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Talukdar A, Doley R. Identification of poorly immunodepleted phospholipase A 2 (PLA 2) proteins of Bungarus fasciatus venom from Assam, India and evaluation of Indian polyvalent antivenom using third-generation antivenomics. Toxicon 2024; 239:107617. [PMID: 38219916 DOI: 10.1016/j.toxicon.2024.107617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 01/09/2024] [Accepted: 01/12/2024] [Indexed: 01/16/2024]
Abstract
Bungarus fasciatus also referred to as the Banded krait is a snake which possesses venom and belongs to the Elapidae family. It is widely distributed across the Indian subcontinent and South East Asian countries and is responsible for numerous snakebites in the population. B. fasciatus possesses a neurotoxic venom and envenomation by the snake results in significant morbidity and occasional morbidity in the victim if not treated appropriately. In this study, the efficacy of Indian polyvalent antivenom (Premium Serums polyvalent antivenom) was evaluated against the venom of B. fasciatus from Guwahati, Assam (India) employing the Third-generation antivenomics technique followed by identification of venom proteins from three poorly immunodepleted peaks (P5, P6 and P7) using LC-MS/MS analysis. Seven proteins were identified from the three peaks and all these venom proteins belonged to the phospholipase A2 (PLA2) superfamily. The identified PLA2 proteins were corroborated by the in vitro enzymatic activities (PLA2 and Anticoagulant activity) exhibited by the three peaks and previous reports of pathological manifestation in the envenomated victims. Neutralization of enzymatic activities by Premium Serums polyvalent antivenom was also assessed in vitro for crude venom, P5, P6 and P7 which revealed moderate to poor inhibition. Inclusion of venom proteins/peptides, which are non-immunodepleted or poorly immunodepleted, into the immunization mixture of venom used for antivenom production may help in enhancing the efficacy of the polyvalent antivenom.
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Affiliation(s)
- Amit Talukdar
- Molecular Toxinology Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Assam, 784028, India
| | - Robin Doley
- Molecular Toxinology Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Assam, 784028, India.
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2
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Mariani ME, Fidelio GD. Secretory Phospholipases A 2 in Plants. FRONTIERS IN PLANT SCIENCE 2019; 10:861. [PMID: 31354755 PMCID: PMC6635587 DOI: 10.3389/fpls.2019.00861] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/14/2019] [Indexed: 05/17/2023]
Abstract
Secreted phospholipases (sPLA2s) in plants are a growing group of enzymes that catalyze the hydrolysis of sn-2 glycerophospholipids to lysophospholipids and free fatty acids. Until today, around only 20 sPLA2s were reported from plants. This review discusses the newly acquired information on plant sPLA2s including molecular, biochemical, catalytic, and functional aspects. The comparative analysis also includes phylogenetic, evolutionary, and tridimensional structure. The observations with emphasis in Glycine max sPLA2 are compared with the available data reported for all plants sPLA2s and with those described for animals (mainly from pancreatic juice and venoms sources).
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Affiliation(s)
- María Elisa Mariani
- Departamento de Química Biológica, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba, Córdoba, Argentina
- Instituto de Investigaciones Biológicas y Tecnológicas, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Departamento de Fundamentación Biológica, Facultad de Ciencias Agropecuarias, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Gerardo Daniel Fidelio
- Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Investigaciones en Química Biológica de Córdoba, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Córdoba, Córdoba, Argentina
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3
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Abstract
Fourier transform infrared (FTIR) spectroscopy has become one of the major techniques of structural characterization of proteins, peptides, and protein-membrane interactions. While the method does not have the capability of providing the precise, atomic-resolution molecular structure, it is exquisitely sensitive to conformational changes occurring in proteins upon functional transitions or intermolecular interactions. The sensitivity of vibrational frequencies to atomic masses has led to development of "isotope-edited" FTIR spectroscopy, where structural effects in two proteins, one unlabeled and the other labeled with a heavier stable isotope, such as 13C, are resolved simultaneously based on spectral downshift (separation) of the amide I band of the labeled protein. The same isotope effect is used to identify site-specific conformational changes in proteins by site-directed or segmental isotope labeling. Negligible light scattering in the infrared region provides an opportunity to study intermolecular interactions between large protein complexes, interactions of proteins and peptides with lipid vesicles, or protein-nucleic acid interactions without light scattering problems often encountered in ultraviolet spectroscopy. Attenuated total reflection FTIR (ATR-FTIR) is a surface-sensitive version of infrared spectroscopy that has proved useful in studying membrane proteins and lipids, protein-membrane interactions, mechanisms of interfacial enzymes, the structural features of membrane pore forming proteins and peptides, and much more. The purpose of this chapter was to provide a practical guide to analyze protein structure and protein-membrane interactions by FTIR and ATR-FTIR techniques, including procedures of sample preparation, measurements, and data analysis. Basic background information on FTIR spectroscopy, as well as some relatively new developments in structural and functional characterization of proteins and peptides in lipid membranes, is also presented.
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Affiliation(s)
- Suren A Tatulian
- Department of Physics, University of Central Florida, Orlando, FL, USA.
