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[PMID]: 28476889 [Au] Autor: Singh R; Jamdar SN; Goyal VD; Kumar A; Ghosh B; Makde RD [Ad] Endereço: From the High Pressure and Synchrotron Radiation Physics Division and. [Ti] Título: Structure of the human aminopeptidase XPNPEP3 and comparison of its activity with Icp55 orthologs: Insights into diverse cellular processes. [So] Source: J Biol Chem;292(24):10035-10047, 2017 Jun 16. [Is] ISSN: 1083-351X [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: The human aminopeptidase XPNPEP3 is associated with cystic kidney disease and TNF-TNFR2 cellular signaling. Its yeast and plant homolog Icp55 processes several imported mitochondrial matrix proteins leading to their stabilization. However, the molecular basis for the diverse roles of these enzymes in the cell is unknown. Here, we report the crystal structure of human XPNPEP3 with bound apstatin product at 1.65 Å resolution, and we compare its substrate specificity with those of fungal Icp55 enzymes. In contrast to the suggestions by earlier studies of mitochondrial processing, we found that these enzymes are genuine Xaa-Pro aminopeptidases, which hydrolyze peptides with proline at the second position (P1'). The mitochondrial processing activity involving cleavage of peptides lacking P1' proline was also detected in the purified enzymes. A wide proline pocket as well as molecular complementarity and capping at the S1 substrate site of XPNPEP3 provide the necessary structural features for processing the mitochondrial substrates. However, this activity was found to be significantly lower as compared with Xaa-Pro aminopeptidase activity. Because of similar activity profiles of Icp55 and XPNPEP3, we propose that XPNPEP3 plays the same mitochondrial role in humans as Icp55 does in yeast. Both Xaa-Pro aminopeptidase and mitochondrial processing activities of XPNPEP3 have implications toward mitochondrial fitness and cystic kidney disease. Furthermore, the presence of both these activities in Icp55 elucidates the unexplained processing of the mitochondrial cysteine desulfurase Nfs1 in yeast. The enzymatic and structural analyses reported here provide a valuable molecular framework for understanding the diverse cellular roles of XPNPEP3. [Mh] Termos MeSH primário: Aminopeptidases/metabolismo Eremothecium/enzimologia Proteínas Fúngicas/metabolismo Fusarium/enzimologia Metaloexopeptidases/metabolismo Mitocôndrias/enzimologia Modelos Moleculares [Mh] Termos MeSH secundário: Aminopeptidases/química Aminopeptidases/genética Proteínas de Arabidopsis/química Proteínas de Arabidopsis/genética Proteínas de Arabidopsis/metabolismo Domínio Catalítico Cristalografia por Raios X Bases de Dados de Proteínas Proteínas Fúngicas/química Proteínas Fúngicas/genética Seres Humanos Metaloexopeptidases/química Metaloexopeptidases/genética Metaloproteases/química Metaloproteases/genética Metaloproteases/metabolismo Mitocôndrias/metabolismo Proteínas Mitocondriais/química Proteínas Mitocondriais/metabolismo Mutação Fragmentos de Peptídeos/química Fragmentos de Peptídeos/metabolismo Peptídeos/química Peptídeos/metabolismo Conformação Proteica Proteínas Recombinantes/química Proteínas Recombinantes/metabolismo Proteínas de Saccharomyces cerevisiae/química Proteínas de Saccharomyces cerevisiae/genética Proteínas de Saccharomyces cerevisiae/metabolismo Homologia Estrutural de Proteína Especificidade por Substrato Sulfurtransferases/química Sulfurtransferases/metabolismo [Pt] Tipo de publicação: COMPARATIVE STUDY; JOURNAL ARTICLE [Nm] Nome de substância: 0 (Arabidopsis Proteins); 0 (Fungal Proteins); 0 (Mitochondrial Proteins); 0 (Peptide Fragments); 0 (Peptides); 0 (Recombinant Proteins); 0 (Saccharomyces cerevisiae Proteins); 0 (apstatin); EC 2.8.1.- (Sulfurtransferases); EC 2.8.1.7 (NFS1 protein, S cerevisiae); EC 3.4.- (ICP55 protein, Arabidopsis); EC 3.4.- (Icp55 protein, S cerevisiae); EC 3.4.- (Metalloexopeptidases); EC 3.4.- (Metalloproteases); EC 3.4.11.- (Aminopeptidases); EC 3.4.11.- (aminopeptidase P3, human); EC 3.4.11.9 (X-Pro aminopeptidase) [Em] Mês de entrada: 1707 [Cu] Atualização por classe: 170706 [Lr] Data última revisão: 170706 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170507 [St] Status: MEDLINE [do] DOI: 10.1074/jbc.M117.783357

