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Sovic, Michael G. - One of the best experts on this subject based on the ideXlab platform.
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Venomics of new world pit vipers: genus-wide comparisons of venom proteomes across Agkistrodon
Journal of Proteomics vol 96 p.103-116, 2014Co-Authors: Lomonte Bruno, Gutiérrez, José María, Tsai Wan-chih, Sanz Libia, Mora-obando Diana, Fry, Bryan G., Gibbs H. Lisle, Ureña Diaz, Juan M., Sánchez Elda, Sovic, Michael G.Abstract:artículo (arbitrado) -- Universidad de Costa Rica. Instituto de Investigaciones Clodomiro Picado, 2013. Este documento es privado debido a limitaciones de derechos de autor.Wereport a genus-wide comparison of venomproteomevariation acrossNewWorld pit vipers in the genus Agkistrodon. Despite the wide variety of habitats occupied by this genus and that all its taxa feed on diverse species of vertebrates and invertebrate prey, the venom proteomes of copperheads, cottonmouths, and cantils are remarkably similar, both in the type and relative abundance of their different toxin families. The venoms from all the eleven species and subspecies sampled showed relatively similar proteolytic and PLA2 activities. In contrast, quantitative differences were observed in hemorrhagic and myotoxic activities in mice. The highest myotoxic activity was observed with the venoms of A. b. bilineatus, followed by A. p. piscivorus, whereas the venoms of A. c. contortrix and A. p. leucostoma induced the lowest myotoxic activity. The venom of Agkistrodon bilineatus showed the highest hemorrhagic activity and A. c. contortrix the lowest. Compositional and toxicological analyses agree with clinical observations of envenomations by Agkistrodon in the USA and Central America. A comparative analysis of Agkistrodon shows that venom divergence tracks phylogeny of this genus to a greater extent than in Sistrurus rattlesnakes, suggesting that the distinct natural histories of Agkistrodon and Sistrurus clades may have played a key role in molding the patterns of evolution of their venom protein genes.Funding for the research described in this paper was provided by grants BFU2010-17373 from the Ministerio de Ciencia é Innovación (currently, Ministerio de Economía y Competitividad), Madrid; PROMETEO/2010/005 from the Generalitat Valenciana; CRUSA-CSIC (2009CR0021); CYTED (project BIOTOX P211RT0412); Vicerrectoría de Investigación, UCR (project 741-B2-652); and was also supported by FEES-CONARE (Costa Rica) and by NCRR/BMRG, Viper Resource Grant #s 8P40OD01960-10 and 3P40OD01096-10S1 (NNTRC, Texas A&M University-Kingsville, Dr. Sánchez) and the Robert A. Welch Foundation Department Grant #AC-0006 (TAMUK-Department of Chemistry). BGF was funded by the Australian Research Council.UCR::Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP
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Venomics of new world pit vipers: Genus-wide comparisons of venom proteomes across Agkistrodon
'Elsevier BV', 2014Co-Authors: Lomonte Bruno, Gutiérrez, José María, Tsai Wan-chih, Urena-diaz, Juan Manuel, Sanz Libia, Mora-obando Diana, Sanchez, Elda E., Fry, Bryan G., Gibbs H. Lisle, Sovic, Michael G.Abstract:We report a genus-wide comparison of venom proteome variation across New World pit vipers in the genus Agkistrodon. Despite the wide variety of habitats occupied by this genus and that all its taxa feed on diverse species of vertebrates and invertebrate prey, the venom proteomes of copperheads, cottonmouths, and cantils are remarkably similar, both in the type and relative abundance of their different toxin families. The venoms from all the eleven species and subspecies sampled showed relatively similar proteolytic and PLA2 activities. In contrast, quantitative differences were observed in hemorrhagic and myotoxic activities in mice. The highest myotoxic activity was observed with the venoms of A. b. bilineatus, followed by A. p. piscivorus, whereas the venoms of A. c. contortrix and A. p. leucostoma induced the lowest myotoxic activity. The venoms of Agkistrodon bilineatus subspecies showed the highest hemorrhagic activity and A. c. contortrix the lowest. Compositional and toxicological analyses agree with clinical observations of envenomations by Agkistrodon in the USA and Central America. A comparative analysis of Agkistrodon shows that venom divergence tracks phylogeny of this genus to a greater extent than in Sistrurus rattlesnakes, suggesting that the distinct natural histories of Agkistrodon and Sistrurus clades may have played a key role in molding the patterns of evolution of their venom protein genes. Biological significance: A deep understanding of the structural and functional profiles of venoms and of the principles governing the evolution of venomous systems is a goal of venomics. Isolated proteomics analyses have been conducted on venoms from many species of vipers and pit vipers. However, making sense of these large inventories of data requires the integration of this information across multiple species to identify evolutionary and ecological trends. Our genus-wide venomics study provides a comprehensive overview of the toxic arsenal across Agkistrodon and a ground for understanding the natural histories of, and clinical observations of envenomations by, species of this genus
Izidoro, Luiz Fernando Moreira - One of the best experts on this subject based on the ideXlab platform.