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Abstract
Most interfacial enzymes undergo activation upon membrane binding. Interfacial activation is determined not only by the binding strength but also by the specific mode of protein-membrane interactions, including the angular orientation and membrane insertion of the enzymes. This chapter describes biophysical techniques to quantitatively evaluate membrane binding, orientation, membrane insertion, and activity of secreted phospholipase A2 (PLA2) and lipoxygenase (LO) enzymes. Procedures for recombinant production and purification of human pancreatic PLA2 and human 5-lipoxygenase (5-LO) are also presented. Several methods for measurements of membrane binding of peripheral proteins are described, i.e., fluorescence resonance energy transfer (FRET) from tryptophan or tyrosine residues of the protein to a fluorescent lipid in vesicles, changes in fluorescence of an environment-sensitive fluorescent lipid upon binding of proteins to membranes, and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. These methods produce the apparent binding constant, the protein-to-lipid binding stoichiometry, and the Hill cooperativity coefficient. Experimental procedures for segmental isotope labeling of proteins and determination of the orientation of membrane-bound proteins by polarized ATR-FTIR spectroscopy are described. Furthermore, evaluation of membrane insertion of peripheral proteins by a fluorescence quenching technique is outlined. Combination of the orientation and membrane insertion provides a unique configuration of the protein-membrane complex and hence elucidates certain details of the enzyme function, such as the modes of acquisition of a membrane-residing substrate and product release. Finally, assays for determination of the activities of secreted PLA2, soybean LO, and human 5-LO are described.
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Affiliation(s)
- S A Tatulian
- College of Sciences, University of Central Florida, Orlando, FL, United States.
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Carregari VC, Dai J, Verano-Braga T, Rocha T, Ponce-Soto LA, Marangoni S, Roepstorff P. Revealing the functional structure of a new PLA2 K49 from Bothriopsis taeniata snake venom employing automatic “de novo” sequencing using CID/HCD/ETD MS/MS analyses. J Proteomics 2016; 131:131-139. [DOI: 10.1016/j.jprot.2015.10.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 10/14/2015] [Accepted: 10/15/2015] [Indexed: 11/24/2022]
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6
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Tatulian SA. Structural Dynamics of Insulin Receptor and Transmembrane Signaling. Biochemistry 2015; 54:5523-32. [PMID: 26322622 DOI: 10.1021/acs.biochem.5b00805] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The insulin receptor (IR) is a (αβ)2-type transmembrane tyrosine kinase that plays a central role in cell metabolism. Each αβ heterodimer consists of an extracellular ligand-binding α-subunit and a membrane-spanning β-subunit that comprises the cytoplasmic tyrosine kinase (TK) domain and the phosphorylation sites. The α- and β-subunits are linked via a single disulfide bridge, and the (αβ)2 tetramer is formed by disulfide bonds between the α-chains. Insulin binding induces conformational changes in IR that reach the intracellular β-subunit followed by a protein phosphorylation and activation cascade. Defects in this signaling process, including IR dysfunction caused by mutations, result in type 2 diabetes. Rational drug design aimed at treatment of diabetes relies on knowledge of the detailed structure of IR and the dynamic structural transformations during transmembrane signaling. Recent X-ray crystallographic studies have provided important clues about the mode of binding of insulin to IR, the resulting structural changes and their transmission to the TK domain, but a complete understanding of the structural basis underlying insulin signaling has not been achieved. This review presents a critical analysis of the current status of the structure-function relationship of IR, with a comparative assessment of the other IR family receptors, and discusses potential advancements that may provide insight into the molecular mechanism of insulin signaling.
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Affiliation(s)
- Suren A Tatulian
- Department of Physics, University of Central Florida , 4111 Libra Drive, Orlando, Florida 32816, United States
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Simonato M, Morbiato L, Zorzi V, Caccin P, Fernández J, Massimino ML, Polverino de Laureto P, Tonello F. Production in Escherichia coli, folding, purification and characterization of notexin with wild type sequence and with N-terminal and catalytic site mutations. Toxicon 2014; 88:11-20. [DOI: 10.1016/j.toxicon.2014.06.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 05/31/2014] [Accepted: 06/11/2014] [Indexed: 12/11/2022]
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8
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Lucas M, Gaspar AH, Pallara C, Rojas AL, Fernández-Recio J, Machner MP, Hierro A. Structural basis for the recruitment and activation of the Legionella phospholipase VipD by the host GTPase Rab5. Proc Natl Acad Sci U S A 2014; 111:E3514-23. [PMID: 25114243 PMCID: PMC4151760 DOI: 10.1073/pnas.1405391111] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
A challenge for microbial pathogens is to assure that their translocated effector proteins target only the correct host cell compartment during infection. The Legionella pneumophila effector vacuolar protein sorting inhibitor protein D (VipD) localizes to early endosomal membranes and alters their lipid and protein composition, thereby protecting the pathogen from endosomal fusion. This process requires the phospholipase A1 (PLA1) activity of VipD that is triggered specifically on VipD binding to the host cell GTPase Rab5, a key regulator of endosomes. Here, we present the crystal structure of VipD in complex with constitutively active Rab5 and reveal the molecular mechanism underlying PLA1 activation. An active site-obstructing loop that originates from the C-terminal domain of VipD is repositioned on Rab5 binding, thereby exposing the catalytic pocket within the N-terminal PLA1 domain. Substitution of amino acid residues located within the VipD-Rab5 interface prevented Rab5 binding and PLA1 activation and caused a failure of VipD mutant proteins to target to Rab5-enriched endosomal structures within cells. Experimental and computational analyses confirmed an extended VipD-binding interface on Rab5, explaining why this L. pneumophila effector can compete with cellular ligands for Rab5 binding. Together, our data explain how the catalytic activity of a microbial effector can be precisely linked to its subcellular localization.