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[PMID]: 27006448 [Au] Autor: Kim YH; Barclay JL; He J; Luo X; O'Neill HM; Keshvari S; Webster JA; Ng C; Hutley LJ; Prins JB; Whitehead JP [Ad] Endereço: Metabolic Medicine Group, Mater Research Institute, University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia. [Ti] Título: Identification of carboxypeptidase X (CPX)-1 as a positive regulator of adipogenesis. [So] Source: FASEB J;30(7):2528-40, 2016 07. [Is] ISSN: 1530-6860 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Adipose tissue expansion occurs through a combination of hypertrophy of existing adipocytes and generation of new adipocytes via the process of hyperplasia, which involves the proliferation and subsequent differentiation of preadipocytes. Deficiencies in hyperplasia contribute to adipose tissue dysfunction and the association of obesity with chronic cardiometabolic diseases. Thus, increased understanding of hyperplastic pathways may be expected to afford novel therapeutic strategies. We have reported that fibroblast growth factor (FGF)-1 promotes proliferation and differentiation of human preadipocytes and recently demonstrated that bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI) is a central, proximal effector. Herein, we describe the identification and characterization of carboxypeptidase X (CPX)-1, a secreted collagen-binding glycoprotein, as a novel downstream effector in human primary and Simpson-Golabi-Behmel syndrome preadipocytes. CPX-1 expression increased after treatment of preadipocytes with FGF-1, BAMBI knockdown, or induction of differentiation. CPX-1 knockdown compromised preadipocyte differentiation coincident with reduced collagen expression. Furthermore, preadipocytes differentiated on matrix derived from CPX-1 knockdown cells exhibited reduced Glut4 expression and insulin-stimulated glucose uptake. Finally, CPX-1 expression was increased in adipose tissue from obese mice and humans. Collectively, these findings establish CPX-1 as a positive regulator of adipogenesis situated downstream of FGF-1/BAMBI that may contribute to hyperplastic adipose tissue expansion via affecting extracellular matrix remodeling.-Kim, Y.-H., Barclay, J. L., He, J., Luo, X., O'Neill, H. M., Keshvari, S., Webster, J. A., Ng, C., Hutley, L. J., Prins, J. B., Whitehead, J. P. Identification of carboxypeptidase X (CPX)-1 as a positive regulator of adipogenesis. [Mh] Termos MeSH primário: Adipogenia/fisiologia Tecido Adiposo/metabolismo Regulação da Expressão Gênica/fisiologia Glicoproteínas/metabolismo Metaloexopeptidases/metabolismo [Mh] Termos MeSH secundário: Adipócitos/metabolismo Adipócitos/fisiologia Adipogenia/efeitos dos fármacos Adulto Animais Diferenciação Celular Gorduras na Dieta/administração & dosagem Gorduras na Dieta/efeitos adversos Feminino Fator 1 de Crescimento de Fibroblastos/genética Fator 1 de Crescimento de Fibroblastos/metabolismo Regulação da Expressão Gênica/efeitos dos fármacos Técnicas de Silenciamento de Genes Glicoproteínas/genética Seres Humanos Masculino Proteínas de Membrana/genética Proteínas de Membrana/metabolismo Metaloexopeptidases/genética Camundongos Meia-Idade Obesidade/etiologia Obesidade/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T [Nm] Nome de substância: 0 (BAMBI protein, human); 0 (Bambi protein, mouse); 0 (CPX-1 protein, human); 0 (Dietary Fats); 0 (Glycoproteins); 0 (Membrane Proteins); 104781-85-3 (Fibroblast Growth Factor 1); EC 3.4.- (Metalloexopeptidases); EC 3.4.17.- (Cpxm1 protein, mouse) [Em] Mês de entrada: 1708 [Cu] Atualização por classe: 171124 [Lr] Data última revisão: 171124 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 160324 [St] Status: MEDLINE [do] DOI: 10.1096/fj.201500107R

