). Phosphorylation of peptides that are degraded by these enzymes leads to reduced degradation, whereas phosphorylation of peptides that interacted as competitive inhibitors of these enzymes alters only the K(i)'s. These data suggest that substrate phosphorylation could be one of the mechanisms whereby some intracellular peptides would escape degradation and could be regulating protein interactions within cells.

  14. Histidine and Aspartic Acid Residues Important for Immunoglobulin G Endopeptidase Activity of the Group A Streptococcus Opsonophagocytosis-Inhibiting Mac Protein

    Science.gov (United States)

    Lei, Benfang; Liu, Mengyao; Meyers, Elishia G.; Manning, Heather M.; Nagiec, Michael J.; Musser, James M.

    2003-01-01

    The secreted Mac protein made by serotype M1 group A Streptococcus (GAS) (designated Mac5005) inhibits opsonophagocytosis and killing of GAS by human polymorphonuclear neutrophils. This protein also has cysteine endopeptidase activity against human immunoglobulin G (IgG). Site-directed mutagenesis was used to identify histidine and aspartic acid residues important for Mac IgG endopeptidase activity. Replacement of His262 with Ala abolished Mac5005 IgG endopeptidase activity. Asp284Ala and Asp286Ala mutant proteins had compromised enzymatic activity, whereas 21 other Asp-to-Ala mutant proteins cleaved human IgG at the apparent wild-type level. The results suggest that His262 is an active-site residue and that Asp284 and Asp286 are important for the enzymatic activity or structure of Mac protein. These Mac mutants provide new information about structure-activity relationships in this protein and will assist study of the mechanism of inhibition of opsonophagocytosis and killing of GAS by Mac. PMID:12704162

  15. In vivo multiplex quantitative analysis of 3 forms of alpha melanocyte stimulating hormone in pituitary of prolyl endopeptidase deficient mice

    Directory of Open Access Journals (Sweden)

    Perroud Bertrand

    2009-06-01

    Full Text Available Abstract Background In vitro reactions are useful to identify putative enzyme substrates, but in vivo validation is required to identify actual enzyme substrates that have biological meaning. To investigate in vivo effects of prolyl endopeptidase (PREP, a serine protease, on alpha melanocyte stimulating hormone (α-MSH, we developed a new mass spectrometry based technique to quantitate, in multiplex, the various forms of α-MSH. Methods Using Multiple Reaction Monitoring (MRM, we analyzed peptide transitions to quantify three different forms of α-MSH. Transitions were first confirmed using standard peptides. Samples were then analyzed by mass spectrometry using a triple quadrupole mass spectrometer, after elution from a reverse phase C18 column by a gradient of acetonitrile. Results We first demonstrate in vitro that PREP digests biological active alpha melanocyte stimulating hormone (α-MSH1–13, by cleaving the terminal amidated valine and releasing a truncated alpha melanocyte stimulating hormone (α-MSH1–12 product – the 12 residues α-MSH form. We then use the technique in vivo to analyze the MRM transitions of the three different forms of α-MSH: the deacetylated α-MSH1–13, the acetylated α-MSH1–13 and the truncated form α-MSH1–12. For this experiment, we used a mouse model (PREP-GT in which the serine protease, prolyl endopeptidase, is deficient due to a genetrap insertion. Here we report that the ratio between acetylated α-MSH1–13 and α-MSH1–12 is significantly increased (P-value = 0.015, N = 6 in the pituitaries of PREP-GT mice when compared to wild type littermates. In addition no significant changes were revealed in the relative level of α-MSH1–13 versus the deacetylated α-MSH1–13. These results combined with the demonstration that PREP digests α-MSH1–13 in vitro, strongly suggest that α-MSH1–13 is an in vivo substrate of PREP. Conclusion The multiplex targeted quantitative peptidomics technique we

  16. Cloning and characterization of the gene encoding the PepF endopeptidase from the aquatic bacterium Caulobacter crescentus

    Directory of Open Access Journals (Sweden)

    Braz Vânia S.

    2002-01-01

    Full Text Available The metallopeptidases have a very important role in bacteria, being involved in several processes that rely on protein turnover, such as nutrition, degradation of signal peptides, protein localization and virulence. We have cloned and characterized the gene of the metalloendopeptidase PepF from the aquatic bacterium Caulobacter crescentus. The gene upstream of pepF (orf1 encodes a conserved hypothetical protein found in Mycobacterium and Streptomyces. pepF is co-transcribed with the gene downstream (orf3, which encodes a protein that belongs to the ABC1 protein kinase family, suggesting that these two proteins may share a common function in the cell. The C. crescentus PepF protein possesses the conserved HEXGH motif present in zinc binding domains of PepF homologs. Disruption of the pepF gene by insertion of a vector sequence did not produced any growth defect, but the mutant strain possesses only 30% of the specific activity of endopeptidases present in the wild type strain. Deletions and point mutations in the regulatory region showed that there are two putative promoter regions, and the operon expression is independent of the transcription regulator CtrA. The results indicate that PepF is not essential for either growth or development of this bacterium using peptides as the sole carbon source, suggesting that other peptidases can be sharing this function.

  17. Bacteriocin protein BacL1 of Enterococcus faecalis is a peptidoglycan D-isoglutamyl-L-lysine endopeptidase.

    Science.gov (United States)

    Kurushima, Jun; Hayashi, Ikue; Sugai, Motoyuki; Tomita, Haruyoshi

    2013-12-27

    Enterococcus faecalis strains are commensal bacteria in humans and other animals, and they are also the causative agent of opportunistic infectious diseases. Bacteriocin 41 (Bac41) is produced by certain E. faecalis clinical isolates, and it is active against other E. faecalis strains. Our genetic analyses demonstrated that the extracellular products of the bacL1 and bacA genes, which are encoded in the Bac41 operon, coordinately express the bacteriocin activity against E. faecalis. In this study, we investigated the molecular functions of the BacL1 and BacA proteins. Immunoblotting and N-terminal amino acid sequence analysis revealed that BacL1 and BacA are secreted without any processing. The coincidental treatment with the recombinant BacL1 and BacA showed complete bacteriocin activity against E. faecalis, but neither BacL1 nor BacA protein alone showed the bacteriocin activity. Interestingly, BacL1 alone demonstrated substantial degrading activity against the cell wall fraction of E. faecalis in the absence of BacA. Furthermore, MALDI-TOF MS analysis revealed that BacL1 has a peptidoglycan D-isoglutamyl-L-lysine endopeptidase activity via a NlpC/P60 homology domain. These results collectively suggest that BacL1 serves as a peptidoglycan hydrolase and, when BacA is present, results in the lysis of viable E. faecalis cells.

  18. Alterations in plasma prolyl endopeptidase activity in depression, mania, and schizophrenia: effects of antidepressants, mood stabilizers, and antipsychotic drugs.

    Science.gov (United States)

    Maes, M; Goossens, F; Scharpé, S; Calabrese, J; Desnyder, R; Meltzer, H Y

    1995-10-16

    The activity of prolyl endopeptidase (PEP), a serine proteinase, has been found to be significantly lower in the blood of patients with major depression than in normal volunteers. The present study investigates plasma PEP activity in 25 major depressed, 10 manic, and 14 schizophrenic subjects versus 30 normal volunteers. It also examines the effects of antidepressants, valproate, and neuroleptic drugs on plasma PEP activity. PEP activity was significantly lower in major depressed subjects than in normal volunteers and in patients with mania and schizophrenia. In depressed subjects, plasma PEP activity was significantly increased during treatment with antidepressant drugs, such as fluoxetine. Plasma PEP activity was significantly increased in manic and schizophrenic subjects compared with normal volunteers. In manic subjects, short-term treatment with valproate had a significant suppressive effect on PEP activity. No significant effects of neuroleptics on PEP activity could be found in the schizophrenic patients. The results support the hypothesis that lower PEP activity could play a role in the pathophysiology of major depression, while increased PEP activity may be related to psychotic conditions, such as mania and schizophrenia.

  19. The mecillinam resistome reveals a role for peptidoglycan endopeptidases in stimulating cell wall synthesis in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Ghee Chuan Lai

    2017-07-01

    Full Text Available Bacterial cells are typically surrounded by an net-like macromolecule called the cell wall constructed from the heteropolymer peptidoglycan (PG. Biogenesis of this matrix is the target of penicillin and related beta-lactams. These drugs inhibit the transpeptidase activity of PG synthases called penicillin-binding proteins (PBPs, preventing the crosslinking of nascent wall material into the existing network. The beta-lactam mecillinam specifically targets the PBP2 enzyme in the cell elongation machinery of Escherichia coli. Low-throughput selections for mecillinam resistance have historically been useful in defining mechanisms involved in cell wall biogenesis and the killing activity of beta-lactam antibiotics. Here, we used transposon-sequencing (Tn-Seq as a high-throughput method to identify nearly all mecillinam resistance loci in the E. coli genome, providing a comprehensive resource for uncovering new mechanisms underlying PG assembly and drug resistance. Induction of the stringent response or the Rcs envelope stress response has been previously implicated in mecillinam resistance. We therefore also performed the Tn-Seq analysis in mutants defective for these responses in addition to wild-type cells. Thus, the utility of the dataset was greatly enhanced by determining the stress response dependence of each resistance locus in the resistome. Reasoning that stress response-independent resistance loci are those most likely to identify direct modulators of cell wall biogenesis, we focused our downstream analysis on this subset of the resistome. Characterization of one of these alleles led to the surprising discovery that the overproduction of endopeptidase enzymes that cleave crosslinks in the cell wall promotes mecillinam resistance by stimulating PG synthesis by a subset of PBPs. Our analysis of this activation mechanism suggests that, contrary to the prevailing view in the field, PG synthases and PG cleaving enzymes need not function in multi

  20. Serum activities of adenosine deaminase, dipeptidyl peptidase IV and prolyl endopeptidase in patients with fibromyalgia: diagnostic implications.

    Science.gov (United States)

    Čulić, Ognjen; Cordero, Mario D; Žanić-Grubišić, Tihana; Somborac-Bačura, Anita; Pučar, Lara Batičić; Detel, Dijana; Varljen, Jadranka; Barišić, Karmela

    2016-10-01

    Fibromyalgia (FM) is a chronic pain syndrome with number of symptoms that present challenge in terms of diagnosis and treatment. Patients with FM show abnormal profile of purines in plasma. In this work, we measured serum activities of enzymes involved in purine metabolism, namely total adenosine deaminase (ADE) and its isoforms (ADE1 and ADE2), ecto-ATPase, and 5'-nucleotidase (5'-NT). We also measured activity of dipeptidyl peptidase IV (DPPIV) and prolyl endopeptidase (PEP). Spectrophotometric and fluorometric methods were used for enzyme activity determinations. Enzyme activities were measured in sera of 24 patients with FM that were not undergoing pharmacological treatment during the study. Control group comprised 32 healthy control subjects. Significantly higher activities of total ADE (P = 0.025) and ADE2 (P = 0.011) were observed in FM patients, while no significant differences in ADE1, ecto-ATPase, and 5'-NT activities (P > 0.05) were found when compared to healthy controls. Moreover, increase in the activity of DPPIV (P = 0.015) and lower activity of PEP (P = 0.011) were also found in the FM group. ROC analysis pointed to different diagnostic sensitivities/specificities for individual enzyme activities measured as follows: ADE (50.0/87.5), ADE2 (41.7/90.6), DPPIV (62.5/71.9), and PEP (83.3/62.5). ADE2 and PEP were shown to be independent predictors of FM, while combination of the two gives AUC of 0.786 (95 % confidence interval of 0.656-0.885, P < 0.05). Our results are showing that serum activities of ADE2 and PEP could be useful as biomarkers for FM diagnosis. However, relatively low diagnostic sensitivity of ADE2 and specificity of PEP must be taken into account.

  1. Cigarette smoke-induced lung emphysema in mice is associated with prolyl endopeptidase, an enzyme involved in collagen breakdown

    Science.gov (United States)

    Koelink, Pim J.; Henricks, Paul A. J.; Jackson, Patricia L.; Nijkamp, Frans P.; Garssen, Johan; Kraneveld, Aletta D.; Blalock, J. Edwin; Folkerts, Gert

    2011-01-01

    There is increasing evidence that the neutrophil chemoattractant proline-glycine-proline (PGP), derived from the breakdown of the extracellular matrix, plays an important role in neutrophil recruitment to the lung. PGP formation is a multistep process involving neutrophils, metalloproteinases (MMPs), and prolyl endopeptidase (PE). This cascade of events is now investigated in the development of lung emphysema. A/J mice were whole body exposed to cigarette smoke for 20 wk. After 20 wk or 8 wk after smoking cessation, animals were killed, and bronchoalveolar lavage fluid and lung tissue were collected to analyze the neutrophilic airway inflammation, the MMP-8 and MMP-9 levels, the PE activity, and the PGP levels. Lung tissue degradation was assessed by measuring the mean linear intercept. Additionally, we investigated the effect of the peptide l-arginine-threonine-arginine (RTR), which binds to PGP sequences, on the smoke-induced neutrophil influx in the lung after 5 days of smoke exposure. Neutrophilic airway inflammation was induced by cigarette smoke exposure. MMP-8 and MMP-9 levels, PE activity, and PGP levels were elevated in the lungs of cigarette smoke-exposed mice. PE was highly expressed in epithelial and inflammatory cells (macrophages and neutrophils) in lung tissue of cigarette smoke-exposed mice. After smoking cessation, the neutrophil influx, the MMP-8 and MMP-9 levels, the PE activity, and the PGP levels were decreased or reduced to normal levels. Moreover, RTR inhibited the smoke-induced neutrophil influx in the lung after 5 days' smoke exposure. In the present murine model of cigarette smoke-induced lung emphysema, it is demonstrated for the first time that all relevant components (neutrophils, MMP-8, MMP-9, PE) involved in PGP formation from collagen are upregulated in the airways. Together with MMPs, PE may play an important role in the formation of PGP and thus in the pathophysiology of lung emphysema. PMID:21112944

  2. Dual neural endopeptidase/endothelin-converting [corrected] enzyme inhibition improves endothelial function in mesenteric resistance arteries of young spontaneously hypertensive rats

    DEFF Research Database (Denmark)

    Lemkens, Pieter; Nelissen, Jelly; Meens, Merlijn J P M T;

    2012-01-01

    through cleavage of big ET1 by endothelin-converting enzyme (ECE) and neutral endopeptidase (NEP). METHOD: We investigated whether the dual NEP/ECE inhibitor SOL1 improves resistance artery function and structure in 12 weeks old spontaneously hypertensive rats (SHRs) and whether arterial structural...... responses to decreased (-90%) or increased (+100%) blood flow are impaired in young SHRs. To this end two groups of SHRs received chronic 4-week treatment at two different time points (4-8 and 8-12 weeks) prior to the experiment. We compared in-vitro effects of cyclo-oxygenase inhibition (1 μmol...

  3. Interactions between neutral endopeptidase (EC 3.4.24.11) and the substance P (NK1) receptor expressed in mammalian cells.

    OpenAIRE

    Okamoto, A.; Lovett, M; Payan, D G; Bunnett, N W

    1994-01-01

    Interactions between neutral endopeptidase-24.11 (NEP) and the substance P receptor (SPR; NK1) were investigated by examining substance P (SP) degradation, SP binding and SP-induced Ca2+ mobilization in epithelial cells transfected with cDNA encoding the rat SPR and rat NEP. Expression of NEP accelerated the degradation of SP by intact epithelial cells and by membrane preparations, and degradation was reduced by the NEP inhibitor thiorphan. In cells expressing SPR alone, specific 125I-SP bind...

  4. Effect of endopeptidase-24.11 inhibitors and C-ANP receptor ligand on responses evoked in arterioles of rat cremaster muscle by atrial natriuretic peptide.

    OpenAIRE

    Peyroux, J.; Beslot, F.; Claperon, N; Fournie-Zaluski, M C; Roques, B P

    1995-01-01

    1. The present study examined the effect of exogenous atrial natriuretric peptide (ANP), alone or in presence of inhibitors of the two major mechanisms for clearing ANP, metabolism by neutral endopeptidase-24.11 (NEP) and internalization by C-ANP receptors, on arteriolar responses using intravital microscopy on the rat cremaster muscle after intravenous or topical administration of the peptide. 2. Topical application of ANP (3 x 10(-10) to 3 x 10(-8) M) produced a gradual increase in arteriol...

  5. Endoplasmic reticulum KDEL-tailed cysteine endopeptidase 1 of Arabidopsis (AtCEP1 is involved in pathogen defense

    Directory of Open Access Journals (Sweden)

    Timo eHöwing

    2014-02-01

    Full Text Available Programmed cell death (PCD is a genetically determined process in all multicellular organisms. Plant PCD is effected by a unique group of papain-type cysteine endopeptidases (CysEP with a C-terminal KDEL endoplasmic reticulum (ER retention signal (KDEL CysEP. KDEL CysEPs can be stored as pro-enzymes in ER-derived endomembrane compartments and are released as mature CysEPs in the final stages of organelle disintegration. KDEL CysEPs accept a wide variety of amino acids at the active site, including the glycosylated hydroxyprolines of the extensins that form the basic scaffold of the cell wall. In Arabidopsis, three KDEL CysEPs (AtCEP1, AtCEP2, and AtCEP3 are expressed. Cell- and tissue-specific activities of these three genes suggest that KDEL CysEPs participate in the abscission of flower organs and in the collapse of tissues in the final stage of PCD as well as in developmental tissue remodelling.We observed that AtCEP1 is expressed in response to biotic stress stimuli in the leaf. atcep1 knockout mutants showed enhanced susceptibility to powdery mildew caused by the biotrophic ascomycete Erysiphe cruciferarum. A translational fusion protein of AtCEP1 with a three-fold hemaglutinin-tag and the green fluorescent protein under control of the endogenous AtCEP1 promoter (PCEP1::pre-pro-3xHA-EGFP-AtCEP1-KDEL rescued the pathogenesis phenotype demonstrating the function of AtCEP1 in restriction of powdery mildew. The spatiotemporal AtCEP1-reporter expression during fungal infection together with microscopic inspection of the interaction phenotype suggested a function of AtCEP1 in controlling late stages of compatible interaction including late epidermal cell death. Additionally, expression of stress response genes appeared to be deregulated in the interaction of atcep1 mutants and E. cruciferarum. Possible functions of AtCEP1 in restricting parasitic success of the obligate biotrophic powdery mildew fungus are discussed.

  6. Prognostic significance of the combined expression of neutral endopeptidase and dipeptidyl peptidase IV in intrahepatic cholangiocarcinoma patients after surgery resection

    Directory of Open Access Journals (Sweden)

    Zhu JY

    2014-02-01

    Full Text Available Jianyong Zhu,1,* XiaoDong Guo,2,* Baoan Qiu,1 Zhiyan Li,2 Nianxin Xia,1 Yingxiang Yang,1 Peng Liu1 1Department of Hepatobiliary Surgery, Navy General Hospital, PLA, Beijing, People's Republic of China; 2302 Hospital of PLA, Beijing, People's Republic of China *These authors contributed equally to this work Aim: The aim of this study was to investigate the relationship between the expression of neutral endopeptidase (NEP and dipeptidyl peptidase IV (DPP IV proteins, and the clinical significance of the two proteins in patients with intrahepatic cholangiocarcinomas (IHCC. Methods: Expression patterns and subcellular localizations of NEP and DPP IV proteins in 186 primary IHCC and 60 noncancerous liver tissue specimens were detected by immunohistochemistry. Results: Both the expression of NEP and DPP IV proteins in IHCC tissues were significantly higher than those in noncancerous liver tissues (both P<0.001. Of 186 patients with IHCC, 128 (68.82% highly expressed both NEP and DPP IV proteins. In addition, the coexpression of NEP and DPP IV proteins was significantly associated with advanced tumor stage (P=0.009, positive lymph node metastasis (P=0.016 and distant metastasis (P=0.013, and the presence of recurrence (P=0.027. Moreover, Kaplan–Meier analysis showed that IHCC patients with high NEP expression, high DPP IV expression, and combined overexpression of NEP and DPP IV proteins all had poorer overall survival and early recurrence after surgery. Furthermore, Cox analysis suggested that NEP expression, DPP IV expression, and combined expression of NEP and DPP IV proteins were all independent prognostic markers for overall survival and recurrence-free survival in patients with IHCC. Conclusion: Our data suggest, for the first time, that both the expression of NEP and DPP IV proteins may be upregulated in human IHCC tissues and the combined expression of NEP and DPP IV proteins may play important roles in progression and prognosis of patients

  7. Bm-CPI-2, a cystatin from Brugia malayi nematode parasites, differs from Caenorhabditis elegans cystatins in a specific site mediating inhibition of the antigen-processing enzyme AEP.

    Science.gov (United States)

    Murray, Janice; Manoury, Bénédicte; Balic, Adam; Watts, Colin; Maizels, Rick M

    2005-02-01

    The filarial parasite Brugia malayi survives for many years in the human lymphatic system. One immune evasion mechanism employed by Brugia is thought to be the release of cysteine protease inhibitors (cystatins), and we have previously shown that the recombinant cystatin Bm-CPI-2 interferes with protease-dependent antigen processing in the MHC class II antigen presentation pathway. Analogy with vertebrate cystatins suggested that Bm-CPI-2 is bi-functional, with one face of the protein blocking papain-like proteases, and the other able to inhibit legumains such as asparaginyl endopeptidase (AEP). Site-directed mutagenesis was carried out on Bm-CPI-2 at Asn-77, the residue on which AEP inhibition is dependent in vertebrate homologues. Two mutations at this site (to Asp and Lys) showed 10-fold diminished and ablated activity respectively, in assays of AEP inhibition, while blocking of papain-like proteases was reduced by only a small degree. Comparison of the B. malayi cystatins with two homologues encoded by the free-living model organism, Caenorhabditis elegans, suggested that while the papain site may be intact, the AEP site would not be functional. This supposition was tested with recombinant C. elegans proteins, Ce-CPI-1 (K08B4.6) and Ce-CPI-2 (R01B10.1), both of which block cathepsins and neither of which possess the ability to block AEP. Thus, Brugia CPI-2 may have convergently evolved to inhibit an enzyme important only in the mammalian environment.

  8. Synthesis of (N-[[sup 11]C]methyl)Y-29794, a competitive inhibitor of prolyl endopeptidase. [2-(8-dimethylaminoctylthio)-6-isopropyl-3-pyridyl-2-thienyl ketone

    Energy Technology Data Exchange (ETDEWEB)

    Charalambous, A.; Mangner, T.J.; Kilbourn, M.R. (Michigan Univ., Ann Arbor, MI (United States). Div. of Nuclear Medicine)

    1994-06-01

    Prolyl endopeptidase (PEP:[E.C.3.4.21.26]) is a widely distributed serine peptidase that cleaves a variety of oligopeptides in the brain and peripheral tissues. Y-29794 2-(8-dimethylaminooctylthio)-(6-isopropyl-3-pyridyl-2-thienyl ketone) is a potent competitive reversible inhibitor of this enzyme. In order to study the biodistribution of PEP in vivo we have synthesized (N[[sup 11]C]methyl)Y-29794, by [[sup 11]C]alkylation of the N-desmethyl precursor. The radiotracer was purified by silica gel Sep-Pak and was obtained in 10-17% yields (EOB: synthesis times shorter than 45 min) with >98% radiochemical purities and specific activities >550 Ci/mmol (EOS). (Author).

  9. Effects of a Proline Endopeptidase on the Detection and Quantitation of Gluten by Antibody-Based Methods during the Fermentation of a Model Sorghum Beer.

    Science.gov (United States)

    Panda, Rakhi; Fiedler, Katherine L; Cho, Chung Y; Cheng, Raymond; Stutts, Whitney L; Jackson, Lauren S; Garber, Eric A E

    2015-12-09

    The effectiveness of a proline endopeptidase (PEP) in hydrolyzing gluten and its putative immunopathogenic sequences was examined using antibody-based methods and mass spectrometry (MS). Based on the results of the antibody-based methods, fermentation of wheat gluten containing sorghum beer resulted in a reduction in the detectable gluten concentration. The addition of PEP further reduced the gluten concentration. Only one sandwich ELISA was able to detect the apparent low levels of gluten present in the beers. A competitive ELISA using a pepsin-trypsin hydrolysate calibrant was unreliable because the peptide profiles of the beers were inconsistent with that of the hydrolysate calibrant. Analysis by MS indicated that PEP enhanced the loss of a fragment of an immunopathogenic 33-mer peptide in the beer. However, Western blot results indicated partial resistance of the high molecular weight (HMW) glutenins to the action of PEP, questioning the ability of PEP in digesting all immunopathogenic sequences present in gluten.

  10. Multiple cathepsin B isoforms in schistosomula of Trichobilharzia regenti: identification, characterisation and putative role in migration and nutrition.

    Science.gov (United States)

    Dvorák, Jan; Delcroix, Melaine; Rossi, Andrea; Vopálenský, Václav; Pospísek, Martin; Sedinová, Miroslava; Mikes, Libor; Sajid, Mohammed; Sali, Andrej; McKerrow, James H; Horák, Petr; Caffrey, Conor R

    2005-07-01

    Among schistosomatids, Trichobilharzia regenti, displays an unusual migration through the peripheral and central nervous system prior to residence in the nasal cavity of the definitive avian host. Migration causes tissue degradation and neuromotor dysfunction both in birds and experimentally infected mice. Although schistosomula have a well-developed gut, the peptidases elaborated that might facilitate nutrition and migration are unknown. This is, in large part, due to the difficulty in isolating large numbers of migrating larvae. We have identified and characterised the major 33 kDa cathepsin B-like cysteine endopeptidase in extracts of migrating schistosomula using fluorogenic peptidyl substrates with high extinction coefficients and irreversible affinity-labels. From first strand schistosomula cDNA, degenerate PCR and Rapid Amplification of cDNA End protocols were used to identify peptidase isoforms termed TrCB1.1-TrCB1.6. Highest sequence homology is to the described Schistosoma mansoni and Schistosoma japonicum cathepsins B1. Two isoforms (TrCB1.5 and 1.6) encode putatively inactive enzymes as the catalytic cysteine is substituted by glycine. Two other isoforms, TrCB1.1 and 1.4, were functionally expressed as zymogens in Pichia pastoris. Specific polyclonal antibodies localised the peptidases exclusively in the gut of schistosomula and reacted with a 33kDa protein in worm extracts. TrCB1.1 zymogen was unable to catalyse its own activation, but was trans-processed and activated by S. mansoni asparaginyl endopeptidase (SmAE aka. S. mansoni legumain). In contrast, TrCB1.4 zymogen auto-activated, but was resistant to the action of SmAE. Both activated isoforms displayed different pH-dependent specificity profiles with peptidyl substrates. Also, both isoforms degraded myelin basic protein, the major protein component of nervous tissue, but were inefficient against hemoglobin, thus supporting the adaptation of T. regenti gut peptidases to parasitism of host nervous

  11. Analysis of the peptidoglycan hydrolase complement of Lactobacillus casei and characterization of the major γ-D-glutamyl-L-lysyl-endopeptidase.

    Directory of Open Access Journals (Sweden)

    Krzysztof Regulski

    Full Text Available Peptidoglycan (PG is the major component of Gram positive bacteria cell wall and is essential for bacterial integrity and shape. Bacteria synthesize PG hydrolases (PGHs which are able to cleave bonds in their own PG and play major roles in PG remodelling required for bacterial growth and division. Our aim was to identify the main PGHs in Lactobacillus casei BL23, a lactic acid bacterium with probiotic properties.The PGH complement was first identified in silico by amino acid sequence similarity searches of the BL23 genome sequence. Thirteen PGHs were detected with different predicted hydrolytic specificities. Transcription of the genes was confirmed by RT-PCR. A proteomic analysis combining the use of SDS-PAGE and LC-MS/MS revealed the main seven PGHs synthesized during growth of L. casei BL23. Among these PGHs, LCABL_02770 (renamed Lc-p75 was identified as the major one. This protein is the homolog of p75 (Msp1 major secreted protein of Lactobacillus rhamnosus GG, which was shown to promote survival and growth of intestinal epithelial cells. We identified its hydrolytic specificity on PG and showed that it is a γ-D-glutamyl-L-lysyl-endopeptidase. It has a marked specificity towards PG tetrapeptide chains versus tripeptide chains and for oligomers rather than monomers. Immunofluorescence experiments demonstrated that Lc-p75 localizes at cell septa in agreement with its role in daughter cell separation. It is also secreted under an active form as detected in zymogram. Comparison of the muropeptide profiles of wild type and Lc-p75-negative mutant revealed a decrease of the amount of disaccharide-dipeptide in the mutant PG in agreement with Lc-p75 activity. As a conclusion, Lc-p75 is the major L. casei BL23 PGH with endopeptidase specificity and a key role in daughter cell separation. Further studies will aim at investigating the role of Lc-p75 in the anti-inflammatory potential of L. casei BL23.

  12. Multifunctional amaranth cystatin inhibits endogenous and digestive insect cysteine endopeptidases: A potential tool to prevent proteolysis and for the control of insect pests.

    Science.gov (United States)

    Valdés-Rodríguez, Silvia; Galván-Ramírez, Juan Pablo; Guerrero-Rangel, Armando; Cedro-Tanda, Alberto

    2015-01-01

    In a previous study, the amaranth cystatin was characterized. This cystatin is believed to provide protection from abiotic stress because its transcription is induced in response to heat, drought, and salinity. It has also been shown that recombinant amaranth cystatin inhibits bromelain, ficin, and cysteine endopeptidases from fungal sources and also inhibits the growth of phytopathogenic fungi. In the present study, evidence is presented regarding the potential function of amaranth cystatin as a regulator of endogenous proteinases and insect digestive proteinases. During amaranth germination and seedling growth, different proteolytic profiles were observed at different pH levels in gelatin-containing SDS-PAGE. Most of the proteolytic enzymes detected at pH 4.5 were mainly inhibited by trans-epoxysuccinyl-leucyl amido(4-guanidino)butane (E-64) and the purified recombinant amaranth cystatin. Furthermore, the recombinant amaranth cystatin was active against insect proteinases. In particular, the E-64-sensitive proteolytic digestive enzymes from Callosobruchus maculatus, Zabrotes subfasciatus, and Acanthoscelides obtectus were inhibited by the amaranth cystatin. Taken together, these results suggest multiple roles for cystatin in amaranth, specifically during germination and seedling growth and in the protection of A. hypochondriacus against insect predation. Amaranth cystatin represents a promising tool for diverse applications in the control of insect pest and for preventing undesirable proteolytic activity.

  13. Cytoplasmic expression of mature glycylglycine endopeptidase lysostaphin with an amino terminal hexa-histidine in a soluble and catalytically active form in Escherichia coli.

    Science.gov (United States)

    Sharma, Rahul; Sharma, Poonam R; Choudhary, Manohar L; Pande, Amit; Khatri, Ghan Shyam

    2006-01-01

    Methicillin-resistant Staphylococcus aureus is a major problem in the world, causing hospital acquired infections and the infections/pathogenesis in community. Lysostaphin is a novel therapeutic molecule to kill the multidrug-resistant S. aureus. Mature lysostaphin is a single polypeptide (approximately 27 kDa) chain metalloprotease glycylglycine endopeptidase, capable of specifically hydrolyzing penta-glycine crosslinks present in the peptidoglycan of the S. aureus cell wall. The mature lysostaphin gene of Staphylococcus simulans has been cloned and overexpressed in the cytoplasm of E. coli with amino terminal hexa-histidine as a fusion partner under the transcriptional control of bacteriophage T7 phi 10 promoter/lac operator and ribosome binding site. The transformed E. coli BL21 (lambdaDE3) cells produced catalytically active soluble (His)6-lysostaphin fusion protein in the cytoplasm representing approximately 20% of the total cellular proteins. The fusion protein was purified to homogeneity using a single chromatographic step of IMAC on Ni-NTA agarose. The present cloning, expression, and purification procedure of recombinant lysostaphin from a non-pathogenic organism E. coli enables preparation of large quantity of r-lysostaphin for structure function studies and evaluation of its clinical potential in therapy and prophylaxis of staphylococcal infections.

  14. Effect of pre-treatment on the generation of dipeptidyl peptidase-IV- and prolyl endopeptidase-inhibitory hydrolysates from bovine lung

    Directory of Open Access Journals (Sweden)

    Lafarga T.

    2017-05-01

    Full Text Available The aim of this work was to study the effect of two different pre-treatments, high temperature (100 °C, 5 min and high pressure (600 MPa, 3 min, on the potential of the enzymes papain, collagenase and Alcalase® to generate bioactive hydrolysates containing dipeptidyl peptidase-IV- (DPP-IV; EC 3.4.14.5 and prolyl endopeptidase- (PEP; EC 3.4.21.26 inhibitory peptides from bovine lung. Both pre-treatments resulted in an increase in the degree of hydrolysis over a 24 h period (P < 0.001 and significantly increased the DPP-IV- and PEP-inhibitory activities of the generated hydrolysates (P < 0.001. Generated hydrolysates included an Alcalase hydrolysate of pressure-treated bovine lung, which was the most active, and showed DPP-IV and PEP half-maximal inhibitory concentration (IC50 values of 1.43 ± 0.06 and 3.62 ± 0.07 mg/ mL, respectively. The major peptides contained in this hydrolysate were determined by liquid chromatography-tandem mass spectrometry, and results demonstrated that bovine lung is a good substrate for the release of bioactive peptides when proper pre-treatment and enzymatic treatment are applied.

  15. Binding of Streptococcus pneumoniae endopeptidase O (PepO) to complement component C1q modulates the complement attack and promotes host cell adherence.

    Science.gov (United States)

    Agarwal, Vaibhav; Sroka, Magdalena; Fulde, Marcus; Bergmann, Simone; Riesbeck, Kristian; Blom, Anna M

    2014-05-30

    The Gram-positive species Streptococcus pneumoniae is a human pathogen causing severe local and life-threatening invasive diseases associated with high mortality rates and death. We demonstrated recently that pneumococcal endopeptidase O (PepO) is a ubiquitously expressed, multifunctional plasminogen and fibronectin-binding protein facilitating host cell invasion and evasion of innate immunity. In this study, we found that PepO interacts directly with the complement C1q protein, thereby attenuating the classical complement pathway and facilitating pneumococcal complement escape. PepO binds both free C1q and C1 complex in a dose-dependent manner based on ionic interactions. Our results indicate that recombinant PepO specifically inhibits the classical pathway of complement activation in both hemolytic and complement deposition assays. This inhibition is due to direct interaction of PepO with C1q, leading to a strong activation of the classical complement pathway, and results in consumption of complement components. In addition, PepO binds the classical complement pathway inhibitor C4BP, thereby regulating downstream complement activation. Importantly, pneumococcal surface-exposed PepO-C1q interaction mediates bacterial adherence to host epithelial cells. Taken together, PepO facilitates C1q-mediated bacterial adherence, whereas its localized release consumes complement as a result of its activation following binding of C1q, thus representing an additional mechanism of human complement escape by this versatile pathogen.

  16. Toll-like receptor 5 (TLR5), IL-1β secretion, and asparagine endopeptidase are critical factors for alveolar macrophage phagocytosis and bacterial killing.

    Science.gov (United States)

    Descamps, Delphyne; Le Gars, Mathieu; Balloy, Viviane; Barbier, Diane; Maschalidi, Sophia; Tohme, Mira; Chignard, Michel; Ramphal, Reuben; Manoury, Bénédicte; Sallenave, Jean-Michel

    2012-01-31

    A deficit in early clearance of Pseudomonas aeruginosa (P. aeruginosa) is crucial in nosocomial pneumonia and in chronic lung infections. Few studies have addressed the role of Toll-like receptors (TLRs), which are early pathogen associated molecular pattern receptors, in pathogen uptake and clearance by alveolar macrophages (AMs). Here, we report that TLR5 engagement is crucial for bacterial clearance by AMs in vitro and in vivo because unflagellated P. aeruginosa or different mutants defective in TLR5 activation were resistant to AM phagocytosis and killing. In addition, the clearance of PAK (a wild-type P. aeruginosa strain) by primary AMs was causally associated with increased IL-1β release, which was dramatically reduced with PAK mutants or in WT PAK-infected primary TLR5(-/-) AMs, demonstrating the dependence of IL-1β production on TLR5. We showed that this IL-1β production was important in endosomal pH acidification and in inducing the killing of bacteria by AMs through asparagine endopeptidase (AEP), a key endosomal cysteine protease. In agreement, AMs from IL-1R1(-/-) and AEP(-/-) mice were unable to kill P. aeruginosa. Altogether, these findings demonstrate that TLR5 engagement plays a major role in P. aeruginosa internalization and in triggering IL-1β formation.

  17. Abundance of cysteine endopeptidase dionain in digestive fluid of Venus flytrap (Dionaea muscipula Ellis is regulated by different stimuli from prey through jasmonates.

    Directory of Open Access Journals (Sweden)

    Michaela Libiaková

    Full Text Available The trap of the carnivorous plant Venus flytrap (Dionaea muscipula catches prey by very rapid closure of its modified leaves. After the rapid closure secures the prey, repeated mechanical stimulation of trigger hairs by struggling prey and the generation of action potentials (APs result in secretion of digestive fluid. Once the prey's movement stops, the secretion is maintained by chemical stimuli released from digested prey. We investigated the effect of mechanical and chemical stimulation (NH4Cl, KH2PO4, further N(Cl and P(K stimulation on enzyme activities in digestive fluid. Activities of β-D-glucosidases and N-acetyl-β-D-glucosaminidases were not detected. Acid phosphatase activity was higher in N(Cl stimulated traps while proteolytic activity was higher in both chemically induced traps in comparison to mechanical stimulation. This is in accordance with higher abundance of recently described enzyme cysteine endopeptidase dionain in digestive fluid of chemically induced traps. Mechanical stimulation induced high levels of cis-12-oxophytodienoic acid (cis-OPDA but jasmonic acid (JA and its isoleucine conjugate (JA-Ile accumulated to higher level after chemical stimulation. The concentration of indole-3-acetic acid (IAA, salicylic acid (SA and abscisic acid (ABA did not change significantly. The external application of JA bypassed the mechanical and chemical stimulation and induced a high abundance of dionain and proteolytic activity in digestive fluid. These results document the role of jasmonates in regulation of proteolytic activity in response to different stimuli from captured prey. The double trigger mechanism in protein digestion is proposed.

  18. Abundance of cysteine endopeptidase dionain in digestive fluid of Venus flytrap (Dionaea muscipula Ellis) is regulated by different stimuli from prey through jasmonates.

    Science.gov (United States)

    Libiaková, Michaela; Floková, Kristýna; Novák, Ondřej; Slováková, L'udmila; Pavlovič, Andrej

    2014-01-01

    The trap of the carnivorous plant Venus flytrap (Dionaea muscipula) catches prey by very rapid closure of its modified leaves. After the rapid closure secures the prey, repeated mechanical stimulation of trigger hairs by struggling prey and the generation of action potentials (APs) result in secretion of digestive fluid. Once the prey's movement stops, the secretion is maintained by chemical stimuli released from digested prey. We investigated the effect of mechanical and chemical stimulation (NH4Cl, KH2PO4, further N(Cl) and P(K) stimulation) on enzyme activities in digestive fluid. Activities of β-D-glucosidases and N-acetyl-β-D-glucosaminidases were not detected. Acid phosphatase activity was higher in N(Cl) stimulated traps while proteolytic activity was higher in both chemically induced traps in comparison to mechanical stimulation. This is in accordance with higher abundance of recently described enzyme cysteine endopeptidase dionain in digestive fluid of chemically induced traps. Mechanical stimulation induced high levels of cis-12-oxophytodienoic acid (cis-OPDA) but jasmonic acid (JA) and its isoleucine conjugate (JA-Ile) accumulated to higher level after chemical stimulation. The concentration of indole-3-acetic acid (IAA), salicylic acid (SA) and abscisic acid (ABA) did not change significantly. The external application of JA bypassed the mechanical and chemical stimulation and induced a high abundance of dionain and proteolytic activity in digestive fluid. These results document the role of jasmonates in regulation of proteolytic activity in response to different stimuli from captured prey. The double trigger mechanism in protein digestion is proposed.

  19. Genetic homogeneity but IgG subclass-dependent clinical variability of alloimmune membranous nephropathy with anti-neutral endopeptidase antibodies.

    Science.gov (United States)

    Vivarelli, Marina; Emma, Francesco; Pellé, Thimothée; Gerken, Christopher; Pedicelli, Stefania; Diomedi-Camassei, Francesca; Klaus, Günter; Waldegger, Siegfried; Ronco, Pierre; Debiec, Hanna

    2015-03-01

    Alloimmune antenatal membranous nephropathy (MN) during pregnancy results from antibodies produced by a neutral endopeptidase (NEP)-deficient mother. Here we report two recent cases that provide clues to the severity of renal disease. Mothers of the two children had circulating antibodies against NEP showing the characteristic species-dependent pattern by immunofluorescence on kidney slices. A German mother produced predominantly anti-NEP IgG4 accompanied by a low amount of IgG1. Her child recovered renal function within a few weeks. In sharp contrast, an Italian mother mainly produced complement-fixing anti-NEP IgG1, which also inhibits NEP enzymatic activity, whereas anti-NEP IgG4 has a weak inhibitory potency. Her child was dialyzed for several weeks. A kidney biopsy performed at 12 days of age showed MN, ischemic glomeruli, and arteriolar and tubular lesions. A second biopsy performed at 12 weeks of age showed aggravation with an increased number of collapsed capillary tufts. Both mothers were homozygous for the truncating deletion mutation 466delC and were thus NEP deficient. The 466delC mutation, identified in three previously described families, suggests a founder effect. Because of the potential severity of alloimmune antenatal MN, it is essential to identify families at risk by the detection of anti-NEP antibodies and NEP antigen in urine. On the basis of the five families identified to date, we propose an algorithm for the diagnosis of the disease and the prevention of complications.

  20. Streptococcus pyogenes Endopeptidase O Contributes to Evasion from Complement-mediated Bacteriolysis via Binding to Human Complement Factor C1q.

    Science.gov (United States)

    Honda-Ogawa, Mariko; Sumitomo, Tomoko; Mori, Yasushi; Hamd, Dalia Talat; Ogawa, Taiji; Yamaguchi, Masaya; Nakata, Masanobu; Kawabata, Shigetada

    2017-03-10

    Streptococcus pyogenes secretes various virulence factors for evasion from complement-mediated bacteriolysis. However, full understanding of the molecules possessed by this organism that interact with complement C1q, an initiator of the classical complement pathway, remains elusive. In this study, we identified an endopeptidase of S. pyogenes, PepO, as an interacting molecule, and investigated its effects on complement immunity and pathogenesis. Enzyme-linked immunosorbent assay and surface plasmon resonance analysis findings revealed that S. pyogenes recombinant PepO bound to human C1q in a concentration-dependent manner under physiological conditions. Sites of inflammation are known to have decreased pH levels, thus the effects of PepO on bacterial evasion from complement immunity was analyzed in a low pH condition. Notably, under low pH conditions, PepO exhibited a higher affinity for C1q as compared with IgG, and PepO inhibited the binding of IgG to C1q. In addition, pepO deletion rendered S. pyogenes more susceptible to the bacteriocidal activity of human serum. Also, observations of the morphological features of the pepO mutant strain (ΔpepO) showed damaged irregular surfaces as compared with the wild-type strain (WT). WT-infected tissues exhibited greater severity and lower complement activity as compared with those infected by ΔpepO in a mouse skin infection model. Furthermore, WT infection resulted in a larger accumulation of C1q than that with ΔpepO. Our results suggest that interaction of S. pyogenes PepO with C1q interferes with the complement pathway, which enables S. pyogenes to evade complement-mediated bacteriolysis under acidic conditions, such as seen in inflammatory sites. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Potent new small-molecule inhibitor of botulinum neurotoxin serotype A endopeptidase developed by synthesis-based computer-aided molecular design.

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    Yuan-Ping Pang

    Full Text Available Botulinum neurotoxin serotype A (BoNTA causes a life-threatening neuroparalytic disease known as botulism. Current treatment for post exposure of BoNTA uses antibodies that are effective in neutralizing the extracellular toxin to prevent further intoxication but generally cannot rescue already intoxicated neurons. Effective small-molecule inhibitors of BoNTA endopeptidase (BoNTAe are desirable because such inhibitors potentially can neutralize the intracellular BoNTA and offer complementary treatment for botulism. Previously we reported a serotype-selective, small-molecule BoNTAe inhibitor with a K(i (app value of 3.8+/-0.8 microM. This inhibitor was developed by lead identification using virtual screening followed by computer-aided optimization of a lead with an IC(50 value of 100 microM. However, it was difficult to further improve the lead from micromolar to even high nanomolar potency due to the unusually large enzyme-substrate interface of BoNTAe. The enzyme-substrate interface area of 4,840 A(2 for BoNTAe is about four times larger than the typical protein-protein interface area of 750-1,500 A(2. Inhibitors must carry several functional groups to block the unusually large interface of BoNTAe, and syntheses of such inhibitors are therefore time-consuming and expensive. Herein we report the development of a serotype-selective, small-molecule, and competitive inhibitor of BoNTAe with a K(i value of 760+/-170 nM using synthesis-based computer-aided molecular design (SBCAMD. This new approach accounts the practicality and efficiency of inhibitor synthesis in addition to binding affinity and selectivity. We also report a three-dimensional model of BoNTAe in complex with the new inhibitor and the dynamics of the complex predicted by multiple molecular dynamics simulations, and discuss further structural optimization to achieve better in vivo efficacy in neutralizing BoNTA than those of our early micromolar leads. This work provides new insight

  2. Treatment of both native and deamidated gluten peptides with an endo-peptidase from Aspergillus niger prevents stimulation of gut-derived gluten-reactive T cells from either children or adults with celiac disease

    DEFF Research Database (Denmark)

    Toft-Hansen, Henrik; Rasmussen, Karina Søndergård; Nielsen, Anne Staal

    2014-01-01

    Celiac disease (CD) is characterized by an inappropriate immunological reaction against gluten driven by gluten-specific CD4+ T cells. We screened 25 proteases and tested 10 for their potential to degrade gluten in vitro. Five proteases were further tested for their ability to prevent...... the proliferative response by a gluten-specific CD4+ T cell clone and seven gluten-reactive T cell lines to protease-digested gluten peptides. A proline-specific endo-peptidase from Aspergillus niger (AnP2), was particularly efficient at diminishing proliferation after stimulation with cleaved antigen, and could...... completely block the response against both native and deamidated gluten peptides. We found that AnP2 was efficient down to a 1:64 protease:substrate ratio (w:w). When AnP2 was tested in assays using seven gluten-reactive T cell lines from individual CD patients (three adults and four children), the response...

  3. Synthesis of N-[l brace]N-[4-(4-[l brace]N-[[sup 11]C]methylamino[r brace]phenyl)butyryl]-L-prolyl[r brace]pyrrolidine: a potential radiotracer for prolyl endopeptidase

    Energy Technology Data Exchange (ETDEWEB)

    Dort, M.E. van; Kilbourn, M.R.; Mangner, T.J. (Michigan Univ., Ann Arbor, MI (United States). School of Medicine)

    1994-05-01

    The synthesis of the 4-[[sup 11]C]methylamino derivative of N-[l brace]N-[4-(4-Aminophenyl)butyryl]-L-proly[r brace]pyrrolidine (SUAM-1221), is described as a potential marker for prolyl endopeptidase for in vivo positron emission tomography studies. Direct methylation of the 4-amino derivative of SUAM-1221 (1) with methyl iodide provided a mixture of the 4-monomethyl (2) and 4-dimethylamino (3) derivatives which were separated by chromatography. Methylation of 1 with [[sup 11]C]methyl iodide provided the 4-[[sup 11]C]methylamino derivative of SUAM-1221, ([[sup 11]C]2), in 18-30% decay corrected radiochemical yield after HPLC purification, with a specific activity > 1700 Ci/mmol and a 40 minute synthesis time from end of bombardment. (author).

  4. Epigenetic Control of Prolyl and Asparaginyl Hydroxylases in Prostate Cancer

    Science.gov (United States)

    2011-07-01

    that PHD3 may have a direct impact on cellular metabolism, as opposed to an indirect effect through the hypoxia inducible factors (HIFs). To query if...hydrocarbon nuclear translocator receptor (ARNT/HIF-b)HIF-1a activates the transcription of EPO, VEGF, heme oxygenase-1 and several other critical...containing proteins (PHD/EGLN/HPH) which utilize iron , oxygen and 2-oxoglutarate as co-factors to enzymatically catalyze hydroxylation on the oxygen-dependent

  5. Treatment of both native and deamidated gluten peptides with an endo-peptidase from Aspergillus niger prevents stimulation of gut-derived gluten-reactive T cells from either children or adults with celiac disease.

    Science.gov (United States)

    Toft-Hansen, Henrik; Rasmussen, Karina S; Staal, Anne; Roggen, Erwin L; Sollid, Ludvig M; Lillevang, Søren T; Barington, Torben; Husby, Steffen

    2014-08-01

    Celiac disease (CD) is characterized by an inappropriate immunological reaction against gluten driven by gluten-specific CD4+ T cells. We screened 25 proteases and tested 10 for their potential to degrade gluten in vitro. Five proteases were further tested for their ability to prevent the proliferative response by a gluten-specific CD4+ T cell clone and seven gluten-reactive T cell lines to protease-digested gluten peptides. A proline-specific endo-peptidase from Aspergillus niger (AnP2) was particularly efficient at diminishing proliferation after stimulation with cleaved antigen, and could completely block the response against both native and deamidated gluten peptides. We found that AnP2 was efficient down to a 1:64 protease:substrate ratio (w:w). When AnP2 was tested in assays using seven gluten-reactive T cell lines from individual CD patients (three adults and four children), the response to gluten was diminished in all cases. Our study indicates a therapeutic benefit of AnP2 to CD patients.

  6. Anti-Angiogenic Action of Neutral Endopeptidase

    Science.gov (United States)

    2007-11-01

    kidney , intestine, endometrium, adrenal glands, and lung. This enzyme cleaves peptide bonds on the amino side of hydrophobic amino acids and inactivates...Kintscher U et al. Leptin induces endothelial cell migration through Akt, which is inhibited by PPARgamma-ligands. Hypertension 2002; 40: 748–754

  7. Trichomonas vaginalis Cysteine Proteinases: Iron Response in Gene Expression and Proteolytic Activity.

    Science.gov (United States)

    Arroyo, Rossana; Cárdenas-Guerra, Rosa Elena; Figueroa-Angulo, Elisa Elvira; Puente-Rivera, Jonathan; Zamudio-Prieto, Olga; Ortega-López, Jaime

    2015-01-01

    We focus on the iron response of Trichomonas vaginalis to gene family products such as the cysteine proteinases (CPs) involved in virulence properties. In particular, we examined the effect of iron on the gene expression regulation and function of cathepsin L-like and asparaginyl endopeptidase-like CPs as virulence factors. We addressed some important aspects about CPs genomic organization and we offer possible explanations to the fact that only few members of this large gene family are expressed at the RNA and protein levels and the way to control their proteolytic activity. We also summarized all known iron regulations of CPs at transcriptional, posttranscriptional, and posttranslational levels along with new insights into the possible epigenetic and miRNA processes.

  8. Sweet potato cysteine proteases SPAE and SPCP2 participate in sporamin degradation during storage root sprouting.

    Science.gov (United States)

    Chen, Hsien-Jung; Liang, Shu-Hao; Huang, Guan-Jhong; Lin, Yaw-Huei

    2015-08-15

    Sweet potato sporamins are trypsin inhibitors and exhibit strong resistance to digestion by pepsin, trypsin and chymotrypsin. In addition, they constitute the major storage proteins in the sweet potato and, after degradation, provide nitrogen as a nutrient for seedling regrowth in sprouting storage roots. In this report, four cysteine proteases-one asparaginyl endopeptidase (SPAE), two papain-like cysteine proteases (SPCP1 and SPCP2), and one granulin-containing cysteine protease (SPCP3)-were studied to determine their association with sporamin degradation in sprouting storage roots. Sporamin degradation became significant in the flesh of storage roots starting from week 4 after sprouting and this correlated with expression levels of SPAE and SPCP2, but not of SPCP1 and SPCP3. In the outer flesh near the skin, sporamin degradation was more evident and occurred earlier than in the inner flesh of storage roots. Degradation of sporamins in the outer flesh was inversely correlated with the distance of the storage root from the sprout. Exogenous application of SPAE and SPCP2, but not SPCP3, fusion proteins to crude extracts of the outer flesh (i.e., extracted from a depth of 0.3cm and within 2cm of one-week-old sprouts) promoted in vitro sporamin degradation in a dose-dependent manner. Pre-treatment of SPAE and SPCP2 fusion proteins at 95°C for 5min prior to their application to the crude extracts reduced sporamin degradation. These data show that sweet potato asparaginyl endopeptidase SPAE and papain-like cysteine protease SPCP2 participate in sporamin degradation during storage root sprouting.

  9. Serotype-Selective, Small-Molecule Inhibitors of the Zinc Endopeptidase of Botulinum Neurotoxin Serotype A

    Science.gov (United States)

    2006-01-01

    this biphasic mixture, 1.5 mL (1.5 mmol) of 1.0 N HCl was added. The phases were separated and the aque - ous phase was washed with 40 mL EtOAc. The...Kessler, K. R.; Benecke, R. Neurotoxicology 1997 , 18, 761. 3. Springen,K.; Raymond, J.; Skipp, C.; Scelfo, J.; Smalley, S. Newsweek 2002, 50. 4. Singh, B. R...Tetrahedron 2001, 57, 9951. 47. Schmidt, J. J.; Bostian, K. A. J. Protein Chem. 1997 , 16, 19. 48. Schmidt, J. J.; Stafford, R. G. Appl. Environ

  10. Targeting prolyl endopeptidase with valproic acid as a potential modulator of neutrophilic inflammation.

    Directory of Open Access Journals (Sweden)

    Mojtaba Abdul Roda

    Full Text Available A novel neutrophil chemoattractant derived from collagen, proline-glycine-proline (PGP, has been recently characterized in chronic obstructive pulmonary disease (COPD. This peptide is derived via the proteolytic activity of matrix metalloproteases (MMP's-8/9 and PE, enzymes produced by neutrophils and present in COPD serum and sputum. Valproic acid (VPA is an inhibitor of PE and could possibly have an effect on the severity of chronic inflammation. Here the interaction site of VPA to PE and the resulting effect on the secondary structure of PE is investigated. Also, the potential inhibition of PGP-generation by VPA was examined in vitro and in vivo to improve our understanding of the biological role of VPA. UV-visible, fluorescence spectroscopy, CD and NMR were used to determine kinetic information and structural interactions between VPA and PE. In vitro, PGP generation was significantly inhibited by VPA. In vivo, VPA significantly reduced cigarette-smoke induced neutrophil influx. Investigating the molecular interaction between VPA and PE showed that VPA modified the secondary structure of PE, making substrate binding at the catalytic side of PE impossible. Revealing the molecular interaction VPA to PE may lead to a better understanding of the involvement of PE and PGP in inflammatory conditions. In addition, the model of VPA interaction with PE suggests that PE inhibitors have a great potential to serve as therapeutics in inflammatory disorders.