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Caracterização bioquímica e funcional de uma nova L-aminoácido oxidase isolada da peçonha da serpente Bothrops pirajai
Universidade Federal de Uberlândia, 2007Co-Authors: Izidoro, Luiz Fernando MoreiraAbstract:Neste trabalho nós descrevemos o isolamento de uma nova L-aminoácido oxidase (LAAO) referida como BpirLAAO-I, do veneno da serpente Bothrops pirajai, a qual foi altamente purificada usando uma combinação de passos cromatográficos, como a exclusão molecular, afinidade e interação hidrofóbica. BpirLAAO-I é uma glicoproteína ácida homodimérica (massa molecular aproximado de 130.000 Da e ponto isoelétrico de 4,9), com alta especificidade por aminoácidos hidrofóbicos/aromáticos, cuja desglicosilação não altera sua atividade enzimática. A seqüência N-terminal dos primeiros 49 resíduos de aminoácidos da LAAO apresentou alta similaridade entre a seqüência de outras LAAOs: Bothrops spp, Crotalus spp, Calloselasma rhosdostoma, Agkistrondon app, Trimeresurus spp, Pseudechis australis, Oxyuramus scutellatus and Notechis scutatus. BpirLAAO-I induziu agregação plaquetária tempo dependente, edema em pata de camundongo, atividade citotóxica contra Escherichia. Coli, Pseudomonas aeruginosa, Leishmania sp e células tumorais e também típica fragmentação em DNA de fago (M13mp18). Agregação plaquetária e atividades leishmanicida e antitumoral foram reduzidas na presença de catalase. BpirLAAO-I é uma proteína multifuncional com promissoras aplicações biotecnológica e medica.In this work we describe the isolation of a new L-amino acid oxidase (LAAO) referred to as BpirLAAO-I from Bothrops pirajai snake venom, which was highly purified using a combination of molecular exclusion, affinity and hydrophobic chromatography steps. BpirLAAO-I is a homodimeric acidic glycoprotein (approximate Mr and pI of 130,000 and 4.9, respectively), that displays a high specificity towards hydrophobic/aromatic amino acid residues while deglycosylation does not alter its enzymatic activity. The N-terminal LAAO sequence of its first 49 amino acids presented a similarity and other LAAOs from: Bothrops spp, Crotalus spp, Calloselasma rhosostoma, Agkistrodon spp, Trimeresurus spp, Pseudechis australis, Oxyuranus scutellatus, and Notechis scutatus. BpirLAAO-I induces time-dependent platelet aggregation, mouse paw edema, cytotoxic activity against Escherichia coli, Pseudomonas aeruginosa, Leishmania sp and tumor cells, and also a typical fago (M13mp18) DNA fragmentation. Platelet aggregation, leishmanicidal and antitumoral activities were reduced by catalase. Thus, BpirLAAO-I is a multifunctional protein with promising biotechnological and medical applications
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Caracterização bioquímica e funcional de uma nova L-aminoácido oxidase isolada da peçonha da serpente Bothrops pirajai