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Affiliation(s)
- María Lucas
- Structural Biology Unit, Center for Cooperative Research in Biosciences, 48160 Derio, Spain
| | - Andrew H Gaspar
- Cell Biology and Metabolism Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
| | - Chiara Pallara
- Joint Barcelona Supercomputing Center-Institute for Research in Biomedicine Research Program in Computational Biology, Barcelona Supercomputing Center, 08034 Barcelona, Spain; and
| | - Adriana Lucely Rojas
- Structural Biology Unit, Center for Cooperative Research in Biosciences, 48160 Derio, Spain
| | - Juan Fernández-Recio
- Joint Barcelona Supercomputing Center-Institute for Research in Biomedicine Research Program in Computational Biology, Barcelona Supercomputing Center, 08034 Barcelona, Spain; and
| | - Matthias P Machner
- Cell Biology and Metabolism Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892;
| | - Aitor Hierro
- Structural Biology Unit, Center for Cooperative Research in Biosciences, 48160 Derio, Spain; IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain
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9
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Kar S, Patel MA, Tripathy RK, Bajaj P, Pande AH. Oxidized-phospholipids in reconstituted high density lipoprotein particles affect structure and function of recombinant paraoxonase 1. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:1714-20. [DOI: 10.1016/j.bbalip.2013.08.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 07/31/2013] [Accepted: 08/07/2013] [Indexed: 11/25/2022]
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10
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Siligardi G, Hussain R, Patching SG, Phillips-Jones MK. Ligand- and drug-binding studies of membrane proteins revealed through circular dichroism spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:34-42. [PMID: 23811229 DOI: 10.1016/j.bbamem.2013.06.019] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 06/13/2013] [Accepted: 06/14/2013] [Indexed: 11/15/2022]
Abstract
A great number of membrane proteins have proven difficult to crystallise for use in X-ray crystallographic structural determination or too complex for NMR structural studies. Circular dichroism (CD) is a fast and relatively easy spectroscopic technique to study protein conformational behaviour. In this review examples of the applications of CD and synchrotron radiation CD (SRCD) to membrane protein ligand binding interaction studies are discussed. The availability of SRCD has been an important advancement in recent progress, most particularly because it can be used to extend the spectral region in the far-UV region (important for increasing the accuracy of secondary structure estimations) and for working with membrane proteins available in only small quantities for which SRCD has facilitated molecular recognition studies. Such studies have been accomplished by probing in the near-UV region the local tertiary structure of aromatic amino acid residues upon addition of chiral or non-chiral ligands using long pathlength cells of small volume capacity. In particular, this review describes the most recent use of the technique in the following areas: to obtain quantitative data on ligand binding (exemplified by the FsrC membrane sensor kinase receptor); to distinguish between functionally similar drugs that exhibit different mechanisms of action towards membrane proteins (exemplified by secretory phospholipase A2); and to identify suitable detergent conditions to observe membrane protein-ligand interactions using stabilised proteins (exemplified by the antiseptic transporter SugE). Finally, the importance of characterising in solution the conformational behaviour and ligand binding properties of proteins in both far- and near-UV regions is discussed. This article is part of a Special Issue entitled: Structural and biophysical characterisation of membrane protein-ligand binding.
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Affiliation(s)
- Giuliano Siligardi
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, UK; School of Biological Sciences, University of Liverpool, Liverpool, UK.