  11. Targeting prolyl endopeptidase with valproic acid as a potential modulator of neutrophilic inflammation

    NARCIS (Netherlands)

    Abdul Roda, Mojtaba; Sadik, Mariam; Gaggar, Amit; Hardison, Matthew T; Jablonsky, Michael J; Braber, Saskia; Blalock, James Edwin; Redegeld, Frank A; Folkerts, Gert; Jackson, Patricia L

    2014-01-01

    A novel neutrophil chemoattractant derived from collagen, proline-glycine-proline (PGP), has been recently characterized in chronic obstructive pulmonary disease (COPD). This peptide is derived via the proteolytic activity of matrix metalloproteases (MMP's)-8/9 and PE, enzymes produced by neutrophil

  12. CD10 (Neutral Endopeptidase) Expression in Myoepithelial Cells of Salivary Neoplasms.

    Science.gov (United States)

    Neves, Catarina de Oliveira; Soares, Andresa Borges; Costa, Ana Flávia; de Araujo, Vera Cavalcanti; Furuse, Cristiane; Juliano, Priscila Bianchi; Altemani, Albina

    2010-03-01

    CD10 is a cell surface peptidase expressed in a wide variety of normal and neoplastic tissues, including breast myoepithelial cells. In salivary glands, expression of CD10 has only been used to identify neoplastic myoepithelial cells of pleomorphic adenomas and myoepithelial carcinomas. However, its accuracy in other salivary tumors with myoepithelial component has yet to be analyzed. We examined 72 salivary tumors with myoepithelial differentiation using immunohistochemical technique to detect CD10. In salivary glands, CD10 expression was not detected in myoepithelial cells. Only fibrocytes within the intralobular stroma were CD10 positive. In neoplastic myoepithelial cells, CD10 expression was found in 25.71% of benign and 32.43% of malignant neoplasms. When the different groups of tumors were compared, epithelial-myoepithelial carcinomas (EMEC) showed a stark contrast with the others (83.3% of cases with CD10 expression). Surprisingly, adenoid cystic carcinomas and basal cell adenomas were negative in 100% of the cases. Myoepitheliomas, pleomorphic adenomas, and myoepithelial carcinomas were positive in 27.7%, 30.0%, and 40% of the cases, respectively. In conclusion, salivary neoplastic myoepithelial cells gain CD10 expression in relation to their normal counterparts. However, the gain of this protein is not a sensitive marker for detecting myoepithelial cells in the majority of the tumors, except for EMEC. The high expression of CD10 by this carcinoma can be a valuable tool to separate EMEC from the tubular variant of adenoid cystic carcinomas in small incisional biopsies, where the precise diagnosis may be impossible.

  13. High pressure treatment of brine enhanced pork affects endopeptidase activity, protein solubility, and peptide formation

    DEFF Research Database (Denmark)

    Grossi, Alberto Blak; Gkarane, Vasiliki; Otte, Jeanette Anita Held;

    2012-01-01

    at 600 MPa following storage at 2 °C for up to 8 weeks. In this report a novel protocol for SDS gelatin zymography was established, and an increase of cathepsin B and L activity after HP treatment was shown followed by a decrease during storage. No calpain activity was detected following HP treatment. HP...

  14. Aeromonas sobria serine protease (ASP): a subtilisin family endopeptidase with multiple virulence activities.

    Science.gov (United States)

    Imamura, Takahisa; Murakami, Yoji; Nitta, Hidetoshi

    2017-09-26

    Aeromonas sobria serine protease (ASP) is secreted from Aeromonas sobria, a pathogen causing gastroenteritis and sepsis. ASP resembles Saccharomyces cerevisiae Kex2, a member of the subtilisin family, and preferentially cleaves peptide bonds at the C-terminal side of paired basic amino acid residues; also accepting unpaired arginine at the P1 site. Unlike Kex2, however, ASP lacks an intramolecular chaperone N-terminal propeptide, instead utilizes the external chaperone ORF2 for proper folding, therefore, ASP and its homologues constitute a new subfamily in the subtilisin family. Through activation of the kallikrein/kinin system, ASP induces vascular leakage, and presumably causes edema and septic shock. ASP accelerates plasma clotting by α-thrombin generation from prothrombin, whereas it impairs plasma clottability by fibrinogen degradation, together bringing about blood coagulation disorder that occurs in disseminated intravascular coagulation, a major complication of sepsis. From complement C5 ASP liberates C5a that induces neutrophil recruitment and superoxide release, and mast cell degranulation, which are associated with pus formation, tissue injury and diarrhea, respectively. Nicked two-chain ASP also secreted from A. sobria is more resistant to inactivation by α2-macroglobulin than single-chain ASP, thereby raising virulence activities. Thus, ASP is a potent virulence factor and may participate in the pathogenesis of A. sobria infection.

  15. Highly sensitive and adaptable fluorescence-quenched pair discloses the substrate specificity profiles in diverse protease families

    Science.gov (United States)

    Poreba, Marcin; Szalek, Aleksandra; Rut, Wioletta; Kasperkiewicz, Paulina; Rutkowska-Wlodarczyk, Izabela; Snipas, Scott J.; Itoh, Yoshifumi; Turk, Dusan; Turk, Boris; Overall, Christopher M.; Kaczmarek, Leszek; Salvesen, Guy S.; Drag, Marcin

    2017-01-01

    Internally quenched fluorescent (IQF) peptide substrates originating from FRET (Förster Resonance Energy Transfer) are powerful tool for examining the activity and specificity of proteases, and a variety of donor/acceptor pairs are extensively used to design individual substrates and combinatorial libraries. We developed a highly sensitive and adaptable donor/acceptor pair that can be used to investigate the substrate specificity of cysteine proteases, serine proteases and metalloproteinases. This novel pair comprises 7-amino-4-carbamoylmethylcoumarin (ACC) as the fluorophore and 2,4-dinitrophenyl-lysine (Lys(DNP)) as the quencher. Using caspase-3, caspase-7, caspase-8, neutrophil elastase, legumain, and two matrix metalloproteinases (MMP2 and MMP9), we demonstrated that substrates containing ACC/Lys(DNP) exhibit 7 to 10 times higher sensitivity than conventional 7-methoxy-coumarin-4-yl acetic acid (MCA)/Lys(DNP) substrates; thus, substantially lower amounts of substrate and enzyme can be used for each assay. We therefore propose that the ACC/Lys(DNP) pair can be considered a novel and sensitive scaffold for designing substrates for any group of endopeptidases. We further demonstrate that IQF substrates containing unnatural amino acids can be used to investigate protease activities/specificities for peptides containing post-translationally modified amino acids. Finally, we used IQF substrates to re-investigate the P1-Asp characteristic of caspases, thus demonstrating that some human caspases can also hydrolyze substrates after glutamic acid. PMID:28230157

  16. Expression and characterization of a His-tagged 11S seed globulin from Amaranthus hypochondriacus in Escherichia coli.

    Science.gov (United States)

    Medina-Godoy, Sergio; Nielsen, Niels C; Paredes-López, Octavio

    2004-01-01

    DNA encoding a His-tagged 11S globulin from Amaranthus hypochondriacus (amarantin) was successfully expressed in Escherichia coli strains BL21 (DE3) and Origami (DE3). The two strains produced different accumulation patterns. Whereas most of the proamarantin expressed in BL21 (DE3) was localized in inclusion bodies, that produced in Origami (DE3) was soluble (76 mg/L). Sucrose density gradient ultracentrifugation analysis of the expressed soluble proamarantin revealed that the protein was assembled into trimers. Treatment of proamarantin trimers in vitro using purified asparaginyl endopeptidase resulted in the appearance of peptides of the sizes expected for acidic and basic chains. Because the proamarantin assembles into trimers with the expected sedimentation characteristics and is cleaved into acidic and basic chains rather than being degraded, the results suggest that the protein folding occurring in E. coli is similar to that taking place in seeds. The His-tagged proamarantin was purified in a single step by immobilized metal affinity chromatography with a final yield of 48 mg/L. The overexpression of proamarantin in E. coli, together with the one-step purification will facilitate further investigation of this storage protein through site-directed mutagenesis.

  17. Two secreted cystatins of the soft tick Ornithodoros moubata: differential expression pattern and inhibitory specificity.

    Science.gov (United States)

    Grunclová, Lenka; Horn, Martin; Vancová, Marie; Sojka, Daniel; Franta, Zdenek; Mares, Michael; Kopácek, Petr

    2006-12-01

    Two genes coding for cysteine peptidase inhibitors of the cystatin family (Om-cystatin 1 and 2) were isolated from a gut-specific cDNA library of the soft tick Ornithodoros moubata. Both cystatins were clearly down-regulated after a blood meal. Om-cystatin 1 is mainly expressed in the tick gut, while Om-cystatin 2 mRNA was also found in other tick tissues. Authentic Om-cystatin 2 was significantly more abundant than Om-cystatin 1 in the gut contents of fasting ticks and was associated with hemosome-derived residual bodies accumulated in the gut lumen. Om-cystatin 2 was also expressed by type 2 secretory cells in the salivary glands of unfed ticks. The inhibitory specificity of recombinant Om-cystatins 1 and 2 was tested with mammalian cysteine peptidases, as well as endogenous cysteine peptidases present in the tick gut. Both cystatins efficiently inhibited papain-like peptidases, including cathepsin B and H, but differed significantly in their affinity towards cathepsin C and failed to block asparaginyl endopeptidase. Our results suggest that the secreted cystatin isoinhibitors are involved in the regulation of multiple proteolytic targets in the tick digestive system and tick-host interaction.

  18. Heparin modulates the endopeptidase activity of Leishmania mexicana cysteine protease cathepsin L-Like rCPB2.8.

    Directory of Open Access Journals (Sweden)

    Wagner A S Judice

    Full Text Available Cysteine protease B is considered crucial for the survival and infectivity of the Leishmania in its human host. Several microorganism pathogens bind to the heparin-like glycosaminoglycans chains of proteoglycans at host-cell surface to promote their attachment and internalization. Here, we have investigated the influence of heparin upon Leishmania mexicana cysteine protease rCPB2.8 activity.THE DATA ANALYSIS REVEALED THAT THE PRESENCE OF HEPARIN AFFECTS ALL STEPS OF THE ENZYME REACTION: (i it decreases 3.5-fold the k 1 and 4.0-fold the k -1, (ii it affects the acyl-enzyme accumulation with pronounced decrease in k 2 (2.7-fold, and also decrease in k 3 (3.5-fold. The large values of ΔG  =  12 kJ/mol for the association and dissociation steps indicate substantial structural strains linked to the formation/dissociation of the ES complex in the presence of heparin, which underscore a conformational change that prevents the diffusion of substrate in the rCPB2.8 active site. Binding to heparin also significantly decreases the α-helix content of the rCPB2.8 and perturbs the intrinsic fluorescence emission of the enzyme. The data strongly suggest that heparin is altering the ionization of catalytic (Cys(25-S(-/(His(163-Im(+ H ion pair of the rCPB2.8. Moreover, the interaction of heparin with the N-terminal pro-region of rCPB2.8 significantly decreased its inhibitory activity against the mature enzyme.Taken together, depending on their concentration, heparin-like glycosaminoglycans can either stimulate or antagonize the activity of cysteine protease B enzymes during parasite infection, suggesting that this glycoconjugate can anchor parasite cysteine protease at host cell surface.

  19. Neutral endopeptidase 24.11 is important for the degradation of both endogenous and exogenous glucagon in anesthetized pigs

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Klarskov, Letty; Olesen, Mette;

    2004-01-01

    , a selective NEP inhibitor, on plasma levels of endogenous and exogenous glucagon was examined in anesthetized pigs. Candoxatril increased endogenous glucagon concentrations, from 6.3 +/- 2.5 to 20.7 +/- 6.3 pmol/l [COOH-terminal (C)-RIA, P

  20. Changes in midgut endopeptidase activity of Spodoptera frugiperda (Lepidoptera: Noctuidae) are responsible for adaptation to soybean proteinase inhibitors.

    Science.gov (United States)

    Paulillo, L C; Lopes, A R; Cristofoletti, P T; Parra, J R; Terra, W R; Silva-Filho, M C

    2000-06-01

    The development of transgenic maize plants expressing soybean proteinase inhibitors could reduce the economic damage of one of the major maize pests in Brazil, the fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797). We examined the influence of soybean proteinase inhibitors on digestive enzyme properties and development of S. frugiperda larvae. The inhibition of trypsin and chymotrypsin activities in vitro by soybean proteinase inhibitors suggested that either Kunitz (SBTI) or Bowman-Birk (SBBI) would have a potential antimetabolic effect when ingested by insect larvae. However, chronic ingestion of semipurified soybean inhibitors did not result in a significant reduction of growth and development of fall armyworm. Therefore, digestive serine proteinase activities (trypsin and chymotrypsin) of fall armyworm larvae were characterized. The results suggest that S. frugiperda was able to physiologically adapt to dietary proteinase inhibitors by altering the complement of proteolytic enzymes in the insect midguts.

  1. Bis-imidazoles as Molecular Probes for Peripheral Sites of the Zinc Endopeptidase of Botulinum Neurotoxin Serotype A

    Science.gov (United States)

    2006-02-02

    favorably with the carboxylate of Glu54 (Fig. 2). The computa- tionally predicted ionic interaction of 2e with Glu54 is supported by our measured pKa...acidic pKa value of 3h impairs the ionic interaction of 3h with Glu54 thus disabling the two-site binding of 3h. Like imidazole alone, 3h and its

  2. Silencing of cystatin M in metastatic oral cancer cell line MDA-686Ln by siRNA increases cysteine proteinases and legumain activities, cell proliferation and in vitro invasion.

    NARCIS (Netherlands)

    Vigneswaran, N.; Wu, J.; Nagaraj, N.; James, R.; Zeeuwen, P.L.J.M.; Zacharias, W.

    2006-01-01

    Cystatins are inhibitors of lysosomal cysteine proteinases. Cystatin M demonstrates more diverse tissue distribution, target specificity and biological function than other cystatins from the same family. We utilized small interference RNAs (siRNA) to silence cystatin M gene expression in a metastati

  3. The T box regulatory element controlling expression of the class I lysyl-tRNA synthetase of Bacillus cereus strain 14579 is functional and can be partially induced by reduced charging of asparaginyl-tRNAAsn

    LENUS (Irish Health Repository)

    Foy, Niall

    2010-07-22

    Abstract Background Lysyl-tRNA synthetase (LysRS) is unique within the aminoacyl-tRNA synthetase family in that both class I (LysRS1) and class II (LysRS2) enzymes exist. LysRS1 enzymes are found in Archaebacteria and some eubacteria while all other organisms have LysRS2 enzymes. All sequenced strains of Bacillus cereus (except AH820) and Bacillus thuringiensis however encode both a class I and a class II LysRS. The lysK gene (encoding LysRS1) of B. cereus strain 14579 has an associated T box element, the first reported instance of potential T box control of LysRS expression. Results A global study of 891 completely sequenced bacterial genomes identified T box elements associated with control of LysRS expression in only four bacterial species: B. cereus, B. thuringiensis, Symbiobacterium thermophilum and Clostridium beijerinckii. Here we investigate the T box element found in the regulatory region of the lysK gene in B. cereus strain 14579. We show that this T box element is functional, responding in a canonical manner to an increased level of uncharged tRNALys but, unusually, also responding to an increased level of uncharged tRNAAsn. We also show that B. subtilis strains with T box regulated expression of the endogenous lysS or the heterologous lysK genes are viable. Conclusions The T box element controlling lysK (encoding LysRS1) expression in B. cereus strain 14579 is functional, but unusually responds to depletion of charged tRNALys and tRNAAsn. This may have the advantage of making LysRS1 expression responsive to a wider range of nutritional stresses. The viability of B. subtilis strains with a single LysRS1 or LysRS2, whose expression is controlled by this T box element, makes the rarity of the occurrence of such control of LysRS expression puzzling.

  4. The T box regulatory element controlling expression of the class I lysyl-tRNA synthetase of Bacillus cereus strain 14579 is functional and can be partially induced by reduced charging of asparaginyl-tRNAAsn

    Directory of Open Access Journals (Sweden)

    Conant Gavin C

    2010-07-01

    Full Text Available Abstract Background Lysyl-tRNA synthetase (LysRS is unique within the aminoacyl-tRNA synthetase family in that both class I (LysRS1 and class II (LysRS2 enzymes exist. LysRS1 enzymes are found in Archaebacteria and some eubacteria while all other organisms have LysRS2 enzymes. All sequenced strains of Bacillus cereus (except AH820 and Bacillus thuringiensis however encode both a class I and a class II LysRS. The lysK gene (encoding LysRS1 of B. cereus strain 14579 has an associated T box element, the first reported instance of potential T box control of LysRS expression. Results A global study of 891 completely sequenced bacterial genomes identified T box elements associated with control of LysRS expression in only four bacterial species: B. cereus, B. thuringiensis, Symbiobacterium thermophilum and Clostridium beijerinckii. Here we investigate the T box element found in the regulatory region of the lysK gene in B. cereus strain 14579. We show that this T box element is functional, responding in a canonical manner to an increased level of uncharged tRNALys but, unusually, also responding to an increased level of uncharged tRNAAsn. We also show that B. subtilis strains with T box regulated expression of the endogenous lysS or the heterologous lysK genes are viable. Conclusions The T box element controlling lysK (encoding LysRS1 expression in B. cereus strain 14579 is functional, but unusually responds to depletion of charged tRNALys and tRNAAsn. This may have the advantage of making LysRS1 expression responsive to a wider range of nutritional stresses. The viability of B. subtilis strains with a single LysRS1 or LysRS2, whose expression is controlled by this T box element, makes the rarity of the occurrence of such control of LysRS expression puzzling.

  5. Supplementation of Reduced Gluten Barley Diet with Oral Prolyl Endopeptidase Effectively Abrogates Enteropathy-Associated Changes in Gluten-Sensitive Macaques.

    Science.gov (United States)

    Sestak, Karol; Thwin, Hazel; Dufour, Jason; Liu, David X; Alvarez, Xavier; Laine, David; Clarke, Adam; Doyle, Anthony; Aye, Pyone P; Blanchard, James; Moehs, Charles P

    2016-06-28

    Celiac disease (CD) is an autoimmune disorder that affects approximately three million people in the United States. Furthermore, non-celiac gluten sensitivity (NCGS) affects an estimated additional 6% of the population, e.g., 20 million in the U.S. The only effective treatment of CD and NCGS requires complete removal of gluten sources from the diet. While required adherence to a gluten-free diet (GFD) is extremely difficult to accomplish, efforts to develop additional supportive treatments are needed. To facilitate these efforts, we developed a gluten-sensitive (GS) rhesus macaque model to study the effects of novel therapies. Recently reported results from phase one of this project suggest that partial improvement-but not remission-of gluten-induced disease can be accomplished by 100-fold reduction of dietary gluten, i.e., 200 ppm-by replacement of conventional dietary sources of gluten with a mutant, reduced gluten (RG) barley (lys3a)-derived source. The main focus of this (phase two) study was to determine if the inflammatory effects of the residual gluten in lys3a mutant barley grain could be further reduced by oral supplementation with a prolylendopeptidase (PE). Results reveal that PE supplementation of RG barley diet induces more complete immunological, histopathological and clinical remission than RG barley diet alone. The combined effects of RG barley diet and PE supplementation resulted in a further decrease of inflammatory mediators IFN-γ and TNF secretion by peripheral lymphocytes, as well as decreased plasma anti-gliadin and anti-intestinal tissue transglutaminase (TG2) antibodies, diminished active caspase production in small intestinal mucosa, and eliminated clinical diarrhea-all comparable with a gluten-free diet induced remission. In summary, the beneficial results of a combined RG barley and PE administration in GS macaques may warrant the investigation of similar synergistic approaches.

  6. Expression of Neutral Endopeptidase, Endothelin-1, and Nuclear Factor Kappa B in Prostate Cancer: Interrelations and Associations with Prostate-Specific Antigen Recurrence after Radical Prostatectomy

    Directory of Open Access Journals (Sweden)

    Panagiotis J. Vlachostergios

    2012-01-01

    Conclusions. There seems to be a clinical model of NEP/NPs and NFκB pathways interconnection, with their constituents following inverse patterns of expression in accordance with their biological roles and molecular interrelations.

  7. Potent New Small-Molecule Inhibitor of Botulinum Neurotoxin Serotype A Endopeptidase Developed by Synthesis-Based Computer-Aided Molecular Design

    Science.gov (United States)

    2009-11-01

    an equine product that causes allergic reactions in ,10% of patients [6]. In late 2003, a solution of human antibodies was licensed as ‘‘BabyBIG’’ to...Biol 351: 431–442. 26. Wang Q, Pang Y-P (2007) Accurate reproduction of 161 small-molecule complex crystal structures using the EUDOC program

  8. Supplementation of Reduced Gluten Barley Diet with Oral Prolyl Endopeptidase Effectively Abrogates Enteropathy-Associated Changes in Gluten-Sensitive Macaques

    OpenAIRE

    Karol Sestak; Hazel Thwin; Jason Dufour; Liu, David X.; Xavier Alvarez; David Laine; Adam Clarke; Anthony Doyle; Aye, Pyone P.; James Blanchard; Moehs, Charles P.

    2016-01-01

    Celiac disease (CD) is an autoimmune disorder that affects approximately three million people in the United States. Furthermore, non-celiac gluten sensitivity (NCGS) affects an estimated additional 6% of the population, e.g., 20 million in the U.S. The only effective treatment of CD and NCGS requires complete removal of gluten sources from the diet. While required adherence to a gluten-free diet (GFD) is extremely difficult to accomplish, efforts to develop additional supportive treatments ar...

  9. Supplementation of Reduced Gluten Barley Diet with Oral Prolyl Endopeptidase Effectively Abrogates Enteropathy-Associated Changes in Gluten-Sensitive Macaques

    Directory of Open Access Journals (Sweden)

    Karol Sestak

    2016-06-01

    Full Text Available Celiac disease (CD is an autoimmune disorder that affects approximately three million people in the United States. Furthermore, non-celiac gluten sensitivity (NCGS affects an estimated additional 6% of the population, e.g., 20 million in the U.S. The only effective treatment of CD and NCGS requires complete removal of gluten sources from the diet. While required adherence to a gluten-free diet (GFD is extremely difficult to accomplish, efforts to develop additional supportive treatments are needed. To facilitate these efforts, we developed a gluten-sensitive (GS rhesus macaque model to study the effects of novel therapies. Recently reported results from phase one of this project suggest that partial improvement—but not remission—of gluten-induced disease can be accomplished by 100-fold reduction of dietary gluten, i.e., 200 ppm—by replacement of conventional dietary sources of gluten with a mutant, reduced gluten (RG barley (lys3a-derived source. The main focus of this (phase two study was to determine if the inflammatory effects of the residual gluten in lys3a mutant barley grain could be further reduced by oral supplementation with a prolylendopeptidase (PE. Results reveal that PE supplementation of RG barley diet induces more complete immunological, histopathological and clinical remission than RG barley diet alone. The combined effects of RG barley diet and PE supplementation resulted in a further decrease of inflammatory mediators IFN-γ and TNF secretion by peripheral lymphocytes, as well as decreased plasma anti-gliadin and anti-intestinal tissue transglutaminase (TG2 antibodies, diminished active caspase production in small intestinal mucosa, and eliminated clinical diarrhea—all comparable with a gluten-free diet induced remission. In summary, the beneficial results of a combined RG barley and PE administration in GS macaques may warrant the investigation of similar synergistic approaches.

  10. Characterisation of the active site of a newly-discovered and potentially significant post-proline cleaving endopeptidase called ZIP using LC-MS

    OpenAIRE

    McMahon, Gillian; Collins, Patrick; O'Connor, Brendan

    2003-01-01

    There are enzymes that specifically recognise the amino acid proline within peptides and proteins that are called post-proline cleaving enzymes. Many of them are implicated in neurodegenerative disorders and psychiatric diseases. ZIP is a newly-discovered one of these peptidases. In this work, it has been purified from bovine serum and subjected to various analytical studies in order to characterise it. A series of reactions between synthesised peptides and ZIP were carried out in order to el...

  11. Neutral endopeptidase 24.11 and dipeptidyl peptidase IV are both mediators of the degradation of glucagon-like peptide 1 in the anaesthetised pig

    DEFF Research Database (Denmark)

    Plamboeck, A; Holst, Jens Juul; Carr, R D;

    2005-01-01

    glucose were unaffected by candoxatril, but glucose tolerance was improved (DeltaAUC(min 27-87) 118+/-5 to 74+/-14 min.mmol.l(-1); glucose elimination rate [k] 6.6+/-0.5 to 8.6+/-0.5%; pvaline pyrrolidide (a DPP-IV inhibitor), changes in C-terminal GLP-1...... pharmacokinetics mirrored those seen when candoxatril alone was administered (t(1/2) 2.7+/-0.3 and 7.7+/-0.8 min; MCR 17.3+/-2.6 and 6.5+/-0.8 ml.kg(-1).min(-1) for valine pyrrolidide without and with candoxatril, respectively). However, intact GLP-1 pharmacokinetics were improved (t(1/2) 2.8+/-0.3 and 7...

  12. Supplementation of Reduced Gluten Barley Diet with Oral Prolyl Endopeptidase Effectively Abrogates Enteropathy-Associated Changes in Gluten-Sensitive Macaques

    Science.gov (United States)

    Sestak, Karol; Thwin, Hazel; Dufour, Jason; Liu, David X.; Alvarez, Xavier; Laine, David; Clarke, Adam; Doyle, Anthony; Aye, Pyone P.; Blanchard, James; Moehs, Charles P.

    2016-01-01

    Celiac disease (CD) is an autoimmune disorder that affects approximately three million people in the United States. Furthermore, non-celiac gluten sensitivity (NCGS) affects an estimated additional 6% of the population, e.g., 20 million in the U.S. The only effective treatment of CD and NCGS requires complete removal of gluten sources from the diet. While required adherence to a gluten-free diet (GFD) is extremely difficult to accomplish, efforts to develop additional supportive treatments are needed. To facilitate these efforts, we developed a gluten-sensitive (GS) rhesus macaque model to study the effects of novel therapies. Recently reported results from phase one of this project suggest that partial improvement—but not remission—of gluten-induced disease can be accomplished by 100-fold reduction of dietary gluten, i.e., 200 ppm—by replacement of conventional dietary sources of gluten with a mutant, reduced gluten (RG) barley (lys3a)-derived source. The main focus of this (phase two) study was to determine if the inflammatory effects of the residual gluten in lys3a mutant barley grain could be further reduced by oral supplementation with a prolylendopeptidase (PE). Results reveal that PE supplementation of RG barley diet induces more complete immunological, histopathological and clinical remission than RG barley diet alone. The combined effects of RG barley diet and PE supplementation resulted in a further decrease of inflammatory mediators IFN-γ and TNF secretion by peripheral lymphocytes, as well as decreased plasma anti-gliadin and anti-intestinal tissue transglutaminase (TG2) antibodies, diminished active caspase production in small intestinal mucosa, and eliminated clinical diarrhea—all comparable with a gluten-free diet induced remission. In summary, the beneficial results of a combined RG barley and PE administration in GS macaques may warrant the investigation of similar synergistic approaches. PMID:27367722

  13. Localization and expression of the Bacillus subtilis DL-endopeptidase LytF are influenced by mutations in LTA synthases and glycolipid anchor synthetic enzymes.

    Science.gov (United States)

    Kiriyama, Yuuka; Yazawa, Kazuya; Tanaka, Tatsuhito; Yoshikawa, Ritsuko; Yamane, Hisaya; Hashimoto, Masayuki; Sekiguchi, Junichi; Yamamoto, Hiroki

    2014-12-01

    Bacillus subtilis LytF plays a principal role in cell separation through its localization at the septa and poles on the vegetative cell surface. In this study, we found that a mutation in a major lipoteichoic acid (LTA) synthase gene--ltaS--results in a considerable reduction in the σ(D)-dependent transcription of lytF. The lytF transcription was also reduced in mutants that affected glycolipid anchor biosynthesis. Immunofluorescence microscopy revealed that both the numbers of cells expressing LytF and the LytF foci in these mutants were decreased. In addition, the transcriptional activity of lytF was almost abolished in the double (ltaS yfnI), triple (ltaS yfnI yqgS), and quadruple (ltaS yfnI yqgS yvgJ) mutants during vegetative growth. Cell separation defects in these mutants were partially restored with artificial expression of LytF. Interestingly, when lytF transcription was induced in the ltaS single or multiple mutants, LytF was localized not only at the septum, but also along the sidewall. The amounts of LytF bound to cell wall in the single (ltaS) and double (ltaS yfnI) mutants gradually increased as compared with that in the WT strain, and those in the triple (ltaS yfnI yqgS) and quadruple mutants were almost similar to that in the double mutant. Moreover, reduction of the lytF transcription and chained cell morphology in the ltaS mutant were completely restored with artificial induction of the yqgS gene. These results strongly suggest that LTA influences the temporal, σ(D)-dependent transcription of lytF and is an additional inhibitory component to the vegetative cell separation enzyme LytF.

  14. 7,8-Dihydroxyflavone Ameliorates Cognitive Impairment by Inhibiting Expression of Tau Pathology in ApoE-Knockout Mice

    Directory of Open Access Journals (Sweden)

    Yang Tan

    2016-11-01

    Full Text Available 7,8-Dihydroxyflavone (7,8-DHF, a tyrosine kinase B (TrkB agonist that mimics the neuroprotective properties of brain-derived neurotrophic factor, which can not efficiently deliver into the brain, has been reported to be useful in ameliorating cognitive impairment in many diseases. Researches have indicated that apolipoprotein E-knockout (ApoE-KO mouse was associated with cognitive alteration via various mechanisms. Our present study investigated the possible mechanisms of cognitive impairment of ApoE-KO mouse fed with western type diet and the protective effects of 7,8-DHF in improving spatial learning and memory in ApoE-KO mouse. 5-weeks-old ApoE-KO mice and C57BL/6 mice were chronically treated with 7,8-DHF (with a dosage of 5mg/kg or vehicles orally for 25 weeks, and then subjected to Morris water maze at the age of 30 weeks to evaluate the cognitive performances. Afterwards, histology analysis and western blotting were performed. Spatial learning and memory deficits were observed in ApoE-KO mice, which were consistent with higher expression of active-asparaginyl endopeptidase (active-AEP as well as AEP-derived truncated tauN368 compared with normal group. In addition to that, long-term treatment of 7,8-DHF dramatically ameliorated cognitive decline in ApoE-KO mice, accompanied by the activation in phosphorylated protein kinase B (Akt/glycogen synthase kinase-3β (GSK-3β pathway and down-regulated expression of tau S396 and PHF-tau (phosphorylated tau at ser396 and ser404 epitope. These findings suggested that cognitive impairment of ApoE-KO mouse might associate with tau pathology and 7,8-DHF could activate AKT and then phosphorylate its downstream molecule to inhibit expression of abnormal tau, meanwhile, 7,8-DHF could reduce the expression of active-AEP and then inhibit production of truncated tauN368.

  15. SwissProt search result: AK108469 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK108469 002-143-E04 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 2e-15 ...

  16. SwissProt search result: AK109371 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK109371 006-207-E09 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 3e-91 ...

  17. SwissProt search result: AK059528 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK059528 001-029-D05 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 9e-94 ...

  18. SwissProt search result: AK243297 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243297 J100053I01 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 4e-67 ...

  19. SwissProt search result: AK072767 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK072767 J023138P12 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 3e-76 ...

  20. SwissProt search result: AK121500 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK121500 J033022A11 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 3e-47 ...

  1. SwissProt search result: AK100225 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK100225 J023047M19 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-13 ...

  2. SwissProt search result: AK110539 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK110539 002-168-B01 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 4e-70 ...

  3. SwissProt search result: AK061947 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061947 001-042-E05 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 4e-51 ...

  4. SwissProt search result: AK110832 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK110832 002-172-A05 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 3e-44 ...

  5. SwissProt search result: AK241017 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241017 J065054E09 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 3e-42 ...

  6. SwissProt search result: AK101093 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK101093 J033024N03 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-13 ...

  7. SwissProt search result: AK098910 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK098910 J013002H09 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-91 ...

  8. SwissProt search result: AK099358 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK099358 J033044I21 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 3e-91 ...

  9. SwissProt search result: AK111210 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK111210 002-179-A06 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 8e-20 ...

  10. SwissProt search result: AK098908 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK098908 J013002F17 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 4e-51 ...

  11. SwissProt search result: AK072235 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK072235 J023001J24 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-123 ...

  12. SwissProt search result: AK099197 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK099197 J023120K15 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-74 ...

  13. SwissProt search result: AK063422 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK063422 001-115-C06 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 2e-41 ...

  14. SwissProt search result: AK070448 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK070448 J023048F12 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 3e-44 ...

  15. SwissProt search result: AK243212 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243212 J100042M20 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-39 ...

  16. SwissProt search result: AK066748 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK066748 J013074D19 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 5e-56 ...

  17. SwissProt search result: AK111199 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK111199 002-178-E01 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 8e-19 ...

  18. SwissProt search result: AK107749 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK107749 002-132-H07 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 2e-28 ...

  19. SwissProt search result: AK243501 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243501 J100074J05 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 4e-57 ...

  20. SwissProt search result: AK105612 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK105612 001-200-B06 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-123 ...

  1. SwissProt search result: AK106508 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK106508 002-105-G09 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 6e-93 ...

  2. SwissProt search result: AK099308 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK099308 J023144C09 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-123 ...

  3. SwissProt search result: AK108816 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK108816 002-151-E06 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 9e-34 ...

  4. SwissProt search result: AK107506 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK107506 002-129-E06 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 7e-75 ...

  5. SwissProt search result: AK059697 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK059697 001-032-C04 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-13 ...

  6. SwissProt search result: AK071733 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK071733 J023107H18 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-40 ...

  7. SwissProt search result: AK110974 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK110974 002-174-C02 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-52 ...

  8. SwissProt search result: AK062382 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK062382 001-102-B10 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 3e-48 ...

  9. SwissProt search result: AK068459 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK068459 J013151C17 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 3e-13 ...

  10. SwissProt search result: AK104296 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104296 001-008-H03 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-88 ...

  11. SwissProt search result: AK109160 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK109160 002-155-G07 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 2e-59 ...

  12. SwissProt search result: AK071907 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK071907 J013063O07 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 4e-51 ...

  13. SwissProt search result: AK108733 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK108733 002-150-D05 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 9e-54 ...

  14. SwissProt search result: AK071948 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK071948 J013078J21 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 2e-39 ...

  15. SwissProt search result: AK119670 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK119670 002-149-H07 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 4e-51 ...

  16. SwissProt search result: AK064820 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK064820 J013000E23 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 9e-14 ...

  17. SwissProt search result: AK067453 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK067453 J013106H06 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 5e-74 ...

  18. SwissProt search result: AK099269 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK099269 J023020I09 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 3e-51 ...

  19. SwissProt search result: AK070060 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK070060 J023041D01 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 9e-61 ...

  20. SwissProt search result: AK119182 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK119182 001-037-H03 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 9e-94 ...

  1. SwissProt search result: AK106011 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK106011 001-206-B02 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 9e-94 ...

  2. SwissProt search result: AK105881 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK105881 001-204-D02 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-93 ...

  3. SwissProt search result: AK071913 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK071913 J013065M08 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 2e-91 ...

  4. SwissProt search result: AK061729 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061729 001-038-B12 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 4e-34 ...

  5. SwissProt search result: AK061319 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061319 006-302-E09 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 4e-32 ...

  6. SwissProt search result: AK073373 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK073373 J033027D09 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 2e-90 ...

  7. SwissProt search result: AK071091 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK071091 J023079N05 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 2e-61 ...

  8. SwissProt search result: AK240650 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240650 J023084F10 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 2e-26 ...

  9. SwissProt search result: AK071495 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK071495 J023099K03 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) (...Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-116 ...

  10. SwissProt search result: AK109136 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK109136 002-155-E03 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 6e-67 ...

  11. SwissProt search result: AK060534 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK060534 001-021-A12 (P12412) Vignain precursor (EC 3.4.22.-) (Bean endopeptidase) ...(Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] CYSEP_VIGMU 1e-88 ...

  12. THE INFLUENCE OF SILICA GEL AND PROLYL ENDOPEPTIDASE ON NON-BIOLOGICAL STABILITY OF BEER%硅胶、脯氨酰内肽酶处理对啤酒非生物稳定性的影响

    Institute of Scientific and Technical Information of China (English)

    向先长; 周丽娜; 李玉; 路福平

    2008-01-01

    采用SDS-PAGE电泳,对分别经硅胶吸附和脯氨酰内肽酶水解的啤酒后酵液进行蛋白分布研究;通过测定浊度和泡持性研究二者对啤酒非生物稳定性的影响.结果表明经硅胶吸附和脯氨酰内肽酶水解后的蛋白分子量均集中在8ku~14.4ku和35ku~45ku;经处理后的样品浊度明显下降,而泡持性没有显著变化.其中用脯氨酰内肽酶处理时浊度下降更明显.且对啤酒的泡持性影响更小.因此,在啤酒后酵液中添加脯氨酰内肽酶,能够有效的除去啤酒冷混浊蛋白.提高啤酒的非生物稳定性.

  13. Inhibition of hypoxia-inducible factor (HIF) hydroxylases by citric acid cycle intermediates: possible links between cell metabolism and stabilization of HIF

    National Research Council Canada - National Science Library

    Koivunen, Peppi; Hirsilä, Maija; Remes, Anne M; Hassinen, Ilmo E; Kivirikko, Kari I; Myllyharju, Johanna

    ... (HIF-P4Hs) and one HIF asparaginyl hydroxylase (FIH). We have studied possible links between metabolic pathways and HIF hydroxylases by analyzing the abilities of citric acid cycle intermediates to inhibit purified human HIF-P4Hs and FIH...

  14. A Multienzyme Network Functions in Intestinal Protein Digestion by a Platyhelminth Parasite

    National Research Council Canada - National Science Library

    Melaine Delcroix; Mohammed Sajid; Conor R. Caffrey; Kee-C. Lim; Jan Dvořák; Ivy Hsieh; Mahmoud Bahgat; Colette Dissous; James H. McKerrow

    2006-01-01

    .... Utilizing a combination of protease class-specific inhibitors and RNA interference, we deconvoluted such a network of major endopeptidases functioning in invertebrate intestinal protein digestion...

  15. NCBI nr-aa BLAST: CBRC-TSYR-01-0793 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TSYR-01-0793 ref|ZP_01879965.1| penicillin-insensitive murein endopeptidase [Roseo...varius sp. TM1035] gb|EDM31576.1| penicillin-insensitive murein endopeptidase [Roseovarius sp. TM1035] ZP_01879965.1 5.8 29% ...

  16. NCBI nr-aa BLAST: CBRC-DNOV-01-2878 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DNOV-01-2878 ref|YP_680769.1| murein endopeptidase [Roseobacter denitrificans ...OCh 114] gb|ABG30083.1| murein endopeptidase [Roseobacter denitrificans OCh 114] YP_680769.1 1.4 29% ...

  17. A chimeric LysK-lysostaphin fusion enzyme lysing Staphylococcus aureus cells: a study of both kinetics of inactivation and specifics of interaction with anionic polymers

    Science.gov (United States)

    A staphylolytic fusion protein (K-L) was created, harboring three unique lytic activities comprised of the LysK CHAP endopeptidase, and amidase domains, and the lysostaphin glycyl-glycine endopeptidase domain. To assess the potential of possible therapeutic applications, the kinetic behavior of K-L...

  18. Pharmacokinetic and pharmacodynamic properties of SOL1

    DEFF Research Database (Denmark)

    Nelissen, J; Lemkens, P; Sann, H;

    2012-01-01

    The pharmacological profile of the novel putative neutral endopeptidase (NEP) and endothelin converting enzyme (ECE) inhibitor SOL1 was examined.......The pharmacological profile of the novel putative neutral endopeptidase (NEP) and endothelin converting enzyme (ECE) inhibitor SOL1 was examined....

  19. UniProt search blastx result: AK289220 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK289220 J100065H20 P12412|CYSEP_VIGMU Vignain precursor (EC 3.4.22.-) (Bean endope...ptidase) (Cysteine proteinase) (Sulfhydryl-endopeptidase) (SH-EP) [Contains: Vignain-1; Vignain-2] - Vigna mungo (Rice bean) (Black gram) 3.00E-64 ...

  20. SwissProt search result: AK242832 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242832 J090067L13 (Q8BGE6) Cysteine protease APG4B (EC 3.4.22.-) (Autophagy 4 homolog B) (Autop...hagin-1) (Autophagy-related cysteine endopeptidase 1) (AUT-like 1 cysteine endopeptidase) APG4B_MOUSE 2e-49 ...

  1. SwissProt search result: AK242832 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242832 J090067L13 (Q96DT6) Cysteine protease APG4C (EC 3.4.22.-) (Autophagy 4 homolog C) (Autop...hagin-3) (Autophagy-related cysteine endopeptidase 3) (AUT-like 3 cysteine endopeptidase) APG4C_HUMAN 2e-37 ...

  2. SwissProt search result: AK110731 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK110731 002-170-E10 (Q811C2) Cysteine protease APG4C (EC 3.4.22.-) (Autophagy 4 homolog C) (Autop...hagin-3) (Autophagy-related cysteine endopeptidase 3) (AUT-like 3 cysteine endopeptidase) APG4C_MOUSE 6e-27 ...

  3. NCBI nr-aa BLAST: CBRC-OPRI-01-1475 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-OPRI-01-1475 ref|ZP_02151543.1| membrane endopeptidase, M50 family protein [Ocean...ibulbus indolifex HEL-45] gb|EDQ05410.1| membrane endopeptidase, M50 family protein [Oceanibulbus indolifex HEL-45] ZP_02151543.1 0.43 28% ...

  4. SwissProt search result: AK110731 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK110731 002-170-E10 (Q8WYN0) Cysteine protease APG4A (EC 3.4.22.-) (Autophagy 4 homolog A) (hAPG4A) (Auto...phagin-2) (Autophagy-related cysteine endopeptidase 2) (AUT-like 2 cysteine endopeptidase) APG4A_HUMAN 4e-36 ...

  5. SwissProt search result: AK242832 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242832 J090067L13 (Q8BGV9) Cysteine protease APG4D (EC 3.4.22.-) (Autophagy 4 homolog D) (Auto...phagin-4) (Autophagy-related cysteine endopeptidase 4) (AUT-like 4 cysteine endopeptidase) APG4D_MOUSE 2e-39 ...

  6. SwissProt search result: AK069012 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK069012 J023002M16 (Q8BGE6) Cysteine protease APG4B (EC 3.4.22.-) (Autophagy 4 homolog B) (Auto...phagin-1) (Autophagy-related cysteine endopeptidase 1) (AUT-like 1 cysteine endopeptidase) APG4B_MOUSE 1e-49 ...

  7. SwissProt search result: AK110731 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK110731 002-170-E10 (Q8BGV9) Cysteine protease APG4D (EC 3.4.22.-) (Autophagy 4 homolog D) (Auto...phagin-4) (Autophagy-related cysteine endopeptidase 4) (AUT-like 4 cysteine endopeptidase) APG4D_MOUSE 7e-33 ...

  8. Molecular physiology of digestion in arachnida: functional and comparative-evolutionary approaches.

    OpenAIRE

    Felipe Jun Fuzita

    2014-01-01

    Spiders and scorpions are efficient predators arachnid (PA) consuming preys larger than themselves. Few studies reported, molecularly, the digestion in PA. This work describes a biochemical, transcriptomic and proteomic analysis of the midgut and midgut glands (MMG) and digestive juice (DJ) from Nephilengys cruentata and Tityus serrulatus MMG. Cathepsin L, B, D and F, legumain, trypsin, astacin, carbohydrases and lipases were identified by these approaches. Peptide isomerase and ctenitoxins, ...

  9. Aminoacyl-tRNA synthesis in Archaea.

    Science.gov (United States)

    Ibba, M; Celic, I; Curnow, A; Kim, H; Pelaschier, J; Tumbula, D; Vothknecht, U; Woese, C; Söll, D

    1997-01-01

    The mechanism of aminoacyl-tRNA synthesis differs substantially between Archaea, Bacteria and Eukarya. Sequencing of archaeal genomes has suggested that the asparaginyl-, cysteinyl-, glutaminyl- and lysyl-tRNA synthetases are absent from a number of organisms in this kingdom. The absence of the asparaginyl- and glutaminyl-tRNA synthetases is in agreement with the observation that Asn-tRNA and Gln-tRNA are synthesized by tRNA-dependent transamidation of Asp-tRNA and Glu-tRNA respectively in the archaeon Haloferax volcanii. Biochemical and genetic studies have now shown that while the cysteinyl- and lysyl-tRNA synthetases are present, the enzymes responsible for these activities are unique to Archaea.

  10. Mass spectrometric peptide analysis of 2DE-separated mouse spinal cord and rat hippocampus proteins suggests an NGxG motif of importance for in vivo deamidation.

    Science.gov (United States)

    Mikkat, Stefan; Kischstein, Timo; Kreutzer, Michael; Glocker, Michael O

    2013-06-01

    Asparagine deamidation is a common nonenzymatic post-translational modification comprising the conversion of asparaginyl residues to aspartyl and isoaspartyl residues, respectively. As a result an additional negative charge is introduced that can affect the tertiary structure as well as the biological activity of a protein. Since deamidation reduces the protein's pI value, differentially deamidated forms of a protein can be separated in 2D gels. We have analyzed a dataset of 430 protein spots from 2D gels that contained mouse spinal cord proteins and estimated that roughly 10% of the spots in a Coomassie-stained gel derive from in vivo deamidation at particular asparaginyl residues. Several of the deamidated protein forms, e.g. tropomodulin-2, V-type proton ATPase subunit B, and protein disulfide-isomerase A3 were also found in 2D gels of proteins extracted from rat hippocampus. All identified deamidation sites contained a glycine residue on the carboxyl side of the asparaginyl residue. Strikingly, a second glycine residue at the +3 position was found in the majority of the deamidated peptides. We propose that the NGxG motif confers exceptional susceptibility to in vivo asparagine deamidation.

  11. Protein damage and repair controlling seed vigor and longevity.

    Science.gov (United States)

    Ogé, Laurent; Broyart, Caroline; Collet, Boris; Godin, Béatrice; Jallet, Denis; Bourdais, Gildas; Job, Dominique; Grappin, Philippe

    2011-01-01

    The formation of abnormal isoaspartyl residues derived from aspartyl or asparaginyl residues is a major source of spontaneous protein misfolding in cells. The repair enzyme protein L: -isoaspartyl methyltransferase (PIMT) counteracts such damage by catalyzing the conversion of abnormal isoaspartyl residues to their normal aspartyl forms. Thus, this enzyme contributes to the survival of many organisms, including plants. Analysis of the accumulation of isoaspartyl-containing proteins and its modulation by the PIMT repair pathway, using germination tests, immunodetection, enzymatic assays, and HPLC analysis, gives new insights in understanding controlling mechanisms of seed longevity and vigor.

  12. Modelling family 2 cystatins and their interaction with papain.

    Science.gov (United States)

    Nandy, Suman Kumar; Bhuyan, Rajabrata; Seal, Alpana

    2013-01-01

    Cystatins are extensively studied cysteine protease inhibitors, found in wide range of organisms with highly conserved structural folds. S-type of cystatins is well known for their abundance in saliva, high selectivity and poorer activity towards host cysteine proteases in comparison to their immediate ancestor cystatin C. Despite more than 90% sequence similarity, the members of this group show highly dissimilar binding affinity towards papain. Cystatin M/E is a potent inhibitor of legumain and papain like cysteine proteases and recognized for its involvement in skin barrier formation and potential role as a tumor suppressor gene. However, the structures of these proteins and their complexes with papain or legumain are still unknown. In the present study, we have employed computational methods to get insight into the interactions between papain and cystatins. Three-dimensional structures of the cystatins are generated by homology modelling, refined with molecular dynamics simulation, validated through numerous web servers and finally complexed with papain using ZDOCK algorithm in Discovery Studio. A high degree of shape complementarity is observed within the complexes, stabilized by numerous hydrogen bonds (HB) and hydrophobic interactions. Using interaction energy, HB and solvent accessible surface area analyses, we have identified a series of key residues that may be involved in papain-cystatin interaction. Differential approaches of cystatins towards papain are also noticed which are possibly responsible for diverse inhibitory activity within the group. These findings will improve our understanding of fundamental inhibitory mechanisms of cystatin and provide clues for further research.

  13. Electrochemical Protease Biosensor Based on Enhanced AC Voltammetry Using Carbon Nanofiber Nanoelectrode Arrays.

    Science.gov (United States)

    Swisher, Luxi Z; Syed, Lateef U; Prior, Allan M; Madiyar, Foram R; Carlson, Kyle R; Nguyen, Thu A; Hua, Duy H; Li, Jun

    2013-02-28

    We report an electrochemical method for measuring the activity of proteases using nanoelectrode arrays (NEAs) fabricated with vertically aligned carbon nanofibers (VACNFs). The VACNFs of ~150 nm in diameter and 3 to 5 μm in length were grown on conductive substrates and encapsulated in SiO2 matrix. After polishing and plasma etching, controlled VACNF tips are exposed to form an embedded VACNF NEA. Two types of tetrapeptides specific to cancer-mediated proteases legumain and cathepsin B are covalently attached to the exposed VACNF tip, with a ferrocene (Fc) moiety linked at the distal end. The redox signal of Fc can be measured with AC voltammetry (ACV) at ~1 kHz frequency on VACNF NEAs, showing distinct properties from macroscopic glassy carbon electrodes due to VACNF's unique interior structure. The enhanced ACV properties enable the kinetic measurements of proteolytic cleavage of the surface-attached tetrapeptides by proteases, further validated with a fluorescence assay. The data can be analyzed with a heterogeneous Michaelis-Menten model, giving "specificity constant" kcat /Km as (4.3 ± 0.8) × 10(4) M(-1)s(-1) for cathepsin B and (1.13 ± 0.38) × 10(4) M(-1)s(-1) for legumain. This method could be developed as portable multiplex electronic techniques for rapid cancer diagnosis and treatment monitoring.

  14. The roles of cysteine proteases and phytocystatins in development and germination of cereal seeds.

    Science.gov (United States)

    Szewińska, Joanna; Simińska, Joanna; Bielawski, Wiesław

    2016-12-01

    Proteolysis is an important process for development and germination of cereal seeds. Among the many types of proteases identified in plants are the cysteine proteases (CPs) of the papain and legumain families, which play a crucial role in hydrolysing storage proteins during seed germination as well as in processing the precursors of these proteins and the inactive forms of other proteases. Moreover, all of the tissues of cereal seeds undergo progressive degradation via programed cell death, which is integral to their growth. In view of the important roles played by proteases, their uncontrolled activity could be harmful to the development of seeds and young seedlings. Thus, the activities of these enzymes are regulated by intracellular inhibitors called phytocystatins (PhyCys). The phytocystatins inhibit the activity of proteases of the papain family, and the presence of an additional motif in their C-termini allows them to also regulate the activity of members of the legumain family. A balance between the levels of cysteine proteases and phytocystatins is necessary for proper cereal seed development, and this is maintained through the antagonistic activities of gibberellins (GAs) and abscisic acid (ABA), which regulate the expression of the corresponding genes. Transcriptional regulation of cysteine proteases and phytocystatins is determined by cis-acting elements located in the promoters of these genes and by the expression of their corresponding transcription factors (TFs) and the interactions between different TFs. Copyright © 2016 Elsevier GmbH. All rights reserved.

  15. Finding of primitive polyamine toxins in the venom of a joro spider, Nephila clavata.

    Science.gov (United States)

    Chiba, T; Akizawa, T; Matsukawa, M; Pan-Hou, H; Yoshioka, M

    1994-09-01

    A series of joro spider toxins, novel polyamines sharing a common moiety of 2,4-dihydroxyphenylacetyl cadaverine, have been identified using various bioassays, such as inhibition of a glutamatergic transmission and insecticidal activity. In this paper, we tried to chemically find still unknown polyamine toxins in the venom of a joro spider, N. clavata, by several analytical methods based on the characteristics of the common moiety. An aqueous extract from 3000 venoms was separated by preparative high performance liquid chromatography (HPLC). The polyamine toxins were detected by monitoring the fluorescence produced in an on-line reaction of o-phthalaldehyde with amino groups and UV absorption of the phenol group. Two compounds in minute quantity were purified and analyzed by gas-liquid chromatography (GC) and HPLC, which we specifically developed for the simultaneous determination of amino acids and polyamines of the toxins. Judging from the constituents of the hydrolysate by GC and HPLC and the molecular weights determined by fast atom bombardment mass spectrometry, the two compounds were estimated to be N-(2,4-dihydroxyphenylacetyl-L-asparaginyl)-N'- (3-aminopropyl-beta-alanyl) cadaverine and N-(4-hydroxyphenylacetyl-L-asparaginyl)-N'-(3-aminopropyl-beta-ala nyl) cadaverine. These compounds were small in content and molecular weight compared with hitherto known toxins. Both were presumed to be biochemically primitive toxins and were named spidamine and joramine, respectively.

  16. MOLECULAR CHARACTERIZATION OF THE ANGIOTENSIN-(1-7) SYSTEM COMPONENTS DURING FOLLICULAR DEVIATION AND EXPRESSION OF DNA DOUBLE-STRANDED REPAIR GENES IN BOVINE EMBRYOS

    OpenAIRE

    Marcos Henrique Barreta

    2012-01-01

    O primeiro estudo caracterizou a expressão do receptor MAS e de enzimas responsáveis pela produção de Ang-(1-7), tais como, enzima conversora de angiotensina 2 (ACE2), endopeptidase neutra (NEP) e prolil endopeptidase (PEP) durante o desenvolvimento folicular. Além disso, a regulação local do sistema Ang-(1-7) foi avaliada após a injeção intrafolicular de fulvestrant (inibidor do receptor de estradiol) no folículo dominante. As vacas foram ovariectomizadas quando o tamanho entr...

  17. Properties of a milk clotting protease isolated from fruits of Bromelia balansae Mez.

    Science.gov (United States)

    Pardo, M F; López, L M; Caffini, N O; Natalucci, C L

    2001-05-01

    Unripe fruit extracts of Bromelia balansae Mez (Bromeliaceae), whose principal endopeptidase is balansain I (isolated for anion exchange chromatography: pI = 5.45, molecular weight = 23192), exhibit a pH profile with a maximum activity around pH 9.0 and are inhibited only by cysteine peptidases inhibitors. The alanine and glutamine derivatives of N-alpha-carbobenzoxy-L-amino acid p-nitrophenyl esters were strongly preferred by the enzyme. Enzymatic hydrolysis of milk and soy proteins yield characteristic patterns at pH 9.0. The N-terminal sequence showed a very high homology (85-90%) with other known Bromeliaceae endopeptidases.

  18. Dicty_cDB: Contig-U16605-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 97 |pid:none) Myzus persicae mRNA for putative c... 155 1e-36 AF410881_1( AF410881 |pid:none) Frankliniella ...ta cysteinyl endopeptidase ... 156 2e-36 AF410883_1( AF410883 |pid:none) Franklin

  19. Molecular Cloning and Sequence of Channel Catfish (Ictalurus punctatus, Rafinesque 1818) Cathepsin S gene

    Science.gov (United States)

    Cathepsin S is a lysosomal cysteine endopeptidase of the papain family. This enzyme digests the invariant chain molecules so that antigenic peptides are able to load on the class II-associated invariant chain peptide of MHC. The complexes can subsequently be presented to the CD4 cell surface. In ...

  20. Molecular Cloning and Sequencing of Channel Catfish, Ictalurus punctatus, Cathepsin H and L cDNA

    Science.gov (United States)

    Cathepsin H and L, a lysosomal cysteine endopeptidase of the papain family, are ubiquitously expressed and involve in antigen processing. In this communication, the channel catfish cathepsin H and L transcripts were sequenced and analyzed. Total RNA from tissues was extracted and cDNA libraries we...