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[PMID]: 26603934 [Au] Autor: Kim YH; O'Neill HM; Whitehead JP [Ad] Endereço: Mater Research Institute-University of Queensland, Translational Research Institute, Brisbane, Queensland, Australia. [Ti] Título: Carboxypeptidase X-1 (CPX-1) is a secreted collagen-binding glycoprotein. [So] Source: Biochem Biophys Res Commun;468(4):894-9, 2015 Dec 25. [Is] ISSN: 1090-2104 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Carboxypeptidase X-1 (CPX-1) is an atypical member of the carboxypeptidase (CP) family of proteins involved in a variety of physiological and pathological processes. However, unlike most other family members CPX-1 lacks catalytic activity making its biological function unclear. CPX-1 contains a 160 amino acid discoidin domain (DSD) that serves as a binding domain in other proteins prompting us to investigate a putative functional role for this domain in CPX-1. Sequence alignment confirmed the overarching homology between the DSD of CPX-1 and other DSDs whilst more detailed analysis revealed conservation of the residues known to form the collagen-binding trench within the DSD of the discoidin domain receptors (DDRs) 1 and 2. Biochemical characterisation of transiently expressed human CPX-1 revealed that CPX-1 was secreted in an N-glycosylation-dependent manner as treatment with the N-glycosylation inhibitor tunicamycin inhibited secretion concomitant with a reduction in CPX-1 mobility on Western blot. Using a collagen pull-down assay we found that secreted CPX-1 bound collagen and this appeared independent of N-glycosylation as treatment with PNGaseF did not affect binding. Further analysis under non-reducing and reducing (+DTT) conditions revealed that CPX-1 was secreted in both monomeric and dimeric forms and only the former bound collagen. Finally, mutation of a key residue situated within the putative collagen-binding trench within the DSD of CPX-1 (R192A) significantly reduced secretion and collagen-binding by 40% and 60%, respectively. Collectively these results demonstrate that CPX-1 is a secreted collagen-binding glycoprotein and provide a foundation for future studies investigating the function of CPX-1. [Mh] Termos MeSH primário: Colágeno/química Colágeno/metabolismo Glicoproteínas/química Glicoproteínas/metabolismo Metaloexopeptidases/química Metaloexopeptidases/metabolismo [Mh] Termos MeSH secundário: Animais Células CHO Cricetulus Ativação Enzimática Glicosilação Células HEK293 Seres Humanos Ligação Proteica Estrutura Terciária de Proteína Especificidade por Substrato [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T [Nm] Nome de substância: 0 (Glycoproteins); 9007-34-5 (Collagen); EC 3.4.- (Metalloexopeptidases); EC 3.4.17.- (Cpxm1 protein, mouse) [Em] Mês de entrada: 1604 [Cu] Atualização por classe: 151223 [Lr] Data última revisão: 151223 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 151126 [St] Status: MEDLINE

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[PMID]: 25232897 [Au] Autor: Zhang L; Franks J; Stolz DB; Conway JF; Thibodeau PH [Ad] Endereço: Departments of Cell Biology and ‡Structural Biology, The University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania 15261, United States. [Ti] Título: Inducible polymerization and two-dimensional assembly of the repeats-in-toxin (RTX) domain from the Pseudomonas aeruginosa alkaline protease. [So] Source: Biochemistry;53(41):6452-62, 2014 Oct 21. [Is] ISSN: 1520-4995 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Self-assembling proteins represent potential scaffolds for the organization of enzymatic activities. The alkaline protease repeats-in-toxin (RTX) domain from Pseudomonas aeruginosa undergoes multiple structural transitions in the presence and absence of calcium, a native structural cofactor. In the absence of calcium, this domain is capable of spontaneous, ordered polymerization, producing amyloid-like fibrils and large two-dimensional protein sheets. This polymerization occurs under near-physiological conditions, is rapid, and can be controlled by regulating calcium in solution. Fusion of the RTX domain to a soluble protein results in the incorporation of engineered protein function into these macromolecular assemblies. Applications of this protein sequence in bacterial adherence and colonization and the generation of biomaterials are discussed. [Mh] Termos MeSH primário: Amiloide/química Proteínas de Bactérias/química Cálcio/química Metaloexopeptidases/química Modelos Moleculares Pseudomonas aeruginosa/enzimologia [Mh] Termos MeSH secundário: Fosfatase Alcalina/química Fosfatase Alcalina/genética Fosfatase Alcalina/metabolismo Fosfatase Alcalina/ultraestrutura Amiloide/genética Amiloide/metabolismo Amiloide/ultraestrutura Proteínas de Bactérias/genética Proteínas de Bactérias/metabolismo Proteínas de Bactérias/ultraestrutura Cálcio/metabolismo Dicroísmo Circular Proteínas de Fluorescência Verde/química Proteínas de Fluorescência Verde/genética Proteínas de Fluorescência Verde/metabolismo Proteínas de Fluorescência Verde/ultraestrutura Cinética Metaloexopeptidases/genética Metaloexopeptidases/metabolismo Metaloexopeptidases/ultraestrutura Microscopia Eletrônica de Varredura Microscopia Eletrônica de Transmissão Polimerização Agregação Patológica de Proteínas Engenharia de Proteínas Dobramento de Proteína Domínios e Motivos de Interação entre Proteínas Proteínas Recombinantes de Fusão/química Proteínas Recombinantes de Fusão/metabolismo Proteínas Recombinantes de Fusão/ultraestrutura Sequências Repetitivas de Aminoácidos Serina Endopeptidases/química Serina Endopeptidases/genética Serina Endopeptidases/metabolismo Serina Endopeptidases/ultraestrutura [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL [Nm] Nome de substância: 0 (Amyloid); 0 (Bacterial Proteins); 0 (Recombinant Fusion Proteins); 147336-22-9 (Green Fluorescent Proteins); EC 3.1.3.1 (Alkaline Phosphatase); EC 3.1.3.1 (AprP protease, Pseudomonas); EC 3.4.- (Metalloexopeptidases); EC 3.4.21.- (Pseudomonas serine proteinase); EC 3.4.21.- (Serine Endopeptidases); SY7Q814VUP (Calcium) [Em] Mês de entrada: 1412 [Cu] Atualização por classe: 170220 [Lr] Data última revisão: 170220 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 140919 [St] Status: MEDLINE [do] DOI: 10.1021/bi5007546

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[PMID]: 23539623 [Au] Autor: Mendel RR [Ad] Endereço: Department of Plant Biology, Braunschweig University of Technology, 38106 Braunschweig, Germany. r.mendel@tu-bs.de [Ti] Título: The molybdenum cofactor. [So] Source: J Biol Chem;288(19):13165-72, 2013 May 10. [Is] ISSN: 1083-351X [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: The transition element molybdenum needs to be complexed by a special cofactor to gain catalytic activity. Molybdenum is bound to a unique pterin, thus forming the molybdenum cofactor (Moco), which, in different variants, is the active compound at the catalytic site of all molybdenum-containing enzymes in nature, except bacterial molybdenum nitrogenase. The biosynthesis of Moco involves the complex interaction of six proteins and is a process of four steps, which also require iron, ATP, and copper. After its synthesis, Moco is distributed, involving Moco-binding proteins. A deficiency in the biosynthesis of Moco has lethal consequences for the respective organisms. [Mh] Termos MeSH primário: Coenzimas/biossíntese Metaloproteínas/biossíntese Molibdênio/metabolismo [Mh] Termos MeSH secundário: Animais Vias Biossintéticas Coenzimas/química Seres Humanos Metaloexopeptidases Metaloproteínas/química Metaloproteínas/metabolismo Molibdênio/química Compostos Organofosforados/metabolismo Pteridinas/química Pterinas/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; REVIEW [Nm] Nome de substância: 0 (Coenzymes); 0 (Metalloproteins); 0 (Organophosphorus Compounds); 0 (Pteridines); 0 (Pterins); 4X7K2681Y7 (cyclic pyranopterin monophosphate); 73508-07-3 (molybdenum cofactor); 81AH48963U (Molybdenum); EC 3.4.- (Metalloexopeptidases) [Em] Mês de entrada: 1307 [Cu] Atualização por classe: 171116 [Lr] Data última revisão: 171116 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 130330 [St] Status: MEDLINE [do] DOI: 10.1074/jbc.R113.455311