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11
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Tatulian SA. Structural characterization of membrane proteins and peptides by FTIR and ATR-FTIR spectroscopy. Methods Mol Biol 2013; 974:177-218. [PMID: 23404277 DOI: 10.1007/978-1-62703-275-9_9] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Fourier transform infrared (FTIR) spectroscopy is widely used in structural characterization of proteins or peptides. While the method does not have the capability of providing the precise, atomic-resolution molecular structure, it is exquisitely sensitive to conformational changes occurring in proteins upon functional transitions or upon intermolecular interactions. Sensitivity of vibrational frequencies to atomic masses has led to development of "isotope-edited" FTIR spectroscopy, where structural effects in two proteins, one unlabeled and the other labeled with a heavier stable isotope, such as (13)C, are resolved simultaneously based on spectral downshift (separation) of the amide I band of the labeled protein. The same isotope effect is used to identify site-specific conformational changes in proteins by site-directed or segmental isotope labeling. Negligible light scattering in the infrared region provides an opportunity to study intermolecular interactions between large protein complexes, interactions of proteins and peptides with lipid vesicles, or protein-nucleic acid interactions without light scattering problems often encountered in ultraviolet spectroscopy. Attenuated total reflection FTIR (ATR-FTIR) is a surface-sensitive version of infrared spectroscopy that has proved useful in studying membrane proteins and lipids, protein-membrane interactions, mechanisms of interfacial enzymes, and molecular architecture of membrane pore or channel forming proteins and peptides. The purpose of this article was to provide a practical guide to analyze protein structure and protein-membrane interactions by FTIR and ATR-FTIR techniques, including procedures of sample preparation, measurements, and data analysis. Basic background information on FTIR spectroscopy, as well as some relatively new developments in structural and functional characterization of proteins and peptides in lipid membranes, are also presented.
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Affiliation(s)
- Suren A Tatulian
- Department of Physics, University of Central Florida, Orlando, FL, USA.
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Kao PH, Lin SR, Hu WP, Chang LS. Naja naja atra and Naja nigricollis cardiotoxins induce fusion of Escherichia coli and Staphylococcus aureus membrane-mimicking liposomes. Toxicon 2012; 60:367-77. [DOI: 10.1016/j.toxicon.2012.04.345] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 03/03/2012] [Accepted: 04/18/2012] [Indexed: 10/28/2022]
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Kar S, Patel MA, Tripathy RK, Bajaj P, Suvarnakar UV, Pande AH. Oxidized phospholipid content destabilizes the structure of reconstituted high density lipoprotein particles and changes their function. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1821:1200-10. [PMID: 22634518 DOI: 10.1016/j.bbalip.2012.05.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2012] [Revised: 05/02/2012] [Accepted: 05/11/2012] [Indexed: 11/16/2022]
Abstract
High density lipoprotein (HDL) particles are made up of lipid and protein constituents and apolipoprotein A-I (apoA-I) is a principal protein component that facilitates various biological activities of HDL particles. Increase in Ox-PL content of HDL particles makes them 'dysfunctional' and such modified HDL particles not only lose their athero-protective properties but also acquire pro-atherogenic and pro-inflammatory functions. The details of Ox-PL-induced alteration in the molecular properties of HDL particles are not clear. Paraoxonase 1 (PON1) is an HDL-associated enzyme that possesses anti-inflammatory and anti-atherogenic properties; and many of the athero-protective functions of HDL are attributed to the associated PON1. In this study we have characterized the physicochemical properties of reconstituted HDL (rHDL) particles containing varying amounts of Ox-PL and have compared their PON1 stimulation capacity. Our results show that increased Ox-PL content (a) modifies the physicochemical properties of the lipid domain of the rHDL particles, (b) decreases the stability and alters the conformation as well as orientation of apoA-I molecules on the rHDL particles, and (c) decreases the PON1 stimulation capacity of the rHDL particles. Our data indicate that the presence of Ox-PLs destabilizes the structure of the HDL particles and modifies their function.
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Affiliation(s)
- Subhabrata Kar
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research, Punjab, India
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Kao PH, Chiou YL, Chen YJ, Lin SR, Chang LS. Guanidination of notexin promotes its phospholipase A(2) activity-independent fusogenicity on vesicles with lipid-supplied negative curvature. Toxicon 2011; 59:47-58. [PMID: 22030836 DOI: 10.1016/j.toxicon.2011.10.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2011] [Revised: 09/27/2011] [Accepted: 10/11/2011] [Indexed: 11/30/2022]
Abstract
To address the requirement of phospholipase A(2) (PLA(2)) activity in membrane fusion events and membrane perturbation activity of notexin and guanidinated notexin (Gu-notexin), the present study was conducted. Notexin and Gu-notexin did not show PLA(2) activity after the removal of Ca(2+) with EDTA. Metal-free notexin and Gu-notexin were found to induce membrane leakage and fusion of phospholipid vesicles. Fusogenic activity of native and modified notexin correlated positively with their membrane-damaging activity underlying the deprivation of PLA(2) activity. Compared with Ca(2+)-bound Gu-notexin, fusogenicity of metal-free Gu-notexin was notably increased by incorporation of cholesterol, cholesterol sulfate, phosphatidylethanolamine, α-tocopherol and phosphatidic acid that supplied negative curvature into phospholipid bilayer. The ability of Gu-notexin to induce membrane fusion of vesicles with lipid-supplied negative curvature was higher than that of notexin regardless of the absence or presence of Ca(2+). Consistently, metal-free Gu-notexin markedly induced membrane fusion of red blood cells (RBCs) compared with metal-free notexin, and fusion activity of metal-free Gu-notexin on cholesterol-depleted RBCs notably reduced. Compared with notexin, Gu-notexin highly induced uptake of calcein-loaded phosphatidylcholine (PC)/cholesterol and PC/cholesterol sulfate vesicles by K562 cells in the presence of EDTA. Taken together, our data suggest that notexin and Gu-notexin could induce vesicle leakage and fusion via a PLA(2) activity-independent mechanism, and guanidination promotes PLA(2) activity-independent fusogenicity of notexin on vesicles with lipid-supplied negative curvature.