  1. Molecular Cloning, Sequencing and Characterization of Channel Catfish (Ictalurus punctatus, Rafinesque 1818) Cathepsin S Gene

    Science.gov (United States)

    Cathepsin S is a lysosomal cysteine endopeptidase of the papain family. Our preliminary results showed the up-regulation of cathepsin S (CTSS) transcript during the early stage of Edwardsiella ictaluri infection. This prompted us to speculate that the CTSS may play a role in infection. In this re...

  2. Domain Modeling: NP_001035845.1 [SAHG[Archive

    Lifescience Database Archive (English)

    Full Text Available s: Role of Inter-Domain Dynamics in Catalysis and Specificity p1yr2a_ chr2/NP_001035845.1/NP_001035845.1_apo_15-650.pdb psi-blast 0 ... ...NP_001035845.1 chr2 Structural and Mechanistic Analysis of Two Prolyl Endopeptidase

  3. Domain Modeling: NP_006027.2 [SAHG[Archive

    Lifescience Database Archive (English)

    Full Text Available NP_006027.2 chr2 Structural and Mechanistic Analysis of Two Prolyl Endopeptidases: Role of Inter-Domain Dyna...mics in Catalysis and Specificity p1yr2a_ chr2/NP_006027.2/NP_006027.2_apo_44-716.pdb psi-blast 559S,645D,690H 0 ...

  4. SwissProt search result: AK067789 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK067789 J013116D21 (Q8MNZ1) Leishmanolysin precursor (EC 3.4.24.36) (Cell surface protease) (Major surf...ace glycoprotein) (Protein gp63) (Promastigote surface endopeptidase) (Major surface protease) GP63_LEITR 3e-42 ...

  5. SwissProt search result: AK119888 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK119888 002-179-H09 (Q8MNZ1) Leishmanolysin precursor (EC 3.4.24.36) (Cell surface protease) (Major surf...ace glycoprotein) (Protein gp63) (Promastigote surface endopeptidase) (Major surface protease) GP63_LEITR 2e-42 ...

  6. SwissProt search result: AK119888 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK119888 002-179-H09 (P23223) Leishmanolysin precursor (EC 3.4.24.36) (Cell surface protease) (Major surf...ace glycoprotein) (Protein gp63) (Promastigote surface endopeptidase) (Major surface protease) GP63_LEIDO 1e-39 ...

  7. SwissProt search result: AK067789 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK067789 J013116D21 (Q27673) Leishmanolysin precursor (EC 3.4.24.36) (Cell surface protease) (Major surf...ace glycoprotein) (Protein gp63) (Promastigote surface endopeptidase) (Major surface protease) GP63_LEIAM 2e-33 ...

  8. SwissProt search result: AK119888 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK119888 002-179-H09 (Q27673) Leishmanolysin precursor (EC 3.4.24.36) (Cell surface protease) (Major surf...ace glycoprotein) (Protein gp63) (Promastigote surface endopeptidase) (Major surface protease) GP63_LEIAM 1e-33 ...

  9. SwissProt search result: AK119888 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK119888 002-179-H09 (P08148) Leishmanolysin precursor (EC 3.4.24.36) (Cell surface protease) (Major surf...ace glycoprotein) (Protein gp63) (Promastigote surface endopeptidase) (Major surface protease) GP63_LEIMA 3e-37 ...

  10. SwissProt search result: AK099947 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK099947 J013123C23 (Q00689) Leishmanolysin precursor (EC 3.4.24.36) (Cell surface protease) (Major surf...ace glycoprotein) (Protein gp63) (Promastigote surface endopeptidase) (Major surface protease) GP63_LEIGU 1e-35 ...

  11. SwissProt search result: AK067789 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK067789 J013116D21 (P08148) Leishmanolysin precursor (EC 3.4.24.36) (Cell surface protease) (Major surf...ace glycoprotein) (Protein gp63) (Promastigote surface endopeptidase) (Major surface protease) GP63_LEIMA 3e-37 ...

  12. SwissProt search result: AK099947 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK099947 J013123C23 (P43150) Leishmanolysin C1 precursor (EC 3.4.24.36) (Cell surface protease) (Major surf...ace glycoprotein) (Protein gp63) (Promastigote surface endopeptidase) (Major surface protease) GP63_LEIME 4e-42 ...

  13. SwissProt search result: AK099947 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK099947 J013123C23 (P15706) Leishmanolysin precursor (EC 3.4.24.36) (Cell surface protease) (Major surf...ace glycoprotein) (Protein gp63) (Promastigote surface endopeptidase) (Major surface protease) GP63_LEICH 5e-35 ...

  14. Structural and Biochemical Studies of LysM Proteins

    DEFF Research Database (Denmark)

    Wong, Mei Mei Jaslyn Elizabeth

    2016-01-01

    The Lysin Motif (LysM) is a well characterised carbohydrate-binding module that is present, usually as repeated entities, in proteins from all organisms except archaea. The functional significance of the multiplicity of the LysM module was investigated using two homologous NlpC/P60 endopeptidases...

  15. Development of an integrated system for activity-based profiling of matrix metallo-proteases

    NARCIS (Netherlands)

    Freije, Jan Robert

    2006-01-01

    Matrix metallo-proteases constitute a family of extracellular zinc-dependent endopeptidases that are involved in degradation of extracellular matrix (ECM) components and other bioactive non-ECM molecules. A plethora of studies have implicated important roles for MMPs in many diseases (including

  16. PRB1 is required for clipping of the histone H3 N terminal tail in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Yong Xue

    Full Text Available Cathepsin L, a lysosomal protein in mouse embryonic stem cells has been shown to clip the histone H3 N- terminus, an activity associated with gene activity during mouse cell development. Glutamate dehydrogenase (GDH was also identified as histone H3 specific protease in chicken liver, which has been connected to gene expression during aging. In baker's yeast, Saccharomyces cerevisiae, clipping the histone H3 N-terminus has been associated with gene activation in stationary phase but the protease responsible for the yeast histone H3 endopeptidase activity had not been identified. In searching for a yeast histone H3 endopeptidase, we found that yeast vacuolar protein Prb1 is present in the cellular fraction enriched for the H3 N-terminus endopeptidase activity and this endopeptidase activity is lost in the PRB1 deletion mutant (prb1Δ. In addition, like Cathepsin L and GDH, purified Prb1 from yeast cleaves H3 between Lys23 and Ala24 in the N-terminus in vitro as shown by Edman degradation. In conclusion, our data argue that PRB1 is required for clipping of the histone H3 N-terminal tail in Saccharomyces cerevisiae.

  17. PRB1 is required for clipping of the histone H3 N terminal tail in Saccharomyces cerevisiae.

    Science.gov (United States)

    Xue, Yong; Vashisht, Ajay A; Tan, Yuliang; Su, Trent; Wohlschlegel, James A

    2014-01-01

    Cathepsin L, a lysosomal protein in mouse embryonic stem cells has been shown to clip the histone H3 N- terminus, an activity associated with gene activity during mouse cell development. Glutamate dehydrogenase (GDH) was also identified as histone H3 specific protease in chicken liver, which has been connected to gene expression during aging. In baker's yeast, Saccharomyces cerevisiae, clipping the histone H3 N-terminus has been associated with gene activation in stationary phase but the protease responsible for the yeast histone H3 endopeptidase activity had not been identified. In searching for a yeast histone H3 endopeptidase, we found that yeast vacuolar protein Prb1 is present in the cellular fraction enriched for the H3 N-terminus endopeptidase activity and this endopeptidase activity is lost in the PRB1 deletion mutant (prb1Δ). In addition, like Cathepsin L and GDH, purified Prb1 from yeast cleaves H3 between Lys23 and Ala24 in the N-terminus in vitro as shown by Edman degradation. In conclusion, our data argue that PRB1 is required for clipping of the histone H3 N-terminal tail in Saccharomyces cerevisiae.

  18. SwissProt search result: AK119888 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK119888 002-179-H09 (P43150) Leishmanolysin C1 precursor (EC 3.4.24.36) (Cell surface protease) (Major surf...ace glycoprotein) (Protein gp63) (Promastigote surface endopeptidase) (Major surface protease) GP63_LEIME 2e-42 ...

  19. Enzymatically Degradable Hybrid Organic-Inorganic Bridged Silsesquioxane Nanoparticles for In-Vitro Imaging

    KAUST Repository

    Fatieiev, Yevhen

    2015-06-30

    Non-aggregated dense bridged silsesquioxane (BS) nanoparticles based on nature-inspired oxamide bridges are shown to degrade in simulated biological media upon cleavage with endopeptidase. Fluorescent BS nanoprobes with incorporated fluorescein dyes were applied for in-vitro imaging in cancer cells.

  20. LOCALIZATION OF PEPTIDASES IN LACTOCOCCI

    NARCIS (Netherlands)

    TAN, PST; CHAPOTCHARTIER, MP; POS, KM; ROUSSEAU, M; BOQUIEN, CY; GRIPON, JC; KONINGS, WN

    1992-01-01

    The localization of two aminopeptidases, an X-prolyl-dipeptidyl aminopeptidase, an endopeptidase, and a tripeptidase in Lactococcus lactis was studied. Polyclonal antibodies raised against each purified peptidase are specific and do not cross-react with other peptidases. Experiments were performed b

  1. EST Table: BP120057 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available BP120057 ceN-1674 11/12/09 GO hit GO:0004197(cysteine-type endopeptidase activity)|...P_973607.2| PREDICTED: similar to cathepsin F-like cysteine protease [Tribolium castaneum] BP120057 ceN- ...

  2. Penicillin-binding protein 4 of Escherichia coli shows a novel type of primary structure among penicillin-interacting proteins

    NARCIS (Netherlands)

    Mottl, H.; Terpstra, P.; Keck, W.

    1991-01-01

    The nucleotide sequence of a 1884 bp DNA fragment of E. coli, carrying the gene dacB, was determined. The DNA codes for penicillin-binding protein 4 (PBP4), an enzyme of 477 amino acids, being involved as a DD-carboxypeptidase-endopeptidase in murein metabolism. The enzyme is translated with a cleav

  3. KIDNEY AND URINARY TRACT

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    10.1 Kidney function2004116 Measurement of urinary neutral endopeptid-ase and its significance in diagnosing renal tubular injury. ZHANG Zhi (张智), et al. Div Nephrol, Ruijin Hosp, Shanghai 2nd Med Univ, Shanghai 200025. Chin J Nephrol 2003; 19(6) :392-396.

  4. Purification and characterization of a papaya (Carica papaya L.) pectin methylesterase isolated from a commercial papain preparation

    Science.gov (United States)

    We purified a single stable pectin methylesterase (CpL-PME; EC 3.1.1.11) from a commercial papain preparation, which is isolated from Carica papaya (L.) fruit latex. This CpL-PME was separated from the abundant cysteine endopeptidases activities using sequential hydrophobic interaction and cation-ex...

  5. Development of an integrated system for activity-based profiling of matrix metallo-proteases

    NARCIS (Netherlands)

    Freije, Jan Robert

    2006-01-01

    Matrix metallo-proteases constitute a family of extracellular zinc-dependent endopeptidases that are involved in degradation of extracellular matrix (ECM) components and other bioactive non-ECM molecules. A plethora of studies have implicated important roles for MMPs in many diseases (including canc

  6. SLV-306. Solvay.

    Science.gov (United States)

    Tabrizchi, Reza

    2003-03-01

    SLV-306 is an orally active mixed neutral endopeptidase/endothelin converting enzyme inhibitor under development by Solvay SA for the potential treatment of essential hypertension and congestive heart failure. The compound is currently undergoing phase II clinical trials in Belgium.

  7. Ubiquitin, a central component of selective cytoplasmic proteolysis, is linked to proteins residing at the locus of non-selective proteolysis, the vacuole

    NARCIS (Netherlands)

    Simeon, Angela; Klei, Ida J. van der; Veenhuis, Marten; Wolf, Dieter H.

    1992-01-01

    Ubiquitin, an evolutionary highly conserved protein, is known to be involved in selective proteolysis in the cytoplasm. Here we show that ubiquitin-protein conjugates are also found in the yeast vacuole. Mutants defective in the major vacuolar endopeptidases, proteinase yscA and yscB, lead to accumu

  8. Influence of heavy metals on biosynthesis, activity of lytic enzymes and growthstimulating factor of Streptomyces recifensis var. lyticus P-29

    Directory of Open Access Journals (Sweden)

    Т. P. Kilochok

    2005-02-01

    Full Text Available Influence of heavy metals on growth, biosynthesis, lytic action and growthstimulating activity enzymes complex of Streptomyces recifensis var. lyticus was studied. It was showed that salt of plumbum' has positive influence as on biosynthesis hydrolases (lytic endopeptidases, proteinases, amylases as well increase growthstimulating activity of preparation relatively the yeast

  9. UniProt search blastx result: AK289220 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK289220 J100065H20 P05994|PAPA4_CARPA Papaya proteinase 4 precursor (EC 3.4.22.25) (Papay...a proteinase IV) (PPIV) (Papaya peptidase B) (Glycyl endopeptidase) - Carica papaya (Papaya) 1.00E-57 ...

  10. Characterization of two cysteine proteases secreted by Blastocystis ST7, a human intestinal parasite.

    Science.gov (United States)

    Wawrzyniak, Ivan; Texier, Catherine; Poirier, Philippe; Viscogliosi, Eric; Tan, Kevin S W; Delbac, Frédéric; El Alaoui, Hicham

    2012-09-01

    Blastocystis spp. are unicellular anaerobic intestinal parasites of both humans and animals and the most prevalent ones found in human stool samples. Their association with various gastrointestinal disorders raises the questions of its pathogenicity and of the molecular mechanisms involved. Since secreted proteases are well-known to be implicated in intestinal parasite virulence, we intended to determine whether Blastocystis spp. possess such pathogenic factors. In silico analysis of the Blastocystis subtype 7 (ST7) genome sequence highlighted 22 genes coding proteases which were predicted to be secreted. We characterized the proteolytic activities in the secretory products of Blastocystis ST7 using specific protease inhibitors. Two cysteine proteases, a cathepsin B and a legumain, were identified in the parasite culture supernatant by gelatin zymographic SDS-PAGE gel and MS/MS analysis. These proteases might act on intestinal cells and disturb gut function. This work provides serious molecular candidates to link Blastocystis spp. and intestinal disorders.

  11. Electrochemical enzymatic biosensors using carbon nanofiber nanoelectrode arrays

    Science.gov (United States)

    Li, Jun; Li, Yi-fen; Swisher, Luxi Z.; Syed, Lateef U.; Prior, Allan M.; Nguyen, Thu A.; Hua, Duy H.

    2012-10-01

    The reduction of electrode size down to nanometers could dramatically enhance detection sensitivity and temporal resolution. Nanoelectrode arrays (NEAs) are of particular interest for ultrasensitive biosensors. Here we report the study of two types of biosensors for measuring enzyme activities using NEAs fabricated with vertically aligned carbon nanofibers (VACNFs). VACNFs of ~100 nm in average diameter and 3-5 μm in length were grown on conductive substrates as uniform vertical arrays which were then encapsulated in SiO2 matrix leaving only the tips exposed. We demonstrate that such VACNF NEAs can be used in profiling enzyme activities through monitoring the change in electrochemical signals induced by enzymatic reactions to the peptides attached to the VACNF tip. The cleavage of the tetrapeptide with a ferrocene tag by a cancerrelated protease (legumain) was monitored with AC voltammetry. Real-time electrochemical impedance spectroscopy (REIS) was used for fast label-free detection of two reversible processes, i.e. phosphorylation by c-Src tyrosine kinase and dephosphorylation by protein tyrosine phosphatase 1B (PTP1B). The REIS data of phosphorylation were slow and unreliable, but those of dephosphorylation showed large and fast exponential decay due to much higher activity of phosphatase PTP1B. The kinetic data were analyzed with a heterogeneous Michaelis-Menten model to derive the "specificity constant" kcat/Km, which is 8.2x103 M-1s-1 for legumain and (2.1 ± 0.1) x 107 M-1s-1 for phosphatase (PTP1B), well consistent with literature. It is promising to develop VACNF NEA based electrochemical enzymatic biosensors as portable multiplex electronic techniques for rapid cancer diagnosis and treatment monitoring.

  12. Identification by FT-ICR-MS of Camelus dromedarius α-lactalbumin variants as the result of nonenzymatic deamidation of Asn-16 and Asn-45.

    Science.gov (United States)

    Si Ahmed Zennia, Saliha; Mati, Abderrahmane; Saulnier, Franck; Verdier, Yann; Chiappetta, Giovanni; Mulliert, Guillermo; Miclo, Laurent; Vinh, Joëlle; Girardet, Jean-Michel

    2015-11-15

    Nonenzymatic deamidation of asparaginyl residues can occur spontaneously under physiological conditions principally when a glycyl residue is at the carboxyl side of Asn and leads to formation of aspartyl and isoaspartyl residues. This modification can change the biological activity of proteins or peptides and trigger an auto-immune response. The α-lactalbumins of members of the Camelidae family are the only of described α-lactalbumins that carry two AsnGly sequences. In the present study, high-resolution mass spectrometry, which enables accurate mass measurement has shown that Asn(16) and Asn(45) underwent a nonenzymatic deamidation, the sequence Asn(45)-Gly(46) being deamidated spontaneously at near-neutral and basic pH and Asn(16)-Gly(17) rather at basic pH. The 16-17 sequence was probably stabilized at near-neutral pH by hydrogen bonds according to the molecular modelisation performed with the camel protein.

  13. HIF hydroxylase pathways in cardiovascular physiology and medicine.

    Science.gov (United States)

    Bishop, Tammie; Ratcliffe, Peter J

    2015-06-19

    Hypoxia inducible factors (HIFs) are α/β heterodimeric transcription factors that direct multiple cellular and systemic responses in response to changes in oxygen availability. The oxygen sensitive signal is generated by a series of iron and 2-oxoglutarate-dependent dioxygenases that catalyze post-translational hydroxylation of specific prolyl and asparaginyl residues in HIFα subunits and thereby promote their destruction and inactivation in the presence of oxygen. In hypoxia, these processes are suppressed allowing HIF to activate a massive transcriptional cascade. Elucidation of these pathways has opened several new fields of cardiovascular research. Here, we review the role of HIF hydroxylase pathways in cardiac development and in cardiovascular control. We also consider the current status, opportunities, and challenges of therapeutic modulation of HIF hydroxylases in the therapy of cardiovascular disease.

  14. Potential matrix metalloproteinase inhibitors from edible marine algae: a review.

    Science.gov (United States)

    Thomas, Noel Vinay; Manivasagan, Panchanathan; Kim, Se-Kwon

    2014-05-01

    Matrix metalloproteinases are endopeptidases which belong to the group of metalloproteinases that contribute for the extra-cellular matrix degradation, and several tissue remodeling processes. An imbalance in the regulation of these endopeptidases eventually leads to several severe pathological complications like cancers, cardiac, cartilage, and neurological related diseases. Hence inhibitory substances of metalloproteinases (MMPIs) could prove beneficial in the management of above specified pathological conditions. The available synthetic MMPIs that have been reported until now have few shortcomings and thus many of them could not make to the final clinical trials. Hence a growing interest among researchers on screening of MMPIs from different natural resources is evident and especially natural products from marine origin. As there has been an unparalleled contribution of several biologically active compounds from marine resources that have shown profound applications in nutraceuticals, cosmeceuticals, and pharmaceuticals, we have attempted to discuss the various MMPIs from edible sea-weeds. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Fucoidans from marine algae as potential matrix metalloproteinase inhibitors.

    Science.gov (United States)

    Thomas, Noel Vinay; Kim, Se-Kwon

    2014-01-01

    Matrix metalloproteinases are endopeptidases which belong to the group of metalloproteinases that contribute for the extracellular matrix degradation and several tissue remodeling processes. An imbalance in the regulation of these endopeptidases eventually leads to several severe pathological complications like cancers, cardiac, cartilage, and neurological-related diseases. Hence, inhibitory substances of metalloproteinases (MMPIs) could prove beneficial in the management of above specified pathological conditions. The available synthetic MMPIs that have been reported until now have few shortcomings, and thus many of them could not make to the final clinical trials. Hence, a growing interest among researchers on screening of MMPIs from different natural resources is evident and especially natural products from marine origin. As there has been an unparalleled contribution of several biologically active compounds from marine resources that have shown a profound applications in nutraceuticals, cosmeceuticals, and pharmaceuticals, we have attempted to discuss the various MMPIs from edible seaweeds. © 2014 Elsevier Inc. All rights reserved.

  16. A highly sensitive peptide substrate for detecting two Aß-degrading enzymes: neprilysin and insulin-degrading enzyme.

    Science.gov (United States)

    Chen, Po-Ting; Liao, Tai-Yan; Hu, Chaur-Jong; Wu, Shu-Ting; Wang, Steven S-S; Chen, Rita P-Y

    2010-06-30

    Neprilysin has been singled out as the most promising candidate for use in the degradation of Abeta as a therapy for Alzheimer's disease. In this study, a quenched fluorogenic peptide substrate containing the first seven residues of the Abeta peptide plus a C-terminal Cysteine residue was synthesized to detect neprilysin activity. A fluorophore was attached to the C-terminal Cysteine and its fluorescence was quenched by a quencher linked to the N-terminus of the peptide. When this peptide substrate was degraded by an endopeptidase, fluorescence was produced and proved to be a sensitive detection system for endopeptidase activity. Our results showed that this assay system was extremely sensitive to neprilysin and insulin-degrading enzyme, but insensitive, or much less sensitive, to other Abeta-degrading enzymes. As low as 0.1 nM of neprilysin and 0.2 nM of insulin-degrading enzyme can be detected.

  17. Aeromonas proteolyrica bacteria in aerospace environments. [possible genetic alterations and effects on man

    Science.gov (United States)

    Foster, B. G.

    1974-01-01

    Preflight studies on Aeromonas proteolytica are reported to investigate the possibility of genetic alterations resulting in increased proteolysis in spacecraft environments. This organism may be present on human tissue and could pose medical problems if its endopeptidase and a hemolysin were to be produced in ususually high quantities or altered in such a way as to be more effective in their activities. Considered are: (1) Development of a nutrative holding medium for suspension of organisms; (2) the establishment of baseline information for the standardization of the assay for endopeptidase levels and hemolytic titers; (3) formulation of a method by which intracutaneous hemorrhage could be quantitated in guinea pig tissue; and (4) the responses of these organisms to parameters of spaceflight and experimentation.

  18. First natural urease inhibitor from Euphorbia decipiens.

    Science.gov (United States)

    Ahmad, Viqar Uddin; Hussain, Javid; Hussain, Hidayat; Jassbi, Amir Reza; Ullah, Farman; Lodhi, Muhammad Arif; Yasin, Amsha; Choudhary, Muhammad Iqbal

    2003-06-01

    Three new diterpene esters with a myrsinol-type skeleton have been isolated from Euphorbia decipiens BOISS. & BUHSE. The structure elucidation of the isolated compounds was based primarily on two-dimensional (2D)-NMR techniques including correlation spectroscopy (COSY), heteronuclear multiple quantum coherence (HMQC), heteronuclear multiple bond correlation (HMBC) and nuclear Overhauser effect spectroscopy (NOESY) experiments. Compounds 1 and 3 are active against prolyl endopeptidase and compound 2 showed inhibitory activity against urease enzyme.

  19. Lytr, a phage-derived amidase is most effective in induced lysis of Lactococcus lactis compared with other lactococcal amidases and glucosaminidases

    NARCIS (Netherlands)

    Steen, Anton; van Schalkwijk, Saskia; Buist, Girbe; Twigt, Marja; Szeliga, Monika; Meijer, Wilco; Kuipers, Oscar P.; Kok, Jan; Hugenholtz, Jeroen

    2007-01-01

    In the genome of Lactococcus lactis IL1403 five genes encoding peptidoglycan hydrolases are present: four glucosaminidases (acmA, acmB, acmC and acmD) and an endopeptidase (yjgB). Genes for six prophage lysins have also been identified. The genes acmB, acmC, acmD, yjgB and the lysin lytR of prophage

  20. Peptidases prevent μ-opioid receptor internalization in dorsal horn neurons by endogenously released opioids

    OpenAIRE

    Song, Bingbing; Marvizón, Juan Carlos G.

    2003-01-01

    To evaluate the effect of peptidases on μ-opioid receptor (MOR) activation by endogenous opioids, we measured MOR-1 internalization in rat spinal cord slices. A mixture of inhibitors of aminopeptidases (amastatin), dipeptidyl carboxypeptidase (captopril), and neutral endopeptidase (phosphoramidon) dramatically increased the potencies of Leu-enkephalin and dynorphin A to produce MOR-1 internalization, and also enhanced the effects of Met-enkephalin and α-neoendorphin, but not endomorphins or β...

  1. IFN-γ Regulation of Vacuolar pH, Cathepsin D Processing and Autophagy in Mammary Epithelial Cells

    OpenAIRE

    2008-01-01

    In this study we examined the ability of interferon-γ (IFN-γ) to regulate mammary epithelial cell growth and gene expression, with particular emphasis on two genes: Maspin (a member of serine protease inhibitor superfamily), and the lysosomal aspartyl endopeptidase cathepsin D (CatD). The protein products of these genes are critically involved in regulation of multitude of biological functions in different stages of mammary tissue development and remodeling. In addition, the expression of Mas...

  2. Imaging of Ep-CAM Positive Metastatic Cancer in the Lymph System

    Science.gov (United States)

    2011-01-01

    of the agent into the lymphatic space. One method for generating smaller antibody fragments is papain digestion. Anti-Ep-CAM will be digested...using papain , a specific thiol-endopeptidase that cleaves an antibody on the amino-terminal side of the disulfide bonds that link the two heavy chains...of the molecule. After papain treatment, the original whole antibody will be broken into two Fab fragments and one Fc domain fragment. The Fc

  3. Purification and Characterization of a Substrate-Size-Recognizing Metalloendopeptidase from Streptococcus cremoris H61.

    Science.gov (United States)

    Yan, T R; Azuma, N; Kaminogawa, S; Yamauchi, K

    1987-10-01

    During the ripening of Gouda-type cheese, two kinds of endopeptidases were found to participate in the degradation of alphas1-CN(f1-23), a specific product from alphas1-casein hydrolyzed by chymosin. One of the endopeptidases, lactic acid bacteria endopeptidase (LEP-II), which can recognize the size of its substrates, has already been purified and characterized (T. R. Yan, N. Azuma, S. Kaminogawa, and K. Yamauchi, Eur. J. Biochem. 163:259-265, 1987). The other endopeptidase, LEP-I, was purified to homogeneity by conventional chromatographic techniques from Streptococcus cremoris H61. The enzyme appeared to be monomeric, with an apparent molecular weight of 98,000, and its isoelectric point was 5.1. For the hydrolysis of alphas1-CN(f1-23), the enzyme had an optimum pH and temperature of 7.0 to 7.5 and 40 degrees C, respectively. Its activity was inhibited by such chelating agents as EDTA and 1,10-phenanthrolin, and it could be fully reactivated by Mn. Inhibitors specific for serine and thiol proteases had no effect on the protease activity. The enzyme showed a high affinity toward the Glu-Asn peptide bond of alphas1-CN(f1-23) and alphas1-CN(f91-100) but showed no hydrolysis activity toward alphas1-CN(f1-52), alphas1-CN(61-122), alphas1-CN(136-196), alphas1-casein, beta-casein, kappa-casein, alpha-lactalbumin, and beta-lactoglobulin. The K(m) and V(max) of LEP-I for alphas1-CN(f1-23) were 14.2 pM and 139 U, respectively.

  4. Bioassay studies of 2'-O-ethylmurrangatin isolated from a medicinal plant, Murraya paniculata

    OpenAIRE

    SHAIKH, Azizuddin; Choudhary, Muhammad Iqbal

    2011-01-01

    A secondary metabolite, 2'-O-ethylmurrangatin (1), was isolated from the leaves of a medicinal plant, Murraya paniculata. The structure of compound 1 was identified with the help of spectroscopic techniques. Compound 1 was screened for its antioxidant, lipoxygenase, prolyl endopeptidase, and respiratory burst inhibitory activities. 2'-O-Ethylmurrangatin (1) was found to have significant activity against lipoxygenase enzyme and moderate respiratory burst inhibitory activity, but no a...

  5. Matrix Metalloproteinases And Their Role In Oral Diseases: A Review

    Directory of Open Access Journals (Sweden)

    Anna P. joseph

    2012-01-01

    Full Text Available Matrix metalloproteinases (MMPs are zinc dependent endopeptidases that are capable of degrading extra cellular matrix proteins. The activity of MMPs is seen not only during normal organogenesis and wound healing, but also in pathological conditions like inflammatory diseases and tumor invasion. This review describes the structure, function and regulation of MMPs and also highlights their role in certain oral diseases like oral cancer, periodontitis and dental caries.

  6. Role of Dentin MMPs in Caries Progression and Bond Stability

    OpenAIRE

    A. Mazzoni; Tjäderhane, L.; Checchi, V.; Di Lenarda, R.; Salo, T.; Tay, F.R.; Pashley, D.H.; Breschi, L

    2015-01-01

    Dentin can be described as a biological composite with collagen matrix embedded with nanosized hydroxyapatite mineral crystallites. Matrix metalloproteinases (MMPs) and cysteine cathepsins are families of endopeptidases. Enzymes of both families are present in dentin and collectively capable of degrading virtually all extracellular matrix components. This review describes these enzymes and their presence in dentin, mainly focusing on their role in dentin caries pathogenesis and loss of collag...

  7. Proteomic profiling of pretreatment serum from HIV-infected patients identifies candidate markers predictive of lymphoma development

    DEFF Research Database (Denmark)

    Vase, Maja Ølholm; Ludvigsen, Maja; Bendix, Knud;

    2016-01-01

    Objective: HIV-infected individuals have an increased risk of developing lymphoma. We sought to identify markers predictive of lymphoma development by comparing protein expression patterns in serum obtained at the time of HIV diagnosis from patients who later developed malignant lymphoma or benign...... protein spots were detected. Using principal components analysis, spots containing immunoglobulin J chain, apolipoprotein A-I, procollagen C-endopeptidase enhancer-1 and complement C4-A were associated with lymphoma development (P...

  8. Ricinosomes: an organelle for developmentally regulated programmed cell death in senescing plant tissues

    Science.gov (United States)

    Gietl, C.; Schmid, M.

    2001-02-01

    This review describes aspects of programmed cell death (PCD). Present research maps the enzymes involved and explores the signal transduction pathways involved in their synthesis. A special organelle (the ricinosome) has been discovered in the senescing endosperm of germinating castor beans (Ricinus communis) that develops at the beginning of PCD and delivers large amounts of a papain-type cysteine endopeptidase (CysEP) in the final stages of cellular disintegration. Castor beans store oil and proteins in a living endosperm surrounding the cotyledons. These stores are mobilized during germination and transferred into the cotyledons. PCD is initiated after this transfer is complete. The CysEP is synthesized in the lumen of the endoplasmic reticulum (ER) where it is retained by its C-terminal KDEL peptide as a rather inactive pro-enzyme. Large number of ricinosomes bud from the ER at the same time as the nuclear DNA is characteristically fragmented during PCD. The mitochondria, glyoxysomes and ribosomes are degraded in autophagic vacuoles, while the endopeptidase is activated by removal of the propeptide and the KDEL tail and enters the cytosol. The endosperm dries and detaches from the cotyledons. A homologous KDEL-tailed cysteine endopeptidase has been found in several senescing tissues; it has been localized in ricinosomes of withering day-lily petals and dying seed coats. Three genes for a KDEL-tailed cysteine endopeptidase have been identified in Arabidopsis. One is expressed in senescing ovules, the second in the vascular vessels and the third in maturing siliques. These genes open the way to exploring PCD in plants.

  9. Peptide hydrolase system of lactic acid bacteria isolated from Serra da Estrela cheese

    OpenAIRE

    Macedo, Angela C.; Veira, Marta; Poças, Raquel; Malcata, F. X.

    2000-01-01

    Lactobacillus paracasei subsp. paracasei ESB 230, Leuconostoc mesenteroides subsp. mesenteroides ESB 136, Lactococcus lactis subsp. lactis ESB 117 and Enterococcus faecium ESB 50, previously isolated from certi"ed Serra da Estrela cheeses, were tested for their aminopeptidase, dipeptidyl aminopeptidase, endopeptidase, dipeptidase and carboxypeptidase activities. The crude cell-free extracts (CFE) of Lb. paracasei ESB 230 exhibited the highest aminopeptidase activity, followed by CFE ...

  10. Metabolic inactivation of the circadian transmitter, pigment dispersing factor (PDF), by neprilysin-like peptidases in Drosophila.

    Science.gov (United States)

    Isaac, R Elwyn; Johnson, Erik C; Audsley, Neil; Shirras, Alan D

    2007-12-01

    Recent studies have firmly established pigment dispersing factor (PDF), a C-terminally amidated octodecapeptide, as a key neurotransmitter regulating rhythmic circadian locomotory behaviours in adult Drosophila melanogaster. The mechanisms by which PDF functions as a circadian peptide transmitter are not fully understood, however; in particular, nothing is known about the role of extracellular peptidases in terminating PDF signalling at synapses. In this study we show that PDF is susceptible to hydrolysis by neprilysin, an endopeptidase that is enriched in synaptic membranes of mammals and insects. Neprilysin cleaves PDF at the internal Ser7-Leu8 peptide bond to generate PDF1-7 and PDF8-18. Neither of these fragments were able to increase intracellular cAMP levels in HEK293 cells cotransfected with the Drosophila PDF receptor cDNA and a firefly luciferase reporter gene, confirming that such cleavage results in PDF inactivation. The Ser7-Leu8 peptide bond was also the principal cleavage site when PDF was incubated with membranes prepared from heads of adult Drosophila. This endopeptidase activity was inhibited by the neprilysin inhibitors phosphoramidon (IC(50,) 0.15 micromol l(-1)) and thiorphan (IC(50,) 1.2 micromol l(-1)). We propose that cleavage by a member of the Drosophila neprilysin family of endopeptidases is the most likely mechanism for inactivating synaptic PDF and that neprilysin might have an important role in regulating PDF signals within circadian neural circuits.

  11. Amyloid beta and Alzheimer’s Disease: The role of neprilysin-2 in amyloid-beta clearance

    Directory of Open Access Journals (Sweden)

    Robert eMarr

    2014-08-01

    Full Text Available Accumulation of the amyloid-beta (Ab peptide is a central factor in Alzheimer’s disease (AD pathogenesis as supported by continuing evidence. This review concisely summarizes this evidence supporting a critical role for Ab in AD before discussing the clearance of this peptide. Mechanisms of clearance of Ab are critical for preventing pathological elevations in Ab concentration. Direct degradation of Ab by endopeptidases has emerged as one important pathway for clearance. Of particular interest are endopeptidases that are sensitive to the neprilysin (NEP inhibitors thiorphan and phosphoramidon (i.e. are NEP-like as these inhibitors induce a dramatic increase in Ab levels in rodents. This review will focus on Neprilysin-2 (NEP2, a NEP-like endopeptidase which cooperates with NEP to control Ab levels in the brain. The evidence for the involvement of NEP2 in AD is discussed as well as the therapeutic relevance with regards to gene therapy and the development of molecular markers for the disease.

  12. Synthesis and analgesic effects of N-[3-[(hydroxyamino) carbonyl]-1-oxo-2(R)-benzylpropyl]-L-isoleucyl-L-leucine, a new potent inhibitor of multiple neurotensin/neuromedin N degrading enzymes.

    Science.gov (United States)

    Doulut, S; Dubuc, I; Rodriguez, M; Vecchini, F; Fulcrand, H; Barelli, H; Checler, F; Bourdel, E; Aumelas, A; Lallement, J C

    1993-05-14

    The synthesis of N-[3-[(hydroxyamino) carbonyl]-1-oxo-2(R)-benzylpropyl]-L-isoleucyl-L-leucine (JMV-390-1, 6a), a multipeptidase inhibitor based on the C-terminal sequence common to neurotensin (NT) and neuromedin N (NN), is described. This compound behaves as a full inhibitor of the major NT/NN degrading enzymes in vitro, e.g. endopeptidase 24.16, endopeptidase 24.15, endopeptidase 24.11, and leucine aminopeptidase (type IV-S), in the nanomolar range (IC50's from 30 to 60 nM). Compound 6a was found to increase endogenous recovery of NT and NN from slices of mice hypothalamus depolarized with potassium. In various assays commonly used to select analgesics, e.g. hot-plate test, tail-flick test, acetic acid-induced writhing test, in mice, compound 6a proved to be potent when intracerebroventricularly (icv) injected. The analgesic effects observed were totally (hot-plate test) or largely (tail-flick test) reversed by the opioid antagonist naltrexone. Furthermore, icv injection of compound 6a (10 micrograms/mouse) was found to significantly potentiate the hypothermic effects of NT or NN.

  13. The specificity of viral sialidases. The use of oligosaccharide substrates to probe enzymic characteristics and strain-specific differences.

    Science.gov (United States)

    Corfield, A P; Wember, M; Schauer, R; Rott, R

    1982-06-01

    1. The action of sialidases from Newcastle disease virus (NDV), influenza A2 virus (IA2V) and fowl plague virus (FPV) on sialyloligosaccharide substrates containing alpha 2-3, alpha 2-6 or alpha 2-8 linkages was studied. 2. In all cases 2-3-linked sialic acids were preferentially released. Compared with II6Neu5AcLac, all 2-6-linked substrates, including sialyl-N-acetyllactosamine and its asparaginyl derivative, a urinary hexasaccharide and Neu5Ac(2-6)GalNAc were cleaved at improved rates by NDV and less by FPV sialidases. In the case of IA2V sialidase the asparaginyl oligosaccharide was very poorly cleaved, illustrating a variation in viral strain specificity. 3. A decrease in relative rates was observed in the order NDV greater than IA2V greater than FPV for substrates with 2-3 linkages relative to II6Neu5AcLac. The greatest relative rate was 470-fold higher. The 2-3-linked sialyl-N-acetyllactosaminylasparagine and IV3Neu5AcLcOse4 were poor substrates for the IA2V sialidase, but the rates were greater than with the 2-6 linked substrates. 4. The ganglioside substrate II3Neu5AcLacCer showed lower activity than its oligosaccharide analogue, but neither II3Neu5AcGgOse4Cer nor its oligosaccharide were substrates. 5. The Km values for 2-6-linked substrates were generally of the order 10 mM while those for the 2-3-linked substrates were approximately 1 mM. The V values were consistently higher for the 2-3-linked substrates. IV3Neu5AcLcOse4 showed high Km and very high V values, while the 2-8-linked disialyllactose showed this trend only with NDV enzyme, the IA2V and FPV sialidases exhibiting high Km and low V values. 6. The results are discussed in the light of the current knowledge of viral sialidase specificity and relative to the binding of virus particles to cell surfaces.

  14. A triticale water-deficit-inducible phytocystatin inhibits endogenous cysteine proteinases in vitro.

    Science.gov (United States)

    Chojnacka, Magdalena; Szewińska, Joanna; Mielecki, Marcin; Nykiel, Małgorzata; Imai, Ryozo; Bielawski, Wiesław; Orzechowski, Sławomir

    2015-02-01

    Water-deficit is accompanied by an increase in proteolysis. Phytocystatins are plant inhibitors of cysteine proteinases that belong to the papain and legumain family. A cDNA encoding the protein inhibitor TrcC-8 was identified in the vegetative organs of triticale. In response to water-deficit, increases in the mRNA levels of TrcC-8 were observed in leaf and root tissues. Immunoblot analysis indicated that accumulation of the TrcC-8 protein occurred after 72h of water-deficit in the seedlings. Using recombinant protein, inhibitory activity of TrcC-8 against cysteine proteases from triticale and wheat tissues was analyzed. Under water-deficit conditions, there are increases in cysteine proteinase activities in both plant tissues. The cysteine proteinase activities were inhibited by addition of the recombinant TrcC-8 protein. These results suggest a potential role for the triticale phytocystatin in modulating cysteine proteinase activities during water-deficit conditions.

  15. Hydrazinocurcumin Encapsuled nanoparticles "re-educate" tumor-associated macrophages and exhibit anti-tumor effects on breast cancer following STAT3 suppression.

    Directory of Open Access Journals (Sweden)

    Xiwen Zhang

    Full Text Available Tumor-associated macrophages (TAMs are essential cellular components within tumor microenvironment (TME. TAMs are educated by TME to transform to M2 polarized population, showing a M2-like phenotype, IL-10(high, IL-12(low, TGF-β(high. STAT3 signaling triggers crosstalk between tumor cells and TAMs, and is crucial for the regulation of malignant progression. In our study, legumain-targeting liposomal nanoparticles (NPs encapsulating HC were employed to suppress STAT3 activity and "re-educate" TAMs, and to investigate the effects of suppression of tumor progression in vivo. The results showed that TAMs treated by HC encapsuled NPs could switch to M1-like phenotype, IL-10(low, IL-12(high, TGF-β(low, and the "re-educated" macrophages (M1-like macrophages considerably demonstrated opposite effect of M2-like macrophages, especially the induction of 4T1 cells migration and invasion in vitro, and suppression of tumor growth, angiogenesis and metastasis in vivo. These data indicated that inhibition of STAT3 activity of TAMs by HC-NPs was able to reverse their phenotype and could regulate their crosstalk between tumor cells and TAMs in order to suppress tumor progression.

  16. Generation of Mature Nα-Terminal Acetylated Thymosin α1 by Cleavage of Recombinant Prothymosin α

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    Bo Liu

    2013-01-01

    Full Text Available Nα-terminal acetylation of peptides plays an important biological role but is rarely observed in prokaryotes. Nα-terminal acetylated thymosin α1 (Tα1, a 28-amino-acid peptide, is an immune modifier that has been used in the clinic to treat hepatitis B and C virus (HBV/HCV infections. We previously documented Nα-terminal acetylation of recombinant prothymosin α (ProTα in E. coli. Here we present a method for production of Nα-acetylated Tα1 from recombinant ProTα. The recombinant ProTα was cleaved by human legumain expressed in Pichia pastoris to release Tα1 in vitro. The Nα-acetylated Tα1 peptide was subsequently purified by reverse phase and cation exchange chromatography. Mass spectrometry indicated that the molecular mass of recombinant Nα-acetylated Tα1 was 3108.79 in, which is identical to the mass of Nα-acetylated Tα1 produced by total chemical synthesis. This mass corresponded to the nonacetylated Tα1 mass with a 42 Da increment. The retention time of recombinant Nα-acetylated Tα1 and chemosynthetic Nα-acetylated Tα1 were both 15.4 min in RP-high performance liquid chromatography (HPLC. These data support the use of an E. coli expression system for the production of recombinant human Nα-acetylated Tα1 and also will provide the basis for the preparation of recombinant acetylated peptides in E. coli.

  17. Cysteine cathepsin activity suppresses osteoclastogenesis of myeloid-derived suppressor cells in breast cancer.

    Science.gov (United States)

    Edgington-Mitchell, Laura E; Rautela, Jai; Duivenvoorden, Hendrika M; Jayatilleke, Krishnath M; van der Linden, Wouter A; Verdoes, Martijn; Bogyo, Matthew; Parker, Belinda S

    2015-09-29

    Cysteine cathepsin proteases contribute to many normal cellular functions, and their aberrant activity within various cell types can contribute to many diseases, including breast cancer. It is now well accepted that cathepsin proteases have numerous cell-specific functions within the tumor microenvironment that function to promote tumor growth and invasion, such that they may be valid targets for anti-metastatic therapeutic approaches. Using activity-based probes, we have examined the activity and expression of cysteine cathepsins in a mouse model of breast cancer metastasis to bone. In mice bearing highly metastatic tumors, we detected abundant cysteine cathepsin expression and activity in myeloid-derived suppressor cells (MDSCs). These immature immune cells have known metastasis-promoting roles, including immunosuppression and osteoclastogenesis, and we assessed the contribution of cysteine cathepsins to these functions. Blocking cysteine cathepsin activity with multiple small-molecule inhibitors resulted in enhanced differentiation of multinucleated osteoclasts. This highlights a potential role for cysteine cathepsin activity in suppressing the fusion of osteoclast precursor cells. In support of this hypothesis, we found that expression and activity of key cysteine cathepsins were downregulated during MDSC-osteoclast differentiation. Another cysteine protease, legumain, also inhibits osteoclastogenesis, in part through modulation of cathepsin L activity. Together, these data suggest that cysteine protease inhibition is associated with enhanced osteoclastogenesis, a process that has been implicated in bone metastasis.

  18. Transcriptome Analysis of the Carmine Spider Mite, Tetranychus cinnabarinus (Boisduval, 1867 (Acari: Tetranychidae, and Its Response to β-Sitosterol

    Directory of Open Access Journals (Sweden)

    Chunya Bu

    2015-01-01

    Full Text Available Tetranychus cinnabarinus (Acari: Tetranychidae is a worldwide polyphagous agricultural pest that has the title of resistance champion among arthropods. We reported previously the identification of the acaricidal compound β-sitosterol from Mentha piperita and Inula japonica. However, the acaricidal mechanism of β-sitosterol is unclear. Due to the limited genetic research carried out, we de novo assembled the transcriptome of T. cinnabarinus using Illumina sequencing and conducted a differential expression analysis of control and β-sitosterol-treated mites. In total, we obtained >5.4 G high-quality bases for each sample with unprecedented sequencing depth and assembled them into 22,941 unigenes. We identified 617 xenobiotic metabolism-related genes involved in detoxification, binding, and transporting of xenobiotics. A highly expanded xenobiotic metabolic system was found in mites. T. cinnabarinus detoxification genes—including carboxyl/cholinesterase and ABC transporter class C—were upregulated after β-sitosterol treatment. Defense-related proteins, such as Toll-like receptor, legumain, and serine proteases, were also activated. Furthermore, other important genes—such as the chloride channel protein, cytochrome b, carboxypeptidase, peritrophic membrane chitin binding protein, and calphostin—may also play important roles in mites’ response to β-sitosterol. Our results demonstrate that high-throughput-omics tool facilitates identification of xenobiotic metabolism-related genes and illustration of the acaricidal mechanisms of β-sitosterol.

  19. Cloning and characterisation of novel cystatins from elapid snake venom glands.

    Science.gov (United States)

    Richards, Renée; St Pierre, Liam; Trabi, Manuela; Johnson, Lambro A; de Jersey, John; Masci, Paul P; Lavin, Martin F

    2011-04-01

    Snake venoms contain a complex mixture of polypeptides that modulate prey homeostatic mechanisms through highly specific and targeted interactions. In this study we have identified and characterised cystatin-like cysteine-protease inhibitors from elapid snake venoms for the first time. Novel cystatin sequences were cloned from 12 of 13 elapid snake venom glands and the protein was detected, albeit at very low levels, in a total of 22 venoms. One highly conserved isoform, which displayed close sequence identity with family 2 cystatins, was detected in each elapid snake. Crude Austrelaps superbus (Australian lowland copperhead) snake venom inhibited papain, and a recombinant form of A. superbus cystatin inhibited cathepsin L ≅ papain > cathepsin B, with no inhibition observed for calpain or legumain. While snake venom cystatins have truncated N-termini, sequence alignment and structural modelling suggested that the evolutionarily conserved Gly-11 of family 2 cystatins, essential for cysteine protease inhibition, is conserved in snake venom cystatins as Gly-3. This was confirmed by mutagenesis at the Gly-3 site, which increased the dissociation constant for papain by 10(4)-fold. These data demonstrate that elapid snake venom cystatins are novel members of the type 2 family. The widespread, low level expression of type 2 cystatins in snake venom, as well as the presence of only one highly conserved isoform in each species, imply essential housekeeping or regulatory roles for these proteins.

  20. Cystatins: biochemical and structural properties, and medical relevance.

    Science.gov (United States)

    Turk, Vito; Stoka, Veronika; Turk, Dusan

    2008-05-01

    The cystatin superfamily comprises a large group of the cystatin domain containing proteins, present in a wide variety of organisms, including humans. Cystatin inhibitory activity is vital for the delicate regulation of normal physiological processes by limiting the potentially highly destructive activity of their target proteases such as the papain (C1) family, including cysteine cathepsins. Some of the cystatins also inhibit the legumain (C13) family of enzymes. Failures in biological mechanisms controlling protease activities result in many diseases such as neurodegeneration, cardiovascular diseases, osteoporosis, arthritis, and cancer. Cystatins have been classified into three types: the stefins, the cystatins and the kininogens, although other cystatin-related proteins, such as CRES proteins, are emerging. The stefins are mainly intracellular proteins, whereas the cystatins and the kininogens are extracellular. The cystatins are tight binding and reversible inhibitors. The basic mechanism of interaction between cystatins and their target proteases has been established, based mainly on the crystal structures of various cathepsins, stefins and cystatins and their enzyme-inhibitor complexes. Cystatins, as rather non-selective inhibitors, discriminate only slightly between endo- and exopeptidases. They are also prone to form amyloids. The levels of some stefins and cystatins in tissue and body fluids can serve as relatively reliable markers for a variety of diseases. In this review we summarize present knowledge about cystatins and their role in some diseases.

  1. Hypoxia. Cross talk between oxygen sensing and the cell cycle machinery.

    Science.gov (United States)

    Semenza, Gregg L

    2011-09-01

    A fundamental physiological property of mammalian cells is the regulation of proliferation according to O(2) availability. Progression through the cell cycle is inhibited under hypoxic conditions in many, but not all, cell types, and this G1 arrest is dependent on hypoxia-inducible factor (HIF) 1α. Components of the hexameric MCM helicase, which binds to replication origins before the onset of DNA synthesis, are present in large excess in mammalian cells relative to origins, suggesting that they may have additional functions. Screens for HIF-1α interacting proteins revealed that MCM7 binds to the amino-terminal PER-SIM-ARNT (PAS) domain of HIF-1α and stimulates prolyl hydroxylation-dependent ubiquitination and degradation of HIF-1α, whereas MCM3 binds to the carboxyl terminus of HIF-1α and enhances asparaginyl hydroxylation-dependent inhibition of HIF-1α transactivation domain function. Thus MCM proteins inhibit HIF activity via two distinct O(2)-dependent mechanisms. Under prolonged hypoxic conditions, MCM mRNA expression is inhibited in a HIF-1α-dependent manner. Thus HIF and MCM proteins act in a mutually antagonistic manner, providing a novel molecular mechanism for homeostatic regulation of cell proliferation based on the relative levels of these proteins.

  2. Potentiometric and spectroscopic studies on the copper(II) complexes of rat amylin fragments. The anchoring ability of specific non-coordinating side chains.

    Science.gov (United States)

    Dávid, Ágnes; Kállay, Csilla; Sanna, Daniele; Lihi, Norbert; Sóvágó, Imre; Várnagy, Katalin

    2015-10-21

    Copper(ii) complexes of peptides modelling the sequence of the 17-22 residues of rat amylin have been studied by potentiometric, UV-Vis, CD and ESR spectroscopic methods. The peptides were synthesized in N-terminally free forms, NH2-VRSSNN-NH2, NH2-VRSSAA-NH2, NH2-VRAANN-NH2, NH2-VRSS-NH2, NH2-SSNN-NH2, NH2-SSNA-NH2 and NH2-AANN-NH2, providing a possibility for the comparison of the metal binding abilities of the amino terminus and the -SSNN- domain. The amino terminus was the primary ligating site in all cases and the formation of only mononuclear complexes was obtained for the tetrapeptides. The thermodynamic stability of the (NH2, N(-), N(-)) coordinated complexes was, however, enhanced by the asparaginyl moiety in the case of NH2-SSNN-NH2, NH2-SSNA-NH2 and NH2-AANN-NH2. Among the hexapeptides the formation of dinuclear complexes was characteristic for NH2-VRSSNN-NH2 demonstrating the anchoring ability of the -SSNN- (SerSerAsnAsn) domain. The complexes of the heptapeptide NH2-GGHSSNN-NH2 were also studied and the data supported the above mentioned anchoring ability of the -SSNN- site.

  3. Similarities of omega gliadins from Triticum urartu to those encoded on chromosome 1A of hexaploid wheat and evidence for their post-translational processing.

    Science.gov (United States)

    DuPont, F M; Vensel, W; Encarnacao, T; Chan, R; Kasarda, D D

    2004-05-01

    The omega-gliadins encoded on chromosome 1 of the A genome were purified from Triticum aestivum L. (2n=6 x=42, AABBDD) cv. Butte86, nullisomic 1D-tetrasomic 1A of cv. Chinese Spring (CS N1DT1A), and the diploid T. urartu (2n=2 x=14, AA ). Reverse-phase high-performance liquid chromatography combined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis of gliadin extracts from CS nullisomic-tetrasomic (NT) lines confirmed the assignment to chromosome 1A. The purified omega-gliadins were characterized by mass spectrometry and N-terminal sequencing. The 1A-encoded omega-gliadins were smaller than 1B- or 1D-encoded omega-gliadins. The N-terminal amino acid sequences for 1A omega-gliadin mature peptides were nearly identical to those for the T. urartu omega-gliadins and were more similar to 1D omega-gliadin sequences than to sequences for T. monococum omega-gliadins, barley C-hordeins, or rye omega-secalins. They diverged greatly from the N-terminal sequences for the 1B omega-gliadins. The data suggest that T. urartu is the A-genome donor, and that post-translational cleavage by an asparaginyl endoprotease produces those omega-gliadins with N-terminal sequences beginning with KEL.

  4. Molecular clocks, molecular profiles, and optimum diets: three approaches to the problem of aging.

    Science.gov (United States)

    Robinson, A B

    1979-02-01

    It has been hypothesized that the deamidation of glutaminyl and asparaginyl residues serves as a molecular clock for many biological processes including protein turnover, development, and aging. At present, this hypothesis has passed some experimental tests which are necessary but not sufficient for its acceptance. The current state of evidence about deamidation as a molecular clock is discussed. In addition, since the molecular biology of aging, especially in humans, is only partly understood, it is of value to develop quantitative, empirical measures of physiological human age and to use these measures to evaluate alternative human living conditions, especially easily adopted alternatives like variations in diet. This may allow some decrease in the suffering and loss from human aging until such time as molecular biology provides superior and more intellectually satisfying answers. An empirical system which consists of quantitative measurement of several hundred human chemical constituents followed by computerized pattern recognition is described. It is hoped that this system will eventually become an aid in the minimization of the rate of human aging through changes in diet and other factors.

  5. Hypoxia and Human Genome Stability: Downregulation of BRCA2 Expression in Breast Cancer Cell Lines

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    Daniele Fanale

    2013-01-01

    Full Text Available Previously, it has been reported that hypoxia causes increased mutagenesis and alteration in DNA repair mechanisms. In 2005, an interesting study showed that hypoxia-induced decreases in BRCA1 expression and the consequent suppression of homologous recombination may lead to genetic instability. However, nothing is yet known about the involvement of BRCA2 in hypoxic conditions in breast cancer. Initially, a cell proliferation assay allowed us to hypothesize that hypoxia could negatively regulate the breast cancer cell growth in short term in vitro studies. Subsequently, we analyzed gene expression in breast cancer cell lines exposed to hypoxic condition by microarray analysis. Interestingly, genes involved in DNA damage repair pathways such as mismatch repair, nucleotide excision repair, nonhomologous end-joining and homologous recombination repair were downregulated. In particular, we focused on the BRCA2 downregulation which was confirmed at mRNA and protein level. In addition, breast cancer cells were treated with dimethyloxalylglycine (DMOG, a cell-permeable inhibitor of both proline and asparaginyl hydroxylases able to induce HIF-1α stabilization in normoxia, providing results comparable to those previously described. These findings may provide new insights into the mechanisms underlying genetic instability mediated by hypoxia and BRCA involvement in sporadic breast cancers.