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[PMID]: 23192850 [Au] Autor: Tetreau G; Stalinski R; David JP; Després L [Ad] Endereço: Laboratoire d'Ecologie Alpine, LECA-UMR 5553, Université de Grenoble 1, Grenoble Cedex, France. guillaume.tetreau@gmail.com [Ti] Título: Increase in larval gut proteolytic activities and Bti resistance in the Dengue fever mosquito. [So] Source: Arch Insect Biochem Physiol;82(2):71-83, 2013 Feb. [Is] ISSN: 1520-6327 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: The bioinsecticide Bacillus thuringiensis var. israelensis (Bti) is increasingly used worldwide for mosquito control. Although no established resistance to Bti has been described in the field so far, a resistant Aedes aegypti strain (LiTOX strain) was selected in the laboratory using field-collected leaf litter containing Bti toxins. This selected strain exhibits a moderate resistance level to Bti, but a high resistance level to individual Cry toxins. As Bti contains four different toxins, generalist resistance mechanisms affecting mosquito tolerance to different toxins were expected in the resistant strain. In the present work, we show that the resistant strain exhibits an increase of various gut proteolytic activities including trypsins, leucine-aminopeptidases, and carboxypeptidase A activities. These elevated proteolytic activities resulted in a faster activation of Cry4Aa protoxins while Cry4Ba or Cry11Aa were not affected. These results suggest that changes in proteolytic activities may contribute to Bti resistance in mosquitoes together with other mechanisms. [Mh] Termos MeSH primário: Aedes/enzimologia Aedes/microbiologia Bacillus thuringiensis Proteínas de Bactérias Endotoxinas Proteínas Hemolisinas Controle Biológico de Vetores [Mh] Termos MeSH secundário: Aedes/crescimento & desenvolvimento Animais Trato Gastrointestinal/enzimologia Proteínas de Insetos/metabolismo Larva/enzimologia Larva/crescimento & desenvolvimento Larva/microbiologia Metaloexopeptidases/metabolismo Proteólise Serina Endopeptidases/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T [Nm] Nome de substância: 0 (Bacterial Proteins); 0 (Endotoxins); 0 (Hemolysin Proteins); 0 (Insect Proteins); 0 (insecticidal crystal protein, Bacillus Thuringiensis); EC 3.4.- (Metalloexopeptidases); EC 3.4.21.- (Serine Endopeptidases) [Em] Mês de entrada: 1305 [Cu] Atualização por classe: 130109 [Lr] Data última revisão: 130109 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 121130 [St] Status: MEDLINE [do] DOI: 10.1002/arch.21076

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[PMID]: 21794094 [Au] Autor: Prajapati SC; Chauhan SS [Ad] Endereço: Department of Biochemistry, All India Institute of Medical Sciences, New Delhi, India. [Ti] Título: Dipeptidyl peptidase III: a multifaceted oligopeptide N-end cutter. [So] Source: FEBS J;278(18):3256-76, 2011 Sep. [Is] ISSN: 1742-4658 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Dipeptidyl peptidase III (DPP III), the sole member and representative of the M49 family of metallopeptidases, is a zinc-dependent aminopeptidase. It sequentially hydrolyses dipeptides from the N-terminal of oligopeptides ranging from three to 10 amino acid residues. Although implicated in an array of pathophysiological phenomena, the precise function of this peptidase is still unclear. However, a number of studies advocate its contribution in terminal stages of protein turnover. Altered expression of DPP III which suggests its involvement in primary ovarian carcinoma, oxidative stress (Nrf2 nuclear localization), pain, inflammation and cataractogenesis has recently led to resurgence of interest in delineating the role of the peptidase in these pathophysiological processes. This review article intends to bring forth the latest updates in this arena which may serve as a base for future studies on the peptidase. [Mh] Termos MeSH primário: Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo Oligopeptídeos/metabolismo [Mh] Termos MeSH secundário: Animais Biocatálise Dipeptidil Peptidases e Tripeptidil Peptidases/antagonistas & inibidores Dipeptidil Peptidases e Tripeptidil Peptidases/química Dipeptidil Peptidases e Tripeptidil Peptidases/genética Ativação Enzimática Seres Humanos Metaloexopeptidases/química Metaloexopeptidases/metabolismo Estresse Oxidativo Inibidores de Proteases Conformação Proteica Transporte Proteico Especificidade por Substrato Zinco/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; REVIEW [Nm] Nome de substância: 0 (Oligopeptides); 0 (Protease Inhibitors); EC 3.4.- (Metalloexopeptidases); EC 3.4.14.- (Dipeptidyl-Peptidases and Tripeptidyl-Peptidases); EC 3.4.14.4 (dipeptidyl peptidase III); J41CSQ7QDS (Zinc) [Em] Mês de entrada: 1111 [Cu] Atualização por classe: 131121 [Lr] Data última revisão: 131121 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 110729 [St] Status: MEDLINE [do] DOI: 10.1111/j.1742-4658.2011.08275.x