'EDUFU - Editora da Universidade Federal de Uberlandia', 2007Co-Authors: Izidoro, Luiz Fernando MoreiraAbstract:In this work we describe the isolation of a new L-amino acid oxidase (LAAO) referred to as BpirLAAO-I from Bothrops pirajai snake venom, which was highly purified using a combination of molecular exclusion, affinity and hydrophobic chromatography steps. BpirLAAO-I is a homodimeric acidic glycoprotein (approximate Mr and pI of 130,000 and 4.9, respectively), that displays a high specificity towards hydrophobic/aromatic amino acid residues while deglycosylation does not alter its enzymatic activity. The N-terminal LAAO sequence of its first 49 amino acids presented a similarity and other LAAOs from: Bothrops spp, Crotalus spp, Calloselasma rhosostoma, Agkistrodon spp, Trimeresurus spp, Pseudechis australis, Oxyuranus scutellatus, and Notechis scutatus. BpirLAAO-I induces time-dependent platelet aggregation, mouse paw edema, cytotoxic activity against Escherichia coli, Pseudomonas aeruginosa, Leishmania sp and tumor cells, and also a typical fago (M13mp18) DNA fragmentation. Platelet aggregation, leishmanicidal and antitumoral activities were reduced by catalase. Thus, BpirLAAO-I is a multifunctional protein with promising biotechnological and medical applications.Doutor em Genética e BioquímicaNeste trabalho nós descrevemos o isolamento de uma nova L-aminoácido oxidase (LAAO) referida como BpirLAAO-I, do veneno da serpente Bothrops pirajai, a qual foi altamente purificada usando uma combinação de passos cromatográficos, como a exclusão molecular, afinidade e interação hidrofóbica. BpirLAAO-I é uma glicoproteína ácida homodimérica (massa molecular aproximado de 130.000 Da e ponto isoelétrico de 4,9), com alta especificidade por aminoácidos hidrofóbicos/aromáticos, cuja desglicosilação não altera sua atividade enzimática. A seqüência N-terminal dos primeiros 49 resíduos de aminoácidos da LAAO apresentou alta similaridade entre a seqüência de outras LAAOs: Bothrops spp, Crotalus spp, Calloselasma rhosdostoma, Agkistrondon app, Trimeresurus spp, Pseudechis australis, Oxyuramus scutellatus and Notechis scutatus. BpirLAAO-I induziu agregação plaquetária tempo dependente, edema em pata de camundongo, atividade citotóxica contra Escherichia. Coli, Pseudomonas aeruginosa, Leishmania sp e células tumorais e também típica fragmentação em DNA de fago (M13mp18). Agregação plaquetária e atividades leishmanicida e antitumoral foram reduzidas na presença de catalase. BpirLAAO-I é uma proteína multifuncional com promissoras aplicações biotecnológica e medica
R K Arni - One of the best experts on this subject based on the ideXlab platform.
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crystallization and preliminary x ray crystallographic studies of protac a commercial protein c activator isolated from Agkistrodon contortrix contortrix venom
Biochimica et Biophysica Acta, 2005Co-Authors: M T Murakami, R K ArniAbstract:Abstract The protein C pathway plays an important role in the control and regulation of the blood coagulation cascade and prevents the propagation of the clotting process on the endothelium surface. In physiological systems, protein C activation is catalyzed by thrombin, which requires thrombomodulin as a cofactor. The protein C activator from Agkistrodon contortrix contortrix acts directly on the zymogen of protein C converting it into the active form, independently of thrombomodulin. Suitable crystals of the protein C activator from Agkistrodon contortrix contortrix were obtained from a solution containing 2 M ammonium sulfate as the precipitant and these crystals diffracted to 1.95 A resolution at a synchrotron beamline. The crystalline array belongs to the monoclinic space group C2 with unit cell dimensions a = 80.4, b = 63.3 and c = 48.2 A, α = γ = 90.0° and β = 90.8°.