  6. Dendrimeric template of Plasmodium falciparum histidine rich protein II repeat motifs bearing Asp→Asn mutation exhibits heme binding and β-hematin formation.

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    Pinky Kumari

    Full Text Available Plasmodium falciparum (Pf employs a crucial PfHRPII catalyzed reaction that converts toxic heme into hemozoin. Understanding heme polymerization mechanism is the first step for rational design of new drugs, targeting this pathway. Heme binding and hemozoin formation have been ascribed to PfHRPII aspartate carboxylate-heme metal ionic interactions. To investigate, if this ionic interaction is indeed pivotal, we examined the comparative heme binding and β-hematin forming abilities of a wild type dendrimeric peptide BNT1 {harboring the native sequence motif of PfHRPII (AHHAHHAADA} versus a mutant dendrimeric peptide BNTM {in which ionic Aspartate residues have been replaced by the neutral Asparaginyl residues (AHHAHHAANA}. UV and IR data reported here reveal that at pH 5, both BNT1 and BNTM exhibit comparable heme binding as well as β-hematin forming abilities, thus questioning the role of PfHRPII aspartate carboxylate-heme metal ionic interactions in heme binding and β-hematin formation. Based on our data and information in the literature we suggest the possible role of weak dispersive interactions like N-H···π and lone-pair···π in heme binding and hemozoin formation.

  7. Characterization of LysB4, an endolysin from the Bacillus cereus-infecting bacteriophage B4

    Directory of Open Access Journals (Sweden)

    Son Bokyung

    2012-03-01

    Full Text Available Abstract Background Bacillus cereus is a foodborne pathogen that causes emetic or diarrheal types of food poisoning. The incidence of B. cereus food poisoning has been gradually increasing over the past few years, therefore, biocontrol agents effective against B. cereus need to be developed. Endolysins are phage-encoded bacterial peptidoglycan hydrolases and have received considerable attention as promising antibacterial agents. Results The endolysin from B. cereus phage B4, designated LysB4, was identified and characterized. In silico analysis revealed that this endolysin had the VanY domain at the N terminus as the catalytic domain, and the SH3_5 domain at the C terminus that appears to be the cell wall binding domain. Biochemical characterization of LysB4 enzymatic activity showed that it had optimal peptidoglycan hydrolase activity at pH 8.0-10.0 and 50°C. The lytic activity was dependent on divalent metal ions, especially Zn2+. The antimicrobial spectrum was relatively broad because LysB4 lysed Gram-positive bacteria such as B. cereus, Bacillus subtilis and Listeria monocytogenes and some Gram-negative bacteria when treated with EDTA. LC-MS analysis of the cell wall cleavage products showed that LysB4 was an L-alanoyl-D-glutamate endopeptidase, making LysB4 the first characterized endopeptidase of this type to target B. cereus. Conclusions LysB4 is believed to be the first reported L-alanoyl-D-glutamate endopeptidase from B. cereus-infecting bacteriophages. The properties of LysB4 showed that this endolysin has strong lytic activity against a broad range of pathogenic bacteria, which makes LysB4 a good candidate as a biocontrol agent against B. cereus and other pathogenic bacteria.

  8. Crystal Structure of the LasA Virulence Factor from Pseudomonas aeruginosa: Substrate Specificity and Mechanism of M23 Metallopeptidases

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, James; Murphy, Loretta M.; Conners, Rebecca; Sessions, Richard B.; Gamblin, Steven J. (Wales); (Bristol Med Sci); (NIMR)

    2010-09-21

    Pseudomonas aeruginosa is an opportunist Gram-negative bacterial pathogen responsible for a wide range of infections in immunocompromized individuals and is a leading cause of mortality in cystic fibrosis patients. A number of secreted virulence factors, including various proteolytic enzymes, contribute to the establishment and maintenance of Pseudomonas infection. One such is LasA, an M23 metallopeptidase related to autolytic glycylglycine endopeptidases such as Staphylococcus aureus lysostaphin and LytM, and to DD-endopeptidases involved in entry of bacteriophage to host bacteria. LasA is implicated in a range of processes related to Pseudomonas virulence, including stimulating ectodomain shedding of the cell surface heparan sulphate proteoglycan syndecan-1 and elastin degradation in connective tissue. Here we present crystal structures of active LasA as a complex with tartrate and in the uncomplexed form. While the overall fold resembles that of the other M23 family members, the LasA active site is less constricted and utilizes a different set of metal ligands. The active site of uncomplexed LasA contains a five-coordinate zinc ion with trigonal bipyramidal geometry and two metal-bound water molecules. Using these structures as a starting point, we propose a model for substrate binding by LasA that explains its activity against a wider range of substrates than those used by related lytic enzymes, and offer a catalytic mechanism for M23 metallopeptidases consistent with available structural and mutagenesis data. Our results highlight how LasA is a structurally distinct member of this endopeptidase family, consistent with its activity against a wider range of substrates and with its multiple roles in Pseudomonas virulence.

  9. Comparative studies of vertebrate endothelin-converting enzyme-like 1 genes and proteins

    Directory of Open Access Journals (Sweden)

    Holmes RS

    2013-01-01

    Full Text Available Roger S Holmes,1,2 Laura A Cox11Department of Genetics and Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA; 2Eskitis Institute for Cell and Molecular Therapies and School of Biomolecular and Physical Sciences, Griffith University, Nathan, Queensland, AustraliaAbstract: Endothelin-converting enzyme-like 1 (ECEL1 is a member of the M13 family of neutral endopeptidases which play an essential role in the neural regulation of vertebrate respiration. Genetic deficiency of this protein results in respiratory failure soon after birth. Comparative ECEL1 amino acid sequences and structures and ECEL1 gene locations were examined using data from several vertebrate genome projects. Vertebrate ECEL1 sequences shared 66%–99% identity as compared with 30%–63% sequence identities with other M13-like family members, ECE1, ECE2, and NEP (neprilysin or MME. Three N-glycosylation sites were conserved among most vertebrate ECEL1 proteins examined. Sequence alignments, conserved key amino acid residues, and predicted secondary and tertiary structures were also studied, including cytoplasmic, transmembrane, and luminal sequences and active site residues. Vertebrate ECEL1 genes usually contained 18 exons and 17 coding exons on the negative strand. Exons 1 and 2 of the human ECEL1 gene contained 5'-untranslated (5'-UTR regions, a large CpG island (CpG256, and several transcription factor binding sites which may contribute to the high levels of gene expression previously reported in neural tissues. Phylogenetic analyses examined the relationships and potential evolutionary origins of the vertebrate ECEL1 gene with six other vertebrate neutral endopeptidase M13 family genes. These suggested that ECEL1 originated in an ancestral vertebrate genome from a duplication event in an ancestral neutral endopeptidase M13-like gene.Keywords: vertebrates, amino acid sequence, ECEL1, ECE1, ECE2, KELL, NEP, NEPL1, PHEX

  10. Kinetics of reactions of the Actinomadura R39 DD-peptidase with specific substrates.

    Science.gov (United States)

    Adediran, S A; Kumar, Ish; Nagarajan, Rajesh; Sauvage, Eric; Pratt, R F

    2011-01-25

    The Actinomadura R39 DD-peptidase catalyzes the hydrolysis and aminolysis of a number of small peptides and depsipeptides. Details of its substrate specificity and the nature of its in vivo substrate are not, however, well understood. This paper describes the interactions of the R39 enzyme with two peptidoglycan-mimetic substrates 3-(D-cysteinyl)propanoyl-D-alanyl-D-alanine and 3-(D-cysteinyl)propanoyl-D-alanyl-D-thiolactate. A detailed study of the reactions of the former substrate, catalyzed by the enzyme, showed DD-carboxypeptidase, DD-transpeptidase, and DD-endopeptidase activities. These results confirm the specificity of the enzyme for a free D-amino acid at the N-terminus of good substrates and indicated a preference for extended D-amino acid leaving groups. The latter was supported by determination of the structural specificity of amine nucleophiles for the acyl-enzyme generated by reaction of the enzyme with the thiolactate substrate. It was concluded that a specific substrate for this enzyme, and possibly the in vivo substrate, may consist of a partly cross-linked peptidoglycan polymer where a free side chain N-terminal un-cross-linked amino acid serves as the specific acyl group in an endopeptidase reaction. The enzyme is most likely a DD-endopeptidase in vivo. pH-rate profiles for reactions of the enzyme with peptides, the thiolactate named above, and β-lactams indicated the presence of complex proton dissociation pathways with sticky substrates and/or protons. The local structure of the active site may differ significantly for reactions of peptides and β-lactams. Solvent kinetic deuterium isotope effects indicate the presence of classical general acid/base catalysis in both acylation and deacylation; there is no evidence of the low fractionation factor active site hydrogen found previously in class A and C β-lactamases.

  11. EST Table: BY926426 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available BY926426 E_ET_F1mg_12A09_R_0 11/12/09 GO hit GO:0003824(catalytic activity)|GO:0004...252(serine-type endopeptidase activity)|GO:0006508(proteolysis) 10/09/28 low homology 10/08/29 n.h 10/08/28 n.h 10/09/10 n.h 10/09/10 n.h 10/09/10 n.h BY926426 F1mg ...

  12. Human ADAM 12 (meltrin alpha) is an active metalloprotease

    DEFF Research Database (Denmark)

    Loechel, F; Gilpin, B J; Engvall, E

    1998-01-01

    in a latent form, probably by means of a cysteine switch. The zymogen could be activated chemically by alkylation with N-ethylmaleimide. Cleavage of the prodomain at a site for a furin-like endopeptidase resulted in an ADAM 12 protein with proteolytic activity. The protease activity was sensitive...... 12 is catalytically active. We used the trapping mechanism of alpha2-macroglobulin to assay for protease activity of wild-type and mutant ADAM 12 proteins produced in a COS cell transfection system. We found that ADAM 12 is synthesized as a zymogen, with the prodomain maintaining the metalloprotease...

  13. Report of a newly indentified patient with mutations in BMP1 and underlying pathogenetic aspects

    DEFF Research Database (Denmark)

    Valencia, María; Caparrós-Martin, Jose A; Sirerol-Piquer, María Salomé;

    2014-01-01

    Osteogenesis imperfecta is a genetic condition characterized by bone fragility and recurrent fractures, which in the large majority of patients are caused by defects in the production of type I collagen. Mutations in the gene encoding bone morphogenetic protein 1 (BMP1, also known as procollagen C......-endopeptidase) have been associated with osteogenesis imperfecta in two sib pairs. In this report, we describe an additional patient with osteogenesis imperfecta with normal bone density and a recurrent, homozygous c.34G>C mutation in BMP1. Western blot analysis of dermal fibroblasts from this patient showed...

  14. Neprilysin inhibition to treat heart failure: a tale of science, serendipity, and second chances.

    Science.gov (United States)

    McMurray, John J V

    2015-03-01

    This review describes the role of neprilysin (also known as neutral endopeptidase or enkephalinase) in the degradation of natriuretic and other vasoactive peptides, including bradykinin and adrenomedullin. The initial development of neprilysin inhibitors, then angiotensin converting enzyme-neprilysin inhibitors and, most recently, the angiotensin receptor neprilysin inhibitor (ARNI) LCZ696 (sacubitril valsartan) as an extension of the nurohumoral basis for the treatment of heart failure is also summarised. Finally, the implications of the compelling benefits of LCZ696 compared with enalapril in the Prospective comparison of ARNI with ACEI to Determine Impact on Global Mortality and morbidity in Heart Failure trial (PARADIGM-HF) is discussed.

  15. Effect of solar irradiation on extracellular enzymes of Aeromonas proteolytica

    Science.gov (United States)

    Foster, B. G.

    1973-01-01

    The bacterium Aeromonas proteolytica was selected for studying the effects of solar irradiation on extracellular enzymes because it produces an endopeptidase that is capable of degrading proteins and a hemolysin that is active in lysing human erythrocytes. Possible alterations in the rate of enzyme production in response to the test conditions are currently underway and are not available for this preliminary report. Completed viability studies are indicative that little difference exists among the survival curves derived for cells exposed to various components of ultraviolet irradiation in space.

  16. Bacterial calpains and the evolution of the calpain (C2) family of peptidases.

    Science.gov (United States)

    Rawlings, Neil D

    2015-11-02

    Homologues of calpain, often thought to be an essential, cytoplasmic, calcium-dependent cysteine endopeptidase found exclusively in eukaryotes, have been found in bacterial proteomes. The homologues lack calcium-binding sites, have differing domain architectures, and can be secreted or membrane-associated. Homologues are rare and occur in a minority of bacterial phyla and often in a minority of species in a genus. However, the differences in domain architecture argue against a recent, horizontal gene transfer from a eukaryote. From analysis of a phylogenetic tree and absence of homologues in archaea, calpains in eukaryotes may be derived from genes horizontally transferred from a bacterium.

  17. Molecular Cloning and Expression Analysis of Triticale Phytocystatins During Development and Germination of Seeds.

    Science.gov (United States)

    Szewińska, Joanna; Zdunek-Zastocka, Edyta; Pojmaj, Mirosław; Bielawski, Wiesław

    2012-01-01

    Three triticale cDNAs encoding inhibitors of cysteine endopeptidases, belonging to phytocystatins, have been identified and designated as TrcC-1, TrcC-4 and TrcC-5. Full-length cDNAs of TrcC-1 (617 bp) and TrcC-4 (940 bp), as well as a fragment of TrcC-5 cDNA (369 bp), were obtained. A high-level identity of the deduced amino acid sequence of TrcCs with other known phytocystatins, especially with wheat and barley, has been observed. Moreover, the presence of conserved domain, containing the G and W residues, the sequence of QxVxG and the sequence of LARFAV, characteristic for plant cysteine endopeptidase inhibitors, has been noted. The profiles of TrcC-1 and TrcC-5 mRNA levels in the developing seeds of two triticale cultivars that differ in their resistance to preharvest sprouting (Zorro and Disco) were similar. However, the expression of TrcC-4 was, higher in the developing seeds, and in the scutellum of germinating seeds of a cultivar more resistant to preharvest sprouting (Zorro) than in the less resistant (Disco). Additionally, the expression of TrcC-4 remained longer in developing seeds of Zorro as compared to Disco. The performed studies suggest that TrcC-4 might have an influence on the higher resistance of Zorro cultivar to preharvest sprouting.

  18. Age-related changes in protein metabolism of beech (Fagus sylvatica L.) seeds during alleviation of dormancy and in the early stage of germination.

    Science.gov (United States)

    Ratajczak, Ewelina; Kalemba, Ewa M; Pukacka, Stanislawa

    2015-09-01

    The long-term storage of seeds generally reduces their viability and vigour. The aim of this work was to evaluate the effect of long-term storage on beech (Fagus sylvatica L.) seeds at optimal conditions, over 9 years, on the total and soluble protein levels and activity of proteolytic enzymes, including endopeptidases, carboxypeptidases and aminopeptidases, as well as free amino acid levels and protein synthesis, in dry seeds, after imbibition and during cold stratification leading to dormancy release and germination. The same analyses were conducted in parallel on seeds gathered from the same tree in the running growing season and stored under the same conditions for only 3 months. The results showed that germination capacity decreased from 100% in freshly harvested seeds to 75% in seeds stored for 9 years. The levels of total and soluble proteins were highest in freshly harvested seeds and decreased significantly during storage, these proportions were retained during cold stratification and germination of seeds. Significant differences between freshly harvested and stored seeds were observed in the activities of proteolytic enzymes, including endopeptidases, aminopeptidases and carboxypeptidases, and in the levels of free amino acids. The neosynthesis of proteins during dormancy release and in the early stage of seed germination was significantly weaker in stored seeds. These results confirm the importance of protein metabolism for seed viability and the consequences of its reduction during seed ageing.

  19. Evolutionary histories of expanded peptidase families in Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Larissa Lopes Silva

    2011-11-01

    Full Text Available Schistosoma mansoni is one of the three main causative agents of human schistosomiasis, a major health problem with a vast socio-economic impact. Recent advances in the proteomic analysis of schistosomes have revealed that peptidases are the main virulence factors involved in the pathogenesis of this disease. In this context, evolutionary studies can be applied to identify peptidase families that have been expanded in genomes over time in response to different selection pressures. Using a phylogenomic approach, we searched for expanded endopeptidase families in the S. mansoni predicted proteome with the aim of contributing to the knowledge of such enzymes as potential therapeutic targets. We found three endopeptidase families that comprise leishmanolysins (metallopeptidase M8 family, cercarial elastases (serine peptidase S1 family and cathepsin D proteins (aspartic peptidase A1 family. Our results suggest that the Schistosoma members of these families originated from successive gene duplication events in the parasite lineage after its diversification from other metazoans. Overall, critical residues are conserved among the duplicated genes/proteins. Furthermore, each protein family displays a distinct evolutionary history. Altogether, this work provides an evolutionary view of three S. mansoni peptidase families, which allows for a deeper understanding of the genomic complexity and lineage-specific adaptations potentially related to the parasitic lifestyle.

  20. Cure of experimental botulism and antibotulismic effect of toosendanin

    Institute of Scientific and Technical Information of China (English)

    Yu-liang SHI; Zhong-feng WANG

    2004-01-01

    Botulinum neurotoxins (BoNTs), a group of bacterial proteins that comprise a light chain disulfide linked aheavy chain, are the most lethal biotoxins known to mankind. By inhibiting neurotransmitter release, BoNTs causesevere neuroparalytic disease, botulism. A series of important findings in the past 10 years which displayed themolecular targets of BoNTs and hence proposed a four-step action mechanism to explain BoNT intoxication greatlyadvanced the study of antibotulismic drug. In this article, we reviewed these progresses and anti-botulismiccompounds found in recent years. These compounds function due to their facilitation on neurotransmitter releaseor to their interference on the binding, internalization, translocation, and endopeptidase activity of the toxins.Toosendanin is a triterpenoid derivative extracted from a digestive tract-parasiticide in Chinese traditional medicine.Chinese scientists have found that the compound is a selective prejunctional blocker. In spite of sharing somesimilar action with BoNT, toosendanin can protect botulism animals that have been administrated with lethal dosesof BoNT/A or BoNT/B for several hours from death and make them restore normal activity. The neuromuscularjunction preparations isolated from the rats that have been injected with toosendanin tolerate BoNT/A challenge.Toosendanin seems to have no effect on endopeptidase activity of BoNT, but blocks the toxin approach to itsenzymatic substrate.

  1. Proteolytic and Trypsin Inhibitor Activity in Germinating Jojoba Seeds (Simmondsia chinensis).

    Science.gov (United States)

    Samac, D; Storey, R

    1981-12-01

    Changes in proteolytic activity (aminopeptidase, carboxypeptidase, endopeptidase) were followed during germination (imbibition through seedling development) in extracts from cotyledons of jojoba seeds (Simmondsia chinensis). After imbibition, the cotyledons contained high levels of sulfhydryl aminopeptidase activity (APA) but low levels of serine carboxypeptidase activity (CPA). CPA increased with germination through the apparent loss of a CPA inhibitor substance in the seed. Curves showing changes in endopeptidase activity (EPA) assayed at pH 4, 5, 6, 7, and 8 during germination were distinctly different. EPA at pH 4, 5, 6, and 7 showed characteristics of sulfhydryl enzymes while activity at pH 8 was probably due to a serine type enzyme. EPA at pH 6 was inhibited early in germination by one or more substances in the seed. Activities at pH 5 and later at pH 6 were the highest of all EPA throughout germination and increases in these activities were associated with a rapid loss of protein from the cotyledons of the developing seedling.Jojoba cotyledonary extracts were found to inhibit the enzymic activity of trypsin, chymotrypsin, and pepsin but not the protease from Aspergillus saotoi. The heat-labile trypsin inhibitor substance(s) was found in commercially processed jojoba seed meal and the albumin fraction of seed proteins. Trypsin inhibitor activity decreased with germination.

  2. Study of air pollution: Effects of ozone on neuropeptide-mediated responses in human subjects. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Boushey, H.A.

    1991-11-01

    The study examined the hypothesis that ozone inactivates the enzyme, neutral endopeptidase, responsible for limiting the effects of neuropeptides released from afferent nerve endings. Cough response of capsaicin solution delivered from a nebulizer at 2 min. intervals until two or more coughs were produced. Other endpoints measured included irritative symptoms as rated by the subjects on a nonparametric scale, spirometry, of each concentration of ozone were compared to those of filtered air in a single-blind randomized sequence. The results indicate that a 2 h. exposure to 0.4 ppm of ozone with intermittent light exercise alters the sensitivity of airway nerves that mediate the cough response to inhaled materials. This dose of ozone also caused a change in FEV1. A lower level of ozone, 0.02 ppm, caused a change in neither cough threshold nor FEV1, even when the duration of exposure was extended to three hours. The findings are consistent with the author's hypothesis that ozone may sensitize nerve endings in the airways by inactivating neutral endopeptidase, an enzyme that regulates their activity, but they do not demonstrate that directly examining an effect directly mediated by airway nerves allows detection of effects of ozone at doses below those causing effects detected by standard tests of pulmonary function.

  3. Characterization of the PH1704 protease from Pyrococcus horikoshii OT3 and the critical functions of Tyr120.

    Science.gov (United States)

    Zhan, Dongling; Bai, Aixi; Yu, Lei; Han, Weiwei; Feng, Yan

    2014-01-01

    The PH1704 protease from hyperthermophilic archaean Pyrococcus horikoshii OT3 is a member of DJ-1/ThiJ/PfpI superfamily with diverse functional subclasses. The recombinant PH1704 was efficiently purified and was systematically characterized by a combination of substrate specificity analysis, steady-state kinetics study and molecular docking research. The homogeneous protease was obtained as a presumed dodecamer with molecular weight of ∼240 kDa. Iodoacetamide strongly inhibited the peptidase activity, confirming that Cys100 is a nucleophilic residue. The recombinant protein was identified as both an aminopeptidase and an endopeptidase. Experimental data showed that L-R-amc was the best substrate of PH1704. Structural interaction fingerprint analysis (SIFt) indicated the binding pose of PH1704 and showed that Tyr120 is important in substrate binding. Kinetic parameters Kcat and Kcat/Km of the Y120P mutant with L-R-amc was about 7 and 7.8 times higher than that of the wild type (WT). For the endopeptidase Y120P with AAFR-amc, Kcat and Kcat/Km is 10- and 21-fold higher than that of WT. Experimental data indicate the important functions of Tyr120: involvement in enzyme activity to form a hydrogen bond with Cys100 and as an entrance gate of the substrate with Lys43. The results of this study can be used to investigate the DJ-1/ThiJ/PfpI superfamily.

  4. A radioactive assay for the degradation of neuropeptide Y

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, R.; Lucius, R.; Mentlein, R. [Kiel Univ. (Germany)

    1995-12-31

    Neuropeptide Y (NPY) is one of the most abundant neuropeptides in the mammalian central nervous system. Like other neuropeptides, NPY is inactivated by specialized neuro-peptidases. To trace the degradation of NPY, an assay was established using biotinylated NPY. Biotinyl-NPY was radiolabeled with Na{sup 125}I by the chloramine-T method and bound to a streptavidin-agarose matrix. The amount of radiolabeling was analyzed by reverse-phase HPLC. The assay was carried out with five peptidases and inhibitors to demonstrate different specific activity. Measurable amounts of radioactivity were released by treatment with endopeptidase-24.18, plasmin, and trypsin, whereas dipetidylpeptidase IV (DPPIV) and angiotensin-converting enzyme (ACE) showed no activity in this assay. In the case of DPPIV this is due to a resistance of the assay to aminopeptidase attack. The assay is useful to study the specific degradation of NPY particularly by endopeptidases in all kinds of biological samples. (authors). 31 refs., 6 figs.

  5. Roles of Matrix Metalloproteinases and Their Natural Inhibitors in Prostate Cancer Progression

    Directory of Open Access Journals (Sweden)

    Yixuan Gong

    2014-06-01

    Full Text Available Matrix metalloproteinases (MMPs, a group of zinc-dependent endopeptidases involved in the degradation of the extracellular matrix, play an important role in tissue remodeling associated with various physiological processes such as morphogenesis, angiogenesis, and tissue repair, as well as pathological processes including cirrhosis, arthritis and cancer. The MMPs are well established as mediators of tumor invasion and metastasis by breaking down connective tissue barriers. Although there has been a vast amount of literature on the role of MMPs in invasion, metastasis and angiogenesis of various cancers, the role of these endopeptidases in prostate cancer progression has not been systematically reviewed. This overview summarizes findings on the tissue and blood expression of MMPs, their function, regulation and prognostic implication in human prostate cancer, with a focus on MMP-2, -7, -9, MT1-MMP and tissue inhibitor of metalloproteinase 1 (TIMP-1. This review also summarizes the efficacy and failure of early-generation matrix metalloproteinase inhibitors (MMPIs in the treatment of metastatic prostate cancer and highlights the lessons and challenges for next generation MMPIs.

  6. Effects of matrix metalloproteinase-1 on the myogenic differentiation of bone marrow-derived mesenchymal stem cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Zhenyang [Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, No. 58, Zhongshan 2nd Road, Guangzhou 510080, Guangdong Province (China); Leng, Yan [Department of Rehabilitation, The First Affiliated Hospital, Sun Yat-sen University, No. 58, Zhongshan 2nd Road, Guangzhou 510080, Guangdong Province (China); Zhou, Chen; Ma, Zhenyu; Zhong, Zhigang [Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, No. 58, Zhongshan 2nd Road, Guangzhou 510080, Guangdong Province (China); Shi, Xing-Ming [Institute of Molecular Medicine and Genetics, Georgia Health Sciences University, Augusta, GA 30912 (United States); Zhang, Weixi, E-mail: weixizhang@qq.com [Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, No. 58, Zhongshan 2nd Road, Guangzhou 510080, Guangdong Province (China)

    2012-11-16

    Highlights: Black-Right-Pointing-Pointer MMP-1 is a member of the zinc-dependent endopeptidase family. Black-Right-Pointing-Pointer MMP-1 has no cytotoxic effects on BMSCs. Black-Right-Pointing-Pointer MMP-1 can promote the myogenic differentiation of BMSCs. Black-Right-Pointing-Pointer MyoD and desmin were chosen as myogenic markers in this study. -- Abstract: Matrix metalloproteinase-1 (MMP-1) is a member of the family of zinc-dependent endopeptidases that are capable of degrading extracellular matrix (ECM) and certain non-matrix proteins. It has been shown that MMP-1 can enhance muscle regeneration by improving the differentiation and migration of myoblasts. However, it is still not known whether MMP-1 can promote the myogenesis of bone marrow-derived mesenchymal stem cells (BMSCs). To address this question, we isolated BMSCs from C57BL/6J mice and investigated the effects of MMP-1 on their proliferation and myogenic differentiation. Our results showed that MMP-1 treatment, which had no cytotoxic effects on BMSCs, increased the mRNA and protein levels of MyoD and desmin in a dose-dependent manner, indicating that MMP-1 promoted myogenic differentiation of BMSCs in vitro. These results suggest that BMSCs may have a therapeutic potential for treating muscular disorders.

  7. Enzymatic cell disruption of microalgae biomass in biorefinery processes.

    Science.gov (United States)

    Demuez, Marie; Mahdy, Ahmed; Tomás-Pejó, Elia; González-Fernández, Cristina; Ballesteros, Mercedes

    2015-10-01

    When employing biotechnological processes for the procurement of biofuels and bio-products from microalgae, one of the most critical steps affecting economy and yields is the "cell disruption" stage. Currently, enzymatic cell disruption has delivered effective and cost competitive results when compared to mechanical and chemical cell disruption methods. However, the introduction of enzymes implies additional associated cost within the overall process. In order to reduce this cost, autolysis of microalgae is proposed as alternative enzymatic cell disruption method. This review aims to provide the state of the art of enzymatic cell disruption treatments employed in biorefinery processes and highlights the use of endopeptidases. During the enzymatic processes of microalgae life cycle, some lytic enzymes involved in cell division and programmed cell death have been proven useful in performing cell lysis. In this context, the role of endopeptidases is emphasized. Mirroring these natural events, an alternative cell disruption approach is proposed and described with the potential to induce the autolysis process using intrinsic cell enzymes. Integrating induced autolysis within biofuel production processes offers a promising approach to reduce overall global costs and energetic input associated with those of current cell disruption methods. A number of options for further inquiry are also discussed. © 2015 Wiley Periodicals, Inc.

  8. 雨生红球藻合成虾青素过程中的分泌铵离子%Concomitant NH+4 Secretion During Astaxanthin Synthesis in Haematococcus pluvialis Under High Irradiance and Nitrogen Deficient Conditions

    Institute of Scientific and Technical Information of China (English)

    董庆霖; 赵学明; 刑向英; 胡建中; 巩继贤

    2007-01-01

    The present study is focused on protein degradation during astaxanthin synthesis in Haematococcus pluvialis under high irradiance and nitrogen deficient conditions. It was found that with the onset of astaxanthin synthesis in the cultures of high light and nitrogen-free (HF), high light and nitrogen-repletion (HR), and low light and nitrogen-free (LF), (1) endopeptidase (EP) activities increased along with decrease in protein content, (2) aspar-agine in HF and HR rose significantly before the first 4 and 5 day, but fell after that time. While, it increased slowly and continuously in LF, (3) ammonium increased continuously in HF and HR, whereas in LF, it was detected on the sixth day, and increased slowly on the following days. By contrast, in low light and nitrogen-repletion culture, (LR), the contents of protein and asparagine as well as EP activity were maintained relatively constant, no astaxanthin and ammonium were detected. Furthermore, when HF was sealed and bubbled with CO2-free gas (O2 and N2), astaxanthin content increased as the protein level decreased. These results strongly suggest that (1) the degraded protein served as a substitutive carbon source, to some extent, for the biosynthesis of astaxanthin, (2) endopeptidase was involved in the degradative process, (3) for detoxification, part of the ammonium generated by protein degradation was transiently stored in asparagine, whereas the rest of it was expelled into the culture broth.

  9. A new brain metalloendopeptidase which degrades the Alzheimer ß-amyloid 1-40 peptide producing soluble fragments without neurotoxic effects

    Directory of Open Access Journals (Sweden)

    K.M. Carvalho

    1997-10-01

    Full Text Available A new metalloendopeptidase was purified to apparent homogeneity from a homogenate of normal human brain using successive steps of chromatography on DEAE-Trisacryl, hydroxylapatite and Sephacryl S-200. The purified enzyme cleaved the Gly33-Leu34 bond of the 25-35 neurotoxic sequence of the Alzheimer ß-amyloid 1-40 peptide producing soluble fragments without neurotoxic effects. This enzyme activity was only inhibited by divalent cation chelators such as EDTA, EGTA and o-phenanthroline (1 mM and was insensitive to phosphoramidon and captopril (1 µM concentration, specific inhibitors of neutral endopeptidase (EC 3.4.24.11 and angiotensin-converting enzyme (EC 3.4.15.1, respectively. The high affinity of this human brain endopeptidase for ß-amyloid 1-40 peptide (Km = 5 µM suggests that it may play a physiological role in the degradation of this substance produced by normal cellular metabolism. It may also be hypothesized that the abnormal accumulation of the amyloid ß-protein in Alzheimer's disease may be initiated by a defect or an inactivation of this enzyme.

  10. A liver metalloendopeptidase which degrades the circulating hypotensive peptide hormones bradykinin and atrial natriuretic peptide

    Directory of Open Access Journals (Sweden)

    Carvalho K.M.

    1999-01-01

    Full Text Available A new metalloendopeptidase was purified to apparent homogeneity from a homogenate of normal human liver using successive steps of chromatography on DEAE-cellulose, hydroxyapatite and Sephacryl S-200. The purified enzyme hydrolyzed the Pro7-Phe8 bond of bradykinin and the Ser25-Tyr26 bond of atrial natriuretic peptide. No cleavage was produced in other peptide hormones such as vasopressin, oxytocin or Met- and Leu-enkephalin. This enzyme activity was inhibited by 1 mM divalent cation chelators such as EDTA, EGTA and o-phenanthroline and was insensitive to 1 µM phosphoramidon and captopril, specific inhibitors of neutral endopeptidase (EC 3.4.24.11 and angiotensin-converting enzyme (EC 3.4.15.1, respectively. With Mr 85 kDa, the enzyme exhibits optimal activity at pH 7.5. The high affinity of this endopeptidase for bradykinin (Km = 10 µM and for atrial natriuretic peptide (Km = 5 µM suggests that it may play a physiological role in the inactivation of these circulating hypotensive peptide hormones.

  11. Proteolytic activity of Elapid and Viperid Snake venoms and its implication to digestion

    Science.gov (United States)

    Bottrall, Joshua L; Madaras, Frank; Biven, Christopher D; Venning, Michael G; Mirtschin, Peter J

    2010-01-01

    Testing whether venoms may aid in digestion of the prey, eleven snake venoms were compared for the presence of proteases and endopeptidases that function in alkaline pH conditions. In vitro experiments examined the relative protease and endopeptidase activity of the venoms, which involved combining bovine muscle and snake venom in a buffered solution, encased within dialysis tubing. This mixture was then incubated at room temperature (∼20°C) for 24hr, with constant shaking. Bicinchoninic acid (BCA) assay and ninhydrin assay were used to determine peptide and amino acid concentrations. Histological and immunohistochemical investigations using N. kaouthia venom confirmed in vitro findings. Results show that B. arietans venom generated the highest amount of protein/peptides and amino acids in the dialysates, while O. scutellatus, N. ater niger and P. textilis venom did not show any significant protein degradation under alkaline conditions. Histological examination revealed varying degrees of muscle cell damage for each of the venom investigated, and the immunohistochemical study on N. kaouthia venom showed that the venom penetrated the muscle tissue to a significant degree. In vitro assays and histological results indicate that particular venoms may possess the ability to enhance digestion of bovine muscle tissue. PMID:21544178

  12. Anti-inflammatory activity of Bromelia hieronymi: comparison with bromelain.

    Science.gov (United States)

    Errasti, María E; Caffini, Néstor O; Pelzer, Lilian E; Rotelli, Alejandra E

    2013-03-01

    Some plant proteases (e. g., papain, bromelain, ficin) have been used as anti-inflammatory agents for some years, and especially bromelain is still being used as alternative and/or complementary therapy to glucocorticoids, nonsteroidal antirheumatics, and immunomodulators. Bromelain is an extract rich in cysteine endopeptidases obtained from Ananas comosus. In this study the anti-inflammatory action of a partially purified extract of Bromelia hieronymi fruits, whose main components are cysteine endopeptidases, is presented. Different doses of a partially purified extract of B. hieronymi were assayed on carrageenan-induced and serotonine-induced rat paw edema, as well as in cotton pellet granuloma model. Doses with equal proteolytic activity of the partially purified extract and bromelain showed significantly similar anti-inflammatory responses. Treatment of the partially purified extract and bromelain with E-64 provoked loss of anti-inflammatory activity on carrageenan-induced paw edema, a fact which is consistent with the hypothesis that the proteolytic activity would be responsible for the anti-inflammatory action.

  13. Label-free electrical determination of trypsin activity by a silicon-on-insulator based thin film resistor.

    Science.gov (United States)

    Neff, Petra A; Serr, Andreas; Wunderlich, Bernhard K; Bausch, Andreas R

    2007-10-08

    A silicon-on-insulator (SOI) based thin film resistor is employed for the label-free determination of enzymatic activity. We demonstrate that enzymes, which cleave biological polyelectrolyte substrates, can be detected by the sensor. As an application, we consider the serine endopeptidase trypsin, which cleaves poly-L-lysine (PLL). We show that PLL adsorbs quasi-irreversibly to the sensor and is digested by trypsin directly at the sensor surface. The created PLL fragments are released into the bulk solution due to kinetic reasons. This results in a measurable change of the surface potential allowing for the determination of trypsin concentrations down to 50 ng mL(-1). Chymotrypsin is a similar endopeptidase with a different specificity, which cleaves PLL with a lower efficiency as compared to trypsin. The activity of trypsin is analyzed quantitatively employing a kinetic model for enzyme-catalyzed surface reactions. Moreover, we have demonstrated the specific inactivation of trypsin by a serine protease inhibitor, which covalently binds to the active site of the enzyme.

  14. Laboratory diagnosis of Schistosomiasis in areas of low transmission: a review of a line of research

    Directory of Open Access Journals (Sweden)

    O Noya

    2002-10-01

    Full Text Available After 57 years of successful control of schistosomiasis in Venezuela, the prevalence and intensity of infection have declined. Approximately 80% of the individuals eliminate less than 100 eggs/g of stools, therefore morbidity is mild and the majority are asymptomatic. The sensitivity of Kato-Katz decreases to approximately 60%. Available serological methods for the detection of circulating antigens only reach a 70% of sensitivity. Tests based on the detection of antibodies by immunoenzymatic assays have been improved. The circumoval precipitine test has shown a high sensitivity (97%, specificity (100%, and correlation with oviposition, being considered the best confirmatory diagnostic test. Additionally to the classical immunoenzymatic assays, the development of the alkaline phosphatase immunoassay, allowed to reach a 100% specificity with an 89% sensitivity. Recently, we have developed a modified ELISA in which the soluble egg antigen is treated with sodium metaperiodate (SMP-ELISA in order to eliminate the glycosilated epitopes responsible for the false positive reactions. The specificity and sensitivity reaches 97% and 99%, respectively. Synthetic peptides from the excretory-secretory enzymes, cathepsin B (Sm31 legumain (Sm32 and cathepsin D (Sm45, have been synthesized. The combination of two peptides derived from the Sm31 have been evaluated, reaching a sensitivity of 96% when analyzed independently and with a 100% specificity. Antibodies raised in rabbits against peptides derived from the Sm31 and Sm32 are currently evaluated in two different antigen-capture-based assays. The development of a simple, cheap and reliable test that correlates with parasite activity is a major goal.

  15. Pathogenic mechanisms in Blastocystis spp. - Interpreting results from in vitro and in vivo studies.

    Science.gov (United States)

    Ajjampur, Sitara S R; Tan, Kevin S W

    2016-12-01

    Blastocystis spp. are commonly reported intestinal protists but whose clinical significance remains controversial. Infections have ranged from asymptomatic carriage to non-specific gastrointestinal symptoms and have also been linked to irritable bowel syndrome and urticaria in some patient populations. In vitro studies showed that both parasite and parasite lysates have damaging effects on intestinal epithelial cells causing apoptosis and degradation of tight junction proteins occludin and ZO1, resulting in increased intestinal permeability. Adhesion of trophic forms to the intestinal epithelium and release of cysteine proteases appear to be the major triggers leading to pathogenesis. Two putative virulence factors identified are cysteine proteases legumain and cathepsin B. Blastocystis spp. also have immuno-modulatory effects including degradation of IgA, inhibition of iNOS and upregulation of proinflammatory cytokines, IL8 and GM-CSF in intestinal epithelial cells and IL1β, IL6 and TNFα in murine macrophages. Blastocystis spp. have also been reported to dampen response to LPS in intestinal epithelial cells and monocytes. Studies in rodent models and naturally infected pigs have shown that the parasite localizes to the lumen and mucosal surface of the large intestine mostly in the caecum and colon. The parasite has been found to cause mucosal sloughing, increase in goblet cell mucin, increased intestinal permeability and to induce a pro-inflammatory cytokine response with upregulation of TNFα, IFNγ and IL12. In this review, we summarize findings from in vitro and in vivo studies that demonstrate pathogenic potential but also show considerable inter and intra subtype variation, which provides a plausible explanation on the conflicting reports on clinical significance. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Characterization of the Entire Cystatin Gene Family in Barley and Their Target Cathepsin L-Like Cysteine-Proteases, Partners in the Hordein Mobilization during Seed Germination1[W

    Science.gov (United States)

    Martinez, Manuel; Cambra, Ines; Carrillo, Laura; Diaz-Mendoza, Mercedes; Diaz, Isabel

    2009-01-01

    Plant cystatins are inhibitors of cysteine-proteases of the papain C1A and legumain C13 families. Cystatin data from multiple plant species have suggested that these inhibitors act as defense proteins against pests and pathogens and as regulators of protein turnover. In this study, we characterize the entire cystatin gene family from barley (Hordeum vulgare), which contain 13 nonredundant genes, and identify and characterize their target enzymes, the barley cathepsin L-like proteases. Cystatins and proteases were expressed and purified from Escherichia coli cultures. Each cystatin was found to have different inhibitory capability against barley cysteine-proteases in in vitro inhibitory assays using specific substrates. Real-time reverse transcription-polymerase chain reaction revealed that inhibitors and enzymes present a wide variation in their messenger RNA expression patterns. Their transcripts were mainly detected in developing and germinating seeds, and some of them were also expressed in leaves and roots. Subcellular localization of cystatins and cathepsin L-like proteases fused to green fluorescent protein demonstrated the presence of both protein families throughout the endoplasmic reticulum and the Golgi complex. Proteases and cystatins not only colocalized but also interacted in vivo in the plant cell, as revealed by bimolecular fluorescence complementation. The functional relationship between cystatins and cathepsin L-like proteases was inferred from their common implication as counterparts of mobilization of storage proteins upon barley seed germination. The opposite pattern of transcription expression in gibberellin-treated aleurones presented by inhibitors and enzymes allowed proteases to specifically degrade B, C, and D hordeins stored in the endosperm of barley seeds. PMID:19759340

  17. [De novo sequencing and analysis of root transcriptome to reveal regulation of gene expression by moderate drought stress in Glycyrrhiza uralensis].

    Science.gov (United States)

    Zhang, Chun-rong; Sang, Xue-yu; Qu, Meng; Tang, Xiao-min; Cheng, Xuan-xuan; Pan, Li-ming; Yang, Quan

    2015-12-01

    Moderate drought stress has been found to promote the accumulation of active ingredients in Glycyrrhiza uralensis root and hence improve the medicinal quality. In this study, the transcriptomes of 6-month-old moderate drought stressed and control G. uralensis root (the relative water content in soil was 40%-45% and 70%-75%, respectively) were sequenced using Illumina HiSeq 2000. A total of 80,490 490 and 82 588 278 clean reads, 94,828 and 305,100 unigenes with N50 sequence of 1,007 and 1,125 nt were obtained in drought treated and control transcriptome, respectively. Differentially expressed genes analysis revealed that the genes of some cell wall enzymes such as β-xylosidase, legumain and GDP-L-fucose synthase were down-regulated indicating that moderate drought stress might inhibit the primary cell wall degradation and programmed cell death in root cells. The genes of some key enzymes involved in terpenoid and flavonoid biosynthesis were up-regulated by moderate drought stress might be the reason for the enhancement for the active ingredients accumulation in G. uralensis root. The promotion of the biosynthesis and signal transduction of auxin, ethylene and cytokinins by moderate drought stress might enhance the root formation and cell proliferation. The promotion of the biosynthesis and signal transduction of abscisic acid and jasmonic acid by moderate drought stress might enhance the drought stress tolerance in G. uralensis. The inhibition of the biosynthesis and signal transduction of gibberellin and brassinolide by moderate drought stress might retard the shoot growth in G. uralensis.

  18. The recombinant prepro region of TvCP4 is an inhibitor of cathepsin L-like cysteine proteinases of Trichomonas vaginalis that inhibits trichomonal haemolysis.

    Science.gov (United States)

    Cárdenas-Guerra, Rosa Elena; Ortega-López, Jaime; Flores-Pucheta, Claudia Ivonne; Benítez-Cardoza, Claudia Guadalupe; Arroyo, Rossana

    2015-02-01

    Trichomonas vaginalis expresses multiple proteinases, mainly of the cysteine type (CPs). A cathepsin L-like 34kDa CP, designated TvCP4, is synthesized as a 305-amino-acid precursor protein. TvCP4 contains the prepro fragment and the catalytic triad that is typical of the papain-like CP family of clan CA. The aim of this work was to determine the function of the recombinant TvCP4 prepro region (ppTvCP4r) as a specific inhibitor of CPs. We cloned, expressed, and purified the recombinant TvCP4 prepro region. The conformation of the purified and refolded ppTvCP4r polypeptide was verified by circular dichroism spectroscopy and fluorescence emission spectra. The inhibitory effect of ppTvCP4r was tested on protease-resistant extracts from T. vaginalis using fluorogenic substrates for cathepsin L and legumain CPs. In 1-D zymograms, the inhibitory effect of ppTvCP4r on trichomonad CP proteolytic activity was observed in the ∼97, 65, 39, and 30 kDa regions. By using 2-D zymograms and mass spectrometry, several of the CPs inhibited by ppTvCP4r were identified. A clear reduction in the proteolytic activity of several cathepsin L-like protein spots (TvCP2, TvCP4, TvCP4-like, and TvCP39) was observed compared with the control zymogram. Moreover, pretreatment of live parasites with ppTvCP4r inhibited trichomonal haemolysis in a concentration dependent manner. These results confirm that the recombinant ppTvCP4 is a specific inhibitor of the proteolytic activity of cathepsin L-like T. vaginalis CPs that is useful for inhibiting virulence properties depending on clan CA papain-like CPs.

  19. Specific Inhibition of the VEGFR-3 Tyrosine Kinase by SAR131675 Reduces Peripheral and Tumor Associated Immunosuppressive Myeloid Cells

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    Espagnolle, Nicolas [UMR5273 INSERM U1031/CNRS/EFS StromaLab, Toulouse 31432 (France); Barron, Pauline; Mandron, Marie; Blanc, Isabelle; Bonnin, Jacques [Sanofi Recherche et Développement, Early to Candidate DPU, Toulouse 31036 (France); Agnel, Magali; Kerbelec, Erwan [Molecular Biology Unit, Biologics Department, Sanofi, Vitry-sur-Seine 94400 (France); Herault, Jean Pascal; Savi, Pierre; Bono, Françoise; Alam, Antoine, E-mail: antoine.alam@sanofi.com [Sanofi Recherche et Développement, Early to Candidate DPU, Toulouse 31036 (France)

    2014-02-28

    Myeloid derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs) represent prominent components in cancer progression. We previously showed that inhibition of the VEGFR-3 pathway by SAR131675 leads to reduction of TAM infiltration and tumor growth. Here, we found that treatment with SAR131675 prevents the accumulation of immunosuppressive blood and splenic MDSCs which express VEGFR-3, in 4T1 tumor bearing mice. Moreover we showed that soluble factors secreted by tumor cells promote MDSCs proliferation and differentiation into M2 polarized F4/80+ macrophages. In addition, cell sorting and transcriptomic analysis of tumor infiltrating myeloid cells revealed the presence of a heterogeneous population that could be divided into 3 subpopulations: (i) immature cells with a MDSC phenotype (GR1+/CD11b+/F4/80{sup −}); (ii) “immuno-incompetent” macrophages (F4/80{sup high}/CD86{sup neg}/MHCII{sup Low}) strongly expressing M2 markers such as Legumain, CD206 and Mgl1/2 and (iii) “immuno-competent”-M1 like macrophages (F4/80{sup Low}/CD86{sup +}/MHCII{sup High}). SAR131675 treatment reduced MDSCs in lymphoid organs as well as F4/80{sup High} populations in tumors. Interestingly, in the tumor SAR131675 was able to increase the immunocompetent M1 like population (F4/80{sup low}). Altogether these results demonstrate that the specific VEGFR-3 inhibitor SAR131675 exerts its anti tumoral activity by acting on different players that orchestrate immunosuppression and cancer progression in a tumoral context: MDSCs in peripheral lymphoid organs and TAMs infiltrating the tumor.

  20. Biochemical, transcriptomic and proteomic analyses of digestion in the scorpion Tityus serrulatus: insights into function and evolution of digestion in an ancient arthropod.

    Science.gov (United States)

    Fuzita, Felipe J; Pinkse, Martijn W H; Patane, José S L; Juliano, Maria A; Verhaert, Peter D E M; Lopes, Adriana R

    2015-01-01

    Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challenge. Understanding the physiology of scorpions can not only lead to evolutionary insights but also is a crucial step in the development of control strategies. However, the digestive process in scorpions has been scarcely studied. In this work, we describe the combinatory use of next generation sequencing, proteomic analysis and biochemical assays in order to investigate the digestive process in the yellow scorpion Tityus serrulatus, mainly focusing in the initial protein digestion. The transcriptome generated database allowed the quantitative identification by mass spectrometry of different enzymes and proteins involved in digestion. All the results suggested that cysteine cathepsins play an important role in protein digestion. Two digestive cysteine cathepsins were isolated and characterized presenting acidic characteristics (pH optima and stability), zymogen conversion to the mature form after acidic activation and a cross-class inhibition by pepstatin. A more elucidative picture of the molecular mechanism of digestion in a scorpion was proposed based on our results from Tityus serrulatus. The midgut and midgut glands (MMG) are composed by secretory and digestive cells. In fasting animals, the secretory granules are ready for the next predation event, containing enzymes needed for alkaline extra-oral digestion which will compose the digestive fluid, such as trypsins, astacins and chitinase. The digestive vacuoles are filled with an acidic proteolytic cocktail to the intracellular digestion composed by cathepsins L, B, F, D and legumain. Other proteins as lipases, carbohydrases, ctenitoxins and a chitolectin with a perithrophin domain were also detected. Evolutionarily

  1. Internalization of exogenous cystatin F supresses cysteine proteases and induces the accumulation of single-chain cathepsin L by multiple mechanisms.

    Science.gov (United States)

    Colbert, Jeff D; Matthews, Stephen P; Kos, Janko; Watts, Colin

    2011-12-01

    Cystatin F is an unusual member of the cystatin family of protease inhibitors, which is made as an inactive dimer and becomes activated by proteolysis in the endo/lysosome pathway of the immune cells that produce it. However a proportion is secreted and can be taken up and activated by other cells. We show here that cystatin F acquired in this way induces a dramatic accumulation of the single-chain form of cathepsin L (CatL). Cystatin F was observed in the same cellular compartments as CatL and was tightly complexed with CatL as determined by co-precipitation studies. The observed accumulation of single-chain CatL was partly due to cystatin F-mediated inhibition of the putative single-chain to two-chain CatL convertase AEP/legumain and partly to general suppression of cathepsin activity. Thus, cystatin F stabilizes CatL leading to the dramatic accumulation of an inactive complex composed either of the single-chain or two-chain form depending on the capacity of cystatin F to inhibit AEP. Cross-transfer of cystatin F from one cell to another may therefore attenuate potentially harmful effects of excessive CatL activity while paradoxically, inducing accumulation of CatL protein. Finally, we confirmed earlier data (Beers, C., Honey, K., Fink, S., Forbush, K., and Rudensky, A. (2003) J. Exp. Med. 197, 169-179) showing a loss of CatL activity, but not of CatL protein, in macrophages activated with IFNγ. However, we found equivalent loss of CatL activity in wild type and cystatin F-null macrophages suggesting that an inhibitory activity other than cystatin F quenches CatL activity in activated macrophages.

  2. Characterization of the entire cystatin gene family in barley and their target cathepsin L-like cysteine-proteases, partners in the hordein mobilization during seed germination.

    Science.gov (United States)

    Martinez, Manuel; Cambra, Ines; Carrillo, Laura; Diaz-Mendoza, Mercedes; Diaz, Isabel

    2009-11-01

    Plant cystatins are inhibitors of cysteine-proteases of the papain C1A and legumain C13 families. Cystatin data from multiple plant species have suggested that these inhibitors act as defense proteins against pests and pathogens and as regulators of protein turnover. In this study, we characterize the entire cystatin gene family from barley (Hordeum vulgare), which contain 13 nonredundant genes, and identify and characterize their target enzymes, the barley cathepsin L-like proteases. Cystatins and proteases were expressed and purified from Escherichia coli cultures. Each cystatin was found to have different inhibitory capability against barley cysteine-proteases in in vitro inhibitory assays using specific substrates. Real-time reverse transcription-polymerase chain reaction revealed that inhibitors and enzymes present a wide variation in their messenger RNA expression patterns. Their transcripts were mainly detected in developing and germinating seeds, and some of them were also expressed in leaves and roots. Subcellular localization of cystatins and cathepsin L-like proteases fused to green fluorescent protein demonstrated the presence of both protein families throughout the endoplasmic reticulum and the Golgi complex. Proteases and cystatins not only colocalized but also interacted in vivo in the plant cell, as revealed by bimolecular fluorescence complementation. The functional relationship between cystatins and cathepsin L-like proteases was inferred from their common implication as counterparts of mobilization of storage proteins upon barley seed germination. The opposite pattern of transcription expression in gibberellin-treated aleurones presented by inhibitors and enzymes allowed proteases to specifically degrade B, C, and D hordeins stored in the endosperm of barley seeds.

  3. The role of cystatins in tick physiology and blood feeding.

    Science.gov (United States)

    Schwarz, Alexandra; Valdés, James J; Kotsyfakis, Michalis

    2012-06-01

    Ticks, as obligate hematophagous ectoparasites, impact greatly on animal and human health because they transmit various pathogens worldwide. Over the last decade, several cystatins from different hard and soft ticks were identified and biochemically analyzed for their role in the physiology and blood feeding lifestyle of ticks. All these cystatins are potent inhibitors of papain-like cysteine proteases, but not of legumain. Tick cystatins were either detected in the salivary glands and/or the midgut, key tick organs responsible for blood digestion and the expression of pharmacologically potent salivary proteins for blood feeding. For example, the transcription of two cystatins named HlSC-1 and Sialostatin L2 was highly upregulated in these tick tissues during feeding. Vaccinating hosts against Sialostatin L2 and Om-cystatin 2 as well as silencing of a cystatin gene from Amblyomma americanum significantly inhibited the feeding ability of ticks. Additionally, Om-cystatin 2 and Sialostatin L possessed strong host immunosuppressive properties by inhibiting dendritic cell maturation due to their interaction with cathepsin S. These two cystatins, together with Sialostatin L2 are the first tick cystatins with resolved three-dimensional structure. Sialostatin L, furthermore, showed preventive properties against autoimmune diseases. In the case of the cystatin Hlcyst-2, experimental evidence showed its role in tick innate immunity, since increased Hlcyst-2 transcript levels were detected in Babesia gibsoni-infected larval ticks and the protein inhibited Babesia growth. Other cystatins, such as Hlcyst-1 or Om-cystatin 2 are assumed to be involved in regulating blood digestion. Only for Bmcystatin was a role in tick embryogenesis suggested. Finally, all the biochemically analyzed tick cystatins are powerful protease inhibitors, and some may be novel antigens for developing anti-tick vaccines and drugs of medical importance due to their stringent target specificity.