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[PMID]: 20510929 [Au] Autor: Sycuro LK; Pincus Z; Gutierrez KD; Biboy J; Stern CA; Vollmer W; Salama NR [Ad] Endereço: Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA 98195, USA. [Ti] Título: Peptidoglycan crosslinking relaxation promotes Helicobacter pylori's helical shape and stomach colonization. [So] Source: Cell;141(5):822-33, 2010 May 28. [Is] ISSN: 1097-4172 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: The mechanisms by which bacterial cells generate helical cell shape and its functional role are poorly understood. Helical shape of the human pathogen Helicobacter pylori may facilitate penetration of the thick gastric mucus where it replicates. We identified four genes required for helical shape: three LytM peptidoglycan endopeptidase homologs (csd1-3) and a ccmA homolog. Surrounding the cytoplasmic membrane of most bacteria, the peptidoglycan (murein) sacculus is a meshwork of glycan strands joined by peptide crosslinks. Intact cells and isolated sacculi from mutants lacking any single csd gene or ccmA formed curved rods and showed increased peptidoglycan crosslinking. Quantitative morphological analyses of multiple-gene deletion mutants revealed each protein uniquely contributes to a shape-generating pathway. This pathway is required for robust colonization of the stomach in spite of normal directional motility. Our findings suggest that the coordinated action of multiple proteins relaxes peptidoglycan crosslinking, enabling helical cell curvature and twist. [Mh] Termos MeSH primário: Infecções por Helicobacter/microbiologia Helicobacter pylori/citologia Helicobacter pylori/patogenicidade Peptidoglicano/metabolismo Estômago/microbiologia [Mh] Termos MeSH secundário: Animais Proteínas da Membrana Bacteriana Externa/genética Proteínas da Membrana Bacteriana Externa/metabolismo Endopeptidases/metabolismo Feminino Helicobacter pylori/enzimologia Helicobacter pylori/genética Metaloexopeptidases/metabolismo Camundongos Camundongos Endogâmicos C57BL Camundongos Knockout Organismos Livres de Patógenos Específicos [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S. [Nm] Nome de substância: 0 (Bacterial Outer Membrane Proteins); 0 (CcmA protein, bacteria); 0 (Peptidoglycan); 0 (peptidoglycan endopeptidase); EC 3.4.- (Endopeptidases); EC 3.4.- (Metalloexopeptidases) [Em] Mês de entrada: 1006 [Cu] Atualização por classe: 161122 [Lr] Data última revisão: 161122 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 100601 [St] Status: MEDLINE [do] DOI: 10.1016/j.cell.2010.03.046

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[PMID]: 20211192 [Au] Autor: Thyagarajan B; Potian JG; Garcia CC; Hognason K; Capková K; Moe ST; Jacobson AR; Janda KD; McArdle JJ [Ad] Endereço: Department of Pharmacology and Physiology, UMDNJ - New Jersey Medical School, Newark, NJ 07103, USA. [Ti] Título: Effects of hydroxamate metalloendoprotease inhibitors on botulinum neurotoxin A poisoned mouse neuromuscular junctions. [So] Source: Neuropharmacology;58(8):1189-98, 2010 Jun. [Is] ISSN: 1873-7064 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Currently the only therapy for botulinum neurotoxin A (BoNT/A) poisoning is antitoxin. Antidotes that are effective after BoNT/A has entered the motor nerve terminals would dramatically benefit BoNT/A therapy. Inhibition of proteolytic activity of BoNT/A light chain by metalloendoprotease inhibitors (MEIs) is under development. We tested the effects of MEIs on in vitro as well as in vivo BoNT/A poisoned mouse nerve-muscle preparations (NMPs). The K(i) for inhibition of BoNT/A metalloendoprotease was 0.40 and 0.36 muM, respectively, for 2,4-dichlorocinnamic acid hydroxamate (DCH) and its methyl derivative, ABS 130. Acute treatment of nerve-muscle preparations with 10 pM BoNT/A inhibited nerve-evoked muscle twitches, reduced mean quantal content, and induced failures of endplate currents (EPCs). Bath application of 10 muM DCH or 5 muM ABS 130 reduced failures, increased the