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Affiliation(s)
- Pei-Hsiu Kao
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
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15
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Huancahuire-Vega S, Ponce-Soto LA, Martins-de-Souza D, Marangoni S. Biochemical and pharmacological characterization of PhTX-I a new myotoxic phospholipase A2 isolated from Porthidium hyoprora snake venom. Comp Biochem Physiol C Toxicol Pharmacol 2011; 154:108-19. [PMID: 21496495 DOI: 10.1016/j.cbpc.2011.03.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 03/30/2011] [Accepted: 03/31/2011] [Indexed: 01/04/2023]
Abstract
This paper reports the biochemical and pharmacological characterization of a new myotoxic PLA(2) (EC 3.1.1.4) called PhTX-I, purified from Porthidium hyoprora venom by one step analytical chromatography reverse phase HPLC. The homogeneity of the PhTX-I fraction and its molecular mass were initially evaluated by SDS-PAGE and confirmed by MALDI-TOF spectrometry, indicating a molecular mass of 14.249Da and constituted of a single polipeptidic chain. Amino acid sequence was determined by "de novo sequencing," in tandem mass spectrometry, belonging to D49-PLA(2) enzyme class and exhibiting high identity (44-90%) with other myotoxics PLA(2) from snake venoms. The enzymatic investigation showed maximal activity at pH 8 and 35-45°C. This activity was dependent on Ca(2+), other cations (Mg(2+), Mn(2+), Cd(2+) and Zn(2+)) reduced notably the enzymatic activity, suggesting that the arrangement of the catalytic site presents an exclusive structure for Ca(2+). Ex vivo, whole venom and PhTX-I PLA(2) caused blockade of the neuromuscular transmission in young chick biventer cervicis preparations similar to other isolated snake venom toxins from the Bothrops genus. In vivo, both induced local myotoxicity and systemic interleukin-6 response upon intramuscular injection, additionally, induced moderate footpad edema. In vitro, both induced low cytotoxicity in skeletal muscle myoblasts, however PhTX-I PLA(2) was able to lyse myotubes.
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Bacha AGB, Mejdoub H. Proteolytic cleavage of stingray phospholipase A2: isolation and biochemical characterization of an active N-terminal form. Lipids Health Dis 2011; 10:124. [PMID: 21791082 PMCID: PMC3180402 DOI: 10.1186/1476-511x-10-124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Accepted: 07/26/2011] [Indexed: 11/23/2022] Open
Abstract
Background Mammalian GIB-PLA2 are well characterized. In contrast, much less is known about aquatic ones. The aquatic world contains a wide variety of living species and, hence represents a great potential for discovering new lipolytic enzymes. The aim of this study was to check some biochemical and structural properties of a marine stingray phospholipase A2 (SPLA2). Results The effect of some proteolytic enzymes on SPLA2 was checked. Chymotrypsin and trypsin were able to hydrolyze SPLA2 in different ways. In both cases, only N-terminal fragments were accumulated during the hydrolysis, whereas no C-terminal fragment was obtained in either case. Tryptic and chymotryptic attack generated 13 kDa and 12 kDa forms of SPLA2, respectively. Interestingly, the SPLA2 13 kDa form was inactive, whereas the SPLA2 12 kDa form conserved almost its full phospholipase activity. In the absence of bile slats both native and 12kDa SPLA2 failed to catalyse the hydrolysis of PC emulsion. When bile salts were pre-incubated with the substrate, the native kinetic protein remained linear for more than 25 min, whereas the 12 kDa form activity was found to decrease rapidly. Furthermore, The SPLA2 activity was dependent on Ca2+; other cations (Mg2+, Mn2+, Cd2+ and Zn2+) reduced the enzymatic activity notably, suggesting that the arrangement of the catalytic site presents an exclusive structure for Ca2+. Conclusions Although marine and mammal pancreatic PLA2 share a high amino acid sequence homology, polyclonal antibodies directed against SPLA2 failed to recognize mammal PLA2 like the dromedary pancreatic one. Further investigations are needed to identify key residues involved in substrate recognition responsible for biochemical differences between the 2 classes of phospholipases.
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Affiliation(s)
- Abir G Ben Bacha
- Biochemistry Department, Science College, King Saud University, PO Box 22452, 11495 Riyadh, Saudi Arabia.