  4. Systems level analysis and identification of pathways and networks associated with liver fibrosis.

    Directory of Open Access Journals (Sweden)

    Mohamed Diwan M AbdulHameed

    Full Text Available Toxic liver injury causes necrosis and fibrosis, which may lead to cirrhosis and liver failure. Despite recent progress in understanding the mechanism of liver fibrosis, our knowledge of the molecular-level details of this disease is still incomplete. The elucidation of networks and pathways associated with liver fibrosis can provide insight into the underlying molecular mechanisms of the disease, as well as identify potential diagnostic or prognostic biomarkers. Towards this end, we analyzed rat gene expression data from a range of chemical exposures that produced observable periportal liver fibrosis as documented in DrugMatrix, a publicly available toxicogenomics database. We identified genes relevant to liver fibrosis using standard differential expression and co-expression analyses, and then used these genes in pathway enrichment and protein-protein interaction (PPI network analyses. We identified a PPI network module associated with liver fibrosis that includes known liver fibrosis-relevant genes, such as tissue inhibitor of metalloproteinase-1, galectin-3, connective tissue growth factor, and lipocalin-2. We also identified several new genes, such as perilipin-3, legumain, and myocilin, which were associated with liver fibrosis. We further analyzed the expression pattern of the genes in the PPI network module across a wide range of 640 chemical exposure conditions in DrugMatrix and identified early indications of liver fibrosis for carbon tetrachloride and lipopolysaccharide exposures. Although it is well known that carbon tetrachloride and lipopolysaccharide can cause liver fibrosis, our network analysis was able to link these compounds to potential fibrotic damage before histopathological changes associated with liver fibrosis appeared. These results demonstrated that our approach is capable of identifying early-stage indicators of liver fibrosis and underscore its potential to aid in predictive toxicity, biomarker identification, and to

  5. Systems Level Analysis and Identification of Pathways and Networks Associated with Liver Fibrosis

    Science.gov (United States)

    AbdulHameed, Mohamed Diwan M.; Tawa, Gregory J.; Kumar, Kamal; Ippolito, Danielle L.; Lewis, John A.; Stallings, Jonathan D.; Wallqvist, Anders

    2014-01-01

    Toxic liver injury causes necrosis and fibrosis, which may lead to cirrhosis and liver failure. Despite recent progress in understanding the mechanism of liver fibrosis, our knowledge of the molecular-level details of this disease is still incomplete. The elucidation of networks and pathways associated with liver fibrosis can provide insight into the underlying molecular mechanisms of the disease, as well as identify potential diagnostic or prognostic biomarkers. Towards this end, we analyzed rat gene expression data from a range of chemical exposures that produced observable periportal liver fibrosis as documented in DrugMatrix, a publicly available toxicogenomics database. We identified genes relevant to liver fibrosis using standard differential expression and co-expression analyses, and then used these genes in pathway enrichment and protein-protein interaction (PPI) network analyses. We identified a PPI network module associated with liver fibrosis that includes known liver fibrosis-relevant genes, such as tissue inhibitor of metalloproteinase-1, galectin-3, connective tissue growth factor, and lipocalin-2. We also identified several new genes, such as perilipin-3, legumain, and myocilin, which were associated with liver fibrosis. We further analyzed the expression pattern of the genes in the PPI network module across a wide range of 640 chemical exposure conditions in DrugMatrix and identified early indications of liver fibrosis for carbon tetrachloride and lipopolysaccharide exposures. Although it is well known that carbon tetrachloride and lipopolysaccharide can cause liver fibrosis, our network analysis was able to link these compounds to potential fibrotic damage before histopathological changes associated with liver fibrosis appeared. These results demonstrated that our approach is capable of identifying early-stage indicators of liver fibrosis and underscore its potential to aid in predictive toxicity, biomarker identification, and to generally identify

  6. Trichocystatin-2 (TC-2): an endogenous inhibitor of cysteine proteinases in Trichomonas vaginalis is associated with TvCP39.

    Science.gov (United States)

    Puente-Rivera, Jonathan; Ramón-Luing, Lucero de los Ángeles; Figueroa-Angulo, Elisa Elvira; Ortega-López, Jaime; Arroyo, Rossana

    2014-09-01

    The causal agent of trichomoniasis is a parasitic protist, Trichomonas vaginalis, which is rich in proteolytic activity, primarily carried out by cysteine proteases (CPs). Some CPs are known virulence factors. T. vaginalis also possesses three genes encoding endogenous cystatin-like CP inhibitors. The aim of this study was to identify and characterize one of these CP inhibitors. Using two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS), a cystatin-like peptidase inhibitor dubbed Trichocystatin-2 (TC-2) was identified in the T. vaginalis active degradome in association with TvCP39, a 39kDa CP involved in cytotoxicity. To characterize the TC-2 inhibitor, we cloned and expressed the tvicp-2 gene, purified the recombinant protein (TC-2r), and produced a specific polyclonal antibody (α-TC-2r). This antibody recognized a 10kDa protein band by western blotting. An indirect immunofluorescence assay (IFA) and cell fractionation assays using the α-TC-2r antibody showed that TC-2 was localized in the cytoplasm and lysosomes and that it colocalized with TvCP39. TC-2r showed inhibitory activity against papain, cathepsin-L, and TvCP39 in trichomonad extracts and live parasites but not legumain-like CPs. Live trichomonads treated with TC-2r showed reduced trichomonal cytotoxicity to HeLa cell monolayers in a TC-2r-concentration-dependent manner. In this study, we identified and characterized an endogenous cystatin-like inhibitor in T. vaginalis, TC-2, which is associated with TvCP39 and appears to regulate the cellular damage caused by T. vaginalis.

  7. Biochemical, transcriptomic and proteomic analyses of digestion in the scorpion Tityus serrulatus: insights into function and evolution of digestion in an ancient arthropod.

    Directory of Open Access Journals (Sweden)

    Felipe J Fuzita

    Full Text Available Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challenge. Understanding the physiology of scorpions can not only lead to evolutionary insights but also is a crucial step in the development of control strategies. However, the digestive process in scorpions has been scarcely studied. In this work, we describe the combinatory use of next generation sequencing, proteomic analysis and biochemical assays in order to investigate the digestive process in the yellow scorpion Tityus serrulatus, mainly focusing in the initial protein digestion. The transcriptome generated database allowed the quantitative identification by mass spectrometry of different enzymes and proteins involved in digestion. All the results suggested that cysteine cathepsins play an important role in protein digestion. Two digestive cysteine cathepsins were isolated and characterized presenting acidic characteristics (pH optima and stability, zymogen conversion to the mature form after acidic activation and a cross-class inhibition by pepstatin. A more elucidative picture of the molecular mechanism of digestion in a scorpion was proposed based on our results from Tityus serrulatus. The midgut and midgut glands (MMG are composed by secretory and digestive cells. In fasting animals, the secretory granules are ready for the next predation event, containing enzymes needed for alkaline extra-oral digestion which will compose the digestive fluid, such as trypsins, astacins and chitinase. The digestive vacuoles are filled with an acidic proteolytic cocktail to the intracellular digestion composed by cathepsins L, B, F, D and legumain. Other proteins as lipases, carbohydrases, ctenitoxins and a chitolectin with a perithrophin domain were also

  8. Localization of two human autoantigen genes by PCR screening and in situ hybridization-glycyl-tRNA synthetase locates to 7p15 and Alanyl-tRNA synthetase locates to 16q22

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, R.C.; Pai, S.I.; Liu, P. [National Inst. of Health, Bethesda, MD (United States); Ge, Q.; Targoff, I.N. [Oklahoma Medical Research Foundation, Oklahoma City, OK (United States)

    1995-11-01

    Aminoacyl-tRNA synthetases (aminoacyl-RS) catalyze the attachment of an amino acid to its cognate tRNA. Five of 20 human aminoacyl-RS (histidyl-RS, threonyl-RS, isoleucyl-RS, glycyl-RS, and alanyl-RS) have been identified as targets of autoantibodies in the autoimmune disease polymyositis/dermatomyositis (PM/DM; 9). A sixth autoantigenic amino-acyl-RS, lysyl-RS, was recently reported. The genes for histidyl-RS and threonyl-RS have been assigned to chromosome 5, as have the genes for leucyl-RS and arginyl-RS. Six other aminoacyl-RS (glutamyl-prolyl-RS, valyl-RS, cysteinyl-RS, methionyl-RS, tryptophanyl-RS, and asparaginyl-RS) were assigned to chromosomes 1, 6, 11, 12, 14, and 18, respectively. The reason for a preponderance of aminoacyl-RS genes on chromosome 5 is unknown, but it has been suggested that regulatory relatedness might be a factor. Recently the entire or partial cDNA sequences for two autoantigenic aminoacyl-RS genes, glycyl-RS (gene symbol GARS; 4) and alanyl-RS (gene symbol AARS; 1), were reported. To understand further the genesis of autoimmune responses to aminoacyl-RS and to determine whether genes for autoantigenic aminoacyl-RS colocalize to chromosome 5, we have determined the chromosomal site of the GARS and AARS genes by PCR-based screening of somatic cell hybrid panels and by fluorescence in situ hybridization (FISH) analysis. 10 refs., 1 fig.

  9. The genome of Pelobacter carbinolicus reveals surprising metabolic capabilities and physiological features

    Directory of Open Access Journals (Sweden)

    Aklujkar Muktak

    2012-12-01

    Full Text Available Abstract Background The bacterium Pelobacter carbinolicus is able to grow by fermentation, syntrophic hydrogen/formate transfer, or electron transfer to sulfur from short-chain alcohols, hydrogen or formate; it does not oxidize acetate and is not known to ferment any sugars or grow autotrophically. The genome of P. carbinolicus was sequenced in order to understand its metabolic capabilities and physiological features in comparison with its relatives, acetate-oxidizing Geobacter species. Results Pathways were predicted for catabolism of known substrates: 2,3-butanediol, acetoin, glycerol, 1,2-ethanediol, ethanolamine, choline and ethanol. Multiple isozymes of 2,3-butanediol dehydrogenase, ATP synthase and [FeFe]-hydrogenase were differentiated and assigned roles according to their structural properties and genomic contexts. The absence of asparagine synthetase and the presence of a mutant tRNA for asparagine encoded among RNA-active enzymes suggest that P. carbinolicus may make asparaginyl-tRNA in a novel way. Catabolic glutamate dehydrogenases were discovered, implying that the tricarboxylic acid (TCA cycle can function catabolically. A phosphotransferase system for uptake of sugars was discovered, along with enzymes that function in 2,3-butanediol production. Pyruvate:ferredoxin/flavodoxin oxidoreductase was identified as a potential bottleneck in both the supply of oxaloacetate for oxidation of acetate by the TCA cycle and the connection of glycolysis to production of ethanol. The P. carbinolicus genome was found to encode autotransporters and various appendages, including three proteins with similarity to the geopilin of electroconductive nanowires. Conclusions Several surprising metabolic capabilities and physiological features were predicted from the genome of P. carbinolicus, suggesting that it is more versatile than anticipated.

  10. Tryptophan and Cysteine Oxidation Products Dominate in α-Lactalbumin-Derived Peptides Analyzed with LC-MS(n).

    Science.gov (United States)

    Koivumäki, Tuuli P; Gürbüz, Göker; Heinonen, I Marina

    2017-09-01

    α-Lactalbumin (α-La), a major milk whey protein, is comprised of several amino acids prone to metal-catalyzed oxidation (MCO) typical in processing and during storage of foods. New tools are needed for the detection of characteristic oxidation products especially from tryptophan and cysteine that often remain unrecognized when using the traditional methods of carbonyl formation monitoring. In this study, the oxidative changes in α-La were investigated through tryptic digestion and collection of 3 descriptive peptides fitted into a metal-catalyzed oxidation (Fenton reaction) model. The peptide samples were oxidized at +37 °C for 14 d and explored with liquid chromatography-quadrupole ion trap-mass spectrometer (LC-MS(n) ). The fractionated α-La peptides were valyl-glycyl-isoleucyl-asparaginyl-tyrosyl-tryptophyl-leucyl-alanyl-histidyl-lysine (VGINYWLAHK), leucyl-aspartyl-glutaminyl-tryptophyl-leucyl-cysteinyl-glutamyl-lysine (LDQWLCEK), and tryptophyl(+16) -leucyl-alanyl-histidyl-lysyl-alanyl-leucyl-cysteine (W(+16) LAHKALC). Oxidation of several amino acids, such as cysteine, histidine, lysine, and tryptophan was observed. In the peptide LDQWLCEK, cysteine was rapidly trioxidized to sulfonic acid, followed by other amino acid side chains as secondary oxidation sites. Tryptophan oxidation was more pronounced in the peptides W(+16) LAHKALC and VGINYWLAHK, and also formation of the harmful N-formylkynurenine was observed. As a conclusion, several stable and promising oxidation markers are proposed for α-La, which could be implemented in the evaluation of quality and safety of dairy protein-containing products. © 2017 Institute of Food Technologists®.

  11. Synthesis of Fluorescent Gelators and Direct Observation of Gelation with a Fluorescence Microscope.

    Science.gov (United States)

    Hanabusa, Kenji; Ueda, Takuya; Takata, Shingo; Suzuki, Masahiro

    2016-11-14

    Fluorescein-, benzothiazole-, quinoline-, stilbene-, and carbazole-containing fluorescent gelators have been synthesized by connecting gelation-driving segments, including l-isoleucine, l-valine, l-phenylalanine, l-leucine residue, cyclo(l-asparaginyl-l-phenylalanyl), and trans-(1R,2R)-diaminocyclohexane. The emission behaviors of the gelators were investigated, and their gelation abilities studied against 15 solvents. The minimum gel concentration, variable-temperature spectroscopy, transmission electron microscopy, scanning electron microscopy, fluorescence microscopy (FM), and confocal laser scanning microscopy (CLSM) were used to characterize gelation. The intermolecular hydrogen bonding between the N-H and C=O of amide, van der Waals interactions and π-π stacking play important roles in gelation. The colors of emission are related to the fluorescence structures of gelators. Fibrous aggregates characterized by the color of their emission were observed by FM. 3D images are produced by the superposition of images captured by CLSM every 0.1 μm to a settled depth. The 3D images show that the large micrometer-sized aggregates spread out three dimensionally. FM observations of mixed gelators are studied. In the case of gelation, two structurally related gelators with the same gelation-driving segment lead to the gelators build up of the same aggregates through similar hydrogen-bonding patterns. When two gelators with structurally different gelation-driving segments induce gelation, the gelators build up each aggregate through individual hydrogen-bonding patterns. A fluorescent reagent that was incorporated into the aggregates of gels through van der Waals interactions was developed. The addition of this fluorescent reagent enables the successful observation of nonfluorescent gelators' aggregates by FM.

  12. The interplay between protein L-isoaspartyl methyltransferase activity and insulin-like signaling to extend lifespan in Caenorhabditis elegans.

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    Shilpi Khare

    Full Text Available The protein L-isoaspartyl-O-methyltransferase functions to initiate the repair of isomerized aspartyl and asparaginyl residues that spontaneously accumulate with age in a variety of organisms. Caenorhabditis elegans nematodes lacking the pcm-1 gene encoding this enzyme display a normal lifespan and phenotype under standard laboratory growth conditions. However, significant defects in development, egg laying, dauer survival, and autophagy have been observed in pcm-1 mutant nematodes when deprived of food and when exposed to oxidative stress. Interestingly, overexpression of this repair enzyme in both Drosophila and C. elegans extends adult lifespan under thermal stress. In this work, we show the involvement of the insulin/insulin-like growth factor-1 signaling (IIS pathway in PCM-1-dependent lifespan extension in C. elegans. We demonstrate that reducing the levels of the DAF-16 downstream transcriptional effector of the IIS pathway by RNA interference reduces the lifespan extension resulting from PCM-1 overexpression. Using quantitative real-time PCR analysis, we show the up-regulation of DAF-16-dependent stress response genes in the PCM-1 overexpressor animals compared to wild-type and pcm-1 mutant nematodes under mild thermal stress conditions. Additionally, similar to other long-lived C. elegans mutants in the IIS pathway, including daf-2 and age-1 mutants, PCM-1 overexpressor adult animals display increased resistance to severe thermal stress, whereas pcm-1 mutant animals survive less long under these conditions. Although we observe a higher accumulation of damaged proteins in pcm-1 mutant nematodes, the basal level of isoaspartyl residues detected in wild-type animals was not reduced by PCM-1 overexpression. Our results support a signaling role for the protein L-isoaspartyl methyltransferase in lifespan extension that involves the IIS pathway, but that may be independent of its function in overall protein repair.

  13. Inhibition of hypoxia-inducible factor (HIF) hydroxylases by citric acid cycle intermediates: possible links between cell metabolism and stabilization of HIF.

    Science.gov (United States)

    Koivunen, Peppi; Hirsilä, Maija; Remes, Anne M; Hassinen, Ilmo E; Kivirikko, Kari I; Myllyharju, Johanna

    2007-02-16

    The stability and transcriptional activity of the hypoxia-inducible factors (HIFs) are regulated by two oxygen-dependent events that are catalyzed by three HIF prolyl 4-hydroxylases (HIF-P4Hs) and one HIF asparaginyl hydroxylase (FIH). We have studied possible links between metabolic pathways and HIF hydroxylases by analyzing the abilities of citric acid cycle intermediates to inhibit purified human HIF-P4Hs and FIH. Fumarate and succinate were identified as in vitro inhibitors of all three HIF-P4Hs, fumarate having K(i) values of 50-80 microM and succinate 350-460 microM, whereas neither inhibited FIH. Oxaloacetate was an additional inhibitor of all three HIF-P4Hs with K(i) values of 400-1000 microM and citrate of HIF-P4H-3, citrate being the most effective inhibitor of FIH with a K(i) of 110 microM. Culturing of cells with fumarate diethyl or dimethyl ester, or a high concentration of monoethyl ester, stabilized HIF-1alpha and increased production of vascular endothelial growth factor and erythropoietin. Similar, although much smaller, changes were found in cultured fibroblasts from a patient with fumarate hydratase (FH) deficiency and upon silencing FH using small interfering RNA. No such effects were seen upon culturing of cells with succinate diethyl or dimethyl ester. As FIH was not inhibited by fumarate, our data indicate that the transcriptional activity of HIF is quite high even when binding of the coactivator p300 is prevented. Our data also support recent suggestions that the increased fumarate and succinate levels present in the FH and succinate dehydrogenase-deficient tumors, respectively, can inhibit the HIF-P4Hs with consequent stabilization of HIF-alphas and effects on tumor pathology.

  14. Role of Endoproteolytic Dibasic Proprotein Processing in Maturation of Secretory Proteins in Trichoderma reesei

    Science.gov (United States)

    Goller, Sabine P.; Schoisswohl, Doris; Baron, Michel; Parriche, Martine; Kubicek, Christian P.

    1998-01-01

    Cell extracts of Trichoderma reesei exhibited dibasic endopeptidase activity toward the carboxylic side of KR, RR, and PR sequences. This activity was stimulated by the presence of Ca2+ ions and localized in vesicles of low bouyant density; it therefore exhibited some similarity to yeast Kex2. Analytical chromatofocusing revealed a single peak of activity. The dibasic endopeptidase activity was strongly and irreversibly inhibited in vitro as well as in vivo by 1 mM p-amidinophenylmethylsulfonyl fluoride (pAPMSF) but not by PMSF at concentrations up to 5 mM. We therefore used pAPMSF to study the role of the dibasic endopeptidase in the secretion of protein by T. reesei. Secretion of xylanase I (proprotein processing sequence -R-R-↓-R-↓-A-) and xylanase II (-K-R-↓-Q-) was strongly inhibited by 1 mM pAPMSF, and a larger, unprocessed enzyme form was detected intracellularly under these conditions. Secretion of cellobiohydrolase II (CBH II; -E-R-↓-Q-) was only slightly inhibited by pAPMSF, and no accumulation of unprocessed precursors was detected. In contrast, secretion of CBH I (-R-A-↓-Q-) was stimulated by pAPMSF addition, and a simultaneous decrease in the concentration of intracellular CBH I was detected. Similar experiments were also carried out with a single heterologous protein, ShBLE, the phleomycin-binding protein from Streptoalloteichus hindustanus, fused to a series of model proprotein-processing sequences downstream of the expression signals of the Aspergillus nidulans gpdA promoter. Consistent with the results obtained with homologous proteins, pAPMSF inhibited the secretion of ShBLE with fusions containing dibasic (RK and KR) target sequences, but it even stimulated secretion in fusions to LR, NHA, and EHA target sequences. Addition of 5 mM PMSF, a nonspecific inhibitor of serine protease, nonspecifically inhibited the secretion of heterologous proteins from fusions bearing the NHA and LR targets. These data point to the existence of different

  15. Elastinolytic and proteolytic enzymes.

    Science.gov (United States)

    Kessler, Efrat; Safrin, Mary

    2014-01-01

    Pseudomonas aeruginosa secretes into its environment at least seven extracellular proteases: pseudolysin (LasB protease; elastase), aeruginolysin (alkaline proteinase), staphylolysin (staphylolytic endopeptidase; LasA protease), lysyl endopeptidase (protease IV; PrpL), PASP (P. aeruginosa small protease), LepA (Large ExoProtease A), and an aminopeptidase. Their action on host proteins, both individually and synergistically, plays important roles in pathogenesis of P. aeruginosa infections. Methods to measure/detect their activities are fundamental for understanding their physiological functions, roles in pathogenesis, mechanisms of action, regulation, and secretion. Most assays for determination/detection of proteolytic activity employ modified/non-modified casein or gelatin as substrates. In the quantitative assay, fragments generated from azocasein are separated from undigested substrate by trichloroacetic acid precipitation and their absorbance is measured. In non-quantitative assays, proteolytic activity is detected as clearing zones around bacterial growth or samples of culture supernatants on casein containing solid media formed due to local casein degradation. In zymography, individual proteases are detected as clear bands in gelatin/casein containing gels after SDS-PAGE separation, renaturation and protein staining. The elastinolytic capacity of P. aeruginosa is reflected by clearing zones on nutrient agar plates containing insoluble elastin instead of casein. Mueller-Hinton agar plates on which S. aureus cells are grown as a lawn are used to assess the susceptibility of S. aureus isolates to staphylolysin. A clear zone around a staphylolysin-containing sample indicates inhibition of S. aureus growth. Methods for measuring the activity of individual proteases are based on their cleavage specificity. These include assays of elastinolytic activity of pseudolysin and/or staphylolysin using elastin-Congo red as a substrate, a method for determination of

  16. Inhibitory effect of the carnosine-gallic acid synthetic peptide on MMP-2 and MMP-9 in human fibrosarcoma HT1080 cells.

    Science.gov (United States)

    Kim, Sung-Rae; Eom, Tae-Kil; Byun, Hee-Guk

    2014-09-01

    Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that degrade extracellular matrix components and play important roles in a variety of biological and pathological processes such as malignant tumor metastasis and invasion. In this study, we constructed carnosine-gallic acid peptide (CGP) to identify a better MMP inhibitor than carnosine. The inhibitory effects of CGP on MMP-2 and MMP-9 were investigated in the human fibrosarcoma (HT1080) cell line. As a result, CGP significantly decreased MMP-2 and MMP-9 expression levels without a cytotoxic effect. Moreover, CGP may inhibit migration and invasion in HT1080 cells through the urokinase plasminogen activator (uPA)-uPA receptor signaling pathways to inhibit MMP-2 and MMP-9. Based on these results, it appears that CGP may play an important role in preventing and treating several MMP-2 and MMP-9-mediated health problems such as metastasis.

  17. Purification and characterization of neurotoxin complex from a dual toxin gene containing Clostridium Botulinum Strain PS-5.

    Science.gov (United States)

    Singh, Ajay K; Sachdeva, Amita; Degrasse, Jeffrey A; Croley, Timothy R; Stanker, Larry H; Hodge, David; Sharma, Shashi K

    2013-04-01

    Botulinum neurotoxins are produced as a toxin complex (TC) which consists of neurotoxin (NT) and neurotoxin associated proteins. The characterization of NT in its native state is an essential step for developing diagnostics and therapeutic countermeasures against botulism. The presence of NT genes was validated by PCR amplification of toxin specific fragments from genomic DNA of Clostridium botulinum strain PS-5 which indicated the presence of both serotype A and B genes on PS-5 genome. Further, TC was purified and characterized by Western blotting, Digoxin-enzyme linked immunosorbent assay, endopeptidase activity assay, and Liquid chromatography-Mass spectrometry. The data showed the presence of serotype A specific neurotoxin. Based on the analysis of neurotoxin genes and characterization of TC, PS-5 strain appears as a serotype A (B) strain of C. botulinum which produces only serotype A specific TC in the cell culture medium.

  18. VAMP/synaptobrevin cleavage by tetanus and botulinum neurotoxins is strongly enhanced by acidic liposomes.

    Science.gov (United States)

    Caccin, Paola; Rossetto, Ornella; Rigoni, Michela; Johnson, Eric; Schiavo, Giampietro; Montecucco, Cesare

    2003-05-01

    Tetanus and botulinum neurotoxins (TeNT and BoNTs) block neuroexocytosis via specific cleavage and inactivation of SNARE proteins. Such activity is exerted by the N-terminal 50 kDa light chain (L) domain, which is a zinc-dependent endopeptidase. TeNT, BoNT/B, /D, /F and /G cleave vesicle associated membrane protein (VAMP), a protein of the neurotransmitter-containing small synaptic vesicles, at different single peptide bonds. Since the proteolytic activity of these metalloproteases is higher on native VAMP inserted in synaptic vesicles than on recombinant VAMP, we have investigated the influence of liposomes of different lipid composition on this activity. We found that the rate of VAMP cleavage with all neurotoxins tested here is strongly enhanced by negatively charged lipid mixtures. This effect is at least partially due to the binding of the metalloprotease to the lipid membranes, with electrostatic interactions playing an important role.

  19. Structural Studies of Matrix Metalloproteinase by X-Ray Diffraction.

    Science.gov (United States)

    Decaneto, Elena; Lubitz, Wolfgang; Ogata, Hideaki

    2017-01-01

    Matrix Metalloproteinases (MMPs) are a family of proteolytic enzymes whose endopeptidase activity is dependent on the presence of specific metal ions. MT1-MMP (or MMP-14), which has been implicated in tumor progression and cellular invasion, contains a membrane-spanning region located C-terminal to a hemopexin-like domain and an N-terminal catalytic domain. We recombinantly expressed the catalytic domain of human MT1-MMP in E. coli and purified it from inclusion bodies using a refolding protocol that yielded significant quantities of active protein. Crystals of MT1-MMP were obtained using the vapour diffusion method. Here, we describe the protocols used for crystallization and the data analysis together with the resulting diffraction pattern.

  20. Proteolytic properties of Funastrum clausum latex.

    Science.gov (United States)

    Morcelle, Susana R; Caffini, Néstor O; Priolo, Nora

    2004-07-01

    As part of a screening of latex endopeptidases from plants growing in Argentina, the presence of proteolytic activity in the latex of Funastrum clausum stems is reported. The proteases present in the crude extract showed the main characteristics of the cysteine proteolytic class, i.e. optimum pH at alkaline range, isoelectric point (pI) higher than 9.0, and inhibition of proteolytic activity by thiol blocking reagents. A remarkable thermal stability was also evident in the crude extract. Endosterolytic preference tried on p-nitrophenyl esters of N-alpha-carbobenzoxy-L-amino acids was higher for the alanine, asparagine and tyrosine derivatives. Preliminary peptidase purification by two-step ionic exchange showed the presence of two proteolytic fractions with molecular masses of approximately 24.0 kDa according to SDS-PAGE.

  1. Characterization of the proteases in the midgut of the xylophagous larvae of Oemona hirta (Coleoptera:Cerambycidae)

    Institute of Scientific and Technical Information of China (English)

    Brian David Shaw; John Tane Christeller

    2009-01-01

    The protein digestive capability oftbe larvae of the longhorn beetle (Oemona hirta,Coleoptera:Cerambycidae,Fabricius,1775) was investigated.This species feeds only on wood where there is a high proportion of vascular tissue.The pH of the midgut,the major digestive organ,was alkaline and protein hydrolysis was maximal at alkaline pH.Use of specific synthetic peptide substrates showed that the major protease activities were the endopeptidases,trypsin and chymotrypsin-like activity,and the exopeptidase,leucine aminopeptidase and the pH curves corresponded to that with protein substrate.Studies using a range ofsefine protease inhibitors as well as specific inhibitors ofmetalloproteases,cysteine proteases and aspartate proteases confirmed a serine protease-based digestive system similar to earlier reports of sapwood-feeding Cerambycids.Control of these insect pests using protease inhibitors is discussed.

  2. Cathepsins mediate tumor metastasis

    Institute of Scientific and Technical Information of China (English)

    Gong-Jun; Tan; Zheng-Ke; Peng; Jin-Ping; Lu; Fa-Qing; Tang

    2013-01-01

    Cathepsins are highly expressed in various human cancers, associated with tumor metastasis. It is superfamily, concluding A, B, C, D, E, F, G, H, L, K, O, S, V, and W family members. As a group of lysosomal proteinases or endopeptidases, each member has a different function, playing different roles in distinct tumorigenic processes such as proliferation, angiogenesis, metastasis, and invasion. Cathepsins belong to a diverse number of enzyme subtypes, including cysteine proteases, serine proteases and aspartic proteases. The contribution of cathepsins to invasion in human cancers is well documented, although the precise mechanisms by which cathepsins exert their effects are still not clear. In the present review, the role of cathepsin family members in cancer is discussed.

  3. A peptidomic approach to study the contribution of added casein proteins to the peptide profile in Spanish dry-fermented sausages.

    Science.gov (United States)

    Mora, Leticia; Escudero, Elizabeth; Aristoy, M-Concepción; Toldrá, Fidel

    2015-11-06

    Peptidomics is a necessary alternative in the analysis of naturally generated peptides in dry-fermented processing. The intense proteolysis occurred during the processing of dry-fermented sausages is due to the action of endopeptidases and exopeptidases from both, endogenous muscle origin and lactic acid bacteria (LAB) added in the starter. Sodium caseinate is frequently used as an additive in this type of products because of its emulsifying properties, and consequently influences the protein profile available during the proteolysis. In this study, a mass spectrometry approach has been used to determine the impact of added sodium caseinate in the final peptide profile as well as to analyse its possible influence in the presence of certain previously described casein-derived bioactive peptides.

  4. Expression and Efficient One-Step Chromatographic Purification of a Soluble Antagonist for Human Leukemia Inhibitory Factor Receptor in Escherichia coli.

    Science.gov (United States)

    Kim, Eun-Yeong; Choi, Hee-Jung; Chung, Tae-Wook; Jang, Se Bok; Kim, Kibong; Ha, Ki-Tae

    2015-08-01

    Leukemia inhibitory factor (LIF) is a member of the IL-6 cytokine family, having pleiotropic actions such as maintaining stem cell pluripotency and enabling blastocyst implantation. Because the action of LIF is mediated by a ligand-receptor interaction with the LIF receptor (LIF-R), an antagonist for LIF-R has been developed to inhibit LIF-induced signaling. In this study, we present a novel method for the production and purification of an antagonist to human LIF-R (hLA). His-tagged hLA was expressed in E. coli, and simple purification methods without any endopeptidase cleavage were designed. In addition, we determined the optimal temperature conditions for enhancing the production of soluble hLA. Finally, the bioactivity of His-tagged hLA was examined using STAT3 phosphorylation and receptivity of human endometrial ECC-1 cells. Our strategy provides a rapid and efficient method to produce biologically active recombinant hLA.

  5. Tobacco Etch Virus protease: A shortcut across biotechnologies.

    Science.gov (United States)

    Cesaratto, Francesca; Burrone, Oscar R; Petris, Gianluca

    2016-08-10

    About thirty years ago, studies on the RNA genome of Tobacco Etch Virus revealed the presence of an efficient and specific protease, called Tobacco Etch Virus protease (TEVp), that was part of the Nuclear Inclusion a (NIa) enzyme. TEVp is an efficient and specific protease of 27kDa that has become a valuable biotechnological tool. Nowadays TEVp is a unique endopeptidase largely exploited in biotechnology from industrial applications to in vitro and in vivo cellular studies. A number of TEVp mutants with different rate of cleavage, stability and specificity have been reported. Similarly, a panel of different target cleavage sites, derived from the canonical ENLYFQ-G/S site, has been established. In this review we describe these aspects of TEVp and some of its multiple applications. A particular focus is on the use and molecular biology of TEVp in living cells and organisms.

  6. [Matrix metalloproteases as molecular markers in gastric cancer].

    Science.gov (United States)

    de la Peña, Sol; Sampieri, Clara L; León-Córdoba, Kenneth

    2010-02-06

    Gastric cancer is the second leading cause of cancer-associated mortality in the world. Prognosis in patients with gastric cancer is difficult to establish because it is commonly diagnosed when gastric wall invasion and metastasis have occurred. Currently, some members of the extracellular matrix metalloproteinases have been identified, whose expression in gastric tumor tissue is significantly elevated compared to healthy gastric tissue. Matrix metalloproteinases are 24 zinc-dependent endopeptidases that catalyze the proteolysis of the extracellular matrix. This degradation allows the cancer cells invade the surrounding stroma and trigger metastasis. Upregulation of certain matrix metalloproteinases in gastric cancer has been associated with a poor prognosis and elevated invasive capacity. This review compiles evidence about the genetic expression of matrix metalloproteinases in gastric cancer and their role in tumour invasion and metastasis, emphasizing their potential as molecular markers of prognosis. Copyright 2009 Elsevier España, S.L. All rights reserved.

  7. Trichomonas tenax proteolytic activity.

    Science.gov (United States)

    Segović, S; Buntak-Kobler, D; Galić, N; Katunarić, M

    1998-12-01

    In this study, proteolytic activity of Trichomonas tenax collected directly from patient's dentobacterial plaque was examined. Electrophoretic method involving polyacrylamide gels (Commassie Brilliant Blue R-250) and electrophoretic method involving gelatin-containing polyacrylamide gels, have been used to analyse Trichomonas tenax proteolytic activity. The most obvious and the fastest activities were obtained when gels were incubated in pH 4.6; followed by results of incubating in pH 5.6; while in pH 2.8 activity was less effective but still obvious. Proteolytic activities were the most effective in area of protein MW 36 kDa. Different activities of enzymes depending on pH of incubated media indicate the presence of different endopeptidases in cell lysates of protozoon Trichomonas tenax from dentobacterial plaque.

  8. A novel angiotensin-І converting enzyme (ACE) inhibitory peptide from gastrointestinal protease hydrolysate of silkworm pupa (Bombyx mori) protein: Biochemical characterization and molecular docking study.

    Science.gov (United States)

    Wu, Qiongying; Jia, Junqiang; Yan, Hui; Du, Jinjuan; Gui, Zhongzheng

    2015-06-01

    Silkworm pupa (Bombyx mori) protein was hydrolyzed using gastrointestinal endopeptidases (pepsin, trypsin and α-chymotrypsin). Then, the hydrolysate was purified sequentially by ultrafiltration, gel filtration chromatography and RP-HPLC. A novel ACE inhibitory peptide, Ala-Ser-Leu, with the IC50 value of 102.15μM, was identified by IT-MS/MS. This is the first report of Ala-Ser-Leu from natural protein. Lineweaver-Burk plots suggest that the peptide is a competitive inhibitor against ACE. The molecular docking studies revealed that the ACE inhibition of Ala-Ser-Leu is mainly attributed to forming very strong hydrogen bonds with the S1 pocket (Ala354) and the S2 pocket (Gln281 and His353). The results indicate that silkworm pupa (B. mori) protein or its gastrointestinal protease hydrolysate could be used as a functional ingredient in auxiliary therapeutic foods against hypertension.

  9. Matrix Metalloproteinase Inhibitors (MMPIs from Marine Natural Products: the Current Situation and Future Prospects

    Directory of Open Access Journals (Sweden)

    Se-Kwon Kim

    2009-03-01

    Full Text Available Matrix metalloproteinases (MMPs are a family of more than twenty five secreted and membrane-bound zinc-endopeptidases which can degrade extracellular matrix (ECM components. They also play important roles in a variety of biological and pathological processes. Matrix metalloproteinase inhibitors (MMPIs have been identified as potential therapeutic candidates for metastasis, arthritis, chronic inflammation and wrinkle formation. Up to present, more than 20,000 new compounds have been isolated from marine organisms, where considerable numbers of these naturally occurring derivatives are developed as potential candidates for pharmaceutical application. Eventhough the quantity of marine derived MMPIs is less when compare with the MMPIs derived from terrestrial materials, huge potential for bioactivity of these marine derived MMPIs has lead to large number of researches. Saccharoids, flavonoids and polyphones, fatty acids are the most important groups of MMPIs derived from marine natural products. In this review we focus on the progress of MMPIs from marine natural products.

  10. Crystal structures of Trypanosoma brucei oligopeptidase B broaden the paradigm of catalytic regulation in prolyl oligopeptidase family enzymes.

    Science.gov (United States)

    Canning, Peter; Rea, Dean; Morty, Rory E; Fülöp, Vilmos

    2013-01-01

    Oligopeptidase B cleaves after basic amino acids in peptides up to 30 residues. As a virulence factor in bacteria and trypanosomatid pathogens that is absent in higher eukaryotes, this is a promising drug target. Here we present ligand-free open state and inhibitor-bound closed state crystal structures of oligopeptidase B from Trypanosoma brucei, the causative agent of African sleeping sickness. These (and related) structures show the importance of structural dynamics, governed by a fine enthalpic and entropic balance, in substrate size selectivity and catalysis. Peptides over 30 residues cannot fit the enzyme cavity, preventing the complete domain closure required for a key propeller Asp/Glu to fix the catalytic His and Arg in the catalytically competent conformation. This size exclusion mechanism protects larger peptides and proteins from degradation. Similar bacterial prolyl endopeptidase and archael acylaminoacyl peptidase structures demonstrate this mechanism is conserved among oligopeptidase family enzymes across all three domains of life.

  11. Crystal structures of Trypanosoma brucei oligopeptidase B broaden the paradigm of catalytic regulation in prolyl oligopeptidase family enzymes.

    Directory of Open Access Journals (Sweden)

    Peter Canning

    Full Text Available Oligopeptidase B cleaves after basic amino acids in peptides up to 30 residues. As a virulence factor in bacteria and trypanosomatid pathogens that is absent in higher eukaryotes, this is a promising drug target. Here we present ligand-free open state and inhibitor-bound closed state crystal structures of oligopeptidase B from Trypanosoma brucei, the causative agent of African sleeping sickness. These (and related structures show the importance of structural dynamics, governed by a fine enthalpic and entropic balance, in substrate size selectivity and catalysis. Peptides over 30 residues cannot fit the enzyme cavity, preventing the complete domain closure required for a key propeller Asp/Glu to fix the catalytic His and Arg in the catalytically competent conformation. This size exclusion mechanism protects larger peptides and proteins from degradation. Similar bacterial prolyl endopeptidase and archael acylaminoacyl peptidase structures demonstrate this mechanism is conserved among oligopeptidase family enzymes across all three domains of life.

  12. Platelet apoptosis by cld-induced glycoportein Ibα clustering

    DEFF Research Database (Denmark)

    van der Wal, Dianne E; Du, V X; Lo, KS;

    2010-01-01

    take part in apoptosis regulation. Objectives and methods: We investigated whether GPIbα-clustering induces platelet apoptosis through 14-3-3 proteins during cold (4 h 0 °C)-rewarming (1 h 37 °C). Results: During cold-rewarming, 14-3-3 proteins associate with GPIbα and dissociate from Bad inducing Bad......-dephosphorylation and activation. This initiates pro-apoptosis changes in Bax/Bcl-xL and Bax-translocation to the mitochondria, inducing cytochrome c release. The result is activation of caspase-9, which triggers phosphatidylserine exposure and platelet phagocytosis by macrophages. Responses are prevented by N......-acetyl-d-glucosamine (GN), which blocks GPIbα-clustering, and by O-sialoglycoprotein endopeptidase, which removes extracellular GPIbα. Conclusions: Cold-rewarming triggers apoptosis through a GN-sensitive GPIbα-change indicative of receptor clustering. Attempts to improve platelet transfusion by cold-storage should focus...

  13. Crystallization and preliminary X-ray crystallographic analysis of the catalytic domain of membrane type 1 matrix metalloproteinase

    Science.gov (United States)

    Ogata, Hideaki; Decaneto, Elena; Grossman, Moran; Havenith, Martina; Sagi, Irit; Lubitz, Wolfgang; Knipp, Markus

    2014-01-01

    Membrane type 1 matrix metalloproteinase (MT1-MMP) belongs to the large family of zinc-dependent endopeptidases termed MMPs that are located in the extracellular matrix. MT1-MMP was crystallized at 277 K using the vapour-diffusion method with PEG as a precipitating agent. Data sets for MT1-MMP were collected to 2.24 Å resolution at 100 K. The crystals belonged to space group P43212, with unit-cell parameters a = 62.99, c = 122.60 Å. The crystal contained one molecule per asymmetric unit, with a Matthews coefficient (V M) of 2.90 Å3 Da−1; the solvent content is estimated to be 57.6%. PMID:24637763

  14. AtDeg2 – a chloroplast protein with dual protease/chaperone activity

    Directory of Open Access Journals (Sweden)

    Przemysław Jagodzik

    2014-07-01

    Full Text Available Chloroplast protease AtDeg2 (an ATP-independent serine endopeptidase is cytosolically synthesized as a precursor, which is imported into the chloroplast stroma and deprived of its transit peptide. Then the mature protein undergoes routing to its functional location at the stromal side of thylakoid membrane. In its linear structure AtDeg2 molecule contains the protease domain with catalytic triad (HDS and two PDZ domains (PDZ1 and PDZ2. In vivo AtDeg2 most probably exists as a supposedly inactive haxamer, which may change its oligomeric stage to form active 12-mer, or 24-mer. AtDeg2 has recently been demonstrated to exhibit dual protease/chaperone function. This review is focused on the current awareness with regard to AtDeg2 structure and functional significance.

  15. Signatures of positive selection at hemopexin (PEX) domain of matrix metalloproteinase-9 (MMP-9) gene

    Indian Academy of Sciences (India)

    Yang Liu; Yang Zhao; Chunlei Lu; Maobin Fu; Tonghai Dou; Xiaoming Tan

    2015-12-01

    Matrix metalloproteinases-9 (MMP-9) is an important cancer-associated, zinc-dependent endopeptidase. To investigate the natural selection hypothesis of MMP-9, the orthologous sequences from 12 vertebrates were compared and a molecular evolution analysis was performed. Results suggest that amino acid residues present in the middle region of the protein are more selectively constrained, whereas amino acid residues in the C-terminal region of the MM~P-9 protein including exon 13 showed lowest conservation level in non-primate species, suggesting that it is an exon with fast evolving rate compared to the others analyzed. InterProScan analysis shows that exon 13 was located in hemopexin (PEX) domain of MM~P-9. Positive selection was detected in PEX domain of MMP-9 protein between human and other species, which indicates that selective pressure may play a role in shaping the function of MM~P-9 in the course of evolution.

  16. Functionalized bismuth ferrite harmonic nanoparticles for cancer cells labeling and imaging

    Energy Technology Data Exchange (ETDEWEB)

    Passemard, Solène; Staedler, Davide; Sonego, Giona [Ecole Polytechnique Fédérale de Lausanne, Institute of Chemical Sciences and Engineering (Switzerland); Magouroux, Thibaud [Université de Genève, GAP-Biophotonics (Switzerland); Schneiter, Guillaume Stéphane [Ecole Polytechnique Fédérale de Lausanne, Institute of Chemical Sciences and Engineering (Switzerland); Juillerat-Jeanneret, Lucienne [University Institute of Pathology, CHUV-UNIL (Switzerland); Bonacina, Luigi [Université de Genève, GAP-Biophotonics (Switzerland); Gerber-Lemaire, Sandrine, E-mail: Sandrine.Gerber@epfl.ch [Ecole Polytechnique Fédérale de Lausanne, Institute of Chemical Sciences and Engineering (Switzerland)

    2015-10-15

    Bismuth ferrite (BFO) harmonic nanoparticles (NPs) display high nonlinear optical efficiency and excellent biocompatibility profile which make them attractive for the development of diagnostic applications as contrast agents. In this study, we present a general method for the functionalization of this material with chemical ligands targeting cancer molecular biomarkers. In particular, a conjugation protocol based on click reaction between alkynyl-containing targeting ligands and poly(ethylene glycol)-coated BFO NPs (67.7 nm) displaying surface reactive azido groups was developed. Copper-free click reaction allowed fast and efficient conjugation of a covalent inhibitor of prolyl-specific endopeptidases to coated BFO NPs. The ability of these functionalized nanomaterials (134.2 nm) to act as imaging probes for cancer cells was demonstrated by the selective labeling of human lung cancer cells.

  17. The membrane localization domains of two distinct bacterial toxins form a 4-helix-bundle in solution.

    Science.gov (United States)

    Hisao, Grant S; Brothers, Michael C; Ho, Mengfei; Wilson, Brenda A; Rienstra, Chad M

    2017-03-01

    Membrane localization domain (MLD) was first proposed for a 4-helix-bundle motif in the crystal structure of the C1 domain of Pasteurella multocida toxin (PMT). This structure motif is also found in the crystal structures of several clostridial glycosylating toxins (TcdA, TcdB, TcsL, and TcnA). The Ras/Rap1-specific endopeptidase (RRSP) module of the multifunctional autoprocessing repeats-in-toxins (MARTX) toxin produced by Vibrio vulnificus has sequence homology to the C1-C2 domains of PMT, including a putative MLD. We have determined the solution structure for the MLDs in PMT and in RRSP using solution state NMR. We conclude that the MLDs in these two toxins assume a 4-helix-bundle structure in solution. © 2016 The Protein Society.

  18. Hypophosphatemic Rickets in Siblings: A Rare Case Report

    Directory of Open Access Journals (Sweden)

    Gummadapu Sarat

    2016-01-01

    Full Text Available Hypophosphatemic rickets (HR is a type of hereditary rickets characterized by persistent hypophosphatemia and hyperphosphaturia. The most predominant type is inherited in an X-linked fashion and caused by mutation in the gene encoding the phosphate-regulating endopeptidase homolog, X-linked (PHEX, identified in 1995. The X-linked hypophosphatemic (XLH rickets is a rare hereditary metabolic disorder with a prevalence of 1 in 20,000 and causes deficient calcification of mineralized structures such as bones and teeth resulting in dental problems in terms of delayed eruption, spontaneous periapical infections, and exfoliation. We report one such unique case of hypophosphatemic vitamin D-resistant rickets in siblings exhibiting classical features of rickets with emphasis on its treatment and dental considerations.

  19. Hypophosphatemic Rickets in Siblings: A Rare Case Report

    Science.gov (United States)

    Sarat, Gummadapu; Priyanka, Nuthalapati; Prabhat, Meka Purna Venkata; Raja Lakshmi, Chintamaneni; Ayesha Thabusum, Dharmavaram

    2016-01-01

    Hypophosphatemic rickets (HR) is a type of hereditary rickets characterized by persistent hypophosphatemia and hyperphosphaturia. The most predominant type is inherited in an X-linked fashion and caused by mutation in the gene encoding the phosphate-regulating endopeptidase homolog, X-linked (PHEX), identified in 1995. The X-linked hypophosphatemic (XLH) rickets is a rare hereditary metabolic disorder with a prevalence of 1 in 20,000 and causes deficient calcification of mineralized structures such as bones and teeth resulting in dental problems in terms of delayed eruption, spontaneous periapical infections, and exfoliation. We report one such unique case of hypophosphatemic vitamin D-resistant rickets in siblings exhibiting classical features of rickets with emphasis on its treatment and dental considerations. PMID:27340574

  20. Free radicals in tobacco smoke – analytical approach and biomedical significanc

    Directory of Open Access Journals (Sweden)

    Leon Kośmider

    2013-09-01

    Full Text Available Free radicals, i.e. atoms or groups of atoms containing one or more unpaired electrons, are significant constituents of tobacco smoke that contribute to its toxic properties. Radicals are generated during complex pyrolysis and combustion reactions in burning a cigarette cone. It has been shown that some free radicals found in tobacco smoke have relatively long half-time life (over 5 mins. We have reviewed modern analytical methods used for identification and quantitative analysis of free radicals in tobacco smoke, particularly the electron paramagnetic resonance combined with a spin-trapping approach. We also discussed the role of free radicals in etiology of respiratory and cardiovascular conditions among smokers. Finally, we reviewed biochemical mechanisms of various pathological conditions, including disturbances in lipid peroxidation, activity modification of lecithin-cholesterol acyltransferase and level high density lipoprotein, hyperactivity to substance P, and inactivation of neutral endopeptidase, that are thought to be contributed by free radicals from tobacco smoke.

  1. FAP finds FGF21 easy to digest

    DEFF Research Database (Denmark)

    Gillum, Matthew P; Potthoff, Matthew J

    2016-01-01

    Fibroblast growth factor 21 (FGF21) is an endocrine hormone that regulates carbohydrate and lipid metabolism. In humans, circulating FGF21 is inactivated by proteolytic cleavage of its C-terminus, thereby preventing signalling through a receptor complex. The mechanism for this cleavage event...... and the factors contributing to the post-translational regulation of FGF21 activity has previously been unknown. In a recent issue of the Biochemical Journal, Zhen et al. have identified fibroblast activation protein (FAP) as the endopeptidase responsible for this site-specific cleavage of human FGF21 (hFGF21......), and propose that inhibition of FAP may be a therapeutic strategy to increase endogenous levels of active FGF21....

  2. The influence of pH, polyethylene glycol and polyacrylic acid on the stability of stem bromelain

    Directory of Open Access Journals (Sweden)

    Letícia Celia de Lencastre Novaes

    2014-04-01

    Full Text Available Enzyme stability is critical in biotechnology, pharmaceutical and cosmetic industries. Investigations on this subject have drawn attention because of its practical application. Bromelain is a thiol-endopeptidase, obtained from pineapple (Ananas comosus, known for its clinical and therapeutic applications, particularly to selective burn debridement and improvement of antibiotic action and anti-inflammatory activities. To date, the use of bromelain in pharmacological or industrial applications is limited, due to commercial availability, costs, and sensitivity to pH and temperature. Therefore, a better understanding of enzyme stability would be of great interest. The aim of this study was to evaluate bromelain activity and stability in several pH (2.0 to 8.0 and in polyethylene glycol and polyacrylic acid solutions. We observed that bromelain was able to maintain its stability at pH 5.0 for the temperatures studied. PEG solutions increased bromelain stability, but PAA solutions had the opposite effect.

  3. Irradiation effects on hydrases for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu E-mail: mfuruta@riast.osakafu-u.ac.jp; Ohashi, Isao; Oka, Masahito; Hayashi, Toshio

    2000-03-01

    To apply an irradiation technique to sterilize 'Hybrid' biomedical materials including enzymes, we selected papain, a well-characterized plant endopeptidase as a model to examine durability of enzyme activity under the practical irradiation condition in which limited data were available for irradiation inactivation of enzymes. Dry powder and frozen aqueous solution of papain showed significant durability against {sup 60}Co-gamma irradiation suggesting that, the commercial irradiation sterilizing method is applicable without modification. Although irradiation of unfrozen aqueous papain solution showed an unusual change of the enzymatic activity with the increasing doses, and was totally inactivated at 15 kGy, we managed to keep the residual activity more than 50% of initial activity after 30-kGy irradiation, taking such optimum conditions as increasing enzyme concentration from 10 to 100 mg/ml and purging with N{sub 2} gas to suppress the formation of free radicals. (author)

  4. Secreted fungal aspartic proteases: A review.

    Science.gov (United States)

    Mandujano-González, Virginia; Villa-Tanaca, Lourdes; Anducho-Reyes, Miguel Angel; Mercado-Flores, Yuridia

    2016-01-01

    The aspartic proteases, also called aspartyl and aspartate proteases or acid proteases (E.C.3.4.23), belong to the endopeptidase family and are characterized by the conserved sequence Asp-Gly-Thr at the active site. These enzymes are found in a wide variety of microorganisms in which they perform important functions related to nutrition and pathogenesis. In addition, their high activity and stability at acid pH make them attractive for industrial application in the food industry; specifically, they are used as milk-coagulating agents in cheese production or serve to improve the taste of some foods. This review presents an analysis of the characteristics and properties of secreted microbial aspartic proteases and their potential for commercial application. Copyright © 2016 Asociación Española de Micología. Published by Elsevier Espana. All rights reserved.

  5. Searching for halo-alkalophilic proteases maintaining stability and activity in hydrophilic aprotic solvents as biocatalysts in carbohydrate chemistry

    DEFF Research Database (Denmark)

    Pedersen, Lars Haastrup; Mørkholt, Camilla Kær; Nielsen, Carsten Bue

    2012-01-01

    and other carbohydrates (1, 2). Therefore, we are searching for new bacterial halo-alkaline proteases from extreme environments in Denmark. So far we have identified a number of interesting isolates showing proteolytic activity at pH 7 and 10. Whole genome Illumina Hiseq 2000 amplicon sequencing, de novo...... assembly of the genome and automatic annotation of genes in the genome was carried out by RAST to find the genes responsible for protease production. The amino-acid sequence of the expressed proteolytic proteins was analyzed using tandem MS. The isolates identified so far belong to Bacillus sp. One...... of the interesting genomes with a total length of 4.1 Mb was assembled in 42 contigs with a total of 3070 known genes of which 39 are encoding for proteases (one serine endopeptidase). Another genome was assembled in 219 contigs with 4004 coding sequences and 2821 known genes of which 36 are encoding for proteases...

  6. Properties and therapeutic application of bromelain: a review.

    Science.gov (United States)

    Pavan, Rajendra; Jain, Sapna; Shraddha; Kumar, Ajay

    2012-01-01

    Bromelain belongs to a group of protein digesting enzymes obtained commercially from the fruit or stem of pineapple. Fruit bromelain and stem bromelainare prepared differently and they contain different enzymatic composition. "Bromelain" refers usually to the "stem bromelain." Bromelain is a mixture of different thiol endopeptidases and other components like phosphatase, glucosidase, peroxidase, cellulase, escharase, and several protease inhibitors. In vitro and in vivo studies demonstrate that bromelain exhibits various fibrinolytic, antiedematous, antithrombotic, and anti-inflammatory activities. Bromelain is considerably absorbable in the body without losing its proteolytic activity and without producing any major side effects. Bromelain accounts for many therapeutic benefits like the treatment of angina pectoris, bronchitis, sinusitis, surgical trauma, and thrombophlebitis, debridement of wounds, and enhanced absorption of drugs, particularly antibiotics. It also relieves osteoarthritis, diarrhea, and various cardiovascular disorders. Bromelain also possesses some anticancerous activities and promotes apoptotic cell death. This paper reviews the important properties and therapeutic applications of bromelain, along with the possible mode of action.

  7. Brachypodium distachyon as a model for defining the allergen potential of non-prolamin proteins.

    Science.gov (United States)

    Juhász, A; Gell, Gy; Sebestyén, E; Haraszi, R; Tamás, L; Balázs, E

    2012-08-01

    Epitope databases and the protein sequences of published plant genomes are suitable to identify some of the proteins causing food allergies and sensitivities. Brachypodium distachyon, a diploid wild grass with a sequenced genome and low prolamin content, is the closest relative of the allergen cereals, such as wheat or barley. Using the Brachypodium genome sequence, a workflow has been developed to identify potentially harmful proteins which may cause either celiac disease or wheat allergy-related symptoms. Seed tissue-specific expression of the potential allergens has been determined, and intact epitopes following an in silico digestion with several endopeptidases have been identified. Molecular function of allergen proteins has been evaluated using Gene Ontology terms. Biologically overrepresented proteins and potentially allergen protein families have been identified.

  8. Sulphonamide 1,4-dithia-7-azaspiro[4,4]nonane derivatives as gelatinase A inhibitors.

    Science.gov (United States)

    Shi, Leilei; Wang, Qiang; Wang, Haina; Zhou, Hua; Li, Yonggang; Li, Xun

    2013-12-15

    Gelatinase A, a zinc-containing endopeptidase, has been shown to be an essential therapeutic target for tumor intervention owing to its participation in almost all types of solid tumors. Based on our previous work with respect to quinoxalinone peptidomimetics, a novel series of sulphonamide-containing 1,4-dithia-7-azaspiro[4,4]nonane (DAN) derivatives have been synthesized and evaluated as potential gelatinase A inhibitors hereby. The results revealed that the majority of tested compounds displayed satisfactory inhibition activity against gelatinase A. Among the tested compounds, 2b, 3a, 4a-d, 6a, 6d, 7a-d exhibited more potent gelatinase A inhibition than the positive control LY52. Furthermore, two test compounds 2b and 6a demonstrated moderate anti-proliferative in vitro and anti-metastatic activities in vivo, which might be utilized as potential leads in future chemical optimization.

