32 research outputs found

    Proteomic Characterization of the Hyaluronidase (EC 3.2.1.35) from the Venom of the Social Wasp Polybia paulista

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    Polybia paulista wasp venom possesses three major allergens: phospholipase A(1), hyaluronidase and antigen-5. To the best of our knowledge, no hyaluronidase from the venom of Neotropical social wasps was structurally characterized up to this moment, mainly due to its reduced amount in the venom of the tropical wasp species (about 0.5% of crude venom). Four different glycoproteic forms of this enzyme were detected in the venom of the wasp Polybia paulista. In the present investigation, an innovative experimental approach was developed combining 2-D SDS-PAGE with in-gel protein digestion by different proteolytic enzymes, followed by mass spectrometry analysis under collision-induced dissociation CID) conditions for the complete assignment of the protein sequencing. Thus, the most abundant form of this enzyme in P. paulista venom, the hyaluronidase-III, was sequenced, revealing that the first 47 amino acid residues from the N-terminal region, common to other Hymenoptera venom hyaluronidases, are missing. The molecular modeling revealed that hyaluronidase-III has a single polypeptide chain, folded into a tertiary structure, presenting a central (beta/alpha)(5) core with alternation of beta-strands and alpha-helices; the tertiary structure stabilized by a single disulfide bridge between the residues Cys(189) and Cys(201). The structural pattern reported for P. paulista venom hyaluronidase-III is compatible with the classification of the enzyme as member of the family 56 of glycosidase hydrolases. Moreover, its structural characterization will encourage the use of this protein as a model for future development of component-resolved diagnosis.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Using Proteomic Strategies for Sequencing and Post-Translational Modifications Assignment of Antigen-5, a Major Allergen from the Venom of the Social Wasp Polybia paulista

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    Antigen-5 is one of the major allergens identified in wasp venoms, and despite the fact that its biological function is still unknown, many studies have demonstrated its allergenicity. In this study, the biochemical and structural characterization of antigen-5 from the venom of the social wasp Polybia paulista are reported. A gel-based mass spectrometry strategy with CID fragmentation methods and classical protocols of protein chemistry, which included N- and C-terminal sequencing, were used to assign the complete sequence and determine the presence/location of the post-translational modifications (PTMs) of this protein. Six different isoforms of antigen-5 were identified in the crude venom of P. paulista; the most abundant, which corresponds to the intact form of this protein, was recognized by the pool of human specific-IgE. This protein was extensively sequenced through CID mass spectrometry, and a series of PTMs were observed such as hydroxylation, phosphorylation, and glycosylation. Sequence data revealed that this protein has 59.3-93.7% identity with antigen-5 proteins from other known vespid venoms. The molecular model of P. paulista antigen-5 shows that this protein has three alpha-helices, one 3(10), helix, and four beta-sheets covering 28 and 17.9% of the sequence, respectively. The identification and characterization of allergenic compounds is essential for the development of advanced component-resolved allergy diagnostics and treatment.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Proteomic characterization of the multiple forms of the PLAs from the venom of the social wasp Polybia paulista

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    The phospholipases A(1) (PLA(1)s) from the venom of the social wasp Polybia paulista occur as a mixture of different molecular forms. To characterize the molecular origin of these structural differences, an experimental strategy was planned combining the isolation of the pool of PLAs from the wasp venom with proteomic approaches by using 2-D, MALDI-TOF-TOF MS and classical protocols of protein chemistry, which included N- and C-terminal sequencing. The existence of an intact form of PLA(1) and seven truncated forms was identified, apparently originating from controlled proteolysis of the intact protein; in addition to this, four of these truncated forms also presented carbohydrates attached to their molecules. Some of these forms are immunoreactive to specific-IgE, while others are not. These observations permit to raise the hypothesis that naturally occurring proteolysis of PLA(1), combined with protein glycosylation may create a series of different molecular forms of these proteins, with different levels of allergenicity. Two forms of PLA(2)s, apparently related to each other, were also identified; however, it was not possible to determine the molecular origin of the differences between both forms, except that one of them was glycosylated. None of these forms were immunoreactive to human specific IgE.FAPESP[05/00982-1]BIOprospecTA/FAPESP[06/57122-7]CNPqCAPE

    Proteomic profiling of the molecular targets of interactions of the mastoparan peptide Protopolybia MP-III at the level of endosomal membranes from rat mast cells