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Chiou YL, Lin SR, Chang LS. Sphingomyelin modulates interfacial binding of Taiwan cobra phospholipase A2. Chem Phys Lipids 2011; 164:378-85. [DOI: 10.1016/j.chemphyslip.2011.04.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Revised: 04/09/2011] [Accepted: 04/28/2011] [Indexed: 12/28/2022]
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18
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Toyama DDO, Diz Filho EBDS, Cavada BS, da Rocha BAM, de Oliveira SCB, Cotrim CA, Soares VCG, Delatorre P, Marangoni S, Toyama MH. Umbelliferone induces changes in the structure and pharmacological activities of Bn IV, a phospholipase A2 isoform isolated from Bothrops neuwiedi. Toxicon 2011; 57:851-60. [DOI: 10.1016/j.toxicon.2011.02.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Revised: 02/20/2011] [Accepted: 02/22/2011] [Indexed: 10/18/2022]
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19
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Changes in PLA2 activity after interacting with anti-inflammatory drugs and model membranes: evidence for the involvement of tryptophan residues. Chem Phys Lipids 2011; 164:292-9. [DOI: 10.1016/j.chemphyslip.2011.03.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 03/09/2011] [Accepted: 03/11/2011] [Indexed: 11/23/2022]
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20
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Chiou YL, Lin SR, Chang LS. Lipid domain formation modulates activities of snake venom phospholipase A2 enzymes. Toxicon 2010; 56:1362-71. [DOI: 10.1016/j.toxicon.2010.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2010] [Revised: 07/29/2010] [Accepted: 08/02/2010] [Indexed: 11/15/2022]
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Kao PH, Chiou YL, Lin SR, Chang LS. Guanidination of notexin alters its membrane-damaging activity in response to sphingomyelin and cholesterol. J Biosci 2010; 35:583-93. [DOI: 10.1007/s12038-010-0067-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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Kao PH, Lin SR, Wu MJ, Chang LS. Membrane-bound conformation and phospholipid components modulate membrane-damaging activity of Taiwan cobra cardiotoxins. Toxicon 2009; 53:512-8. [DOI: 10.1016/j.toxicon.2009.01.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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23
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Xu W, Yi L, Feng Y, Chen L, Liu J. Structural insight into the activation mechanism of human pancreatic prophospholipase A2. J Biol Chem 2009; 284:16659-16666. [PMID: 19297324 DOI: 10.1074/jbc.m808029200] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Pancreatic phospholipase A2 (phospholipase A2 group 1B, G1B) belongs to the superfamily of secreted phospholipase A2 (PLA2) enzymes. G1B has been proposed to be a potential target for diseases such as hypertension, obesity, and diabetes. Human pancreatic prophospholipase A2 (pro-hG1B) is activated by cleavage of the first seven-residue propeptide (phospholipase A2 propeptide, PROP). However, questions still remain on the mode of action for pro-hG1B. In this work, we expressed pro-hG1B in Pichia pastoris and determined the crystal structure at 1.55-A resolution. The x-ray structure demonstrates that pro-hG1B forms a trimer. In addition, PROP occupies the catalytic cavity and can be self-cleaved at 37 degrees C. A new membrane-bound surface and activation mechanism are proposed based on the trimeric model of pro-hG1B. We also propose a new autoproteolytic mechanism for pro-hG1B by the reaction triad Asp49-Arg0-Ser(-2) that is similar to the serine protease catalytic triad.
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Affiliation(s)
- Wei Xu
- From the Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510663, China; Graduate University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lina Yi
- From the Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510663, China
| | - Yumei Feng
- From the Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510663, China
| | - Ling Chen
- From the Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510663, China; School of Life Sciences, University of Science and Technology of China, Hefei 230027, China.
| | - Jinsong Liu
- From the Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510663, China; School of Life Sciences, University of Science and Technology of China, Hefei 230027, China.
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24
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Kao PH, Wu MJ, Chang LS. Membrane-bound conformation of Naja nigricollis toxin gamma affects its membrane-damaging activity. Toxicon 2008; 53:342-8. [PMID: 19101582 DOI: 10.1016/j.toxicon.2008.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2008] [Revised: 11/02/2008] [Accepted: 12/03/2008] [Indexed: 11/25/2022]
Abstract
To address whether the conformational events associated with the absorption of Naja nigricollis toxin gamma on water-lipid interface plays a vital role in its membrane-damaging activity, the present study is carried out. Membrane-damaging activity of toxin gamma on 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC)/1, 2-dimyristoyl-phosphatidic acid (DMPA) vesicles was approximately 13-fold of that on 1, 2-dipalmitoyl-phosphatidylcholine (DPPC)/DMPA vesicles, while the binding affinity of toxin gamma for POPC/DMPA was twofold of that for DPPC/DMPA. Time-resolved fluorescence, acrylamide quenching and Fourier transform infrared spectra showed that POPC/DMPA-bound toxin gamma and DPPC/DMPA-bound toxin gamma did not adopt the same conformation. Moreover, geometrical arrangement of toxin gamma in contact with POPC/DMPA vesicles was different from that with DPPC/DMPA vesicles as evidenced by N-(fluorescein-5-thiocarbamoyl)-1,2-dihexadecanoyl-phosphatidylcholine fluorescence enhancement and cross-linking of membrane-bound toxin gamma. Taken together, our data show that different membrane packing densities arising from phospholipid acyl chain affect membrane-bound conformation of toxin gamma, thus changing its membrane-damaging activity.