  9. Functional expression of human leukocyte elastase (HLE)/medullasin in eukaryotic cells.

    Science.gov (United States)

    Okano, K; Aoki, Y; Shimizu, H; Naruto, M

    1990-03-30

    We have cloned a full length cDNA for human leukocyte elastase (HLE, EC 3.4.21.37)/medullasin from the cDNA library of human leukemic cell line, ML3. Recombinant plasmid for the expression of HLE cDNA in eukaryotic cells was constructed in which HLE cDNA was fused in a frame to a leader sequence of human interleukin-2 (IL-2). COS-1 cells, transfected with the plasmid, secreted fusion protein consists of N-terminal 8 amino acid (aa) residues of human IL-2 and 238 aa residues of HLE. As the fusion protein was designed to be connected through lysine residue, elastase activity was generated after digestion of the fusion protein with lysyl-endopeptidase.

  10. H-Lys-Arg-Asn-Lys-Asn-Asn-OH is the minimal active structure of oxyntomodulin.

    Science.gov (United States)

    Carles-Bonnet, C; Martinez, J; Jarrousse, C; Aumelas, A; Niel, H; Bataille, D

    1996-01-01

    Oxyntomodulin inhibits gastric acid secretion via its C-terminal octapeptide. Its minimal active structure was delineated by testing, on histamine-stimulated gastric acid secretion in the conscious rat, the inhibitory effect of octapeptide analogues, shortened either or both on their N- or C- terminus. The octapeptide may be simplified by deleting the two C-terminal amino acids while keeping its efficacy and the slope of the dose-response curve. Suppressing the first N-terminal amino acid dramatically decreased the activity. The nonprotected peptides are metabolized by aminopeptidases and endopeptidases. The increased potency of the N-acetylated forms is related, at least in part, with their protection against aminopeptidases.

  11. Multienzyme Modification of Hemp Protein for Functional Peptides Synthesis

    Directory of Open Access Journals (Sweden)

    Ranjana Das

    2015-01-01

    Full Text Available Functional foods and nutraceuticals are of special importance, particularly for their impact on human health and prevention of certain chronic diseases. Consequently, the production and properties of bioactive peptides have received an increasing scientific interest over past few years. Present work intends to compare the competence of metalloendopeptidases (“Protease N” and “Protease A” with papain for getting functional peptides from hemp seed meal, which is an obligatory waste of hemp fiber production industry. As a measure of the functional potential hemp protein hydrolysates were analyzed for their antiradical properties in DPPH system. “Protease N” modified protein hydrolysate exhibited comparatively superior radical scavenging activity in DPPH system. Overall findings represent the importance of “Protease N,” as endopeptidase in getting peptides of good antiradical properties from various protein sources.

  12. Novel targets for immunotherapy in glomerulonephritis

    Directory of Open Access Journals (Sweden)

    Mary H Foster

    2008-09-01

    Full Text Available Mary H FosterDepartment of Medicine and Research Service, Duke University Medical Center and Durham Veterans Affairs Medical Center, Durham, North Carolina, USAAbstract: Glomerulonephritis is a common cause of chronic kidney disease and end stage renal failure. Current therapy relies on variably effective, nonspecific and toxic immunosuppression. Recent insights into underlying biology and disease pathogenesis in human glomerulonephritis combined with advances in the fields of inflammation and autoimmunity promise a cadre of novel targeted interventions. This review highlights the therapeutic potential of two antigens, alpha3 (IVNC1 collagen and podocyte neutral endopeptidase, and two cell signaling and effector molecules, IgG Fc receptors and complement, judged to be particularly amenable to therapeutic manipulation in man. It is anticipated that continued dissection of pathogenesis in the diverse disorders that comprise the glomerulonephritides will provide the basis for individualized disease-specific therapy.Keywords: glomerulonephritis, immunotherapy, Goodpasture syndrome, membranous nephropathy

  13. Substrate-induced activation of a trapped IMC-mediated protein folding intermediate.

    Science.gov (United States)

    Inouye, M; Fu, X; Shinde, U

    2001-04-01

    While several unfolded proteins acquire native structures through distinct folding intermediates, the physiological relevance and importance of such states in the folding kinetics remain controversial. The intramolecular chaperone (IMC) of subtilisin was used to trap a partially folded, stable crosslinked intermediate conformer (CLIC) through a disulfide bond between mutated IMC and subtilisin. The trapped CLIC contains non-native interactions. Here we show that CLIC can be induced into a catalytically active form by incubating it with small peptide substrates. The structure and catalytic properties of the activated crosslinked intermediate conformer (A-CLIC) differ from those of the fully folded enzyme in that A-CLIC lacks any endopeptidase activity toward a large protein substrate. Our results show that a disulfide-linked partially folded protein can be induced to acquire catalytic activity with a substrate specificity that is different from completely folded subtilisin. These results also suggest that protein folding intermediates may also participate in catalytic reactions.

  14. Matrix metalloproteinases and their expression in mammary gland

    Institute of Scientific and Technical Information of China (English)

    URIAJOSEA; ZENAWERB

    1998-01-01

    The matrix metalloproteinases (MMPs) are a family of zine-dependent endopeptidases that play a key role in both normal and pathological processes involving tissue remodeling events.The expression of these proteolytic enzymes is highly regulated by a balance between extracellular matrix (ECM) deposition and its degradation,and is controlled by growth factors,cytokines,hormones,as well as interactions with the ECM macromolecules.Furthermore,the activity of the MMPs is regulated by their natural endogenous inhibitors,which are members of the tissue inhibitor of metalloproteinases (TIMP) family.In the normal mammary gland,MMPs are expressed during ductal development,lobulo-alveolar development in pregnancy and involution after lactation.Under pathological conditions,such as tumorigenesis,the dysregulated expression of MMPs play a role in tumor initiation,progression and malignant conversion as well as facilitating invasion and metastasis of malignant cells through degradation of the ECM and basement membranes.

  15. MMP-1 polymorphism and its relationship to pathological processes

    Indian Academy of Sciences (India)

    P A Arakaki; M R Marques; M C L G Santos

    2009-06-01

    Matrix metalloproteinases (MMPs) are a family of zinc (Zn)-dependent endopeptidases that are collectively capable of cleaving virtually all extracellular matrix (ECM) substrates and play an important role in diverse physiological and pathological processes. The activity of MMPs is regulated at multiple levels. The transcriptional regulation of MMP appears to represent the key step in MMP regulation. There are diverse types of MMPs that differ structural and functionally. MMP-1 is the most ubiquitously expressed interstitial collagenase and has a prominent role in initial cleavage of the ECM. The level of MMP-1 expression can be influenced by different single-nucleotide polymorphisms (SNPs) in the promoter region. A functional polymorphism at position –1607 has been shown to alter the transcriptional activity of MMP-1 and was associated with diverse pathological processes. The aim of our review was to discuss some topics related to MMP in physiological and pathological processes, with a focus on MMP-1 polymorphism.

  16. Expression and function of the ACE2/angiotensin(1-7)/Mas axis in osteosarcoma cell lines U-2 OS and MNNG-HOS.

    Science.gov (United States)

    Ender, Stephan Albrecht; Dallmer, Andrea; Lässig, Florian; Lendeckel, Uwe; Wolke, Carmen

    2014-08-01

    The renin-angiotensin-system (RAS), via its classical angiotensin-converting enzyme (ACE)/angiotensin II/angiotensin II type 1 receptor (AT1R)-axis, is associated with proliferation and metastasis of numerous types of solid tumor. AT1R blockers reduce tumor volume and decrease liver and lung metastasis in murine models of osteosarcoma. Expression and function of the alternative ACE2/Ang(1-7)/Mas axis in osteosarcoma is yet to be studied. In the present study, the basic and interleukin (IL)-1β-stimulated expression of components of this alternative RAS axis were analyzed and the impact of Mas on proliferation and/or migration of U-2 OS and MNNG-HOS osteosarcoma cells was studied. Quantitative polymerase chain reaction revealed that the two cell lines expressed the Ang(1‑7)-generating peptidases ACE2, neutral endopeptidase 24.11 and prolyl-endopeptidase together with the putative receptor for Ang(1-7), Mas. IL-1β provoked an induction of Mas mRNA and protein expression which was associated with a reduction of proliferation and migration. By contrast, small interfering RNA-mediated knockdown of Mas expression led to increased cell proliferation. In conclusion, osteosarcoma cells express a functional active alternative ACE2/Ang(1-7)/Mas axis. The induction and reinforcement of this axis may be beneficial for the treatment of osteosarcoma by reducing growth and preventing cancer metastasis. These effects may be achieved directly by the administration of Mas agonists or, indirectly, via blocking the classical AngII RAS axis via ACE inhibitors or AT1R antagonists.

  17. Metabolism of oxytocin in rat uterus and placenta in late gestation.

    Science.gov (United States)

    Mitchell, B F; Fang, X; Wong, S

    1997-10-01

    Concentrations of oxytocin (OT) peptide increase in rat uterine tissues at the time of parturition. We have measured the rate of OT metabolism in these tissues in late gestation to determine whether a decrease in OT catabolism is responsible for the increase in OT concentrations. Uterine and placental tissues were obtained from groups of rats at Days 16, 19, 21, 21.5, 22, and after delivery of the first pup. Delivery usually occurs in the early afternoon of Day 22. Some animals were treated with the estrogen receptor blocker tamoxifen, which will delay parturition by approximately 24 h. Cytosolic and microsomal preparations obtained using ultracentrifugation were incubated with radiolabeled OT. Metabolites were separated using HPLC, and enzyme kinetic parameters were calculated. OT was actively metabolized in both uterine and placental tissues. Total oxytocinase activity was similar in the two tissues. In uterine tissues, activity was greater in the cytosolic fractions. In placenta, activity was evenly distributed between the cytosolic and microsomal fractions. The cytosolic fractions of each tissue contained predominantly post-proline endopeptidase activity, whereas the microsomes contained predominantly aminopeptidase activity. There was a slight trend to decreasing oxytocinase activity with advancing gestation in both subcellular fractions, but this was statistically significant only in the microsomal fraction. The maximal decline in activity was only 25-50%. Tamoxifen treatment had no effect on oxytocinase activity. We conclude that rat uterine and placental tissues contain post-proline endopeptidase and aminopeptidase activities that metabolize OT. It is doubtful that changes in these activities are major factors in regulating the increase in OT concentrations measured in rat intrauterine tissues at the time of parturition.

  18. N-α-PGP and PGP, potential biomarkers and therapeutic targets for COPD

    Directory of Open Access Journals (Sweden)

    Gaggar Amit

    2009-05-01

    Full Text Available Abstract Background Chronic obstructive pulmonary disease (COPD is a common respiratory disorder for which new diagnostic and therapeutic approaches are required. Hallmarks of COPD are matrix destruction and neutrophilic airway inflammation in the lung. We have previously described two tri-peptides, N-α-PGP and PGP, which are collagen fragments and neutrophil chemoattractants. In this study, we investigate if N-α-PGP and PGP are biomarkers and potential therapeutic targets for COPD. Methods Induced sputum samples from COPD patients, healthy controls and asthmatics were examined for levels of N-α-PGP and PGP using mass spectrometry and for the ability to generate PGP de novo from collagen. Proteases important in PGP generation in the lung were identified by the use of specific inhibitors in the PGP generation assay and by instillation of proteases into mouse lungs. Serum levels of PGP were compared between COPD patients and controls. Results N-α-PGP was detected in most COPD sputum samples but in no asthmatics or controls. PGP was detected in a few controls and in all COPD sputum samples, where it correlated with levels of myeloperoxidase. COPD sputum samples had the ability to generate N-α-PGP and PGP de novo from collagen. PGP generation by COPD sputum was blocked by inhibitors of matrix metalloproteases (MMP's 1 and 9 and prolyl endopeptidase. MMP's 1 and 9 and prolyl endopeptidase acted synergistically to generate PGP in vivo when instilled into mouse lungs. Serum levels of PGP were also significantly higher in COPD patients than in controls Conclusion N-α-PGP and PGP may represent novel diagnostic tests and biomarkers for COPD. Inhibition of this pathway may provide novel therapies for COPD directed at the chronic, neutrophilic, airway inflammation which underlies disease progression.

  19. Monoclonal Antibodies Targeting the Alpha-Exosite of Botulinum Neurotoxin Serotype/A Inhibit Catalytic Activity.

    Directory of Open Access Journals (Sweden)

    Yongfeng Fan

    Full Text Available The paralytic disease botulism is caused by botulinum neurotoxins (BoNT, multi-domain proteins containing a zinc endopeptidase that cleaves the cognate SNARE protein, thereby blocking acetylcholine neurotransmitter release. Antitoxins currently used to treat botulism neutralize circulating BoNT but cannot enter, bind to or neutralize BoNT that has already entered the neuron. The light chain endopeptidase domain (LC of BoNT serotype A (BoNT/A was targeted for generation of monoclonal antibodies (mAbs that could reverse paralysis resulting from intoxication by BoNT/A. Single-chain variable fragment (scFv libraries from immunized humans and mice were displayed on the surface of yeast, and 19 BoNT/A LC-specific mAbs were isolated by using fluorescence-activated cell sorting (FACS. Affinities of the mAbs for BoNT/A LC ranged from a KD value of 9.0×10-11 M to 3.53×10-8 M (mean KD 5.38×10-9 M and median KD 1.53×10-9 M, as determined by flow cytometry analysis. Eleven mAbs inhibited BoNT/A LC catalytic activity with IC50 values ranging from 8.3 ~73×10-9 M. The fine epitopes of selected mAbs were also mapped by alanine-scanning mutagenesis, revealing that the inhibitory mAbs bound the α-exosite region remote from the BoNT/A LC catalytic center. The results provide mAbs that could prove useful for intracellular reversal of paralysis post-intoxication and further define epitopes that could be targeted by small molecule inhibitors.

  20. Sequence characterization and immunogenicity of cystatins from the cattle tick Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Parizi, Luís F; Githaka, Naftaly W; Acevedo, Carolina; Benavides, Uruguaysito; Seixas, Adriana; Logullo, Carlos; Konnai, Satoru; Ohashi, Kazuhiko; Masuda, Aoi; da Silva Vaz, Itabajara

    2013-12-01

    Various classes of endopeptidases and their inhibitors facilitate blood feeding and digestion in ticks. Cystatins, a family of tight-binding and reversible inhibitors of cysteine endopeptidases, have recently been found in several tick tissues. Moreover, vaccine trials using tick cystatins have been found to induce protective immune responses against tick infestation. However, the mode of action of tick cystatins is still poorly understood, limiting the elucidation of their physiological role. Against this background, we have investigated sequence characteristics and immunogenic properties of 5 putative cystatins from Rhipicephalus (Boophilus) microplus from Brazil and Uruguay. The similarity of the deduced amino acid sequences among cystatins from the Brazilian tick strain was 27-42%, all of which had a secretory signal peptide. The cystatin motif (QxVxG), a glycine in the N-terminal region, and the PW motif in the second hairpin loop in the C-terminal region are highly conserved in all 5 cystatins identified in this study. Four cysteine residues in the C terminus characteristic of type 2 cystatins are also present. qRT-PCR revealed differential expression patterns among the 5 cystatins identified, as well as variation in mRNA transcripts present in egg, larva, gut, salivary glands, ovary, and fat body tissues. One R. microplus cystatin showed 97-100% amino acid similarity between Brazilian and Uruguayan isolates. Furthermore, by in silico analysis, antigenic amino acid regions from R. microplus cystatins showed high degrees of homology (54-92%) among Rhipicephalus spp. cystatins. Three Brazilian R. microplus cystatins were expressed in Escherichia coli, and immunogenicity of the recombinant proteins were determined by vaccinating mice. Western blotting using mice sera indicated cross-reactivity between the cystatins, suggesting shared epitopes. The present characterization of Rhipicephalus spp. cystatins represents an empirical approach in an effort to evaluate

  1. Nanoelectrode and nanoparticle based biosensors for environmental and health monitoring

    Science.gov (United States)

    Syed, Lateef Uddin

    Reduction in electrode size down to nanometers dramatically enhances the detection sensitivity and temporal resolution. Here we explore nanoelectrode arrays (NEAs) and nanoparticles in building high performance biosensors. Vertically aligned carbon nanofibers (VACNFs) of diameter ˜100 nm were grown on a Si substrate using plasma enhanced chemical vapor deposition. SiO2 embedded CNF NEAs were then fabricated using techniques like chemical vapor deposition, mechanical polishing, and reactive ion etching, with CNF tips exposed at the final step. The effect of the interior structure of CNFs on electron transfer rate (ETR) was investigated by covalently attaching ferrocene molecules to the exposed end of CNFs. Anomalous differences in the ETR were observed between DC voltammetry (DCV) and AC voltammetry (ACV). The findings from this study are currently being extended to develop an electrochemical biosensor for the detection of cancerous protease (legumain). Preliminary results with standard macro glassy carbon electrodes show a significant decrease in ACV signal, which is encouraging. In another study, NEA was employed to capture and detect pathogenic bacteria using AC dielectrophoresis (DEP) and electrochemical impedance spectroscopy (EIS). A nano-DEP device was fabricated using photolithography processes to define a micro patterned exposed active region on NEA and a microfluidic channel on macro-indium tin oxide electrode. Enhanced electric field gradient at the exposed CNF tips was achieved due to the nanometer size of the electrodes, because of which each individual exposed tip can act as a potential DEP trap to capture the pathogen. Significant decrease in the absolute impedance at the NEA was also observed by EIS experiments. In a final study, we modified gold nanoparticles (GNPs) with luminol to develop chemiluminescence (CL) based blood biosensor. Modified GNPs were characterized by UV-Vis, IR spectroscopy and TEM. We have applied this CL method for the

  2. Bioinformatics and expression analyses of the Ixodes scapularis tick cystatin family.

    Science.gov (United States)

    Ibelli, Adriana Mércia Guaratini; Hermance, Meghan M; Kim, Tae Kwon; Gonzalez, Cassandra Lee; Mulenga, Albert

    2013-05-01

    The cystatins are inhibitors of papain- and legumain-like cysteine proteinases, classified in MEROPS subfamilies I25A-I25C. This study shows that 84 % (42/50) of tick cystatins are putatively extracellular in subfamily I25B and the rest are putatively intracellular in subfamily I25A. On the neighbor joining phylogeny guide tree, subfamily I25A members cluster together, while subfamily I25B cystatins segregate among prostriata or metastriata ticks. Two Ixodes scapularis cystatins, AAY66864 and ISCW011771 that show 50-71 % amino acid identity to metastriata tick cystatins may be linked to pathways that are common to all ticks, while ISCW000447 100 % conserved in I. ricinus is important among prostriata ticks. Likewise metastriata tick cystatins, Dermacentor variabilis-ACF35512, Rhipicephalus microplus-ACX53850, A. americanum-AEO36092, R. sanguineus-ACX53922, D. variabilis-ACF35514, R. sanguineus-ACX54033 and A. maculatum-AEO35155 that show 73-86 % amino acid identity may be essential to metastriata tick physiology. RT-PCR expression analyses revealed that I. scapularis cystatins were constitutively expressed in the salivary glands, midguts and other tissues of unfed ticks and ticks that were fed for 24-120 h, except for ISCW017861 that are restricted to the 24 h feeding time point. On the basis of mRNA expression patterns, I. scapularis cystatins, ISCW017861, ISCW011771, ISCW002215 and ISCW0024528 that are highly expressed at 24 h are likely involved in regulating early stage tick feeding events such as tick attachment onto host skin and creation of the feeding lesion. Similarly, ISCW018602, ISCW018603 and ISCW000447 that show 2-3 fold transcript increase by 120 h of feeding are likely associated with blood meal up take, while those that maintain steady state expression levels (ISCW018600, ISCW018601 and ISCW018604) during feeding may not be associated with tick feeding regulation. We discuss our findings in the context of advancing our knowledge of tick

  3. Comparative transcriptomics of elasmobranchs and teleosts highlight important processes in adaptive immunity and regional endothermy.

    Science.gov (United States)

    Marra, Nicholas J; Richards, Vincent P; Early, Angela; Bogdanowicz, Steve M; Pavinski Bitar, Paulina D; Stanhope, Michael J; Shivji, Mahmood S

    2017-01-30

    Comparative genomic and/or transcriptomic analyses involving elasmobranchs remain limited, with genome level comparisons of the elasmobranch immune system to that of higher vertebrates, non-existent. This paper reports a comparative RNA-seq analysis of heart tissue from seven species, including four elasmobranchs and three teleosts, focusing on immunity, but concomitantly seeking to identify genetic similarities shared by the two lamnid sharks and the single billfish in our study, which could be linked to convergent evolution of regional endothermy. Across seven species, we identified an average of 10,877 Swiss-Prot annotated genes from an average of 32,474 open reading frames within each species' heart transcriptome. About half of these genes were shared between all species while the remainder included functional differences between our groups of interest (elasmobranch vs. teleost and endotherms vs. ectotherms) as revealed by Gene Ontology (GO) and selection analyses. A repeatedly represented functional category, in both the uniquely expressed elasmobranch genes (total of 259) and the elasmobranch GO enrichment results, involved antibody-mediated immunity, either in the recruitment of immune cells (Fc receptors) or in antigen presentation, including such terms as "antigen processing and presentation of exogenous peptide antigen via MHC class II", and such genes as MHC class II, HLA-DPB1. Molecular adaptation analyses identified three genes in elasmobranchs with a history of positive selection, including legumain (LGMN), a gene with roles in both innate and adaptive immunity including producing antigens for presentation by MHC class II. Comparisons between the endothermic and ectothermic species revealed an enrichment of GO terms associated with cardiac muscle contraction in endotherms, with 19 genes expressed solely in endotherms, several of which have significant roles in lipid and fat metabolism. This collective comparative evidence provides the first multi

  4. Ribosomal oxygenases are structurally conserved from prokaryotes to humans.

    Science.gov (United States)

    Chowdhury, Rasheduzzaman; Sekirnik, Rok; Brissett, Nigel C; Krojer, Tobias; Ho, Chia-Hua; Ng, Stanley S; Clifton, Ian J; Ge, Wei; Kershaw, Nadia J; Fox, Gavin C; Muniz, Joao R C; Vollmar, Melanie; Phillips, Claire; Pilka, Ewa S; Kavanagh, Kathryn L; von Delft, Frank; Oppermann, Udo; McDonough, Michael A; Doherty, Aiden J; Schofield, Christopher J

    2014-06-19

    2-Oxoglutarate (2OG)-dependent oxygenases have important roles in the regulation of gene expression via demethylation of N-methylated chromatin components and in the hydroxylation of transcription factors and splicing factor proteins. Recently, 2OG-dependent oxygenases that catalyse hydroxylation of transfer RNA and ribosomal proteins have been shown to be important in translation relating to cellular growth, TH17-cell differentiation and translational accuracy. The finding that ribosomal oxygenases (ROXs) occur in organisms ranging from prokaryotes to humans raises questions as to their structural and evolutionary relationships. In Escherichia coli, YcfD catalyses arginine hydroxylation in the ribosomal protein L16; in humans, MYC-induced nuclear antigen (MINA53; also known as MINA) and nucleolar protein 66 (NO66) catalyse histidine hydroxylation in the ribosomal proteins RPL27A and RPL8, respectively. The functional assignments of ROXs open therapeutic possibilities via either ROX inhibition or targeting of differentially modified ribosomes. Despite differences in the residue and protein selectivities of prokaryotic and eukaryotic ROXs, comparison of the crystal structures of E. coli YcfD and Rhodothermus marinus YcfD with those of human MINA53 and NO66 reveals highly conserved folds and novel dimerization modes defining a new structural subfamily of 2OG-dependent oxygenases. ROX structures with and without their substrates support their functional assignments as hydroxylases but not demethylases, and reveal how the subfamily has evolved to catalyse the hydroxylation of different residue side chains of ribosomal proteins. Comparison of ROX crystal structures with those of other JmjC-domain-containing hydroxylases, including the hypoxia-inducible factor asparaginyl hydroxylase FIH and histone N(ε)-methyl lysine demethylases, identifies branch points in 2OG-dependent oxygenase evolution and distinguishes between JmjC-containing hydroxylases and demethylases

  5. Hypoxia-dependent sequestration of an oxygen sensor by a widespread structural motif can shape the hypoxic response - a predictive kinetic model

    Directory of Open Access Journals (Sweden)

    Novák Béla

    2010-10-01

    Full Text Available Abstract Background The activity of the heterodimeric transcription factor hypoxia inducible factor (HIF is regulated by the post-translational, oxygen-dependent hydroxylation of its α-subunit by members of the prolyl hydroxylase domain (PHD or EGLN-family and by factor inhibiting HIF (FIH. PHD-dependent hydroxylation targets HIFα for rapid proteasomal degradation; FIH-catalysed asparaginyl-hydroxylation of the C-terminal transactivation domain (CAD of HIFα suppresses the CAD-dependent subset of the extensive transcriptional responses induced by HIF. FIH can also hydroxylate ankyrin-repeat domain (ARD proteins, a large group of proteins which are functionally unrelated but share common structural features. Competition by ARD proteins for FIH is hypothesised to affect FIH activity towards HIFα; however the extent of this competition and its effect on the HIF-dependent hypoxic response are unknown. Results To analyse if and in which way the FIH/ARD protein interaction affects HIF-activity, we created a rate equation model. Our model predicts that an oxygen-regulated sequestration of FIH by ARD proteins significantly shapes the input/output characteristics of the HIF system. The FIH/ARD protein interaction is predicted to create an oxygen threshold for HIFα CAD-hydroxylation and to significantly sharpen the signal/response curves, which not only focuses HIFα CAD-hydroxylation into a defined range of oxygen tensions, but also makes the response ultrasensitive to varying oxygen tensions. Our model further suggests that the hydroxylation status of the ARD protein pool can encode the strength and the duration of a hypoxic episode, which may allow cells to memorise these features for a certain time period after reoxygenation. Conclusions The FIH/ARD protein interaction has the potential to contribute to oxygen-range finding, can sensitise the response to changes in oxygen levels, and can provide a memory of the strength and the duration of a

  6. Natural insertion of the bro-1 β-lactamase gene into the gatCAB operon affects Moraxella catarrhalis aspartyl-tRNA(Asn) amidotransferase activity.

    Science.gov (United States)

    Akochy, Pierre-Marie; Lapointe, Jacques; Roy, Paul H

    2012-09-01

    Only about half of bacterial species use an asparaginyl-tRNA synthetase (AsnRS) to attach Asn to its cognate tRNA(Asn). Other bacteria, including the human pathogen Moraxella catarrhalis, a causative agent of otitis media, lack a gene encoding AsnRS, and form Asn-tRNA(Asn) by an indirect pathway catalysed by two enzymes: first, a non-discriminating aspartyl-tRNA synthetase (ND-AspRS) catalyses the formation of aspartyl-tRNA(Asn) (Asp-tRNA(Asn)); then, a tRNA-dependent amidotransferase (GatCAB) transamidates this 'incorrect' product into Asn-tRNA(Asn). As M. catarrhalis has a Gln-tRNA synthetase, its GatCAB functions as an Asp-tRNA(Asn) amidotransferase. This pathogen rapidly evolved to about 90 % ampicillin resistance worldwide by insertion of a bro-1 β-lactamase gene within the gatCAB operon. Comparison of the GatCAB subunits from bro-1 β-lactamase-positive and bro-negative strains showed that the laterally transferred bro-1 gene, inserted into the gatCAB operon, affected the C-terminal sequence of GatA. The identity between the C-terminal sequences of GatA(wt) (residues 479-491) and of GatA(BRO-1) (residues 479-492) was about 36 %, whereas the rest of the GatA sequence was relatively conserved. The characterization of these two distinct GatCABs as well as the hybrid GatCAB containing GatA(1-478)(wt)(479-492)(BRO-1) and truncated GatCAB enzymes of M. catarrhalis showed that the substitution in GatA(wt) of residues 479-492 of GatA(BRO-1) causes increased specificity for glutamine, and decreased specificity for Asp-tRNA(Asn) in the transamidation reaction. We conclude that the bro gene insertion has altered the kinetic parameters of Asp-tRNA(Asn) amidotransferase, and we propose a model for gatA evolution after the insertion of bro-1 at the carboxyl end of gatA.

  7. 脯氨酸羟化酶在缺血缺氧性疾病治疗中的研究进展%Role of prolyl hydroxylases in the treatment of hypoxic-ischemic disease

    Institute of Scientific and Technical Information of China (English)

    周芳; 戴爱国; 蒋永亮; 胡瑞成; 朱黎明

    2013-01-01

    The hypoxia inducible factor (HIF) is the core factor which plays crucial role in the cellular response to the stress of hypoxia.By regulating the downstream target genes,it can maintain oxygen homeostasis.HIF prolyl hydroxylase domain containing proteins (PHDs) and asparaginyl hydroxylase (factor inhibiting HIF,FIH) are defined as cell oxygen sensors.Because the catalytic activity of these enzymes is governed by the oxygen tension within the cell.By regulating amount and transcriptional activity of HIF,they take a part in regulating O2 supply and consumption,energy conservation,O2 conformance and hypoxia tolerance and other metabolic protection mechanism.Hypoxicischemic disease is characterized by the imbalance of oxygen supply and demand.Recently,some studies found that inhibition of PHDs can strengthen the HIF signaling pathway which can play a role in the treatment and prognosis of hypoxic ischemic disease.%低氧诱导因子(hypoxia-inducible factor,HIF)是细胞低氧应答反应中的核心因子,通过对下游靶基因的调节维持氧稳态.脯氨酸羟化酶(prolyl hydroxylases,PHDs)和天冬酰胺酰羟化酶自身催化活性受细胞内氧浓度的调节被称为细胞氧感受器.它们通过调节HIF的稳定性和转录活性参与调控氧供与氧耗、能量代偿与能源补充、氧顺应性与缺氧耐受力等代谢保护机制.缺血缺氧性疾病是一类以氧的供需失衡为特点的疾病,研究发现抑制PHDs可加强HIF信号通路,在缺血缺氧性疾病的治疗和愈后中发挥作用.

  8. The midgut transcriptome of Aedes aegypti fed with saline or protein meals containing chikungunya virus reveals genes potentially involved in viral midgut escape.

    Science.gov (United States)

    Dong, Shengzhang; Behura, Susanta K; Franz, Alexander W E

    2017-05-15

    The mosquito Aedes aegypti is the primary vector for medically important arthropod-borne viruses, including chikungunya virus (CHIKV). Following oral acquisition, an arbovirus has to persistently infect several organs in the mosquito before becoming transmissible to another vertebrate host. A major obstacle an arbovirus has to overcome during its infection cycle inside the mosquito is the midgut escape barrier, representing the exit mechanism arboviruses utilize when disseminating from the midgut. To understand the transcriptomic basis of midgut escape and to reveal genes involved in the process, we conducted a comparative transcriptomic analysis of midgut samples from mosquitoes which had received a saline meal (SM) or a protein meal (PM) (not) containing CHIKV. CHIKV which was orally acquired by a mosquito along with a SM or PM productively infected the midgut epithelium and disseminated to secondary tissues. A total of 27 RNA-Seq libraries from midguts of mosquitoes that had received PM or SM (not) containing CHIKV at 1 and 2 days post-feeding were generated and sequenced. Fewer than 80 genes responded differentially to the presence of CHIKV in midguts of mosquitoes that had acquired the virus along with SM or PM. SM feeding induced differential expression (DE) of 479 genes at day 1 and 314 genes at day 2 when compared to midguts of sugarfed mosquitoes. By comparison, PM feeding induced 6029 DE genes at day 1 and 7368 genes at day 2. Twenty-three DE genes encoding trypsins, metalloproteinases, and serine-type endopeptidases were significantly upregulated in midguts of mosquitoes at day 1 following SM or PM ingestion. Two of these genes were Ae. aegypti late trypsin (AeLT) and serine collagenase 1 precursor (AeSP1). In vitro, recombinant AeLT showed strong matrix metalloproteinase activity whereas recombinant AeSP1 did not. By substituting a bloodmeal for SM, we identified midgut-expressed genes not involved in blood or protein digestion. These included genes

  9. Dynamic changes in the secondary structure of ECE-1 and XCE account for their different substrate specificities

    Directory of Open Access Journals (Sweden)

    Ul-Haq Zaheer

    2012-11-01

    Full Text Available Abstract Background X-converting enzyme (XCE involved in nervous control of respiration, is a member of the M13 family of zinc peptidases, for which no natural substrate has been identified yet. In contrast, it’s well characterized homologue endothelin-converting enzyme-1 (ECE-1 showed broad substrate specificity and acts as endopeptidase as well as dipeptidase. To explore the structural differences between XCE and ECE-1, homology model of XCE was built using the complex structure of ECE-1 with phosphoramidon (pdb-id: 3DWB as template. Phosphoramidon was docked into the binding site of XCE whereas phosphate oxygen of the inhibitor was used as water molecule to design the apo forms of both enzymes. Molecular dynamics simulation of both enzymes was performed to analyze the dynamic nature of their active site residues in the absence and presence of the inhibitor. Results Homology model of XCE explained the role of non-conserved residues of its S2’ subsite. Molecular dynamics (MD simulations identified the flexible transitions of F149/I150, N566/N571, W714/W719, and R145/R723 residues of ECE-1/XCE for the strong binding of the inhibitor. Secondary structure calculations using DSSP method reveals the folding of R145/R723 residue of ECE-1/XCE into β-sheet structure while unfolding of the S2’ subsite residues in aECE-1 and sustained compact folding of that of aXCE. The results evaluated are in good agreement with available experimental data, thus providing detailed molecular models which can explain the structural and specificities differences between both zinc peptidases. Conclusions Secondary structure changes of both enzymes during the simulation time revealed the importance of β-sheet structure of R145/R723 for its binding with the terminal carboxylate group of the inhibitor. Unfolding of the α-helix comprising the S2’ subsite residues in aECE-1 correlate well with its endopeptidase activity while their compact folding in aXCE may

  10. Enhanced activity of an angiotensin-(1-7) neuropeptidase in glucocorticoid-induced fetal programming.

    Science.gov (United States)

    Marshall, Allyson C; Shaltout, Hossam A; Pirro, Nancy T; Rose, James C; Diz, Debra I; Chappell, Mark C

    2014-02-01

    We previously identified angiotensin converting enzyme (ACE) and an endopeptidase activity that degraded angiotensin-(1-7) [Ang-(1-7)] to Ang-(1-5) and Ang-(1-4), respectively, in the cerebrospinal fluid (CSF) of 6-month old male sheep. The present study undertook a more comprehensive analysis of the CSF peptidase that converts Ang-(1-7) to Ang-(1-4) in control and in utero betamethasone-exposed sheep (BMX). Characterization of the Ang-(1-7) peptidase revealed that the thiol agents 4-aminophenylmercuric acetate (APMA) and p-chloromercuribenzoic acid (PCMB), as well as the metallo-chelators o-phenanthroline and EDTA essentially abolished the enzyme activity. Additional inhibitors for serine, aspartyl, and cysteine proteases, as well as selective inhibitors against the endopeptidases neprilysin, neurolysin, prolyl and thimet oligopeptidases did not attenuate enzymatic activity. Competition studies against the peptidase revealed similar IC50s for Ang-(1-7) (5μM) and Ang II (3μM), but lower values for Ala(1)-Ang-(1-7) and Ang-(2-7) of 1.8 and 2.0μM, respectively. In contrast, bradykinin exhibited a 6-fold higher IC50 (32μM) than Ang-(1-7) while neurotensin was a poor competitor. Mean arterial pressure (78±1 vs. 94±2mmHg, N=4-5, P<0.01) and Ang-(1-7) peptidase activity (14.2±1 vs 32±1.5fmol/min/ml CSF, N=5, P<0.01) were higher in the BMX group, and enzyme activity inversely correlated with Ang-(1-7) content in CSF. Lower Ang-(1-7) expression in brain is linked to baroreflex impairment in hypertension and aging, thus, increased activity of an Ang-(1-7) peptidase may contribute to lower CSF Ang-(1-7) levels, elevated blood pressure and impaired reflex function in this model of fetal programming.

  11. O papel das proteínas da matriz extracelular e das metaloproteinases em carcinomas de cabeça e pescoço: uma atualização bibliográfica The role of matrix extracellular proteins and metalloproteinases in head and neck carcinomas: an updated review

    Directory of Open Access Journals (Sweden)

    Antonio L.A. Pereira

    2005-02-01

    Full Text Available Interações entre células neoplásicas e constituintes da matriz extracelular (MEC interferem fortemente no desenvolvimento tumoral, incluindo os localizados em cabeça e pescoço, pois influenciam a proliferação e sobrevivência celular, bem como a sua capacidade de migrar do sítio primário para outros tecidos e formar metástases. Essa migração celular é facilitada pela destruição parcial da MEC, a qual é realizada pelas metaloproteinases (MMPs, que representam uma família de mais de vinte endopeptidases, com atividade controlada pela expressão de inibidores específicos (TIMPs. Diversos estudos utilizando-se de marcadores para constituintes da MEC bem como pelas MMPs têm fornecido informações adicionais sobre o diagnóstico e prognóstico em carcinomas de cabeça e pescoço. Nesta revisão consideraremos o papel da MEC e das MMPs na progressão desses tumores, enfatizando que não somente a degradação proteolítica está envolvida neste processo, como também interações entre vários constituintes da MEC fornecem substrato para regulação e crescimento destes tumores.Interactions involving tumor cells and the extracellular matrix (ECM strongly influence tumor development, including head and neck tumors, affecting cell proliferation and survival as well as the ability to migrate beyond the original location into other tissues to form metastases. These cell migration is often facilitated by partial destruction of the surrounding ECM, which is catalyzed by matrix metalloproteinases (MMPs, a family of more than 20 endopeptidases that is controlled by regulated expression of specific inhibitors (TIMPs. Several studies of ECM and MMPs markers have provided additional diagnostic and prognostic information in head and neck carcinomas. In this review, we are considering the role of ECM and MMPs in tumor progression, emphasizing its proteolytic contributors to this process, and interactions between several members of ECM providing

  12. Cadmium exposure inhibits MMP2 and MMP9 activities in the prostate and testis

    Energy Technology Data Exchange (ETDEWEB)

    Lacorte, Livia M.; Rinaldi, Jaqueline C.; Justulin, Luis A.; Delella, Flávia K. [Univ Estadual Paulista – UNESP, Institute of Biosciences, Department of Morphology, Extracellular Matrix Laboratory, Botucatu, SP (Brazil); Moroz, Andrei [Univ Estadual Paulista – UNESP, School of Pharmaceutical Sciences, Department of Bioprocess and Biotechnology, Cell Culture Laboratory, Araraquara, SP (Brazil); Felisbino, Sérgio L., E-mail: felisbin@ibb.unesp.br [Univ Estadual Paulista – UNESP, Institute of Biosciences, Department of Morphology, Extracellular Matrix Laboratory, Botucatu, SP (Brazil)

    2015-02-20

    Matrix metalloproteinases (MMPs) are zinc (Zn{sup 2+}) and calcium (Ca{sup 2+}) dependant endopeptidases, capable of degradation of numerous components of the extracellular matrix. Cadmium (Cd{sup 2+}) is a well known environmental contaminant which could impair the activity of MMPs. In this sense, this study was conducted to evaluate if Cd{sup 2+} intake inhibits these endopeptidases activities at the rat prostate and testicles and if it directly inhibits the activity of MMP2 and MMP9 at gelatinolytic assays when present in the incubation buffer. To investigate this hypothesis, Wistar rats (5 weeks old), were given tap water (untreated, n = 9), or 15 ppm CdCl{sub 2} diluted in drinking water, during 10 weeks (n = 9) and 20 weeks (n = 9). The animals were euthanized and their ventral prostate, dorsal prostate, and testicles were removed. These tissue samples were processed for protein extraction and subjected to gelatin zymography evaluation. Additionally, we performed an experiment of gelatin zymography in which 5 μM or 2 mM cadmium chloride (CdCl{sub 2}) was directly dissolved at the incubation buffer, using the prostatic tissue samples from untreated animals that exhibited the highest MMP2 and MMP9 activities in the previous experiment. We have found that CdCl{sub 2} intake in the drinking water led to the inhibition of 35% and 30% of MMP2 and MMP9 (p < 0.05) at the ventral prostate and testis, respectively, in Cd{sup 2+} treated animals when compared to controls. Moreover, the activities of the referred enzymes were 80% and 100% inhibited by 5 μM and 2 mM of CdCl{sub 2}, respectively, even in the presence of 10 mM of CaCl{sub 2} within the incubation buffer solution. These important findings demonstrate that environmental cadmium contamination may deregulate the natural balance in the extracellular matrix turnover, through MMPs downregulation, which could contribute to the toxic effects observed in prostatic and testicular tissue after its

  13. 重组内肽酶AspN的原核表达纯化和活性鉴定%Cloning,Expression,Purification and Characterization of Soluble Recombinant Endoproteainase AspN

    Institute of Scientific and Technical Information of China (English)

    郑娟; 郭怀祖; 李晶; 段树燕; 赵自叶; 张大鹏; 郭尚敬; 王皓

    2015-01-01

    Endoproteinase AspN(flavastacin)is a zinc metalloendopeptidase which can selectively cleave peptide bonds N-terminal to aspartic acid residues, also it is one of most widely used proteolytic enzyme used for protein digestion prior to MS or HPLC analysis. The natural endoproteinase AspN was extract from the bacteria,Elizabethkingia meningoseptica. Some factors including low yields, difficulty in purification and high cost, greatly limit the application of the enzyme. Target gene was cloned into an pET32a expression vector and transformed into E.coli BL21(DE3). This is the first report for the soluble expression of AspN-Trx in prokaryotic expression system and a poly-histidine tag enabled purification by Ni affinity chromatography. The activity of the recombinant endopeptidase AspN was identified by HPLC, SDS-PAGE and the fluorogenic substrate Anthranilyl-Ala-Phe-Ala-Phe-Asp-Val-Phe(NO2)-Tyr-Asp. The results showed that the recombinant endopeptidase AspN was consistent with the standard enzyme and can be used widely.%蛋白内肽酶AspN是一种锌金属内切肽酶,能选择性切割天冬氨酸的N端肽键,广泛应用于蛋白的多肽制备及质量肽图谱鉴定。目前内肽酶AspN来源于细菌分泌,产量低,制备困难,成本高,极大地限制了该酶的应用。将脑膜脓毒性黄杆菌分泌的蛋白内肽酶AspN所对应的基因克隆入表达载体pET32a,导入E.coli BL21(DE3),首次运用原核表达系统进行可溶性融合表达,亲和层析对重组蛋白进行纯化。用HPLC、SDS-PAGE和荧光底物Anthranilyl-Ala-Phe-Ala-Phe-Asp-Val-Phe(NO2)-Tyr-Asp对重组酶进行酶活鉴定。结果表明重组的内肽酶AspN具有与标准品基本一致的酶切活性,能够较好地应用于生物和制药领域。

  14. Identification of key peptidoglycan hydrolases for morphogenesis, autolysis, and peptidoglycan composition of Lactobacillus plantarum WCFS1

    Directory of Open Access Journals (Sweden)

    Rolain Thomas

    2012-10-01

    Full Text Available Abstract Background Lactobacillus plantarum is commonly used in industrial fermentation processes. Selected strains are also marketed as probiotics for their health beneficial effects. Although the functional role of peptidoglycan-degrading enzymes is increasingly documented to be important for a range of bacterial processes and host-microbe interactions, little is known about their functional roles in lactobacilli. This knowledge holds important potential for developing more robust strains resistant to autolysis under stress conditions as well as peptidoglycan engineering for a better understanding of the contribution of released muramyl-peptides as probiotic immunomodulators. Results Here, we explored the functional role of the predicted peptidoglycan hydrolase (PGH complement encoded in the genome of L. plantarum by systematic gene deletion. From twelve predicted PGH-encoding genes, nine could be individually inactivated and their corresponding mutant strains were characterized regarding their cell morphology, growth, and autolysis under various conditions. From this analysis, we identified two PGHs, the predicted N-acetylglucosaminidase Acm2 and NplC/P60 D,L-endopeptidase LytA, as key determinants in the morphology of L. plantarum. Acm2 was demonstrated to be required for the ultimate step of cell separation of daughter cells, whereas LytA appeared to be required for cell shape maintenance and cell-wall integrity. We also showed by autolysis experiments that both PGHs are involved in the global autolytic process with a dominant role for Acm2 in all tested conditions, identifying Acm2 as the major autolysin of L. plantarum WCFS1. In addition, Acm2 and the putative N-acetylmuramidase Lys2 were shown to play redundant roles in both cell separation and autolysis under stress conditions. Finally, the analysis of the peptidoglycan composition of Acm2- and LytA-deficient derivatives revealed their potential hydrolytic activities by the

  15. Sjcb2 DNA疫苗的构建及其在真核细胞中的表达%Construction of Sjcb2 DNA vaccine and its expression in eukaryotic cells

    Institute of Scientific and Technical Information of China (English)

    胡永轩; 肖建华; 黄家芳; 杨秋林

    2006-01-01

    Objective To clone and construct the recombinant plasmid containing cathepsin B endopeptidase of Schistosomajaponicum (Sjcb2) and transfer it into mammalian cells to express Cathepsin B endopeptidase protein. Methods By polymerasechain reaction(PCR) tenique, Sjcb2 was amplified from the constructed recombinant plasmid pBC SK +/Sjcb2. Followly Sjcb2 wasinserted into cloning vector pUCm - T. Then Sjcb2 was subcloned to the eukaryotic expression vector pcDNA3.1 ( + ) by linking reactions. After identifying it by PCR,restrietive enzymes digestion and DNA sequencing, the recombinant plamid was transfected into HeLa cells using electroporation, and analyze the expression of the recombinant protein by indirect immunofluorescence assay. Results The specific gene fragment about 1047bp was successfully amplified. The DNA vaccine of Sjcb2 was successfully constructed.Indirect immunofluorescence assay showed that Sjcb2 was expressed in HeLa cells and located in cytoplasm. Conclusion Sjcb2gene can be expressed in eukaryotic system, which lay the foundation for studying the pathogenic mechanism and the development ofthe Sjcb2 DNA vaccine against Schitosomiasis.%目的克隆日本血吸虫组织蛋白酶B基因,构建真核表达重组质粒,转染真核细胞,观察其表达情况.方法用PCR技术从已构建好的重组质粒pBC SK+/Sjcb2中扩增出Sjcb2基因片段,重组入克隆载体pUCm-T.再将Sjcb2基因片段亚克隆入真核表达载体pcDNA3.1(+).进行PCR、双酶切和DNA序列鉴定后,运用电穿孔技术将重组体pcDNA3.1(+)/Sjcb2转染HeLa细胞,间接免疫荧光技术观察目的基因的表达. 结果成功扩增出Sjcb2基因片段并构建DNA疫苗;重组质粒在HeLa细胞中获得表达.结论Sjcb2基因能够在体外真核细胞中表达.

  16. [New approach in the research of analgesics and antihypertensive agents].

    Science.gov (United States)

    Roques, B P

    1991-01-01

    The activation or interruption of the responses induced by regulatory peptides are ensured by ectoenzymes, the most important of them belonging to the group of zinc metallopeptidases. Thus angiotensin converting enzyme (ACE) forms the hypertensive peptide angiotensin II from its inactive precursor AI. This also the case for aminopeptidase N (APN) and neutral endopeptidase 24.11 (NEP, CALLA) which together inactivate the endogenous opioid peptides, enkephalins, whereas only NEP is involved in the metabolism of the atrial natriuretic factor (ANP) at the kidney and vascular levels. The pharmacological effects resulting from the inhibition of these enzymatic processes will appear only in tissues where the peptide substrate is tonically or phasically released. This promising approach is expected to avoid, or at least to minimize, the side effects resulting from excessive and ubiquitous stimulation of peptide receptors by exogenously administered agonists or antagonists. The essential amino acids known to be present in the active site of the bacterial endopeptidase thermolysin from crystallographic studies, have also been found in NEP by using a new program of sequence comparison associated with mutagenesis experiments. Several classes of selective inhibitors of NEP, APN and ACE have been rationally designed by taking into account the structural differences in the active site of these peptidases. Thus, the retro-inversion of the amide bond of the NEP inhibitor thiorphan resulted in the elimination of a residual interaction with ACE. Moreover, we have proposed to associate inhibitory potencies towards two peptidases in the same compound. Thus kelatorphan HONH-CO-CH2-CH(CH2 phi)-CONH-CH(CH3)-COOH and other systemically-active mixed NEP/APN inhibitors were shown capable of completely blocking enkephalin metabolism in vivo. This concept has been extended to mixed NEP/ACE inhibitors with compounds such as HS-CH2-CH(CH2 phi)-CONH-CH(CH2R)-COOH where R = CH-(CH3)2 (ES 34) or

  17. Effects of pirfenidone on increased cough reflex sensitivity in guinea pigs.

    Science.gov (United States)

    Okazaki, Akihito; Ohkura, Noriyuki; Fujimura, Masaki; Katayama, Nobuyuki; Kasahara, Kazuo

    2013-10-01

    Pirfenidone, an antifibrotic drug with anti-inflammatory and antioxidant effects, delays fibrosis in idiopathic pulmonary fibrosis (IPF). Patients with IPF have a greater cough reflex sensitivity to inhaled capsaicin than healthy people, and cough is an independent predictor of IPF disease progression; however, the effects of pirfenidone on cough reflex sensitivity are unknown. After challenge with an aerosolized antigen in actively sensitized guinea pigs, pirfenidone was administered intraperitoneally, and the cough reflex sensitivity was measured at 48 h after the challenge. Bronchoalveolar lavage (BAL) was performed, and the tracheal tissue was collected. Pirfenidone suppressed the capsaicin-induced increase in cough reflex sensitivity in a dose-dependent manner. Additionally, increased levels of prostaglandin E2, substance P, and leukotriene B4, but not histamine, in the BAL fluid were dose dependently suppressed by pirfenidone. The decrease in neutral endopeptidase activity in the tracheal tissue was also alleviated by pirfenidone treatment. The total number of cells and components in the BAL fluid was not influenced. These results suggest that pirfenidone ameliorates isolated cough based on increased cough reflex sensitivity associated with allergic airway diseases, and potentially relieve chronic cough in IPF patients who often have increased cough reflex sensitivity. Prospective studies on cough-relieving effects of pirfenidone in patients with IPF are therefore warranted.

  18. Abundant class III acidic chitinase homologue in tamarind (Tamarindus indica) seed serves as the major storage protein.

    Science.gov (United States)

    Rao, Devavratha H; Gowda, Lalitha R

    2008-03-26

    The phyla Leguminosae contains protease inhibitors, lectins, chitinases, and glycohydrolases as major defense proteins in their seeds. Electrophoretic analysis of the seed proteins of tamarind ( Tamarindus indica L.), an agri-waste material, indicated the unusual presence of two major proteins comparable to overexpression of recombinant proteins. These proteins were identified by amino-terminal analysis to be (1) Kunitz-type trypsin inhibitor and (2) class III endochitinase (34000 Da). These two proteins were purified to apparent homogeneity by a single-step chitin bead affinity chromatography and characterized. The Kunitz inhibitor was specific toward inhibiting trypsin with a stoichiometry of 1:1. The 33000 +/- 1000 Da protein, accounting for >50% of the total seed protein, is an acidic glycoprotein exhibiting a very low endotype hydrolytic activity toward chitin derivatives. SDS-PAGE followed by densitometry of tamarind seed germination indicates the disappearance of the chitinase with the concomitant appearance of a cysteine endopeptidase. On the basis of its abundance, accumulation without any pathogenesis-related stimulus, temporal regulation, amino acid composition, and very low enzyme activity, this 34000 Da protein designated "tamarinin" physiologically serves as the major storage protein.

  19. In vitro detection and quantification of botulinum neurotoxin type E activity in avian blood

    Science.gov (United States)

    Piazza, Timothy M.; Blehert, David S.; Dunning, F. Mark; Berlowski-Zier, Brenda M.; Zeytin, Fusun N.; Samuel, Michael D.; Tucker, Ward C.

    2011-01-01

    Botulinum neurotoxin serotype E (BoNT/E) outbreaks in the Great Lakes region cause large annual avian mortality events, with an estimated 17,000 bird deaths reported in 2007 alone. During an outbreak investigation, blood collected from bird carcasses is tested for the presence of BoNT/E using the mouse lethality assay. While sensitive, this method is labor-intensive and low throughput and can take up to 7 days to complete. We developed a rapid and sensitive in vitro assay, the BoTest Matrix E assay, that combines immunoprecipitation with high-affinity endopeptidase activity detection by Förster resonance energy transfer (FRET) to rapidly quantify BoNT/E activity in avian blood with detection limits comparable to those of the mouse lethality assay. On the basis of the analysis of archived blood samples (n = 87) collected from bird carcasses during avian mortality investigations, BoTest Matrix E detected picomolar quantities of BoNT/E following a 2-h incubation and femtomolar quantities of BoNT/E following extended incubation (24 h) with 100% diagnostic specificity and 91% diagnostic sensitivity.

  20. Bacterial protease triggered release of biocides from microspheres with an oily core.

    Science.gov (United States)

    Craig, Marina; Amiri, Mona; Holmberg, Krister

    2015-03-01

    This study deals with controlled release of drugs to a Staphylococcus aureus infected site from microspheres with an oily core and a polymeric shell. The intended use of the microspheres is for chronic wounds and the microspheres may be administered in the form of a wash liquid or incorporated in a gel. Chronic wounds often carry infection, and the use of microspheres with drug release triggered by the bacterial infection is therefore of interest. A lipophilic drug or a model of the drug was dissolved in an oil and the oil phase was dispersed into an o/w emulsion. A nanofilm shell was then assembled around the oil droplets with the layer-by-layer technique using the two biodegradable polypeptides anionic poly-L-glutamic acid (PLGA) and cationic poly-L-lysine (PLL). Since S. aureus exudes proteases such as glutamyl endopeptidase (V8) during colonization and infection, its substrate specificity was key when assembling the nanofilm. Since V8 is known to be substrate specific to the Glu-X bond, PLGA was chosen as the terminating layer of the nanofilm. Crosslinking the nanofilm after assembly lead to increased stability of the microspheres. It was shown that in a non-infectious environment, i.e. when a human wound enzyme, HNE (human neutrophile elastase), was present, the microspheres remained intact. The staphylococcal protease V8, on the other hand, readily catalyzed degradation of the microspheres, thus releasing the drug when triggered by the infectious environment.

  1. Identification of liver protein targets modified by tienilic acid metabolites using a two-dimensional Western blot-mass spectrometry approach

    Science.gov (United States)

    Methogo, Ruth Menque; Dansette, Patrick M.; Klarskov, Klaus

    2007-12-01

    A combined approach based on two-dimensional electrophoresis-immuno-blotting and nanoliquid chromatography coupled on-line with electrospray ionization mass spectrometry (nLC-MS/MS) was used to identify proteins modified by a reactive intermediate of tienilic acid (TA). Liver homogenates from rats exposed to TA were fractionated using ultra centrifugation; four fractions were obtained and subjected to 2D electrophoresis. Following transfer to PVDF membranes, modified proteins were visualized after India ink staining, using an anti-serum raised against TA and ECL detection. Immuno-reactive spots were localized on the PVDF membrane by superposition of the ECL image, protein spots of interest were excised, digested on the membrane with trypsin followed by nLC-MS/MS analysis and protein identification. A total of 15 proteins were identified as likely targets modified by a TA reactive metabolite. These include selenium binding protein 2, senescence marker protein SMP-30, adenosine kinase, Acy1 protein, adenosylhomocysteinase, capping protein (actin filament), protein disulfide isomerase, fumarylacetoacetase, arginase chain A, ketohexokinase, proteasome endopeptidase complex, triosephosphate isomerase, superoxide dismutase, dna-type molecular chaperone hsc73 and malate dehydrogenase.