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    It is well known that the activation of mast cells due to the binding of mastoparan to the Ga subunit of trimeric G proteins involves exocytosis regulation. However, experimental evidence in the literature indicates that mastoparan can also activate certain regulatory targets of exocytosis at the level of the mast cell endosomal membranes that have not yet been identified. Therefore, the aim of the present investigation was the proteomic identification of these targets. To achieve these objectives, mast cells were activated by the peptide Protopolybia MP-III, and the proteins of the endosomal membranes were converted to proteoliposomes using sonication. Proteins were separated from one another by affinity chromatography using proteoliposomes as analytes and Protopolybia MP III-immobilized Sepharose 4B resin as the ligand. This experimental approach, which used SDS-PAGE, in-gel trypsin digestion and proteomic analysis, permitted the identification of five endosomal proteins: Rho GTPase Cdc 42 and exocyst complex component 7 as components of the Ca2+-independent FceRI-mediated exocytosis pathway, synaptosomal-associated protein 29, and GTP-binding protein Rab3D as components of the Ca2+-dependent FceRI-mediated exocytosis pathway and Ras-related protein M-Ras, a protein that is related to the mediation of cell shaping and proliferation following exocytosis. The identification of the five proteins as targets of mastoparans may contribute in the near future to the use of this family of peptides as novel tools for dissecting the mechanism of exocytosis in mast cells.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Multiobjective optimization for vibration reduction in composite plate structures using constrained layer damping

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    This paper presents a multiobjective optimization approach to minimize weight and maximize modal damping in laminated composite panels with Constrained Layer Damping (CLD) treatments. The design variables are the number and position of the CLD patch treatments on the surface of the laminated plate. The Direct MultiSearch (DMS) solver for multiobjective optimization problems is used in this work. DMS is a solver which does not use any derivatives of the objective functions. A previously developed finite element model for sandwich plates with viscoelastic core and anisotropic laminated face layers is adapted to model the plate with the CLD treatments. Applications for L-shaped and T-shaped plates are presented and both trade-off Pareto optimal fronts and the respective treatment configurations are obtained and the results are analyzed and discussed.info:eu-repo/semantics/publishedVersio

    Revisiting Polybia paulista wasp venom using shotgun proteomics - Insights into the N-linked glycosylated venom proteins

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    The partial proteome of Polybia paulista wasp venom was previously reported elsewhere using a gel-dependent approach and resulted in the identification of a limited number of venom toxins. Here, we reinvestigated the P. paulista venom using a gel-free shotgun proteomic approach; the highly dynamic range of this approach facilitated the detection and identification of 1673 proteins, of which 23 venom proteins presented N-linked glycosylation as a posttranslational modification. Three different molecular forms of PLAT were identified as allergenic proteins, and two of these forms were modified by N-linked glycosylation. This study reveals an extensive repertoire of hitherto undescribed proteins that were classified into the following six different functional groups: (i) typical venom proteins; (ii) proteins related to the folding/conformation and PTMs of toxins; (iii) proteins that protect toxins from oxidative stress; (iv) proteins involved in chemical communication; (v) housekeeping proteins; and (vi) uncharacterized proteins. It was possible to identify venom toxin-like proteins that are commonly reported in other animal venoms, including arthropods such as spiders and scorpions. Thus, the findings reported here may contribute to improving our understanding of the composition of P. paulista venom, its envenoming mechanism and the pathologies experienced by the victim after the wasp stinging accident. Biological significance: The present study significantly expanded the number of proteins identified in P. paulista venom, contributing to improvements in our understanding of the envenoming mechanism produced by sting accidents caused by this wasp. For example, novel wasp venom neurotoxins have been identified, but no studies have assessed the presence of this type of toxin in social wasp venoms. In addition, 23 N-linked glycosylated venom proteins were identified in the P. paulista venom proteome, and some of these proteins might be relevant allergens that are immunoreactive to human IgE2006073CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP301656/2013-4; 150699/2017-42013/26451-9; 2016/16212-5; 2017/04680-7; 2017/10373-0; 2017/22405-

    A simple, rapid method for the extraction of whole fire ant venom (Insecta: Formicidae: Solenopsis)

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    The invasive fire ant Solenopsis invicta is medically important because its venom is highly potent. However, almost nothing is known about fire ant venom proteins because obtaining even milligram-amounts of these proteins has been prohibitively challenging. We present a simple and fast method of obtaining whole venom compounds from large quantities of fire ants. For this, we separate the ants are from the nest soil, immerse them in dual-phase mixture of apolar organic solvent and water, and evaporate each solvent phase in separate. The remaining extract from the aqueous phase is largely made up of ant venom proteins. We confirmed this by using 2D gel electrophoresis while also demonstrating that our new approach yields the same proteins obtained by other authors using less efficient traditional methods. © 2013 Elsevier Ltd

    Molecular cloning, expression and IgE-immunoreactivity of phospholipase A1, a major allergen from Polybia paulista (hymenoptera: vespidae) venom

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Polybia paulista (Hymenoptera: Vespidae) is a clinically relevant social wasp that frequently causes stinging accidents in southeast Brazil. To date, diagnosis and specific immunotherapy (SIT) of allergy are based on the use of crude venom extracts. Produ1244452FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)2006/54799-6; 2014/13936- 7; 2009/51539-101197/ 10-DF
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