Yuancong Zhou - One of the best experts on this subject based on the ideXlab platform.
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©Institute of Biochemistry and Cell Biology, SIBS, CAS Shedaoenase, a Novel Fibrinogenase from the Venom of
2015Co-Authors: Agkistrodon Shedaoenthesis Zhao, Hao-mang Jiao, Li-xia Yang, Yuancong ZhouAbstract:Abstract Shedaoenase, a serine protease, was isolated from the venom of Agkistrodon shedaoenthesis Zhao with an apparent molecular mass of 36 kDa. It was purified by affinity chromatography on arginine Sepharose 4B column and anion exchange on Mono Q fast protein liquid chromatography. Shedaoenase preferentially cleaved the Aα-chain of human fibrinogen and slowly digested the Ββ-chain. It also showed arginyl esterase activity using Nα-benzoyl-L-arginine ethyl ester as a substrate, and some synthetic chromogentic substrates, such as Chromozym PL, S-2266, and S-2160, could also be hydrolyzed. The enzyme activity of shedaoenase could be completely inhibited by phenylmethylsulphonylfluoride and could be little inhibited by the chelating reagent EDTA. The N-terminal sequence of shedaoenase was determined, and its full-length cDNA encoding a protein of 238 amino acid residues was cloned by reverse transcription-polymerase chain reaction from the total mRNA extracted from the snake venom gland. The deduced primary sequence of shedaoenase shares significant homology with other snake venom serine proteases. Key words Agkistrodon shedaoenthesis Zhao; fibrinogenlytic activity; serine proteas
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purification and characterization of platelet aggregation inhibitor component from venom of Agkistrodon halys pallas
Journal of Experimental Hematology, 2004Co-Authors: Ping Liu, Qian Jin, Yiqing Wang, Hong Zhu, Yuancong ZhouAbstract:Snake venom proteins,particularly from the viper and elapid families, have been known to contain a number of platelet active components including what cause platelet aggregation or inhibit platelet aggregation. Some of them have potential clinical usefulness for the treatment of human hemorrhagic or thrombotic disease. Agkistrodon halys pallas belonging to viper family is only growing in China. The aim of this study was to purify a human platelet aggregation inhibitor from venom of Agkistrodon halys pallas and determine its biochemical character. Whether a component could inhibit human platelet aggregation was act as a method to follow the tracks of the protein. Crude venom of Agkistrodon halys pallas was loaded onto a DEAE-Sepharose CL-6B chromatography column could gain 6 peaks. A platelet inhibitor with molecular mass of 65 kD on SDS-PAGE, was purified from peak 2 by Sephadex G-75 gel filtration and SP-Sepharose, Mono Q on FPLC. It could inhibit human platelet aggregation induced by ADP, collagen without activities of phospholipase A2, esterase, fibrinogenolytic. It is concluded that a platelet inhibitor can be isolated and purified from venom of Agkistrodon halys pallas and its inhibition of platelet aggregation is does-dependent.
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structures of cadmium binding acidic phospholipase a2 from the venom of Agkistrodon halys pallas at 1 9a resolution
Biochemical and Biophysical Research Communications, 2003Co-Authors: Tao Jiang, Yuancong Zhou, Z LinAbstract:Abstract Phospholipase A2 coordinates Ca2+ ion through three carbonyl oxygen atoms of residues 28, 30, and 32, two carboxyl oxygen atoms of residue Asp49, and two (or one) water molecules, forming seven (or six) coordinate geometry of Ca2+ ligands. Two crystal structures of cadmium-binding acidic phospholipase A2 from the venom of Agkistrodon halys Pallas (i.e., Agkistrodon blomhoffii brevicaudus) at different pH values (5.9 and 7.4) were determined to 1.9 A resolution by the isomorphous difference Fourier method. The well-refined structures revealed that a Cd2+ ion occupied the position expected for a Ca2+ ion, and that the substitution of Cd2+ for Ca2+ resulted in detectable changes in the metal-binding region: one of the carboxyl oxygen atoms from residue Asp49 was farther from the metal ion while the other one was closer and there were no water molecules coordinating to the metal ion. Thus the Cd2+-binding region appears to have four coordinating oxygen ligands. The cadmium binding to the enzyme induced no other significant conformational change in the enzyme molecule elsewhere. The mechanism for divalent cadmium cation to support substrate binding but not catalysis is discussed.