  2. Characterization of a juvenile hormone-regulated chymotrypsin-like serine protease gene in Aedes aegypti mosquito.

    Science.gov (United States)

    Bian, Guowu; Raikhel, Alexander S; Zhu, Jinsong

    2008-02-01

    After female mosquitoes ingest blood from vertebrate hosts, exopeptidases and endopeptidases are required for digesting blood proteins in the midgut into amino acids, which female mosquitoes use to build yolk proteins. These proteases are not always present in the midgut, and their diverse expression patterns suggest that production of these enzymes is highly regulated in order to meet specific physiological demands at various stages. Here we report identification of a serine-type protease, JHA15, in the yellow fever mosquito Aedes aegypti. This protein shares high sequence homology with chymotrypsins, and indeed exhibits specific chymotrypsin enzymatic activity. The JHA15 gene is expressed primarily in the midgut of adult female mosquitoes. Our results indicate that its transcription is activated by juvenile hormone in the newly emerged female adults. Although its mRNA profile is similar to that of the early trypsin gene, we found that JHA15 proteins were readily detected in the midgut epithelium cells of both non-blood-fed and blood-fed mosquitoes. Analysis of polysomal RNA further substantiated that synthesis of JHA15 occurs before and shortly after blood feeding. Knocking down expression of JHA15 resulted in no evident phenotypic changes, implying that functional redundancy exists among those proteolytic enzymes.

  3. Gene cloning and biochemical characterization of eryngase, a serine aminopeptidase of Pleurotus eryngii belonging to the family S9 peptidases.

    Science.gov (United States)

    Arima, Jiro; Tokai, Shota; Chiba, Masanori; Ichiyanagi, Tsuyoshi; Yabuta, Yukinori; Mori, Nobuhiro; Aimi, Tadanori

    2014-01-01

    Pleurotus eryngii serine aminopeptidase that has peptide bond formation activity, redesignated as eryngase, was cloned and expressed. Eryngase has a family S9 peptidase unit in the C-terminal region having a catalytic triad of Ser, Asp, and His. In the phylogenetic relations among the subfamilies of family S9 peptidase (S9A, prolyl oligopeptidase; S9B, dipeptidyl peptidase; S9C, acylaminoacyl peptidase; S9D, glutamyl endopeptidase), eryngase existed alone in the neighbor of S9C subfamily. Mutation of the active site Ser524 of the eryngase with Ala eliminated its catalytic activity. In contrast, S524C mutant maintained low catalytic activity. Investigation of aminolysis activity using l-Phe-NH2 as a substrate showed that S524C mutant exhibited no hydrolysis reaction but synthesized a small amount of l-Phe-l-Phe-NH2 by the catalysis of aminolysis. In contrast, wild-type eryngase hydrolyzed the product of aminolysis l-Phe-l-Phe-NH2. Results show that the S524C mutant preferentially catalyzed aminolysis when on an l-Phe-NH2 substrate.

  4. The application of the fibroblast activation protein α-targeted immunotherapy strategy.

    Science.gov (United States)

    Jiang, Guan-Min; Xu, Wei; Du, Jun; Zhang, Kun-Shui; Zhang, Qiu-Gui; Wang, Xiao-Wei; Liu, Zhi-Gang; Liu, Shuang-Quan; Xie, Wan-Ying; Liu, Hui-Fang; Liu, Jing-Shi; Wu, Bai-Ping

    2016-05-31

    Cancer immunotherapy has primarily been focused on attacking tumor cells. However, given the close interaction between tumor cells and cancer-associated fibroblasts (CAFs) in the tumor microenvironment (TME), CAF-targeted strategies could also contribute to an integrated cancer immunotherapy. Fibroblast activation protein α (FAP α) is not detectible in normal tissues, but is overexpressed by CAFs and is the predominant component of the stroma in most types of cancer. FAP α has both dipeptidyl peptidase and endopeptidase activities, cleaving substrates at a post-proline bond. When all FAP α-expressing cells (stromal and cancerous) are destroyed, tumors rapidly die. Furthermore, a FAP α antibody, FAP α vaccine, and modified vaccine all inhibit tumor growth and prolong survival in mouse models, suggesting FAP α is an adaptive tumor-associated antigen. This review highlights the role of FAP α in tumor development, explores the relationship between FAP α and immune suppression in the TME, and discusses FAP α as a potential immunotherapeutic target.

  5. Fiscal 1997 R and D project on industrial science and technology under a consignment form NEDO. R and D of the technology of accelerated formation of bio-functions; 1997 nendo sangyo kagaku gijutsu kenkyu kaihatsu jigyo Shin energy Sangyo Gijutsu Sogo Kaihatsu Kiko itaku. Kasokugata seibutsu kino kochiku gijutsu no kenkyu kaihatsu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    As a part of the study on accelerated formation of bio- functions, analysis technology of experimental systems for in vitro evolution of protein molecules was studied. For the analysis, recognition of a fitness landscape is indispensable. Improvement of adaptive walk is possible through its analysis in an ordered space based on features of the landscape. By the last fiscal year, the knowledge of the fitness (heat-stability) landscape was obtained in the experimental system of PEP (prolyl endopeptidase) in which an adaptive walk mechanism was found to function effectively (mutated protein with a heat-stability effectively improved by adaptive walk was obtained). To obtain more general fitness landscape information, landscapes of various proteins to a fitness should be examined, and the effectiveness of approaches to efficient adaptive walk on the fitness other than a heat-stability should be clarified. The second experimental system using LOD (lactate oxidase) was thus constructed to examine the heat-stability landscape. In addition, the system of in vitro molecular evolution of proteinase inhibitor (Cystatin B) was constructed. 3 refs., 3 figs., 2 tabs.

  6. The research progress and clinical application of human CD10 molecule%CD10分子的研究进展及临床应用

    Institute of Scientific and Technical Information of China (English)

    刘芸; 廖晓龙

    2014-01-01

    CD10分子最初作为普通急性淋巴细胞白血病抗原(CALLA)被发现,是一个相对分子质量为90 000-110 000Ⅱ型单链穿膜糖蛋白.CD10分子广泛分布在各种组织,具有中性肽链内切酶(NEP)的功能,并且表达在不同的组织,其功能不尽相同.目前广泛应用于用血液系统肿瘤以及部分实体肿瘤的诊断和预后判断,还用于造血细胞分化发育研究和部分组织干细胞的研究.%Human CD10 molecul,which was found as the common acute lymphoblastic leukemia anti-gen (CALLA),is a type Ⅱ single-chain transmembrane glycoprotein (90 000-110 000),expressed broadly on varied tissues.CD10 is a neutral endopeptidase (NEP),and it performs different function in different organs.Anti CD10 antibodies are used for the detection and prognosis of leukemia and solid tumor,as well as for research in hematopoietic and tissue stem cells.

  7. A Novel PHEX Mutation in Japanese Patients with X-Linked Hypophosphatemic Rickets

    Directory of Open Access Journals (Sweden)

    Tetsuya Kawahara

    2015-01-01

    Full Text Available X-linked hypophosphatemic rickets (XLH is a dominant inherited disorder characterized by renal phosphate wasting, aberrant vitamin D metabolism, and abnormal bone mineralization. Inactivating mutations in the gene encoding phosphate-regulating gene with homologies to endopeptidases on the X chromosome (PHEX have been found to be associated with XLH. Here, we report a 16-year-old female patient affected by hypophosphatemic rickets. We evaluated her serum fibroblast growth factor 23 (FGF23 levels and conducted sequence analysis of the disease-associated genes of FGF23-related hypophosphatemic rickets: PHEX, FGF23, dentin matrix protein 1, and ectonucleotide pyrophosphatase/phosphodiesterase 1. She was diagnosed with XLH based on her clinical features and family history. Additionally, we observed elevated FGF23 levels and a novel PHEX exon 9 mutation (c.947G>T; p.Gly316Val inherited from her father. Although bioinformatics showed that the mutation was neutral, Gly316 is perfectly conserved among humans, mice, and rats, and there were no mutations in other FGF23-related rickets genes, suggesting that in silico analysis is limited in determining mutation pathogenicity. In summary, we present a female patient and her father with XLH harboring a novel PHEX mutation that appears to be causative of disease. Measurement of FGF23 for hypophosphatemic patients is therefore useful for the diagnosis of FGF23-dependent hypophosphatemia.

  8. The Rachitic Tooth

    Science.gov (United States)

    Nociti, Francisco H.; Somerman, Martha J.

    2014-01-01

    Teeth are mineralized organs composed of three unique hard tissues, enamel, dentin, and cementum, and supported by the surrounding alveolar bone. Although odontogenesis differs from osteogenesis in several respects, tooth mineralization is susceptible to similar developmental failures as bone. Here we discuss conditions fitting under the umbrella of rickets, which traditionally referred to skeletal disease associated with vitamin D deficiency but has been more recently expanded to include newly identified factors involved in endocrine regulation of vitamin D, phosphate, and calcium, including phosphate-regulating endopeptidase homolog, X-linked, fibroblast growth factor 23, and dentin matrix protein 1. Systemic mineral metabolism intersects with local regulation of mineralization, and factors including tissue nonspecific alkaline phosphatase are necessary for proper mineralization, where rickets can result from loss of activity of tissue nonspecific alkaline phosphatase. Individuals suffering from rickets often bear the additional burden of a defective dentition, and transgenic mouse models have aided in understanding the nature and mechanisms involved in tooth defects, which may or may not parallel rachitic bone defects. This report reviews dental effects of the range of rachitic disorders, including discussion of etiologies of hereditary forms of rickets, a survey of resulting bone and tooth mineralization disorders, and a discussion of mechanisms, known and hypothesized, involved in the observed dental pathologies. Descriptions of human pathology are augmented by analysis of transgenic mouse models, and new interpretations are brought to bear on questions of how teeth are affected under conditions of rickets. In short, the rachitic tooth will be revealed. PMID:23939820

  9. [Anti-NEP and anti-PLA2R antibodies in membranous nephropathy: an update].

    Science.gov (United States)

    Pozdzik, A A; Debiec, H; I Brochériou; Husson, C; Rorive, S; Broeders, N; Le Moine, A; Ronco, P; Nortier, J

    2015-01-01

    Membranous nephropathy (MN) is the most common cause for nephrotic syndrome in adults and occurs as an idiopathic (primary) or secondary disease. Since the early 2000's, substantial advances have been made in the understanding of the molecular bases of MN. The neutral endopeptidase (NEP) and the receptor for secretory phospholipase A2 (PLA2R) have been identified as target antigens for circulating and deposited antibodies in allo-immune neonatal and adult " idiopathic " MN, respectively. These antibodies recognize specific antigens of podocytes, precipitate as subepithelial immune complexes and activate complement leading to proteinuria. Anti-PLA2R antibodies are of particular clinical importance. Indeed, they are detected in approximately 70% of primary MN in adults, demonstrating that MN actually is an autoimmune condition specific to the kidney. In Europeans, genome-wide studies have shown an association between alleles of PLA2R1 and HLA DQA1 (class II genes of tissue histocompatibility complex) genes and idiopathic MN. Newly developed diagnostic tests detecting circulating anti-PLA2R antibody and PLA2R antigen in glomerular deposits have induced a change in paradigm in the diagnostic approach of idiopathic MN. Measurement of circulating anti-PLA2R antibody is also very useful for the monitoring of MN activity. However, the mechanisms responsible for the formation of anti-PLA2R antibodies as well as those involved in the progression of MN to end-stage renal disease remain to be defined.

  10. Pathophysiological advances in membranous nephropathy: time for a shift in patient's care.

    Science.gov (United States)

    Ronco, Pierre; Debiec, Hanna

    2015-05-16

    Membranous nephropathy is a major cause of nephrotic syndrome of non-diabetic origin in adults. It is the second or third leading cause of end-stage renal disease in patients with primary glomerulonephritis, and is the leading glomerulopathy that recurs after kidney transplantation (occurring in about 40% of patients). Treatment with costly and potentially toxic drugs remains controversial and challenging, partly because of insufficient insight into the pathogenesis of the disease and absence of sensitive biomarkers of disease activity. The disease is caused by the formation of immune deposits on the outer aspect of the glomerular basement membrane, which contain podocyte or planted antigens and circulating antibodies specific to those antigens, resulting in complement activation. In 2002, podocyte neutral endopeptidase was identified as an antigenic target of circulating antibodies in alloimmune neonatal nephropathy, and in 2009, podocyte phospholipase A2 receptor (PLA2R) was reported as an antigenic target in autoimmune adult membranous nephropathy. These major breakthroughs were translated to clinical practice very quickly. Measurement of anti-PLA2R antibodies in serum and detection of PLA2R antigen in glomerular deposits can now be done routinely. Anti-PLA2R antibodies have high specificity (close to 100%), sensitivity (70-80%), and predictive value. PLA2R detection in immune deposits allows for retrospective diagnosis of PLA2R-related membranous nephropathy in archival kidney biopsies. These tests already have a major effect on diagnosis and monitoring of treatment, including after transplantation.

  11. Matrix metalloproteinases in the brain and blood-brain barrier: Versatile breakers and makers.

    Science.gov (United States)

    Rempe, Ralf G; Hartz, Anika Ms; Bauer, Björn

    2016-09-01

    Matrix metalloproteinases are versatile endopeptidases with many different functions in the body in health and disease. In the brain, matrix metalloproteinases are critical for tissue formation, neuronal network remodeling, and blood-brain barrier integrity. Many reviews have been published on matrix metalloproteinases before, most of which focus on the two best studied matrix metalloproteinases, the gelatinases MMP-2 and MMP-9, and their role in one or two diseases. In this review, we provide a broad overview of the role various matrix metalloproteinases play in brain disorders. We summarize and review current knowledge and understanding of matrix metalloproteinases in the brain and at the blood-brain barrier in neuroinflammation, multiple sclerosis, cerebral aneurysms, stroke, epilepsy, Alzheimer's disease, Parkinson's disease, and brain cancer. We discuss the detrimental effects matrix metalloproteinases can have in these conditions, contributing to blood-brain barrier leakage, neuroinflammation, neurotoxicity, demyelination, tumor angiogenesis, and cancer metastasis. We also discuss the beneficial role matrix metalloproteinases can play in neuroprotection and anti-inflammation. Finally, we address matrix metalloproteinases as potential therapeutic targets. Together, in this comprehensive review, we summarize current understanding and knowledge of matrix metalloproteinases in the brain and at the blood-brain barrier in brain disorders.

  12. Aminopeptidase activity from germinated jojoba cotyledons.

    Science.gov (United States)

    Johnson, R; Storey, R

    1985-11-01

    One major and two minor aminopeptidase activities from germinated jojoba (Simmondsia chinensis) cotyledon extracts were separated by ammonium sulfate precipitation and chromatofocusing. None of the activities were inhibited by 1,10 phenanthroline.The major aminopeptidase, purified 260-fold, showed a pH optimum of 6.9 with leucine-p-nitroanilide as substrate, a molecular weight estimated at 14,200 by electrophoretic analysis, and an isoelectric point of 4.5 according to the chromatofocusing pattern. Activity was inhibited by p-chloromercuribenzoate, slightly stimulated by 1,10 phenanthroline and 2-mercaptoethanol, and not influenced by Mg(2+) or diethyl pyrocarbonate. Inhibition by p-chloromercuribenzoate was prevented by the presence of cysteine in the assay. Leucine-p-nitroanilide and leucine-beta-naphthylamide were the most rapidly hydrolyzed of 11 carboxy-terminal end blocked synthetic substrates tested. No activity on endopeptidase or carboxypeptidase specific substrates was detected. The major aminopeptidase showed activity on a saline soluble, jojoba seed protein preparation and we suggest a possible physiological role for the enzyme in the concerted degradation of globulin reserve proteins during cotyledon senescence.

  13. Degradation of proteins by enzymes exuded by Allium porrum roots - a potentially important strategy for acquiring organic nitrogen by plants.

    Science.gov (United States)

    Adamczyk, Bartosz; Godlewski, Mirosław; Smolander, Aino; Kitunen, Veikko

    2009-10-01

    Nitrogen is one of the crucial elements that regulate plant growth and development. It is well-established that plants can acquire nitrogen from soil in the form of low-molecular-mass compounds, namely nitrate and ammonium, but also as amino acids. Nevertheless, nitrogen in the soil occurs mainly as proteins or proteins complexed with other organic compounds. Proteins are believed not to be available to plants. However, there is increasing evidence to suggest that plants can actively participate in proteolysis by exudation of proteases by roots and can obtain nitrogen from digested proteins. To gain insight into the process of organic nitrogen acquisition from proteins by leek roots (Allium porrum L. cv. Bartek), casein, bovine serum albumin and oxidized B-chain of insulin were used; their degradation products, after exposure to plant culture medium, were studied using liquid chromatography-mass spectrometry (LC-MS). Casein was degraded to a great extent, but the level of degradation of bovine serum albumin and the B-chain of insulin was lower. Proteases exuded by roots cleaved proteins, releasing low-molecular-mass peptides that can be taken up by roots. Various peptide fragments produced by digestion of the oxidized B-chain of insulin suggested that endopeptidase, but also exopeptidase activity was present. After identification, proteases were similar to cysteine protease from Arabidopsis thaliana. In conclusion, proteases exuded by roots may have great potential in the plant nitrogen nutrition.

  14. Phosphatonins: physiological role and pathological changes

    Science.gov (United States)

    Cavalli, Loredana; Mazzotta, Celestina; Brandi, Maria Luisa

    2012-01-01

    Summary Maintenance of proper serum phosphate concentrations is required for healthy life, and critical for normal skeletal development and integrity. Several hormones and regulatory factors such as vitamin D, parathyroid hormone (PTH), and the phosphatonins (FGF-23, sFRP-4, MEPE) among others, may play a role only in the long-term regulation of phosphorus homeostasis. FGF23 is part of a previously unrecognized hormonal bone-parathyroid-kidney axis. Its synthesis and secretion by osteocytes are positively regulated by 1,25(OH)2D and serum phosphorus and negatively by the phosphate-regulating gene with homologies to endopeptidases on the X chromosome (PHEX), and the enzyme N-acetyl galactosamine trasferase 3 (PPGGalNacT3), encoded by GALnT3 gene, prevents its degradation. FGF23 requires Klotho protein as a coreceptor for high affinity binding to cognate FGF receptors (FGFRs). Mutations of any of FGF23, Klotho or GALnT3 genes can lead to a syndrome characterized by hyperphosphatemia, ectopic calcifications and recurrent long bone lesions with hyperostosis. Phosphatonin have been shown to be implicated in several common diseases involving kidney and mineral metabolism. FGF23 might also represent a promising putative marker for bone healing. PMID:22783327

  15. Acute and chronic respiratory lesions induced by sulfur mustard in guinea pigs: Role of tachykinins

    Energy Technology Data Exchange (ETDEWEB)

    Calvet, J.H.; Trouiller, G.; Harf, A.

    1993-05-13

    We investigated in anesthetized guinea pigs the involvement of tachykinins in respiratory alterations after an airway intoxication by sulfur mustard (SM). Early lesions were evaluated after 5h. Respiratory system resistance (R) and compliance were measured by the occlusion method and airway microvascular permeability by measuring the Evans Blue dye concentration in the trachea and main bronchi. Two groups of animals were studied treated with capsaicin (which induces a tachykinin depletion) or by its vehicle. Capsaicin pretreatment had no effect on the measured parameters. We also measured 14 J after the intoxication tracheal epithelium neutral endopeptidase (NEP) (the main enzyme which degrades tachykinins). In addition bronchial responsiveness to exogenous substance P was studied in two groups of animals intoxicated with SM or not. Tracheal epithelium NEP activity was decreased from 0.448 + or 0.027 nmol.min- 1.mg protein- 1 in controls to 0. 182 + or 0.038 in intoxicated animals. Response to substance P was greater in intoxicated animals with R=2.98 + or - 1.57 cmH20.MI-1.s versus 0.35 + or 0.02 in controls, after 5.10-5 M aerosolized substance P These results suggest tachykinins are not preponderant in the early stage lesions but that bronchial hyperactivity is present at recovery, related to epithelium NEP depletion.

  16. Vasopeptidase inhibition improves insulin sensitivity and endothelial function in the JCR:LA-cp rat.

    Science.gov (United States)

    Russell, James C; Kelly, Sandra E; Schäfer, Stefan

    2004-08-01

    The insulin-resistant, hyperinsulinemic, normoglycemic, and obese JCR:LA-cp rat was used to study the effects of ramipril (an ACE inhibitor) and AVE7688 (a dual inhibitor of ACE and neutral endopeptidases) on insulin sensitivity and vascular function. Both compounds reduced the surge of plasma insulin in a meal tolerance test by approximately 50%. Ramipril had no effect on acetylcholine-induced relaxation but increased the sensitivity to sodium nitroprus-side at low concentrations. AVE7688 significantly reduced the EC50 for acetylcholine to relax phenylephrine-contracted aortic rings. None of the compounds affected the baseline coronary flow and reactive hyperemia. Coronary flow response to bradykinin in AVE7688- and ramipril-treated rat hearts showed a significantly lower EC50 than in control rats. Maximum flow rate was not different between groups. In summary, both ramipril and AVE7688 had significant hypoinsulinemic and insulin-sensitizing effects. Whereas ramipril had limited vascular effects, AVE7688 had more marked beneficial vascular effects, probably of endothelial origin and possibly related to lowered insulin levels.

  17. Purification, cDNA cloning, and recombinant expression of chymotrypsin C from porcine pancreas

    Institute of Scientific and Technical Information of China (English)

    Haibo Wang; Duoduo Yuan; Rong Xu; Cheng-Wu Chi

    2011-01-01

    Chymotrypsin C is a bifunctional secretory-type serine protease in pancreas; besides proteolytical activity, it also exhibits a calcium-decreasing activity in serum, In this study, we purified activated chymotrypsin C from porcine pancreas, and identified its three active forms. Active chymotrypsin C was found to be different in the length of its 13-residue activation peptide due to carboxydipeptidase (present in the pancreas) degradation or autolysis of the activated chymotrypsin C itself, resulting in the removal of several C-terminus residues from the activation peptide. After limited chymotrypsin C cleavage with endopeptidase Lys C, several purified peptides were partially sequenced, and the entire cDNA sequence for porcine chymotrypsin C was cloned. Recombinant chymotrypsinogen C was successfully expressed in Escherichia coli cells as inclusion bodies. After refolding and activation with trypsin, the comparison of the recombinant chymotrypsin C with the natural form showed that their proteolytic and calcium-decreasing activities were at the same level. The successful expression of chymotrypsin C gene paves the way to further mutagenic structurefunction studies.

  18. A LysM and SH3-domain containing region of the Listeria monocytogenes p60 protein stimulates accessory cells to promote activation of host NK cells.

    Science.gov (United States)

    Schmidt, Rebecca L; Filak, Holly C; Lemon, Jack D; Potter, Terry A; Lenz, Laurel L

    2011-11-01

    Listeria monocytogenes (Lm) infection induces rapid and robust activation of host natural killer (NK) cells. Here we define a region of the abundantly secreted Lm endopeptidase, p60, that potently but indirectly stimulates NK cell activation in vitro and in vivo. Lm expression of p60 resulted in increased IFNγ production by naïve NK cells co-cultured with treated dendritic cells (DCs). Moreover, recombinant p60 protein stimulated activation of naive NK cells when co-cultured with TLR or cytokine primed DCs in the absence of Lm. Intact p60 protein weakly digested bacterial peptidoglycan (PGN), but neither muropeptide recognition by RIP2 nor the catalytic activity of p60 was required for NK cell activation. Rather, the immune stimulating activity mapped to an N-terminal region of p60, termed L1S. Treatment of DCs with a recombinant L1S polypeptide stimulated them to activate naïve NK cells in a cell culture model. Further, L1S treatment activated NK cells in vivo and increased host resistance to infection with Francisella tularensis live vaccine strain (LVS). These studies demonstrate an immune stimulating function for a bacterial LysM domain-containing polypeptide and suggest that recombinant versions of L1S or other p60 derivatives can be used to promote NK cell activation in therapeutic contexts.

  19. A LysM and SH3-domain containing region of the Listeria monocytogenes p60 protein stimulates accessory cells to promote activation of host NK cells.

    Directory of Open Access Journals (Sweden)

    Rebecca L Schmidt

    2011-11-01

    Full Text Available Listeria monocytogenes (Lm infection induces rapid and robust activation of host natural killer (NK cells. Here we define a region of the abundantly secreted Lm endopeptidase, p60, that potently but indirectly stimulates NK cell activation in vitro and in vivo. Lm expression of p60 resulted in increased IFNγ production by naïve NK cells co-cultured with treated dendritic cells (DCs. Moreover, recombinant p60 protein stimulated activation of naive NK cells when co-cultured with TLR or cytokine primed DCs in the absence of Lm. Intact p60 protein weakly digested bacterial peptidoglycan (PGN, but neither muropeptide recognition by RIP2 nor the catalytic activity of p60 was required for NK cell activation. Rather, the immune stimulating activity mapped to an N-terminal region of p60, termed L1S. Treatment of DCs with a recombinant L1S polypeptide stimulated them to activate naïve NK cells in a cell culture model. Further, L1S treatment activated NK cells in vivo and increased host resistance to infection with Francisella tularensis live vaccine strain (LVS. These studies demonstrate an immune stimulating function for a bacterial LysM domain-containing polypeptide and suggest that recombinant versions of L1S or other p60 derivatives can be used to promote NK cell activation in therapeutic contexts.

  20. Soluble expression and purification of receptor activator of nuclear factor-kappa B ligand using Escherichia coli.

    Science.gov (United States)

    Park, Sol-Ji; Lee, Se-Hoon; Kim, Kwang-Jin; Kim, Sung-Gun; Kim, Hangun; Choe, Han; Lee, Sang Yeol; Yun, Jung-Mi; Cho, Jae Youl; Chun, Jiyeon; Choi, Kap Seong; Son, Young-Jin

    2015-02-01

    Receptor activator of nuclear factor-kappa B ligand (RANKL) is a critical factor in osteoclastogenesis. It makes osteoclasts differentiate and multinucleate in bone remodeling. In the present study, RANKL was expressed as a soluble maltose binding protein (MBP)-fusion protein using the Escherichia coli maltose binding domain tag system (pMAL) expression vector system. The host cell E. coli DH5α was cultured and induced by isopropyl β-D-1- thiogalactopyranoside for rRANKL expression. Cells were disrupted by sonication to collect soluble MBP-fused rRANKL. The MBP-fusion rRANKL was purified with MBP Trap affinity chromatography and treated with Tobacco Etch Virus nuclear inclusion endopeptidase (TEV protease) to remove the MBP fusion protein. Dialysis was then carried out to remove binding maltose from the cleaved rRANKL solution. The cleaved rRANKL was purified with a second MBP Trap affinity chromatography to separate unsevered MBP-fusion rRANKL and cleaved MBP fusion protein. The purified rRANKL was shown to have biological activity by performing in vitro cell tests. In conclusion, biologically active rRANKL was successfully purified by a simple two-step chromatography purification process with one column.

  1. Progress in research on bacteriophage lysins%噬菌体裂解酶的研究进展

    Institute of Scientific and Technical Information of China (English)

    张瑞安; 刘军; 冯书章

    2012-01-01

    噬菌体裂解酶是噬菌体在感染细菌后期表达的一类细胞壁水解酶,具有酶活性和底物特异性.多数噬菌体具有编码3种细胞壁水解酶即溶菌酶、酰胺酶和内肽酶的基因.本文综述了噬菌体裂解酶重组及其应用的研究,并探讨了近年来重组裂解酶的研究进展.%Bacteriophage lysins are cell wall lytic enzymes expressed in the late phase of bacterial infection,with enzyme activity and substrate specificity. Most of bacteriophages contain the genes encoding three kinds of cell wall lytic enzymes,i.e. lysozyme,N-acetylmuramoyl-L-alanine amidase and endopeptidases. This paper reviews the recombination and application of bacteriophage lysins as well as the progress in research on recombinant lysins in recent years.

  2. Novel and unique diagnostic biomarkers for Bacillus anthracis infection.

    Science.gov (United States)

    Sela-Abramovich, Sagit; Chitlaru, Theodor; Gat, Orit; Grosfeld, Haim; Cohen, Ofer; Shafferman, Avigdor

    2009-10-01

    A search for bacterium-specific biomarkers in peripheral blood following infection with Bacillus anthracis was carried out with rabbits, using a battery of specific antibodies generated by DNA vaccination against 10 preselected highly immunogenic bacterial antigens which were identified previously by a genomic/proteomic/serologic screen of the B. anthracis secretome. Detection of infection biomarkers in the circulation of infected rabbits could be achieved only after removal of highly abundant serum proteins by chromatography using a random-ligand affinity column. Besides the toxin component protective antigen, the following three secreted proteins were detected in the circulation of infected animals: the chaperone and protease HtrA (BA3660), an NlpC/P60 endopeptidase (BA1952), and a protein of unknown function harboring two SH3 (Src homology 3) domains (BA0796). The three proteins could be detected in plasma samples from infected animals exhibiting 10(3) to 10(5) CFU/ml blood and also in standard blood cultures at 3 to 6 h post-bacterial inoculation at a bacteremic level as low as 10(3) CFU/ml. Furthermore, the three biomarkers appear to be present only in the secretome of B. anthracis, not in those of the related pathogens B. thuringiensis and B. cereus. To the best of our knowledge, this is the first report of direct detection of B. anthracis-specific proteins, other than the toxin components, in the circulation of infected animals.

  3. A Label Free Colorimetric Assay for the Detection of Active Botulinum Neurotoxin Type A by SNAP-25 Conjugated Colloidal Gold

    Directory of Open Access Journals (Sweden)

    Christopher Gwenin

    2013-08-01

    Full Text Available Botulinum neurotoxins are one of the most potent toxins known to man. Current methods of detection involve the quantification of the toxin but do not take into account the percentage of the toxin that is active. At present the assay used for monitoring the activity of the toxin is the mouse bioassay, which is lengthy and has ethical issues due to the use of live animals. This report demonstrates a novel assay that utilises the endopeptidase activity of the toxin to detect Botulinum neurotoxin in a pharmaceutical sample. The cleaving of SNAP-25 is monitored via UV-Visible spectroscopy with a limit of detection of 373 fg/mL and has been further developed into a high throughput method using a microplate reader detecting down to 600 fg/mL of active toxin. The results show clear differences between the toxin product and the placebo, which contains the pharmaceutical excipients human serum albumin and lactose, showing that the assay detects the active form of the toxin.

  4. Recent patents on microbial proteases for the dairy industry.

    Science.gov (United States)

    Feijoo-Siota, Lucía; Blasco, Lucía; Rodríguez-Rama, José Luis; Barros-Velázquez, Jorge; Miguel, Trinidad de; Sánchez-Pérez, Angeles; Villa, Tomás G

    2014-01-01

    This paper reviews the general characteristics of exo and endopeptidases of microbial origin currently used in the milk industry. It also includes recent patents developed either to potentiate the enzymatic activity or to improve the resulting milk derivatives. The main application of these proteases is in the cheese-making industry. Although this industry preferentially uses animal rennets, and in particular genetically engineered chymosins, it also utilizes milk coagulants of microbial origin. Enzymes derived from Rhizomucor miehei, Rhizomucor pusillus and Cryphonectria parasitica are currently used to replace the conventional milk-clotting enzymes. In addition, the dairy industry uses microbial endo and exoproteases for relatively new applications, such as debittering and flavor generation in cheese, accelerated cheese ripening, manufacture of protein hydrolysates with improved functional properties, and production of enzyme-modified cheeses. Lactic acid bacteria play an essential role in these processes, hence these bacteria and the proteases they produce are currently being investigated by the dairy industry and are the subject of many of their patent applications.

  5. Matrix metalloproteinases in neural development: a phylogenetically diverse perspective

    Science.gov (United States)

    Small, Christopher D.; Crawford, Bryan D.

    2016-01-01

    The matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases originally characterized as secreted proteases responsible for degrading extracellular matrix proteins. Their canonical role in matrix remodelling is of significant importance in neural development and regeneration, but emerging roles for MMPs, especially in signal transduction pathways, are also of obvious importance in a neural context. Misregulation of MMP activity is a hallmark of many neuropathologies, and members of every branch of the MMP family have been implicated in aspects of neural development and disease. However, while extraordinary research efforts have been made to elucidate the molecular mechanisms involving MMPs, methodological constraints and complexities of the research models have impeded progress. Here we discuss the current state of our understanding of the roles of MMPs in neural development using recent examples and advocate a phylogenetically diverse approach to MMP research as a means to both circumvent the challenges associated with specific model organisms, and to provide a broader evolutionary context from which to synthesize an understanding of the underlying biology. PMID:27127457

  6. Experimental Dissection of Metalloproteinase Inhibition-Mediated and Toxic Effects of Phenanthroline on Zebrafish Development

    Directory of Open Access Journals (Sweden)

    Tonya R. Ellis

    2016-09-01

    Full Text Available Metalloproteinases are zinc-dependent endopeptidases that function as primary effectors of tissue remodeling, cell-signaling, and many other roles. Their regulation is ferociously complex, and is exquisitely sensitive to their molecular milieu, making in vivo studies challenging. Phenanthroline (PhN is an inexpensive, broad-spectrum inhibitor of metalloproteinases that functions by chelating the catalytic zinc ion, however its use in vivo has been limited due to suspected off-target effects. PhN is very similar in structure to phenanthrene (PhE, a well-studied poly aromatic hydrocarbon (PAH known to cause toxicity in aquatic animals by activating the aryl hydrocarbon receptor (AhR. We show that zebrafish are more sensitive to PhN than PhE, and that PhN causes a superset of the effects caused by PhE. Morpholino knock-down of the AhR rescues the effects of PhN that are shared with PhE, suggesting these are due to PAH toxicity. The effects of PhN that are not shared with PhE (specifically disruption of neural crest development and angiogenesis involve processes known to depend on metalloproteinase activity. Furthermore these PhN-specific effects are not rescued by AhR knock-down, suggesting that these are bona fide effects of metalloproteinase inhibition, and that PhN can be used as a broad spectrum metalloproteinase inhibitor for studies with zebrafish in vivo.

  7. Experimental Dissection of Metalloproteinase Inhibition-Mediated and Toxic Effects of Phenanthroline on Zebrafish Development

    Science.gov (United States)

    Ellis, Tonya R.; Crawford, Bryan D.

    2016-01-01

    Metalloproteinases are zinc-dependent endopeptidases that function as primary effectors of tissue remodeling, cell-signaling, and many other roles. Their regulation is ferociously complex, and is exquisitely sensitive to their molecular milieu, making in vivo studies challenging. Phenanthroline (PhN) is an inexpensive, broad-spectrum inhibitor of metalloproteinases that functions by chelating the catalytic zinc ion, however its use in vivo has been limited due to suspected off-target effects. PhN is very similar in structure to phenanthrene (PhE), a well-studied poly aromatic hydrocarbon (PAH) known to cause toxicity in aquatic animals by activating the aryl hydrocarbon receptor (AhR). We show that zebrafish are more sensitive to PhN than PhE, and that PhN causes a superset of the effects caused by PhE. Morpholino knock-down of the AhR rescues the effects of PhN that are shared with PhE, suggesting these are due to PAH toxicity. The effects of PhN that are not shared with PhE (specifically disruption of neural crest development and angiogenesis) involve processes known to depend on metalloproteinase activity. Furthermore these PhN-specific effects are not rescued by AhR knock-down, suggesting that these are bona fide effects of metalloproteinase inhibition, and that PhN can be used as a broad spectrum metalloproteinase inhibitor for studies with zebrafish in vivo. PMID:27618022

  8. Inhibition of serotonin release by bombesin-like peptides in rat hypothalamus in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Saporito, M.S.; Warwick, R.O. Jr.

    1989-01-01

    We investigated the activity of bombesin (BN), neuromedin-C (NM-C) and neuromedin-B (NM-B) on serotonin (5-HT) release and reuptake in rat hypothalamus (HYP) in vitro. BN and NM-C but not NM-B decreased K/sup +/ evoked /sup 3/H-5-HT release from superfused HYP slices by 25%. Bacitracin, a nonspecific peptidase inhibitor, reversed the inhibitory effect of BN on K/sup +/ evoked /sup 3/H-5-HT release. Phosphoramidon (PAN, 10 /mu/M) an endopeptidase 24.11 inhibitor, abolished the inhibitory effect of BN, but not NM-C, on K/sup +/ evoked /sup 3/H-5-HT release. The peptidyl dipeptidase A inhibitor enalaprilat (ENP, 10 /mu/M), enhanced both BN and NM-C inhibition of /sup 3/H-5-HT release. Bestatin (BST, 10 /mu/M) had no effect on BN or NM-C inhibitory activity on /sup 3/H-5-HT release. Neither BN, NM-C nor NM-B affected reuptake of /sup 3/H-5-HT into HYP synaptosomes alone or in combination with any of the peptidase inhibitors, nor did these peptides alter the ability of fluoxetine to inhibit /sup 3/H-5-HT uptake.

  9. CHANGES IN LEVELS OF ACTIVITY OF SERINE PROTEASES ACCOMPANY THE EXPOSURE OF COMMON BEAN (PHASEOLUS VULGARIS L. TO WATER DEFICIT

    Directory of Open Access Journals (Sweden)

    M. Budič

    2008-09-01

    Full Text Available A wide variety of proteolytic enzymes exist in plants. On their levels depends protein turnover, a fundamental component in plant development and adaptation to environmental conditions. Cysteine proteases have frequently been reported to be influenced by drought, but only a few serine proteases (SP, among them the trypsin-like enzyme and two aminopeptidases from bean leaves (Bartels and Sunkar, 2005; Hieng et al., 2004. Our starting point was to identify proteolytic activities assigned to SPs that change with drought and then to characterize the corresponding proteases. A quantitative, analytical one-step method was used to separate endopeptidases and aminopeptidases active against a range of substrates in leaf extracts of plants grown in the field (FC. The influence of drought was determined for those of these activities which were confirmed as SPs, based on their inhibition by specific inhibitors. Under water deficit in plants grown under controlled conditions (CC their levels changed in different ways. The levels of SP activities in FC plants, observed during a period of relative drought, were similar to those measured in mildly stressed CC plants. The partial characterisations of some of these SPs will be presented. Our results point to a number of roles for different SPs in the plant response to water stress, which could range from enhanced protein turnover to limited proteolysis at specific sites.

  10. Enhanced Peptide Stability Against Protease Digestion Induced by Intrinsic Factor Binding of a Vitamin B12 Conjugate of Exendin-4.

    Science.gov (United States)

    Bonaccorso, Ron L; Chepurny, Oleg G; Becker-Pauly, Christoph; Holz, George G; Doyle, Robert P

    2015-09-08

    Peptide digestion from proteases is a significant limitation in peptide therapeutic development. It has been hypothesized that the dietary pathway of vitamin B12 (B12) may be exploited in this area, but an open question is whether B12-peptide conjugates bound to the B12 gastric uptake protein intrinsic factor (IF) can provide any stability against proteases. Herein, we describe a new conjugate of B12 with the incretin peptide exendin 4 that demonstrates picomolar agonism of the glugacon-like peptide-1 receptor (GLP1-R). Stability studies reveal that Ex-4 is digested by pancreatic proteases trypsin and chymotrypsin and by the kidney endopeptidase meprin β. Prebinding the B12 conjugate to IF, however, resulted in up to a 4-fold greater activity of the B12-Ex-4 conjugate relative to Ex-4, when the IF-B12-Ex-4 complex was exposed to 22 μg/mL of trypsin, 2.3-fold greater activity when exposed to 1.25 μg/mL of chymotrypsin, and there was no decrease in function at up to 5 μg/mL of meprin β.

  11. Substance P promotes wound healing in diabetes by modulating inflammation and macrophage phenotype.

    Science.gov (United States)

    Leal, Ermelindo C; Carvalho, Eugénia; Tellechea, Ana; Kafanas, Antonios; Tecilazich, Francesco; Kearney, Cathal; Kuchibhotla, Sarada; Auster, Michael E; Kokkotou, Efi; Mooney, David J; LoGerfo, Frank W; Pradhan-Nabzdyk, Leena; Veves, Aristidis

    2015-06-01

    Diabetic foot ulceration is a major complication of diabetes. Substance P (SP) is involved in wound healing, but its effect in diabetic skin wounds is unclear. We examined the effect of exogenous SP delivery on diabetic mouse and rabbit wounds. We also studied the impact of deficiency in SP or its receptor, neurokinin-1 receptor, on wound healing in mouse models. SP treatment improved wound healing in mice and rabbits, whereas the absence of SP or its receptor impaired wound progression in mice. Moreover, SP bioavailability in diabetic skin was reduced as SP gene expression was decreased, whereas the gene expression and protein levels of the enzyme that degrades SP, neutral endopeptidase, were increased. Diabetes and SP deficiency were associated with absence of an acute inflammatory response important for wound healing progression and instead revealed a persistent inflammation throughout the healing process. SP treatment induced an acute inflammatory response, which enabled the progression to the proliferative phase and modulated macrophage activation toward the M2 phenotype that promotes wound healing. In conclusion, SP treatment reverses the chronic proinflammatory state in diabetic skin and promotes healing of diabetic wounds.

  12. Matrix metalloproteinases in wound repair (review).

    Science.gov (United States)

    Ravanti, L; Kähäri, V M

    2000-10-01

    Wound repair is initiated with the aggregation of platelets, formation of a fibrin clot, and release of growth factors from the activated coagulation pathways, injured cells, platelets, and extracellular matrix (ECM), followed by migration of inflammatory cells to the wound site. Thereafter, keratinocytes migrate over the wound, angiogenesis is initiated, and fibroblasts deposit and remodel the granulation tissue. Cell migration, angiogenesis, degradation of provisional matrix, and remodeling of newly formed granulation tissue, all require controlled degradation of the ECM. Disturbance in the balance between ECM production and degradation leads to formation of chronic ulcers with excessive ECM degradation, or to fibrosis, for example hypertrophic scars or keloids characterized by excessive accumulation of ECM components. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases, which as a group can degrade essentially all ECM components. So far, 20 members of the human MMP family have been identified. Based on their structure and substrate specificity, they can be divided into subgroups of collagenases, stromelysins, stromelysin-like MMPs, gelatinases, membrane-type MMPs (MT-MMPs), and other MMPs. In this review, the role of MMPs in normal wound repair as well as in chronic ulcers is discussed. In addition, the role of signaling pathways, in particular, mitogen-activated protein kinases (MAPKs) in regulating MMP expression is discussed as possible therapeutical targets for wound healing disorders.

  13. Structural basis for Ca2+-independence and activation by homodimerization of tomato subtilase 3.

    Science.gov (United States)

    Ottmann, Christian; Rose, Rolf; Huttenlocher, Franziska; Cedzich, Anna; Hauske, Patrick; Kaiser, Markus; Huber, Robert; Schaller, Andreas

    2009-10-06

    Subtilases are serine proteases found in Archae, Bacteria, yeasts, and higher eukaryotes. Plants possess many more of these subtilisin-like endopeptidases than animals, e.g., 56 identified genes in Arabidopsis compared with only 9 in humans, indicating important roles for subtilases in plant biology. We report the first structure of a plant subtilase, SBT3 from tomato, in the active apo form and complexed with a chloromethylketone (cmk) inhibitor. The domain architecture comprises an N-terminal protease domain displaying a 132 aa protease-associated (PA) domain insertion and a C-terminal seven-stranded jelly-roll fibronectin (Fn) III-like domain. We present the first structural evidence for an explicit function of PA domains in proteases revealing a vital role in the homo-dimerization of SBT3 and in enzyme activation. Although Ca(2+)-binding sites are conserved and critical for stability in other subtilases, SBT3 was found to be Ca(2+)-free and its thermo stability is Ca(2+)-independent.

  14. Properties and Therapeutic Application of Bromelain: A Review

    Directory of Open Access Journals (Sweden)

    Rajendra Pavan

    2012-01-01

    Full Text Available Bromelain belongs to a group of protein digesting enzymes obtained commercially from the fruit or stem of pineapple. Fruit bromelain and stem bromelainare prepared differently and they contain different enzymatic composition. “Bromelain” refers usually to the “stem bromelain.” Bromelain is a mixture of different thiol endopeptidases and other components like phosphatase, glucosidase, peroxidase, cellulase, escharase, and several protease inhibitors. In vitro and in vivo studies demonstrate that bromelain exhibits various fibrinolytic, antiedematous, antithrombotic, and anti-inflammatory activities. Bromelain is considerably absorbable in the body without losing its proteolytic activity and without producing any major side effects. Bromelain accounts for many therapeutic benefits like the treatment of angina pectoris, bronchitis, sinusitis, surgical trauma, and thrombophlebitis, debridement of wounds, and enhanced absorption of drugs, particularly antibiotics. It also relieves osteoarthritis, diarrhea, and various cardiovascular disorders. Bromelain also possesses some anticancerous activities and promotes apoptotic cell death. This paper reviews the important properties and therapeutic applications of bromelain, along with the possible mode of action.

  15. Purificação de bromelina dos resíduos de abacaxi (Ananas comosus L. Merril por sistemas bifásicos aquosos PEG/Sal

    Directory of Open Access Journals (Sweden)

    Diego de Freitas Coelho

    2011-01-01

    Full Text Available Due to the dimension of worldwide production of pineapple and to high amount of generated waste from its cultivation and processing, several research have been developed to recovery the enzymes presents on pineapple, such as bromelain. Bromelain is the general name given to the group of endopeptidases found in pineapple as well as all proteases derived from members of the family Bromeliaceae, which belongs to the pineapple. Because of that play important physiological roles, these enzymes offers a wide range of proven therapeutic applications. This work aims the purification of bromelain from pineapple waste through PEG/Salt aqueous two-phase systems (ATPS using (NH42SO4, CaCl2 and potassium phosphate. The results showed that in CaCl2 experiments have no ATPS formation in the range of its constituents. However, the PEG/phosphate systems and PEG/(NH42SO4 systems showed excellent results, recovering with bromelain purification factor of 7.4 and 10.7 times, respectively, and yields above 80%.

  16. Genetic Testing Confirmed the Early Diagnosis of X-Linked Hypophosphatemic Rickets in a 7-Month-Old Infant

    Directory of Open Access Journals (Sweden)

    Kok Siong Poon BSc

    2015-08-01

    Full Text Available Loss-of-function mutations in the phosphate regulating gene with homologies to endopeptidases on the X-chromosome (PHEX have been causally associated with X-linked hypophosphatemic rickets (XLHR. The early diagnosis of XLHR in infants is challenging when it is based solely on clinical features and biochemical findings. We report a 7-month-old boy with a family history of hypophosphatemic rickets., who demonstrated early clinical evidence of rickets, although serial biochemical findings could not definitively confirm rickets. A sequencing assay targeting the PHEX gene was first performed on the mother’s DNA to screen for mutations in the 5′UTR, 22 coding exons, and the exon-intron junctions. Targeted mutation analysis and mRNA studies were subsequently performed on the boys’ DNA to investigate the pathogenicity of the identified mutation. Genetic screening of the PHEX gene revealed a novel mutation, c.1080-2A>C, at the splice acceptor site in intron 9. The detection of an aberrant mRNA transcript with skipped (loss of exon 10 establishes its pathogenicity and confirms the diagnosis of XLHR in this infant. Genetic testing of the PHEX gene resulted in early diagnosis of XLHR, thus enabling initiation of therapy and prevention of progressive rachitic changes in the infant.

  17. cDNA cloning of the murine PEX gene implicated in X-linked hypophosphatemia and evidence for expression in bone

    Energy Technology Data Exchange (ETDEWEB)

    Du, L.; Desbarats, M.; Viel, J. [McGill Univ., Montreal, Quebec (Canada)] [and others

    1996-08-15

    The recently identified human PEX g ene apparently encodes for a neutral endopeptidase that is mutated in patients with X-linked hypophosphatemia. The 3{prime} and 5{prime} ends of the coding region of PEX have not been cloned, nor has the tissue expression of the gene been identified. Here we report the isolation and characterization of the complete open reading frame of the mouse Pex gene and the demonstration of its expression in bone. Mouse Pex cDNA is predicted to encode a protein of 749 amino acids with 95% identity to the available human PEX sequence and significant homology to members of the membrane-bound metalloendopeptidase family. Northern blot analysis revealed a 6.6-kb transcript in bone and in cultured osteoblasts from normal mice that was not detectable in samples from the Hyp mouse, the murine homolog of human X-linked hypophosphatemia. Pex transcripts were, however, detectable in Hyp bone by RT-PCR amplification. Of particular interest, a cDNA clone from rat incisor shows 93% sequence identity to the 5{prime} end of Pex cDNA, suggesting that Pex may be expressed in another calcified tissue, the tooth. The association of impaired mineralization of bone and teeth and disturbed renal phosphate reabsorption with altered expression of Pex suggests that the Pex gene product may play a critical role in these processes. 47 refs., 2 figs., 1 tab.

  18. Casodex treatment induces hypoxia-related gene expression in the LNCaP prostate cancer progression model

    Directory of Open Access Journals (Sweden)

    Gopalakrishnan Velliyur K

    2005-03-01

    Full Text Available Abstract Background The changes in gene expression profile as prostate cancer progresses from an androgen-dependent disease to an androgen-independent disease are still largely unknown. Methods We examined the gene expression profile in the LNCaP prostate cancer progression model during chronic treatment with Casodex using cDNA microarrays consisting of 2305 randomly chosen genes. Results Our studies revealed a representative collection of genes whose expression was differentially regulated in LNCaP cells upon treatment with Casodex. A set of 15 genes were shown to be highly expressed in Casodex-treated LNCaP cells compared to the reference sample. This set of highly expressed genes represents a signature collection unique to prostate cancer since their expression was significantly greater than that of the collective pool of ten cancer cell lines of the reference sample. The highly expressed signature collection included the hypoxia-related genes membrane metallo-endopeptidase (MME, cyclin G2, and Bcl2/adenovirus E1B 19 kDa (BNIP3. Given the roles of these genes in angiogenesis, cell cycle regulation, and apoptosis, we further analyzed their expression and concluded that these genes may be involved in the molecular changes that lead to androgen-independence in prostate cancer. Conclusion Our data indicate that one of the mechanisms of Casodex action in prostate cancer cells is induction of hypoxic gene expression.

  19. The complete amino acid sequence of growth hormone of an elasmobranch, the blue shark (Prionace glauca).

    Science.gov (United States)

    Yamaguchi, K; Yasuda, A; Lewis, U J; Yokoo, Y; Kawauchi, H

    1989-02-01

    The complete amino acid sequence of growth hormone (GH) from a phylogenetically ancient fish, the blue shark (Prionace glauca), was determined. The shark GH isolated from pituitary glands by U. J. Lewis, R. N. P. Singh, B. K. Seavey, R. Lasker, and G. E. Pickford (1972, Fish. Bull. 70, 933-939) was purified by reversed-phase high-performance liquid chromatography. The hormone was reduced, carboxymethylated, and subsequently cleaved in turn with cyanogen bromide and Staphylococcus aureus protease. The intact protein was also cleaved with lysyl endopeptidase and o-iodosobenzoic acid. The resulting peptide fragments were separated by rpHPLC and submitted to sequence analysis by automated and manual Edman methods. The shark GH consists of 183 amino acid residues with a calculated molecular weight of 21,081. Sequence comparisons revealed that the elasmobranch GH is considerably more similar to tetrapod GHs (e.g., 68% identity with sea turtle GH, 63% with chicken GH, and 58% with ovine GH) than teleostean GHs (e.g., 38% identities with salmon GH and 42% with bonito GH) except for eel GH (61% identity), and substantiates the earlier finding derived from the immunochemical and biological studies (Hayashida and Lewis, 1978) that the primitive fish are less diverged from the main line of vertebrate evolution leading to the tetrapod than are the modern bony fish.

  20. Toxicological effects and risk assessment of lanthanum ions on leaves of Viciafaba L.seedlings

    Institute of Scientific and Technical Information of China (English)

    WANG Ning; WANG Chengrun; BAO Xia; LI Yueyun; TIAN Liumin; ZOU Huixian; WANG Xiaorong

    2011-01-01

    Viciafaba L.seedlings were hydroponically cultivated in 0-12 mg/L of extraneous lanthanum (La) for 15 d to investigate ecotoxicological effects and risk assessment of rare earth elements (REEs).The results showed that reactive oxygen species (ROS) production such as superoxide radical (O2-) and hydrogen peroxide (H2O2) were overproduced at higher concentrations of La,resulting in oxidatively modified proteins and shoot growth retardation.While,superoxide dismutase (SOD),catalase (CAT),ascorbate peroxidase (APX) and guaiacol peroxidase (GPX) isoenzymes were elevated to some extent to eliminate excess of ROS.HSP70 production and endopeptidase isoenzymes were also enhanced,which were involved in repairing or degradation of the oxidatively modified proteins due to La.Thus,the antioxidant isoenzymes,endoprotease isoenzymes and HSP70 worked cooperatively to alleviate the La-induced oxidative damage.The significant enhancement of CAT and APX isoenzymes and HSP70 could also be used as early bioindicators of La-polluted solution.The threshold dose range was firstly delimited as 1-2 mg/L of extraneous La,corresponding to 7.34-9.37 μg/g dry weight in the leaves.These results would be helpful to further understand the toxicological effects and possible mechanisms of REE(s) on crop seedlings.

  1. Expression of IgA Proteases by Haemophilus influenzae in the Respiratory Tract of Adults With Chronic Obstructive Pulmonary Disease.

    Science.gov (United States)

    Murphy, Timothy F; Kirkham, Charmaine; Jones, Megan M; Sethi, Sanjay; Kong, Yong; Pettigrew, Melinda M

    2015-12-01

    Immunoglobulin (Ig)A proteases of Haemophilus influenzae are highly specific endopeptidases that cleave the hinge region of human IgA1 and also mediate invasion and trafficking in human respiratory epithelial cells, facilitating persistence of H. influenzae. Little is known about the expression of IgA proteases in clinical settings of H. influenzae infection. We identified and characterized IgA protease genes in H. influenzae and studied their expression and proteolytic specificity, in vitro and in vivo in 169 independent strains of H. influenzae collected longitudinally over 10 years from adults with chronic obstructive pulmonary disease. The H. influenzae pangenome has 2 alleles of IgA protease genes; all strains have igaA, and 40% of strains have igaB. Each allele has 2 variants with differing proteolytic specificities for human IgA1. A total of 88% of 169 strains express IgA protease activity. Expression of the 4 forms of IgA protease varies among strains. Based on the presence of IgA1 fragments in sputum samples, each of the different forms of IgA protease is selectively expressed in the human airways during infection. Four variants of IgA proteases are variably expressed by H. influenzae during infection of the human airways. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  2. Matrix metalloproteinases regulate the formation of dendritic spine head protrusions during chemically induced long-term potentiation.