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Affiliation(s)
- Pei-Hsiu Kao
- Institute of Biomedical Sciences, National Sun Yat-Sen University-Kaohsiung Medical University Joint Research Center, National Sun Yat-Sen University, No 70, Lien-Hai Road, Kaohsiung 804, Taiwan, ROC
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25
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26
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Chiou YL, Lin SR, Chang LS. Mutations onN-terminal region of Taiwan cobra phospholipase A2result in structurally distorted effects. J Pept Sci 2008; 14:890-7. [DOI: 10.1002/psc.1020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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27
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Chiou YL, Cheng YC, Kao PH, Wang JJ, Chang LS. Mutations on the N-terminal region abolish differentially the enzymatic activity, membrane-damaging activity and cytotoxicity of Taiwan cobra phospholipase A2. Toxicon 2008; 51:270-9. [DOI: 10.1016/j.toxicon.2007.10.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2007] [Revised: 09/27/2007] [Accepted: 10/02/2007] [Indexed: 12/01/2022]
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28
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Kao PH, Chen KC, Lin SR, Chang LS. The structural and functional contribution ofN-terminal region and His-47 on Taiwan cobra phospholipase A2. J Pept Sci 2008; 14:342-8. [DOI: 10.1002/psc.943] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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29
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Seres I, Fóris G, Varga Z, Kosztáczky B, Kassai A, Balogh Z, Fülöp P, Paragh G. The association between angiotensin II-induced free radical generation and membrane fluidity in neutrophils of patients with metabolic syndrome. J Membr Biol 2007; 214:91-8. [PMID: 17546512 DOI: 10.1007/s00232-006-0020-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Revised: 11/09/2006] [Indexed: 11/26/2022]
Abstract
Angiotensin II (Ang II) is able to induce free radical generation in neutrophils, which is more elevated in neutrophils of patients with hypercholesterolemia (HC). In addition, the signal processing through angiotensin I (Ang I) receptors is altered. In present study, we compared the Ang II-triggered free radical generation of neutrophils obtained from patients with relatively isolated forms of metabolic syndrome (MS) with membrane-bound cholesterol content and membrane fluidity. We determined the enhancement of Ang II-induced superoxide anion and leukotriene C(4) (LTC(4)) generation, membrane fluidity and cell-bound cholesterol content of neutrophils obtained from 12 control subjects, 11 patients with obesity (Ob), 10 patients with type 2 diabetes mellitus (t2-DM) and 12 patients with HC. The alteration of signal processing was studied after preincubation with different inhibiting drugs. Superoxide anion, LTC(4) production and membrane rigidity were increased in the following order: control < Ob < t2-DM < HC. Both Ang II-induced superoxide anion and LTC(4) generation were decreased in control cells by pertussis toxin and fluvastatin (Flu), whereas in each patient group, mepacrin, verapamil and Flu were effective, suggesting alterations in signal pathways, which may be attributed to isoprenylation. The enhancement of superoxide anion and LTC(4) generation correlated significantly with membrane rigidity, independently from the experimental groups and membrane-bound cholesterol content. Membrane rigidity of neutrophils, obtained from patients with MS, plays a role in Ang II-induced free radical generation independent of intracellular cholesterol homeostasis.
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Affiliation(s)
- Ildikó Seres
- First Department of Medicine, Medical and Health Science Center, University of Debrecen, Nagyerdei krt. 98, Debrecen, H-4012 Hungary
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30
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Tsai IH, Tsai HY, Saha A, Gomes A. Sequences, geographic variations and molecular phylogeny of venom phospholipases and threefinger toxins of eastern India Bungarus fasciatus and kinetic analyses of its Pro31 phospholipases A2. FEBS J 2006; 274:512-25. [PMID: 17166178 DOI: 10.1111/j.1742-4658.2006.05598.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Eight phospholipases A2 (PLAs) and four three-finger-toxins (3FTx) from the pooled venom of Bungarus fasciatus (Bf) were previously studied and sequenced, but their expression pattern in individual Bf venom and possible geographic variations remained to be investigated. We herein analyze the individual venom of two Bf specimens from Kolkata (designated as KBf) to address this question. Seven PLAs and five 3FTx were purified from the KBf venoms, and respective cDNAs were cloned from venom glands of one of the snakes. Comparison of their mass and N-terminal sequence revealed that all the PLAs were conserved in both KBf venoms, but that two of their 3FTx isoforms were variable. When comparing the sequences of these KBf-PLAs with those published, only one was found to be identical to that of Bf Vb-2, and the other five were 94-98% identical to those of Bf II, III, Va, VI and XI-2, respectively. Notably, the most abundant PLA isoforms of Bf and KBf venoms contain Pro31 substitution. They were found to have abnormally low k(cat) values but high affinity for Ca2+. Phylogenetic analysis based on the sequences of venom group IA PLAs showed a close relationship between Bungarus and Australian and marine Elapidae. As the five deduced sequences of KBf-3FTx are only 62-82% identical to the corresponding Bf-3FTx from the pooled venom, the 3FTx apparently have higher degree of individual and geographic variations than the PLAs. None of the KBf-3FTx was found to be neurotoxic or very lethal; phylogenetic analyses of the 3FTx also revealed the unique evolution of Bf as compared with other kraits.