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expression purification and biochemical characterization of a recombinant phospholipase a2 with anticoagulant activity from Agkistrodon halys pallas
Journal of Natural Toxins, 2001Co-Authors: Xiaolan Zhong, J Liu, Yuancong ZhouAbstract:A cloned cDNA encoding a PLA2 from Agkistrodon halys Pallas was found to have conservative residues Glu53 and Trp70 but with Lys56 and Lys67 substituted by Thr56 and Asp67, respectively, when compared with sequences of other class II PLA2 with anticoagulant activity. It was inserted into a temperature-sensitive bacterial expression vector and effectively expressed in Escherichia coli RR1. The protein was produced as insoluble inclusion bodies and recovered by centrifugation after enzyme digestion. By washing to partial purification, the expression product was refolded and was purified by FPLC superose 12 to appear as a single band in SDS-PAGE. The recombinant protein proved to have obvious enzymatic, anticoagulant and hemolytic activities, which were removed after modification by p-BPB. These findings suggest that the pharmacological activities of this recombinant PLA2 may be related to its catalytic activity and warrant further research on the structure-function relationships of the pharmacological site of the PLA2 from Agkistrodon halys Pallas.
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expression of the apla 2 gene from Agkistrodon halys pallas
Acta Biochimica et Biophysica Sinica, 1998Co-Authors: Xiaojin Liu, Hua Pan, Guanzhen Yang, Yuancong ZhouAbstract:The APLA(2) gene from Agkistrodon halys Pallas has been cloned into the expression plasmid pBLMVL2 and expressed in E. coli RR1. The molecular weight of the expressed product is approximately 14 kD as shown by SDS-PAGE, its expression level is about 30% of the total cellular proteins. The protein was produced as insoluble inclusion bodies. After partially purified by washing the inclusion bodies, the product was denatured and refolded into active form. Then, the expressed APLA(2) was purified by FPLC Superose (TM) 12 and was a single band as shown by SDS-PAGE. The purified expressed protein had specific activity as the native enzyme and cross-reacted with antisera prepared against the native enzyme. The successful expression of the APLA(2) gene from Agkistrodon halys Pallas provides a good basis for further structure-function studies.
Lomonte Bruno - One of the best experts on this subject based on the ideXlab platform.