    Directory of Open Access Journals (Sweden)

    Zsuzsanna Szepesi

    Full Text Available Dendritic spines are are small membranous protrusions that extend from neuronal dendrites and harbor the majority of excitatory synapses. Increasing evidence has shown that matrix metalloproteinases (MMPs, a family of extracellularly acting and Zn(2+-dependent endopeptidases, are able to rapidly modulate dendritic spine morphology. Spine head protrusions (SHPs are filopodia-like processes that extend from the dendritic spine head, representing a form of postsynaptic structural remodeling in response to altered neuronal activity. Herein, we show that chemically induced long-term potentiation (cLTP in dissociated hippocampal cultures upregulates MMP-9 activity that controls the formation of SHPs. Blocking of MMPs activity or microtubule dynamics abolishes the emergence of SHPs. In addition, autoactive recombinant MMP-9, promotes the formation of SHPs in organotypic hippocampal slices. Furthermore, spines with SHPs gained postsynaptic α-amino-3-hydroxyl-5-methyl-4-isoxazole propionic acid (AMPA receptors upon cLTP and the synaptic delivery of AMPA receptors was controlled by MMPs. The present results strongly imply that MMP-9 is functionally involved in the formation of SHPs and the control of postsynaptic receptor distribution upon cLTP.

  3. Suppression of Tumor Growth in Mice by Rationally Designed Pseudopeptide Inhibitors of Fibroblast Activation Protein and Prolyl Oligopeptidase

    Directory of Open Access Journals (Sweden)

    Kenneth W. Jackson

    2015-01-01

    Full Text Available Tumor microenvironments (TMEs are composed of cancer cells, fibroblasts, extracellular matrix, microvessels, and endothelial cells. Two prolyl endopeptidases, fibroblast activation protein (FAP and prolyl oligopeptidase (POP, are commonly overexpressed by epithelial-derived malignancies, with the specificity of FAP expression by cancer stromal fibroblasts suggesting FAP as a possible therapeutic target. Despite overexpression in most cancers and having a role in angiogenesis, inhibition of POP activity has received little attention as an approach to quench tumor growth. We developed two specific and highly effective pseudopeptide inhibitors, M83, which inhibits FAP and POP proteinase activities, and J94, which inhibits only POP. Both suppressed human colon cancer xenograft growth >90% in mice. By immunohistochemical stains, M83- and J94-treated tumors had fewer microvessels, and apoptotic areas were apparent in both. In response to M83, but not J94, disordered collagen accumulations were observed. Neither M83- nor J94-treated mice manifested changes in behavior, weight, or gastrointestinal function. Tumor growth suppression was more extensive than noted with recently reported efforts by others to inhibit FAP proteinase function or reduce FAP expression. Diminished angiogenesis and the accompanying profound reduction in tumor growth suggest that inhibition of either FAP or POP may offer new therapeutic approaches that directly target TMEs.

  4. Proteinase K activity determination with β-galactosidase as sensitive macromolecular substrate.

    Science.gov (United States)

    Ghéczy, Nicolas; Küchler, Andreas; Walde, Peter

    2016-11-15

    Proteinase K from Engyodontium album (proK) is a relatively unspecific serine endopeptidase which is known to attack proteins yet in their native states. If the attacked protein is an enzyme, even a partial hydrolysis by proK may lead to an inactivation of the enzyme, which can be monitored by measuring the loss of catalytic activity of the attacked enzyme. E. coli β-galactosidase (β-Gal) was used in this work as such enzyme. It was found to be a convenient and sensitive macromolecular model substrate for comparing the "native protein-attacking ability" of free and immobilized proK at pH = 7.0 and 23 °C. The β-Gal activity was measured spectrophotometrically with o-nitrophenyl-β-galactopyranoside. Reproducible proK determinations were possible for as little as 4.3 ng proK by using a proK analyte solution of 10 nM. Compared to free proK, immobilized proK was much less efficient in inactivating β-Gal, most likely due to a decreased mobility of immobilized proK and a restricted accessibility of β-Gal to the active site of proK. Worth noting is, that under conditions at which β-Gal was completely inactivated by proK, the activity of hen egg lysozyme, horseradish peroxidase, or Aspergillus sp. glucose oxidase remained unaltered.

  5. Computational Approach to Identify Enzymes That Are Potential Therapeutic Candidates for Psoriasis

    Directory of Open Access Journals (Sweden)

    Daeui Park

    2011-01-01

    Full Text Available Psoriasis is well known as a chronic inflammatory dermatosis. The disease affects persons of all ages and is a burden worldwide. Psoriasis is associated with various diseases such as arthritis. The disease is characterized by well-demarcated lesions on the skin of the elbows and knees. Various genetic and environmental factors are related to the pathogenesis of psoriasis. In order to identify enzymes that are potential therapeutic targets for psoriasis, we utilized a computational approach, combining microarray analysis and protein interaction prediction. We found 6,437 genes (3,264 upregulated and 3,173 downregulated that have significant differences in expression between regions with and without lesions in psoriasis patients. We identified potential candidates through protein-protein interaction predictions made using various protein interaction resources. By analyzing the hub protein of the networks with metrics such as degree and centrality, we detected 32 potential therapeutic candidates. After filtering these candidates through the ENZYME nomenclature database, we selected 5 enzymes: DNA helicase (RUVBL2, proteasome endopeptidase complex (PSMA2, nonspecific protein-tyrosine kinase (ZAP70, I-kappa-B kinase (IKBKE, and receptor protein-tyrosine kinase (EGFR. We adopted a computational approach to detect potential therapeutic targets; this approach may become an effective strategy for the discovery of new drug targets for psoriasis.

  6. Relationship between expression of matrix metalloproteinase-2 and matrix metalloproteinase-9 and invasion ability of cervical cancer cells.

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    Kato, Yasuhito; Yamashita, Tsuyoshi; Ishikawa, Mutsuo

    2002-01-01

    Constitutive overexpression of matrix metalloproteinases (MMPs) is frequently observed in malignant tumors. MMPs are a family of zinc endopeptidases consisting of at least 20 different members. In particular, MMP-2 and MMP-9 are reported to be closely associated with invasion and metastasis in several cancers. We investigated whether expression of MMP-2 and MMP-9 is associated with invasion ability of seven cervical cancer cells by administration of o-phenanthroline as MMP inhibitor. In two cell lines, Siha and Caski, MMP-2 mRNA and protein were expressed at high levels. After treatment with o-phenanthroline, the rate of invasion in these two cell lines was significantly decreased. In contrast, in the other two cell lines, HT-3 and Caski, high levels of MMP-9 mRNA and protein were expressed but there was no decrease in the rate of invasion in these cells after treatment with o-phenanthroline. The data suggest that expression level of MMP-2 mRNA may regulate with invasion ability of cervical cancer.

  7. Disruption of the cell wall lytic enzyme CwlO affects the amount and molecular size of poly-γ-glutamic acid produced by Bacillus subtilis (natto).

    Science.gov (United States)

    Mitsui, Nobuo; Murasawa, Hisashi; Sekiguchi, Junichi

    2011-01-01

    Poly-γ-glutamic acid (γPGA), a polymer of glutamic acid, is a component of the viscosity substance of natto, a traditional Japanese food made from soybeans fermented with Bacillus subtilis (natto). Here we investigate the effects of the cell wall lytic enzymes belonging to the D,L-endopeptidases (LytE, LytF, CwlO and CwlS) on γPGA production by B. subtilis (natto). γPGA levels in a cwlO disruptant were about twofold higher than that of the wild-type strain, whereas disruption of the lytE, lytF and cwlS genes had little effect on γPGA production. The molecular size of γPGA in the cwlO disruptant was larger than that of the wild-type strain. A complementary strain was constructed by insertion of the entire cwlO gene into the amyE locus of the CwlO mutant genome, and γPGA production was restored to wild-type levels in this complementary strain. These results indicated that the peptidoglycan degradation enzyme, CwlO, plays an important role in γPGA production and affects the molecular size of γPGA.

  8. Quantitative Förster resonance energy transfer analysis for kinetic determinations of SUMO-specific protease.

    Science.gov (United States)

    Liu, Yan; Song, Yang; Madahar, Vipul; Liao, Jiayu

    2012-03-01

    Förster resonance energy transfer (FRET) technology has been widely used in biological and biomedical research, and it is a very powerful tool for elucidating protein interactions in either dynamic or steady state. SUMOylation (the process of SUMO [small ubiquitin-like modifier] conjugation to substrates) is an important posttranslational protein modification with critical roles in multiple biological processes. Conjugating SUMO to substrates requires an enzymatic cascade. Sentrin/SUMO-specific proteases (SENPs) act as an endopeptidase to process the pre-SUMO or as an isopeptidase to deconjugate SUMO from its substrate. To fully understand the roles of SENPs in the SUMOylation cycle, it is critical to understand their kinetics. Here, we report a novel development of a quantitative FRET-based protease assay for SENP1 kinetic parameter determination. The assay is based on the quantitative analysis of the FRET signal from the total fluorescent signal at acceptor emission wavelength, which consists of three components: donor (CyPet-SUMO1) emission, acceptor (YPet) emission, and FRET signal during the digestion process. Subsequently, we developed novel theoretical and experimental procedures to determine the kinetic parameters, k(cat), K(M), and catalytic efficiency (k(cat)/K(M)) of catalytic domain SENP1 toward pre-SUMO1. Importantly, the general principles of this quantitative FRET-based protease kinetic determination can be applied to other proteases. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Evaluation of the therapeutic potential of a CNP analog in a Fgfr3 mouse model recapitulating achondroplasia.

    Science.gov (United States)

    Lorget, Florence; Kaci, Nabil; Peng, Jeff; Benoist-Lasselin, Catherine; Mugniery, Emilie; Oppeneer, Todd; Wendt, Dan J; Bell, Sean M; Bullens, Sherry; Bunting, Stuart; Tsuruda, Laurie S; O'Neill, Charles A; Di Rocco, Federico; Munnich, Arnold; Legeai-Mallet, Laurence

    2012-12-07

    Achondroplasia (ACH), the most common form of dwarfism, is an inherited autosomal-dominant chondrodysplasia caused by a gain-of-function mutation in fibroblast-growth-factor-receptor 3 (FGFR3). C-type natriuretic peptide (CNP) antagonizes FGFR3 downstream signaling by inhibiting the pathway of mitogen-activated protein kinase (MAPK). Here, we report the pharmacological activity of a 39 amino acid CNP analog (BMN 111) with an extended plasma half-life due to its resistance to neutral-endopeptidase (NEP) digestion. In ACH human growth-plate chondrocytes, we demonstrated a decrease in the phosphorylation of extracellular-signal-regulated kinases 1 and 2, confirming that this CNP analog inhibits fibroblast-growth-factor-mediated MAPK activation. Concomitantly, we analyzed the phenotype of Fgfr3(Y367C/+) mice and showed the presence of ACH-related clinical features in this mouse model. We found that in Fgfr3(Y367C/+) mice, treatment with this CNP analog led to a significant recovery of bone growth. We observed an increase in the axial and appendicular skeleton lengths, and improvements in dwarfism-related clinical features included flattening of the skull, reduced crossbite, straightening of the tibias and femurs, and correction of the growth-plate defect. Thus, our results provide the proof of concept that BMN 111, a NEP-resistant CNP analog, might benefit individuals with ACH and hypochondroplasia. Copyright © 2012 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  10. Desiccation tolerance of the resurrection plant Ramonda serbica is associated with dehydration-dependent changes in levels of proteolytic activities.

    Science.gov (United States)

    Kidrič, Marjetka; Sabotič, Jerica; Stevanović, Branka

    2014-07-15

    The unique response of desiccation-tolerant, or resurrection plants, to extreme drought is accompanied by major changes in the protein pool, raising the possibility of the involvement of proteases. We detected and characterized proteases present in their active state in leaf extracts of desiccated Ramonda serbica Panč., a resurrection plant from the Balkan Peninsula. Plants desiccated under laboratory conditions and maintained in anhydrobiosis for 4 and 14 months revived upon rehydration. Protease activities were determined spectrophotometrically in solution and by zymography on gels. Several endo- and aminopeptidases were detected and characterized by their pH profiles. Their enzyme class was determined using specific inhibitors. Those with higher activities were a serine endopeptidase active against Bz-Arg-pNA with a pH optimum around 9, and aminopeptidases optimally active at pHs from 7 to 9 against Leu-pNA, Met-pNA, Phe-pNA, Pro-pNA and Ala-pNA. The levels of their activities in leaf extracts from desiccated plants were significantly higher than those from rehydrated plants and from regularly watered plants, implying their involvement in the recovery of vegetative tissues from desiccation. Copyright © 2014 Elsevier GmbH. All rights reserved.

  11. 2-Deoxy glucose regulate MMP-9 in a SIRT-1 dependent and NFkB independent mechanism.

    Science.gov (United States)

    Edatt, Lincy; Haritha, K; Sruthi, T V; Aswini, P; Sameer Kumar, V B

    2016-12-01

    MMP9 is a member of the family of zinc-containing endopeptidases which degrade various components of the extracellular matrix, thereby regulating matrix remodeling. Since matrix remodeling plays an important role during growth and progression of cancer and considering the fact that, tumor cells switch to aerobic glycolysis as its major energy source, this study was designed to analyze if partial inhibition of glycolysis (the major energy pathway during hypoxia) can be used as a means to control matrix remodeling in terms of MMP9 activity and expression. For this, human epithelial carcinoma cells were treated with glycolytic inhibitor, 2-deoxy glucose (2DG) at sub-lethal concentrations followed by analysis of the expression and activity of MMP2 and MMP9. The experimental findings demonstrate that exposure of cancer cells to glycolytic inhibitor at concentration that does not induce ER stress, downregulates the activity and expression of MMP9 without affecting the expression levels and activity of MMP2. Further mechanistic analysis revealed that the regulation of MMP9 was mediated in a SIRT-1 dependent mechanism and did not alter the NFkB signaling pathway. The overall results presented here, therefore suggest that the use of glycolytic inhibitor, 2DG at concentration that do not affect cell viability or induce ER stress can be an effective strategy to control matrix remodeling.

  12. Sacubitril/valsartan in heart failure: latest evidence and place in therapy

    Science.gov (United States)

    Kaplinsky, Edgardo

    2016-01-01

    Despite significant therapeutic advances, patients with chronic heart failure (HF) remain at high risk for HF progression and death. Sacubitril/valsartan (previously known as LCZ696) is a first-in-class medicine that contains a neprilysin (NEP) inhibitor (sacubitril) and an angiotensin II (Ang-II) receptor blocker (valsartan). NEP is an endopeptidase that metabolizes different vasoactive peptides including natriuretic peptides, bradykinin and Ang-II. In consequence, its inhibition increases mainly the levels of both, natriuretic peptides (promoting diuresis, natriuresis and vasodilatation) and Ang-II whose effects are blocked by the angiotensin receptor blocker, valsartan (reducing vasoconstriction and aldosterone release). Results from the 8442 patient PARADIGM-HF study showed in patients with New York Heart Association (NYHA) class II–IV and reduced ejection fraction treated with LCZ696 (versus enalapril), the following benefits: reduction of the risk of death from cardiovascular causes by 20%; reduction of HF hospitalizations by 21%; reduction of the risk of all-cause mortality by 16%. Overall there was a 20% risk reduction on the primary endpoint, composite measure of cardiovascular (CV) death or time to first HF hospitalization. PARADIGM-HF was stopped early after a median follow up of 27 months. Post hoc analyses of PARADIGM-HF as well as the place in therapy of sacubitril/valsartan, including future directions, are included in the present review. PMID:27803793

  13. Changing the treatment of heart failure with reduced ejection fraction: clinical use of sacubitril-valsartan combination

    Science.gov (United States)

    Kaplinsky, Edgardo

    2016-01-01

    Despite significant therapeutic advances, patients with chronic heart failure (HF) remain at high risk of morbidity and mortality. Sacubitril valsartan (previously known as LCZ696) is a new oral agent approved for the treatment of symptomatic chronic heart failure in adults with reduced ejection fraction. It is described as the first in class angiotensin receptor neprilysin inhibitor (ARNI) since it incorporates the neprilysin inhibitor, sacubitril and the angiotensin II receptor antagonist, valsartan. Neprilysin is an endopeptidase that breaks down several vasoactive peptides including natriuretic peptides (NPs), bradykinin, endothelin and angiotensin II (Ang-II). Therefore, a natural consequence of its inhibition is an increase of plasmatic levels of both, NPs and Ang-II (with opposite biological actions). So, a combined inhibition of these both systems (Sacubitril / valsartan) may enhance the benefits of NPs effects in HF (natriuresis, diuresis, etc) while Ang-II receptor is inhibited (reducing vasoconstriction and aldosterone release). In a large clinical trial (PARADIGM-HF with 8442 patients), this new agent was found to significantly reduce cardiovascular and all cause mortality as well as hospitalizations due to HF (compared to enalapril). This manuscript reviews clinical evidence for sacubitril valsartan, dosing and cautions, future directions and its considered place in the therapy of HF with reduced ejection fraction. PMID:28133468

  14. Comparative proteomic analysis of early somatic and zygotic embryogenesis in Theobroma cacao L.

    Science.gov (United States)

    Noah, Alexandre Mboene; Niemenak, Nicolas; Sunderhaus, Stephanie; Haase, Christin; Omokolo, Denis Ndoumou; Winkelmann, Traud; Braun, Hans-Peter

    2013-01-14

    Somatic embryogenesis can efficiently foster the propagation of Theobroma cacao, but the poor quality of resulted plantlet hinders the use of this technique in the commercial scale. The current study has been initiated to systematically compare the physiological mechanisms underlying somatic and zygotic embryogenesis in T. cacao on the proteome level. About 1000 protein spots per fraction could be separated by two-dimensional isoelectric focusing/SDS PAGE. More than 50 of the protein spots clearly differed in abundance between zygotic and somatic embryos: 33 proteins spots were at least 3-fold higher in abundance in zygotic embryos and 20 in somatic embryos. Analyses of these protein spots differing in volume by mass spectrometry resulted in the identification of 68 distinct proteins. Many of the identified proteins are involved in genetic information processing (21 proteins), carbohydrate metabolism (11 proteins) and stress response (7 proteins). Somatic embryos especially displayed many stress related proteins, few enzymes involved in storage compound synthesis and an exceptional high abundance of endopeptidase inhibitors. Phosphoenolpyruvate carboxylase, which was accumulated more than 3-fold higher in zygotic embryos, represents a prominent enzyme in the storage compound metabolism in cacao seeds. Implications on the improvement of somatic embryogenesis in cacao are discussed. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Comparative proteomic analysis of extracellular matrix proteins secreted by hypertrophic scar with normal skin fibroblasts

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    Li Ma

    2014-04-01

    Full Text Available The formation of hypertrophic scars (HSs is a fibroproliferative disorder of abnormal wound healing. HSs usually characterize excessive proliferation of fibroblasts, abnormal deposition of extracellular matrix (ECM during wound healing, associated with cosmetic, functional, and psychological problems. Owing to the role of ECM proteins in scar formation, we comparatively analyzed matrix proteins secreted by normal skin fibroblasts (NSFs and HS fibroblasts (HSFs. The acetone-extracted secreted proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE, and identified by mass spectrometry (MS. Based on Go annotation of MS data, the profiling of ECM proteins was established and scar-related proteins have been screened out. The functions of several ECM proteins identified by MS have been discussed, such as collagens I, VI, XII, fibronectin, decorin, lumican, and protein procollagen C endopeptidase enhancer 1 (PCPE-1. Among them, the MS result of PCPE-1 was supported by Western blotting that PCPE-1 from HSFs were significantly upregulated than that from NSFs. It is suggested that PCPE-1 could be a potential target for scar treatment. The exploration of scar related proteins may provide new perspectives on understanding the mechanism of scar formation and open a new way to scar treatment and prevention.

  16. Accelerating sample preparation through enzyme-assisted microfiltration of Salmonella in chicken extract.

    Science.gov (United States)

    Vibbert, Hunter B; Ku, Seockmo; Li, Xuan; Liu, Xingya; Ximenes, Eduardo; Kreke, Thomas; Ladisch, Michael R; Deering, Amanda J; Gehring, Andrew G

    2015-01-01

    Microfiltration of chicken extracts has the potential to significantly decrease the time required to detect Salmonella, as long as the extract can be efficiently filtered and the pathogenic microorganisms kept in a viable state during this process. We present conditions that enable microfiltration by adding endopeptidase from Bacillus amyloliquefaciens to chicken extracts or chicken rinse, prior to microfiltration with fluid flow on both retentate and permeate sides of 0.2 μm cutoff polysulfone and polyethersulfone hollow fiber membranes. After treatment with this protease, the distribution of micron, submicron, and nanometer particles in chicken extracts changes so that the size of the remaining particles corresponds to 0.4-1 μm. Together with alteration of dissolved proteins, this change helps to explain how membrane fouling might be minimized because the potential foulants are significantly smaller or larger than the membrane pore size. At the same time, we found that the presence of protein protects Salmonella from protease action, thus maintaining cell viability. Concentration and recovery of 1-10 CFU Salmonella/mL from 400 mL chicken rinse is possible in less than 4 h, with the microfiltration step requiring less than 25 min at fluxes of 0.028-0.32 mL/cm(2) min. The entire procedure-from sample processing to detection by polymerase chain reaction-is completed in 8 h.

  17. Altered Peptidase Activities in Thyroid Neoplasia and Hyperplasia

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    Gorka Larrinaga

    2013-01-01

    Full Text Available Background. Papillary thyroid carcinoma (PTC, follicular thyroid adenoma (FTA, and thyroid nodular hyperplasia (TNH are the most frequent diseases of the thyroid gland. Previous studies described the involvement of dipeptidyl-peptidase IV (DPPIV/CD26 in the development of thyroid neoplasia and proposed it as an additional tool in the diagnosis/prognosis of these diseases. However, very little is known about the involvement of other peptidases in neoplastic and hyperplastic processes of this gland. Methods. The catalytic activity of 10 peptidases in a series of 30 PTC, 10 FTA, and 14 TNH was measured fluorimetrically in tumour and nontumour adjacent tissues. Results. The activity of DPPIV/CD26 was markedly higher in PTC than in FTA, TNH, and nontumour tissues. Aspartyl aminopeptidase (AspAP, alanyl aminopeptidase (AlaAP, prolyl endopeptidase, pyroglutamyl peptidase I, and aminopeptidase B activities were significantly increased in thyroid neoplasms when compared to nontumour tissues. AspAP and AlaAP activities were also significantly higher in PTC than in FTA and TNH. Conclusions. These data suggest the involvement of DPPIV/CD26 and some cytosolic peptidases in the neoplastic development of PTC and FTA. Further studies will help to define the possible clinical usefulness of AlaAP and AspAP in the diagnosis/prognosis of thyroid neoplasms.

  18. Deletion of PREPl causes growth impairment and hypotonia in mice.

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    Anna Mari Lone

    Full Text Available Genetic studies of rare diseases can identify genes of unknown function that strongly impact human physiology. Prolyl endopeptidase-like (PREPL is an uncharacterized member of the prolyl peptidase family that was discovered because of its deletion in humans with hypotonia-cystinuria syndrome (HCS. HCS is characterized by a number of physiological changes including diminished growth and neonatal hypotonia or low muscle tone. HCS patients have deletions in other genes as well, making it difficult to tease apart the specific role of PREPL. Here, we develop a PREPL null (PREPL(-/- mouse model to address the physiological role of this enzyme. Deletion of exon 11 from the Prepl gene, which encodes key catalytic amino acids, leads to a loss of PREPL protein as well as lower Prepl mRNA levels. PREPL(-/- mice have a pronounced growth phenotype, being significantly shorter and lighter than their wild type (PREPL(+/+ counterparts. A righting assay revealed that PREPL(-/- pups took significantly longer than PREPL(+/+ pups to right themselves when placed on their backs. This deficit indicates that PREPL(-/- mice suffer from neonatal hypotonia. According to these results, PREPL regulates growth and neonatal hypotonia in mice, which supports the idea that PREPL causes diminished growth and neonatal hypotonia in humans with HCS. These animals provide a valuable asset in deciphering the underlying biochemical, cellular and physiological pathways that link PREPL to HCS, and this may eventually lead to new insights in the treatment of this disease.

  19. Inhibition of matrix metalloproteinase-2 and 9 by Piroxicam confer neuroprotection in cerebral ischemia: an in silico evaluation of the hypothesis.

    Science.gov (United States)

    Mazumder, Muhammed Khairujjaman; Bhattacharya, Pallab; Borah, Anupom

    2014-12-01

    Matrix metalloproteinases are zinc-containing endopeptidases that are involved in extracellular matrix (ECM) remodeling cascade in many neurological disorders, including cerebral ischemia (CI). Remodeling of the ECM followed by disruption of the blood-brain barrier (BBB) is one of the major factors contributing to the ultimate neurodegeneration in CI. BBB disruption causes a cascade of pathophysiologies that trigger Anoikis-like cell death. While inhibition of MMP-2 and MMP-9 decreases the extent of neuronal damage in CI, MMP-2/9 knock-out mice have reduced infarct volume in experimental animal models of CI. Piroxicam, which is a non-steroidal anti-inflammatory drug (NSAID), has been demonstrated to be protective against aquaporin-4 and acid-sensing ion channel 1a--mediated neurodegeneration in CI. However, no report exists on the inhibitory action of Piroxicam on MMPs. We tested the hypothesis that Piroxicam, with its larger molecular size and more number of interacting pharmacophores, can inhibit MMP-2 and MMP-9. A comparative study on the inhibitory potential of Piroxicam with other reported MMP-inhibitors, viz., Aspirin, Melatonin and Doxycycline, has also been performed. Since the drug has already been reported to be neuroprotective through its inhibitory action in other pathways, it can be the drug of choice in the therapeutic management and prevention of neurodegeneration in CI.

  20. The enthesopathy of vitamin D-resistant osteomalacia in adults

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    C. Valvason

    2011-09-01

    Full Text Available A case of an adult patient with vitamin D-resistant osteomalacia or X-linked hypophosphatemic osteomalacia (XLH with diffuse calcification of entheses was reported. XLH is the most frequent cause of rickets in developed countries. It is characterized by an impaired renal transport of the phosphate and mutation of PFEX (phosphate regulating gene, with homologies to endopeptidase on the X-chromosome. In childhood, the classic clinical presentation includes short stature and bow leg. While at this age the main radiographic features are characterised by rickets, in adult life they are dominated by a generalised calcific enthesopathy. Concerning the pathogenesis of the enthesopathic lesions of XLH, no convincing hypothesis has yet been made. As in our patient, the extension and the severity of enthesopathy seems not related to the severity of the biochemical changes nor to the treatment with calcitriol. The calcified enthesopathy is an integral part of XLH and it is possible that it is found in adult because many years are necessary to produce it.

  1. Recommended Mass Spectrometry-Based Strategies to Identify Botulinum Neurotoxin-Containing Samples

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    Suzanne R. Kalb

    2015-05-01

    Full Text Available Botulinum neurotoxins (BoNTs cause the disease called botulism, which can be lethal. BoNTs are proteins secreted by some species of clostridia and are known to cause paralysis by interfering with nerve impulse transmission. Although the human lethal dose of BoNT is not accurately known, it is estimated to be between 0.1 μg to 70 μg, so it is important to enable detection of small amounts of these toxins. Our laboratory previously reported on the development of Endopep-MS, a mass-spectrometric‑based endopeptidase method to detect, differentiate, and quantify BoNT immunoaffinity purified from complex matrices. In this work, we describe the application of Endopep-MS for the analysis of thirteen blinded samples supplied as part of the EQuATox proficiency test. This method successfully identified the presence or absence of BoNT in all thirteen samples and was able to successfully differentiate the serotype of BoNT present in the samples, which included matrices such as buffer, milk, meat extract, and serum. Furthermore, the method yielded quantitative results which had z-scores in the range of −3 to +3 for quantification of BoNT/A containing samples. These results indicate that Endopep-MS is an excellent technique for detection, differentiation, and quantification of BoNT in complex matrices.

  2. Identification and initial characterization of matrix metalloproteinases in the yellow fever mosquito, Aedes aegypti.

    Science.gov (United States)

    Kantor, A M; Dong, S; Held, N L; Ishimwe, E; Passarelli, A L; Clem, R J; Franz, A W E

    2017-02-01

    Aedes aegypti is a major vector for arboviruses such as dengue, chikungunya and Zika viruses. During acquisition of a viremic bloodmeal, an arbovirus infects mosquito midgut cells before disseminating to secondary tissues, including the salivary glands. Once virus is released into the salivary ducts it can be transmitted to another vertebrate host. The midgut is surrounded by a basal lamina (BL) in the extracellular matrix, consisting of a proteinaceous mesh composed of collagen IV and laminin. BL pore size exclusion limit prevents virions from passing through. Thus, the BL probably requires remodelling via enzymatic activity to enable efficient virus dissemination. Matrix metalloproteinases (MMPs) are extracellular endopeptidases that are involved in remodelling of the extracellular matrix. Here, we describe and characterize the nine Ae. aegypti encoded MMPs, AeMMPs 1-9, which share common features with other invertebrate and vertebrate MMPs. Expression profiling in Ae. aegypti revealed that Aemmp4 and Aemmp6 were upregulated during metamorphosis, whereas expression of Aemmp1 and Aemmp2 increased during bloodmeal digestion. Aemmp1 expression was also upregulated in the presence of a bloodmeal containing chikungunya virus. Using polyclonal antibodies, AeMMP1 and AeMMP2 were specifically detected in tissues associated with the mosquito midgut. © 2016 The Royal Entomological Society.

  3. Alterations in plasma dipeptidyl peptidase IV enzyme activity in depression and schizophrenia: effects of antidepressants and antipsychotic drugs.

    Science.gov (United States)

    Maes, M; De Meester, I; Scharpe, S; Desnyder, R; Ranjan, R; Meltzer, H Y

    1996-01-01

    Recently, our laboratory reported that the activity of dipeptidyl-peptidase IV (DPP IV) was significantly lower in the peripheral blood of major depressed patients than in normal controls. The present study examines plasma DPP IV activity in 43 major depressed and 13 schizophrenic subjects versus 21 normal controls and the effects of antidepressants and antipsychotic drugs on plasma DPP IV activity. DPP IV activity was significantly lower in major depressed subjects than in normal controls and schizophrenic subjects. There was a trend towards higher DPP IV activity in schizophrenic patients than in normal controls. There were no significant effects of antidepressants or neuroleptics on plasma DPP IV activity in depressed and schizophrenic patients, respectively. There were no significant relationships between plasma DPP IV activity and plasma cortisol or immune-inflammatory markers, such as serum interleukin-6 (IL-6) or soluble IL-2 receptor. A significant and positive correlation was found between plasma DPP IV and prolyl endopeptidase (PEP) enzyme activity in the study group as a whole and in schizophrenic subjects. The results support the hypothesis that lower and higher plasma DPP IV activities are trait markers of major depression and schizophrenia, respectively. It is concluded that alterations in the enzyme activity of peptidases, such as DPP IV and PEP, play a role in the pathophysiology of major depression and schizophrenia.

  4. Evaluation of cathepsin B activity for degrading collagen IV using a surface plasmon resonance method and circular dichroism spectroscopy.

    Science.gov (United States)

    Shoji, Atsushi; Kabeya, Mitsutaka; Ishida, Yuuki; Yanagida, Akio; Shibusawa, Yoichi; Sugawara, Masao

    2014-07-01

    Evaluation of cathepsin B activities for degrading collagen IV and heat-denatured collagen IV (gelatin) were performed by surface plasmon resonance (SPR) and circular dichroism (CD) measurements. The optimal pH of cathepsin B activity for degrading each substrate was around 4.0. The ΔRU(15 min), which is a decrease in the SPR signal at 15 min after injection of cathepsin B, was smaller for collagen IV than for heat-denatured collagen IV owing to the presence of triple-helical conformation. An unstable nature of the triple-helical conformation of collagen IV at pH 4.0 was shown by the CD study. Degrading collagen IV by cathepsin B was facilitated owing to a local unwinding of the triple-helical conformation caused by proteolytic cleavage of the non-helical region. The concentration dependence of the initial velocity for degrading collagen IV by cathepsin B at pH 4.0 was biphasic, showing that cathepsin B at low concentration exhibits exopeptidase activity, while the enzyme at high concentration exhibits endopeptidase activity. The kinetic parameters for the exopeptidase activity of cathepsin B toward collagen IV and heat-treated collagen IV were evaluated and discussed in terms of the protease mechanism.

  5. Interaction and modulation of two antagonistic cell wall enzymes of mycobacteria.

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    Erik C Hett

    Full Text Available Bacterial cell growth and division require coordinated cell wall hydrolysis and synthesis, allowing for the removal and expansion of cell wall material. Without proper coordination, unchecked hydrolysis can result in cell lysis. How these opposing activities are simultaneously regulated is poorly understood. In Mycobacterium tuberculosis, the resuscitation-promoting factor B (RpfB, a lytic transglycosylase, interacts and synergizes with Rpf-interacting protein A (RipA, an endopeptidase, to hydrolyze peptidoglycan. However, it remains unclear what governs this synergy and how it is coordinated with cell wall synthesis. Here we identify the bifunctional peptidoglycan-synthesizing enzyme, penicillin binding protein 1 (PBP1, as a RipA-interacting protein. PBP1, like RipA, localizes both at the poles and septa of dividing cells. Depletion of the ponA1 gene, encoding PBP1 in M. smegmatis, results in a severe growth defect and abnormally shaped cells, indicating that PBP1 is necessary for viability and cell wall stability. Finally, PBP1 inhibits the synergistic hydrolysis of peptidoglycan by the RipA-RpfB complex in vitro. These data reveal a post-translational mechanism for regulating cell wall hydrolysis and synthesis through protein-protein interactions between enzymes with antagonistic functions.

  6. IgLON cell adhesion molecules are shed from the cell surface of cortical neurons to promote neuronal growth.

    Science.gov (United States)

    Sanz, Ricardo; Ferraro, Gino B; Fournier, Alyson E

    2015-02-13

    Matrix metalloproteinases and a disintegrin and metalloproteinases are members of the zinc endopeptidases, which cleave components of the extracellular matrix as well as cell surface proteins resulting in degradation or release of biologically active fragments. Surface ectodomain shedding affects numerous biological processes, including survival, axon outgrowth, axon guidance, and synaptogenesis. In this study, we evaluated the role of metalloproteinases in regulating cortical neurite growth. We found that treatment of mature cortical neurons with pan-metalloproteinase inhibitors or with tissue inhibitors of metalloproteinase-3 reduced neurite outgrowth. Through mass spectrometry, we characterized the metalloproteinase-sensitive cell surface proteome of mature cortical neurons. Members of the IgLON family of glycosylphosphatidylinositol-anchored neural cell adhesion molecules were identified and validated as proteins that were shed from the surface of mature cortical neurons in a metalloproteinase-dependent manner. Introduction of two members of the IgLON family, neurotrimin and NEGR1, in early embryonic neurons was sufficient to confer sensitivity to metalloproteinase inhibitors in neurite outgrowth assays. Outgrowth experiments on immobilized IgLON proteins revealed a role for all IgLON family members in promoting neurite extension from cortical neurons. Together, our findings support a role for metalloproteinase-dependent shedding of IgLON family members in regulating neurite outgrowth from mature cortical neurons.

  7. The matrix metalloproteinase in larynx cancer

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    Weronika Lucas Grzelczyk

    2016-12-01

    Full Text Available One of the most common carcinoma occurring in the head and neck is laryngeal cancer. Despite the rapid scientific advances in medicine the prognosis for patients with such type of disease is not satisfying. In the last few years matrix metalloproteinases ‑ MMPs and their tissue inhibitors – TIMPs, mostly MMP‑2 and MMP‑9, arouses a great interest, especially in the process of carcinogenesis. It seems that their impact in the formation and development of laryngeal cancer is significant. MMPs a group of zinc‑ and calcium‑ dependent endopeptidases play crucial role extracellular matrix collagen degradation. That are enzymes, that degrade and the basement membrane by facilitating tumor growth, cell migration and tumor invasion. They are implicated in metastasis and angiogenesis potentiate within the tumor. Clear tendency was observed towards the higher MMPs and TIMPs expression in larynx cancer than in the stroma. Recent studies show correlations between increased MMP‑2 gene expression in the tumor tissue and clinical status, histopathological grading and metastases occurrence. The similar MMP2 over expression dependence were found on tumor recurrence and survival. Many authors pointed out, significant higher MMP‑2 expression as a potential marker of tumor invasiveness and worse prognosis in patients with larynx cancer. However, association of MMP 9 gene expression with laryngeal cancer clinicopathological features and survival of patients are ambiguous. Although, numerous researches show that this relationship does exists. Similar correlations could be found in TIMPs, but further studies are necessary because of small amount of literature.

  8. Research Progress in Matrix Metalloproteinases in Intracranial Aneurysms%基质金属蛋白酶类在颅内动脉瘤中的研究进展

    Institute of Scientific and Technical Information of China (English)

    王楠斐(综述); 邹安琪(审校)

    2014-01-01

    基质金属蛋白酶(matrix metalloproteinase,MMPs)是一组同源的以无活性酶原形式分泌的依赖锌、钙离子为特点的内肽酶,它的重要作用是分解细胞外基质(extracellular matrix,ECM),在颅内动脉瘤的发生发展及破裂后的病理变化中发挥重要作用。本文对颅内动脉瘤发生发展过程及破裂后的病理变化中 MMPs 的表达与颅内动脉瘤(intracranial aneurysm,IA)之间的关系进行了综述。%Matrix metalloproteinases(MMPs)are a group of inactive Zn2+ and Ca2+-dependent endopeptidases responsible for the degradation of extracellular matrix components.MMPs play an important role in the occurrence,development and pathologic changes of intracranial aneurysms. This review summarizes the relationship between the expression of MMPs and intracranial aneu-rysms in the occurrence,development and pathologic changes of intracranial aneurysms.

  9. Molecular Mechanisms of Treadmill Therapy on Neuromuscular Atrophy Induced via Botulinum Toxin A

    Directory of Open Access Journals (Sweden)

    Sen-Wei Tsai

    2013-01-01

    Full Text Available Botulinum toxin A (BoNT-A is a bacterial zinc-dependent endopeptidase that acts specifically on neuromuscular junctions. BoNT-A blocks the release of acetylcholine, thereby decreasing the ability of a spastic muscle to generate forceful contraction, which results in a temporal local weakness and the atrophy of targeted muscles. BoNT-A-induced temporal muscle weakness has been used to manage skeletal muscle spasticity, such as poststroke spasticity, cerebral palsy, and cervical dystonia. However, the combined effect of treadmill exercise and BoNT-A treatment is not well understood. We previously demonstrated that for rats, following BoNT-A injection in the gastrocnemius muscle, treadmill running improved the recovery of the sciatic functional index (SFI, muscle contraction strength, and compound muscle action potential (CMAP amplitude and area. Treadmill training had no influence on gastrocnemius mass that received BoNT-A injection, but it improved the maximal contraction force of the gastrocnemius, and upregulation of GAP-43, IGF-1, Myo-D, Myf-5, myogenin, and acetylcholine receptor (AChR subunits α and β was found following treadmill training. Taken together, these results suggest that the upregulation of genes associated with neurite and AChR regeneration following treadmill training may contribute to enhanced gastrocnemius strength recovery following BoNT-A injection.

  10. Molecular Recognition of the Catalytic Zinc(II) Ion in MMP-13: Structure-Based Evolution of an Allosteric Inhibitor to Dual Binding Mode Inhibitors with Improved Lipophilic Ligand Efficiencies.

    Science.gov (United States)

    Fischer, Thomas; Riedl, Rainer

    2016-03-01

    Matrix metalloproteinases (MMPs) are a class of zinc dependent endopeptidases which play a crucial role in a multitude of severe diseases such as cancer and osteoarthritis. We employed MMP-13 as the target enzyme for the structure-based design and synthesis of inhibitors able to recognize the catalytic zinc ion in addition to an allosteric binding site in order to increase the affinity of the ligand. Guided by molecular modeling, we optimized an initial allosteric inhibitor by addition of linker fragments and weak zinc binders for recognition of the catalytic center. Furthermore we improved the lipophilic ligand efficiency (LLE) of the initial inhibitor by adding appropriate zinc binding fragments to lower the clogP values of the inhibitors, while maintaining their potency. All synthesized inhibitors showed elevated affinity compared to the initial hit, also most of the novel inhibitors displayed better LLE. Derivatives with carboxylic acids as the zinc binding fragments turned out to be the most potent inhibitors (compound 3 (ZHAWOC5077): IC50 = 134 nM) whereas acyl sulfonamides showed the best lipophilic ligand efficiencies (compound 18 (ZHAWOC5135): LLE = 2.91).

  11. Biological Mechanisms Underlying the Ultraviolet Radiation-Induced Formation of Skin Wrinkling and Sagging II: Over-Expression of Neprilysin Plays an Essential Role

    Directory of Open Access Journals (Sweden)

    Genji Imokawa

    2015-04-01

    Full Text Available Our previous studies strongly indicated that the up-regulated activity of skin fibroblast-derived elastase plays a pivotal role in wrinkling and/or sagging of the skin via the impairment of elastic fiber configuration and the subsequent loss of skin elasticity. Fortunately, we succeeded in identifying human skin fibroblast-derived elastase as a previously known enzyme, neprilysin or neutral endopeptidase (NEP. We have also characterized epithelial-mesenchymal paracrine cytokine interactions between UVB-exposed-keratinocytes and dermal fibroblasts and found that interleukin-1α and granulocyte macrophage colony stimulatory factor (GM-CSF are intrinsic cytokines secreted by UVB-exposed keratinocytes that stimulate the expression of neprilysin by fibroblasts. On the other hand, direct UVA exposure of human fibroblasts significantly stimulates the secretion of IL-6 and also elicits a significant increase in the gene expression of matrix metallo-protease(MMP-1 as well as neprilysin (to a lesser extent, which is followed by distinct increases in their protein and enzymatic activity levels. Direct UVA exposure of human keratinocytes also stimulates the secretion of IL-6, IL-8 and GM-CSF but not of IL-1 and endothelin-1. These findings suggest that GM-CSF secreted by UVA-exposed keratinocytes as well as IL-6 secreted by UVA-exposed dermal fibroblasts play important and additional roles in UVA-induced sagging and wrinkling by up-regulation of neprilysin and MMP-1, respectively, in dermal fibroblasts.

  12. Biological mechanisms underlying the ultraviolet radiation-induced formation of skin wrinkling and sagging II: over-expression of neprilysin plays an essential role.

    Science.gov (United States)

    Imokawa, Genji; Nakajima, Hiroaki; Ishida, Koichi

    2015-04-08

    Our previous studies strongly indicated that the up-regulated activity of skin fibroblast-derived elastase plays a pivotal role in wrinkling and/or sagging of the skin via the impairment of elastic fiber configuration and the subsequent loss of skin elasticity. Fortunately, we succeeded in identifying human skin fibroblast-derived elastase as a previously known enzyme, neprilysin or neutral endopeptidase (NEP). We have also characterized epithelial-mesenchymal paracrine cytokine interactions between UVB-exposed-keratinocytes and dermal fibroblasts and found that interleukin-1α and granulocyte macrophage colony stimulatory factor (GM-CSF) are intrinsic cytokines secreted by UVB-exposed keratinocytes that stimulate the expression of neprilysin by fibroblasts. On the other hand, direct UVA exposure of human fibroblasts significantly stimulates the secretion of IL-6 and also elicits a significant increase in the gene expression of matrix metallo-protease(MMP)-1 as well as neprilysin (to a lesser extent), which is followed by distinct increases in their protein and enzymatic activity levels. Direct UVA exposure of human keratinocytes also stimulates the secretion of IL-6, IL-8 and GM-CSF but not of IL-1 and endothelin-1. These findings suggest that GM-CSF secreted by UVA-exposed keratinocytes as well as IL-6 secreted by UVA-exposed dermal fibroblasts play important and additional roles in UVA-induced sagging and wrinkling by up-regulation of neprilysin and MMP-1, respectively, in dermal fibroblasts.

  13. IgLON Cell Adhesion Molecules Are Shed from the Cell Surface of Cortical Neurons to Promote Neuronal Growth*

    Science.gov (United States)

    Sanz, Ricardo; Ferraro, Gino B.; Fournier, Alyson E.

    2015-01-01

    Matrix metalloproteinases and a disintegrin and metalloproteinases are members of the zinc endopeptidases, which cleave components of the extracellular matrix as well as cell surface proteins resulting in degradation or release of biologically active fragments. Surface ectodomain shedding affects numerous biological processes, including survival, axon outgrowth, axon guidance, and synaptogenesis. In this study, we evaluated the role of metalloproteinases in regulating cortical neurite growth. We found that treatment of mature cortical neurons with pan-metalloproteinase inhibitors or with tissue inhibitors of metalloproteinase-3 reduced neurite outgrowth. Through mass spectrometry, we characterized the metalloproteinase-sensitive cell surface proteome of mature cortical neurons. Members of the IgLON family of glycosylphosphatidylinositol-anchored neural cell adhesion molecules were identified and validated as proteins that were shed from the surface of mature cortical neurons in a metalloproteinase-dependent manner. Introduction of two members of the IgLON family, neurotrimin and NEGR1, in early embryonic neurons was sufficient to confer sensitivity to metalloproteinase inhibitors in neurite outgrowth assays. Outgrowth experiments on immobilized IgLON proteins revealed a role for all IgLON family members in promoting neurite extension from cortical neurons. Together, our findings support a role for metalloproteinase-dependent shedding of IgLON family members in regulating neurite outgrowth from mature cortical neurons. PMID:25538237

  14. Cobalt (III) complexes as novel matrix metalloproteinase-9 inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jiyoun [Sungshin Women' s Univ., Seoul (Korea, Republic of)

    2012-04-15

    We have synthesized a series of novel MMP-9 inhibitors containing cobalt(III) complexes. The synthesized cobalt(III) complexes are effective as enzyme inhibitors and the attachment of a biphenyl group enhanced the efficiency of enzyme inhibition up to 6-fold. When compared to the reported non-hydroxamate MMP inhibitors, the synthesized complexes showed comparable in vitro potency. The enzyme assay showed that the cobalt(III) complex can disrupt the zinc binding active site of MMP-9 and is proposed to work via a ligand exchange mechanism. Since histidine residues are essential for the catalytic activity of a large percentage of enzymes and zinc finger proteins, these cobalt(III) complexes can serve as a prototype inhibitor towards various zinc containing enzymes and proteins. Matrix metalloproteinases (MMPs) are a family of zinc binding endopeptidases that play crucial roles in various physiological processes and diseases such as embryogenic growth, angiogenesis, arthritis, skin ulceration, liver fibrosis and tumor metastasis. Because of their implications in a wide range of diseases, MMPs are considered as intriguing drug targets. The majority of MMP inhibitors are organic small molecules containing a hydroxamate functionality for the zinc binding group. This hydroxamate group binds to a zinc(II) center in a bidentate fashion and creates a distorted trigonal bipyramidal geometry.

  15. A Potential Role for Acrolein in Neutrophil-Mediated Chronic Inflammation.

    Science.gov (United States)

    Noerager, Brett D; Xu, Xin; Davis, Virginia A; Jones, Caleb W; Okafor, Svetlana; Whitehead, Alicia; Blalock, J Edwin; Jackson, Patricia L

    2015-12-01

    Neutrophils (PMNs) are key mediators of inflammatory processes throughout the body. In this study, we investigated the role of acrolein, a highly reactive aldehyde that is ubiquitously present in the environment and produced endogenously at sites of inflammation, in mediating PMN-mediated degradation of collagen facilitating proline-glycine-proline (PGP) production. We treated peripheral blood neutrophils with acrolein and analyzed cell supernatants and lysates for matrix metalloproteinase-9 (MMP-9) and prolyl endopeptidase (PE), assessed their ability to break down collagen and release PGP, and assayed for the presence of leukotriene A4 hydrolase (LTA4H) and its ability to degrade PGP. Acrolein treatment induced elevated production and functionality of collagen-degrading enzymes and generation of PGP fragments. Meanwhile, LTA4H levels and triaminopeptidase activity declined with increasing concentrations of acrolein thereby sparing PGP from enzymatic destruction. These findings suggest that acrolein exacerbates the acute inflammatory response mediated by neutrophils and sets the stage for chronic pulmonary and systemic inflammation.

  16. Papain-like peptidases: structure, function, and evolution.

    Science.gov (United States)

    Novinec, Marko; Lenarčič, Brigita

    2013-06-01

    Papain-like cysteine peptidases are a diverse family of peptidases found in most known organisms. In eukaryotes, they are divided into multiple evolutionary groups, which can be clearly distinguished on the basis of the structural characteristics of the proenzymes. Most of them are endopeptidases; some, however, evolved into exopeptidases by obtaining additional structural elements that restrict the binding of substrate into the active site. In humans, papain-like peptidases, also called cysteine cathepsins, act both as non-specific hydrolases and as specific processing enzymes. They are involved in numerous physiological processes, such as antigen presentation, extracellular matrix remodeling, and hormone processing. Their activity is tightly regulated and dysregulation of one or more cysteine cathepsins can result in severe pathological conditions, such as cardiovascular diseases and cancer. Other organisms can utilize papain-like peptidases for different purposes and they are often part of host-pathogen interactions. Numerous parasites, such as Plasmodium and flukes, utilize papain-like peptidases for host invasion, whereas plants, in contrast, use these enzymes for host defense. This review presents a state-of-the-art description of the structure and phylogeny of papain-like peptidases as well as an overview of their physiological and pathological functions in humans and in other organisms.

  17. Evolution of peptidoglycan biosynthesis under the selective pressure of antibiotics in Gram-positive bacteria.

    Science.gov (United States)

    Mainardi, Jean-Luc; Villet, Régis; Bugg, Timothy D; Mayer, Claudine; Arthur, Michel

    2008-03-01

    Acquisition of resistance to the two classes of antibiotics therapeutically used against Gram-positive bacteria, the glycopeptides and the beta-lactams, has revealed an unexpected flexibility in the peptidoglycan assembly pathway. Glycopeptides select for diversification of the fifth position of stem pentapeptides because replacement of D-Ala by D-lactate or D-Ser at this position prevents binding of the drugs to peptidoglycan precursors. The substitution is generally well tolerated by the classical D,D-transpeptidases belonging to the penicillin-binding protein family, except by low-affinity enzymes. Total elimination of the fifth residue by a D,D-carboxypeptidase requires a novel cross-linking enzyme able to process the resulting tetrapeptide stems. This enzyme, an L,D-transpeptidase, confers cross-resistance to beta-lactams and glycopeptides. Diversification of the side chain of the precursors, presumably in response to the selective pressure of peptidoglycan endopeptidases, is controlled by aminoacyl transferases of the Fem family that redirect specific aminoacyl-tRNAs from translation to peptidoglycan synthesis. Diversification of the side chains has been accompanied by a parallel divergent evolution of the substrate specificity of the L,D-transpeptidases, in contrast to the D,D-transpeptidases, which display an unexpected broad specificity. This review focuses on the role of antibiotics in selecting or counter-selecting diversification of the structure of peptidoglycan precursors and their mode of polymerization.

  18. Activity of soluble aminopeptidase A and dipeptidyl peptidase IV and membrane-bound aminopeptidase B and pyroglutamyl peptidase I in adenoid hyperplasia, tonsillar hyperplasia and chronic tonsillitis.

    Science.gov (United States)

    Larrinaga, Gorka; Perez, Itxaro; Sanz, Begoña; Irazusta, Amaya; Zarrazquin, Idoia; Sanchez, Clara Elena; Sanchez, Carmen Elena; Rey, Ana Sanchez Del; Zabala, Aitor; Santaolalla, Francisco

    2011-11-01

    To analyze soluble and membrane-bound peptidase activities in the tonsils and adenoids removed from patients with adenoid hyperplasia, tonsillar hyperplasia and chronic tonsillitis. A total of 48 tissue samples from patients undergoing adenoidectomy and tonsillectomy for adenoid hyperplasia, tonsillar hyperplasia or chronic tonsillitis were analyzed. The catalytic activity of a pool of peptidases in the soluble (dipeptidyl peptidase IV, aminopeptidase A, aminopeptidase N and cystinyl aminopeptidase) and membrane-bound (prolyl endopeptidase, aspartyl aminopeptidase, aminopeptidase B and pyroglutamyl peptidase I) fractions was measured fluorometrically. The activity of membrane-bound aminopeptidase B was higher in cases of chronic tonsillitis and adenoid hyperplasia than in tonsillar hyperplasia, p=0.004. Soluble dipeptidyl peptidase IV and membrane-bound pyroglutamyl peptidase I were found to be more active in tissues from male chronic tonsillitis tissues, pchronic tonsillitis, soluble aminopeptidase A was found to have a higher level of activity in tissues from children than those from adults, p=0.005. Our results suggest a potential role of soluble aminopeptidase A, soluble dipeptidyl peptidase IV, membrane-bound aminopeptidase B and membrane-bound pyroglutamyl peptidase I in the pathobiology of adenoid hyperplasia, tonsillar hyperplasia and chronic tonsillitis that is differently regulated as a function of gender. These finfings may modify in the future the clinical approach to these diseases. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  19. Alignment-free ultra-high-throughput comparison of druggable protein-ligand binding sites.

    Science.gov (United States)

    Weill, Nathanaël; Rognan, Didier

    2010-01-01

    Inferring the biological function of a protein from its three-dimensional structure as well as explaining why a drug may bind to various targets is of crucial importance to modern drug discovery. Here we present a generic 4833-integer vector describing druggable protein-ligand binding sites that can be applied to any protein and any binding cavity. The fingerprint registers counts of pharmacophoric triplets from the Calpha atomic coordinates of binding-site-lining residues. Starting from a customized data set of diverse protein-ligand binding site pairs, the most appropriate metric and a similarity threshold could be defined for similar binding sites. The method (FuzCav) has been used in various scenarios: (i) screening a collection of 6000 binding sites for similarity to different queries; (ii) classifying protein families (serine endopeptidases, protein kinases) by binding site diversity; (iii) discriminating adenine-binding cavities from decoys. The fingerprint generation and comparison supports ultra-high throughput (ca. 1000 measures/s), does not require prior alignment of protein binding sites, and is able to detect local similarity among subpockets. It is thus particularly well suited to the functional annotation of novel genomic structures with low sequence identity to known X-ray templates.

  20. Inhibition of matrix metalloproteinase-2 by PARP inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Nicolescu, Adrian C.; Holt, Andrew; Kandasamy, Arulmozhi D. [Departments of Pharmacology and Pediatrics, Cardiovascular Research Centre, University of Alberta, Edmonton, Alta., Canada T6G 2S2 (Canada); Pacher, Pal [National Institutes of Health, NIAAA, Laboratory of Physiologic Studies, Bethesda, MD (United States); Schulz, Richard, E-mail: richard.schulz@ualberta.ca [Departments of Pharmacology and Pediatrics, Cardiovascular Research Centre, University of Alberta, Edmonton, Alta., Canada T6G 2S2 (Canada)

    2009-10-02

    Matrix metalloproteinase-2 (MMP-2), a ubiquitously expressed zinc-dependent endopeptidase, and poly(ADP-ribosyl) polymerase (PARP), a nuclear enzyme regulating DNA repair, are activated by nitroxidative stress associated with various pathologies. As MMP-2 plays a detrimental role in heart injuries resulting from enhanced nitroxidative stress, where PARP and MMP inhibitors are beneficial, we hypothesized that PARP inhibitors may affect MMP-2 activity. Using substrate degradation assays to determine MMP-2 activity we found that four PARP inhibitors (3-AB, PJ-34, 5-AIQ, and EB-47) inhibited 64 kDa MMP-2 in a concentration-dependent manner. The IC{sub 50} values of PJ-34 and 5-AIQ were in the high micromolar range and comparable to those of known MMP-2 inhibitors doxycycline, minocycline or o-phenanthroline, whereas those for 3-AB and EB-47 were in the millimolar range. Co-incubation of PARP inhibitors with doxycycline showed an additive inhibition of MMP-2 that was significant for 3-AB alone. These data demonstrate that the protective effects of some PARP inhibitors may include inhibition of MMP-2 activity.