quantal content of EPCs, and partially restored muscle twitches after a delay of 40-90 min. The restorative effects of DCH and ABS 130, as well as 3,4 diaminopyridine (DAP) on twitch tension were greater at 22 degrees C compared to 37 degrees C. Unlike DAP, neither DCH nor ABS 130 increased Ca(2+) levels in cholinergic Neuro 2a cells. Injection of MEIs into mouse hind limbs before or after BoNT/A injection neither prevented the toe spread reflex inhibition nor improved muscle functions. We suggest that hydroxamate MEIs partially restore neurotransmission of acutely BoNT/A poisoned nerve-muscle preparations in vitro in a temperature dependent manner without increasing the Ca(2+) levels within motor nerve endings. [Mh] Termos MeSH primário: Antídotos/farmacologia Toxinas Botulínicas Tipo A/envenenamento Cinamatos/farmacologia Ácidos Hidroxâmicos/farmacologia Metaloexopeptidases/antagonistas & inibidores Junção Neuromuscular/efeitos dos fármacos [Mh] Termos MeSH secundário: 4-Aminopiridina/análogos & derivados 4-Aminopiridina/farmacologia Acetilcolina/metabolismo Animais Cálcio/metabolismo Linhagem Celular Tumoral Técnicas In Vitro Camundongos Contração Muscular/efeitos dos fármacos Músculo Esquelético/efeitos dos fármacos Músculo Esquelético/fisiopatologia Junção Neuromuscular/metabolismo Junção Neuromuscular/fisiopatologia Reflexo/efeitos dos fármacos [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL [Nm] Nome de substância: 0 (2,4-dichlorocinnamic acid hydroxamate); 0 (ABS 130); 0 (Antidotes); 0 (Cinnamates); 0 (Hydroxamic Acids); BH3B64OKL9 (4-Aminopyridine); EC 3.4.- (Metalloexopeptidases); EC 3.4.24.69 (Botulinum Toxins, Type A); N9YNS0M02X (Acetylcholine); RU4S6E2G0J (3,4-diaminopyridine); SY7Q814VUP (Calcium) [Em] Mês de entrada: 1007 [Cu] Atualização por classe: 161203 [Lr] Data última revisão: 161203 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 100310 [St] Status: MEDLINE [do] DOI: 10.1016/j.neuropharm.2010.02.014

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MEDLINE

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[PMID]: 20116858 [Au] Autor: Li X; Hayik SA; Merz KM [Ad] Endereço: Department of Chemistry and the Quantum Theory Project, 2328 New Physics Building, PO Box 118435, University of Florida, Gainesville, FL 32611-8435, USA. [Ti] Título: QM/MM X-ray refinement of zinc metalloenzymes. [So] Source: J Inorg Biochem;104(5):512-22, 2010 May. [Is] ISSN: 1873-3344 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Zinc metalloenzymes play an important role in biology. However, due to the limitation of molecular force field energy restraints used in X-ray refinement at medium or low resolutions, the precise geometry of the zinc coordination environment can be difficult to distinguish from ambiguous electron density maps. Due to the difficulties involved in defining accurate force fields for metal ions, the QM/MM (quantum-mechanical/molecular-mechanical) method provides an attractive and more general alternative for the study and refinement of metalloprotein active sites. Herein we present three examples that indicate that QM/MM based refinement yields a superior description of the crystal structure based on R and R(free) values and on the inspection of the zinc coordination environment. It is concluded that QM/MM refinement is an useful general tool for the improvement of the metal coordination sphere in metalloenzyme active sites. [Mh] Termos MeSH primário: Metaloexopeptidases/química Conformação Proteica Zinco/química [Mh] Termos MeSH secundário: Álcool Desidrogenase/química Domínio Catalítico Cristalografia por Raios X Proteínas Fúngicas/química Seres Humanos Modelos Moleculares Dados de Sequência Molecular Estrutura Molecular Teoria Quântica Termodinâmica [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL [Nm] Nome de substância: 0 (Fungal Proteins); EC 1.1.1.1 (Alcohol Dehydrogenase); EC 3.4.- (Metalloexopeptidases); J41CSQ7QDS (Zinc) [Em] Mês de entrada: 1006 [Cu] Atualização por classe: 170220 [Lr] Data última revisão: 170220 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 100202 [St] Status: MEDLINE [do] DOI: 10.1016/j.jinorgbio.2009.12.022

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