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Affiliation(s)
- Inn-Ho Tsai
- Institute of Biological Chemistry, Academia Sinica, Taiwan.
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31
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Rouault M, Rash LD, Escoubas P, Boilard E, Bollinger J, Lomonte B, Maurin T, Guillaume C, Canaan S, Deregnaucourt C, Schrével J, Doglio A, Gutiérrez JM, Lazdunski M, Gelb MH, Lambeau G. Neurotoxicity and other pharmacological activities of the snake venom phospholipase A2 OS2: the N-terminal region is more important than enzymatic activity. Biochemistry 2006; 45:5800-16. [PMID: 16669624 PMCID: PMC2796912 DOI: 10.1021/bi060217r] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Several snake venom secreted phospholipases A2 (sPLA2s) including OS2 exert a variety of pharmacological effects ranging from central neurotoxicity to anti-HIV activity by mechanisms that are not yet fully understood. To conclusively address the role of enzymatic activity and map the key structural elements of OS2 responsible for its pharmacological properties, we have prepared single point OS2 mutants at the catalytic site and large chimeras between OS2 and OS1, a homologous but nontoxic sPLA2. Most importantly, we found that the enzymatic activity of the active site mutant H48Q is 500-fold lower than that of the wild-type protein, while central neurotoxicity is only 16-fold lower, providing convincing evidence that catalytic activity is at most a minor factor that determines central neurotoxicity. The chimera approach has identified the N-terminal region (residues 1-22) of OS2, but not the central one (residues 58-89), as crucial for both enzymatic activity and pharmacological effects. The C-terminal region of OS2 (residues 102-119) was found to be critical for enzymatic activity, but not for central neurotoxicity and anti-HIV activity, allowing us to further dissociate enzymatic activity and pharmacological effects. Finally, direct binding studies with the C-terminal chimera, which poorly binds to phospholipids while it is still neurotoxic, led to the identification of a subset of brain N-type receptors which may be directly involved in central neurotoxicity.
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Affiliation(s)
- Morgane Rouault
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS-UMR 6097, 660 route des Lucioles, Sophia Antipolis, 06560 Valbonne, France
| | - Lachlan D. Rash
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS-UMR 6097, 660 route des Lucioles, Sophia Antipolis, 06560 Valbonne, France
| | - Pierre Escoubas
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS-UMR 6097, 660 route des Lucioles, Sophia Antipolis, 06560 Valbonne, France
| | - Eric Boilard
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS-UMR 6097, 660 route des Lucioles, Sophia Antipolis, 06560 Valbonne, France
| | - James Bollinger
- Departments of Chemistry and Biochemistry, University of Washington, Seattle, Washington 98195, USA
| | - Bruno Lomonte
- Universidad de Costa Rica, Faculdad de Microbiologia, Instituto Clodomiro Picado, San José, Costa Rica
| | - Thomas Maurin
- Laboratoire de Virologie, IFR50, Faculté de Médecine, 06107 Nice cedex 2, France
| | - Carole Guillaume
- USM 0504, Biologie Fonctionnelle des Protozoaires, Laboratoire de Biologie Parasitaire, Museum National d’Histoire Naturelle, 61 rue Buffon, 75231 Paris cedex 05, France
| | - Stéphane Canaan
- Laboratoire d'Enzymologie Interfaciale et de Physiologie de la Lipolyse, CNRS-UPR 9025, 31 Chemin Joseph-Aiguier, 13402 Marseille cedex 20, France
| | - Christiane Deregnaucourt
- USM 0504, Biologie Fonctionnelle des Protozoaires, Laboratoire de Biologie Parasitaire, Museum National d’Histoire Naturelle, 61 rue Buffon, 75231 Paris cedex 05, France
| | - Joseph Schrével
- USM 0504, Biologie Fonctionnelle des Protozoaires, Laboratoire de Biologie Parasitaire, Museum National d’Histoire Naturelle, 61 rue Buffon, 75231 Paris cedex 05, France
| | - Alain Doglio
- Laboratoire de Virologie, IFR50, Faculté de Médecine, 06107 Nice cedex 2, France
| | - José María Gutiérrez
- Universidad de Costa Rica, Faculdad de Microbiologia, Instituto Clodomiro Picado, San José, Costa Rica
| | - Michel Lazdunski
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS-UMR 6097, 660 route des Lucioles, Sophia Antipolis, 06560 Valbonne, France
| | - Michael H. Gelb
- Departments of Chemistry and Biochemistry, University of Washington, Seattle, Washington 98195, USA
| | - Gérard Lambeau
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS-UMR 6097, 660 route des Lucioles, Sophia Antipolis, 06560 Valbonne, France
- Address correspondence to: Gérard Lambeau, Institut de Pharmacologie Moléculaire et Cellulaire, CNRS-UMR 6097, 660 route des Lucioles, Sophia Antipolis, 06560 Valbonne, France, Tel. +33 (0) 4 93 95 77 33; Fax. +33 (0) 4 93 95 77 08;
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