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Venomics of new world pit vipers: genus-wide comparisons of venom proteomes across Agkistrodon
Journal of Proteomics vol 96 p.103-116, 2014Co-Authors: Lomonte Bruno, Gutiérrez, José María, Tsai Wan-chih, Sanz Libia, Mora-obando Diana, Fry, Bryan G., Gibbs H. Lisle, Ureña Diaz, Juan M., Sánchez Elda, Sovic, Michael G.Abstract:artículo (arbitrado) -- Universidad de Costa Rica. Instituto de Investigaciones Clodomiro Picado, 2013. Este documento es privado debido a limitaciones de derechos de autor.Wereport a genus-wide comparison of venomproteomevariation acrossNewWorld pit vipers in the genus Agkistrodon. Despite the wide variety of habitats occupied by this genus and that all its taxa feed on diverse species of vertebrates and invertebrate prey, the venom proteomes of copperheads, cottonmouths, and cantils are remarkably similar, both in the type and relative abundance of their different toxin families. The venoms from all the eleven species and subspecies sampled showed relatively similar proteolytic and PLA2 activities. In contrast, quantitative differences were observed in hemorrhagic and myotoxic activities in mice. The highest myotoxic activity was observed with the venoms of A. b. bilineatus, followed by A. p. piscivorus, whereas the venoms of A. c. contortrix and A. p. leucostoma induced the lowest myotoxic activity. The venom of Agkistrodon bilineatus showed the highest hemorrhagic activity and A. c. contortrix the lowest. Compositional and toxicological analyses agree with clinical observations of envenomations by Agkistrodon in the USA and Central America. A comparative analysis of Agkistrodon shows that venom divergence tracks phylogeny of this genus to a greater extent than in Sistrurus rattlesnakes, suggesting that the distinct natural histories of Agkistrodon and Sistrurus clades may have played a key role in molding the patterns of evolution of their venom protein genes.Funding for the research described in this paper was provided by grants BFU2010-17373 from the Ministerio de Ciencia é Innovación (currently, Ministerio de Economía y Competitividad), Madrid; PROMETEO/2010/005 from the Generalitat Valenciana; CRUSA-CSIC (2009CR0021); CYTED (project BIOTOX P211RT0412); Vicerrectoría de Investigación, UCR (project 741-B2-652); and was also supported by FEES-CONARE (Costa Rica) and by NCRR/BMRG, Viper Resource Grant #s 8P40OD01960-10 and 3P40OD01096-10S1 (NNTRC, Texas A&M University-Kingsville, Dr. Sánchez) and the Robert A. Welch Foundation Department Grant #AC-0006 (TAMUK-Department of Chemistry). BGF was funded by the Australian Research Council.UCR::Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP
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Venomics of new world pit vipers: Genus-wide comparisons of venom proteomes across Agkistrodon
'Elsevier BV', 2014Co-Authors: Lomonte Bruno, Gutiérrez, José María, Tsai Wan-chih, Urena-diaz, Juan Manuel, Sanz Libia, Mora-obando Diana, Sanchez, Elda E., Fry, Bryan G., Gibbs H. Lisle, Sovic, Michael G.Abstract:We report a genus-wide comparison of venom proteome variation across New World pit vipers in the genus Agkistrodon. Despite the wide variety of habitats occupied by this genus and that all its taxa feed on diverse species of vertebrates and invertebrate prey, the venom proteomes of copperheads, cottonmouths, and cantils are remarkably similar, both in the type and relative abundance of their different toxin families. The venoms from all the eleven species and subspecies sampled showed relatively similar proteolytic and PLA2 activities. In contrast, quantitative differences were observed in hemorrhagic and myotoxic activities in mice. The highest myotoxic activity was observed with the venoms of A. b. bilineatus, followed by A. p. piscivorus, whereas the venoms of A. c. contortrix and A. p. leucostoma induced the lowest myotoxic activity. The venoms of Agkistrodon bilineatus subspecies showed the highest hemorrhagic activity and A. c. contortrix the lowest. Compositional and toxicological analyses agree with clinical observations of envenomations by Agkistrodon in the USA and Central America. A comparative analysis of Agkistrodon shows that venom divergence tracks phylogeny of this genus to a greater extent than in Sistrurus rattlesnakes, suggesting that the distinct natural histories of Agkistrodon and Sistrurus clades may have played a key role in molding the patterns of evolution of their venom protein genes. Biological significance: A deep understanding of the structural and functional profiles of venoms and of the principles governing the evolution of venomous systems is a goal of venomics. Isolated proteomics analyses have been conducted on venoms from many species of vipers and pit vipers. However, making sense of these large inventories of data requires the integration of this information across multiple species to identify evolutionary and ecological trends. Our genus-wide venomics study provides a comprehensive overview of the toxic arsenal across Agkistrodon and a ground for understanding the natural histories of, and clinical observations of envenomations by, species of this genus