Project description:Coral snakes represent a highly diversified group of elapids in the New World. However, little is known about the diversity of coral snakes in the state of Bahia, making it essential to map their distribution and gain a better understanding of the variability in their venoms. Such knowledge is crucial not only for evolutionary and ecological studies but also for improving antivenom production and the clinical management of envenomations caused by these snakes. The MS data demonstrated in this study, the variation in the composition and activities of Micrurus venoms from the state of Bahia, Brazil, evidencing their diversity. Analysis through proteomic and functional studies of three different venom samples reveals differences in protein composition, which correlate with biological and enzymatic activities, as well as varying lethal potencies.
Project description:Functional and Evolutionary Insights into the Intergenic Deletion n.28271delA in SARS-CoV-2: Implications for Genomic Surveillance and Public Health
Project description:Venoms are important evolutionary keys and innovation for several animal taxons., including snakes. Their use is specially related to feed, predation and defense. Snake venoms are composed mainly by free secreted proteins, about 98%, and stored in the lumen of the venom gland, where they are processed through poorly understood mechanisms. In the perspective of protein-diversity, venoms undergo evolutionary pressure which generate a rapid evolutionary response, causing a great diversity in their toxin-components. We know now that extracellular vesicles exist in snake venom, although their biological role are still unknown. We believe that understanding EV-mediated effects could change our way of seeing envenoming, especially long-term sequelae. From what we know about EVs and snake venoms, there is a lot of potential of cross-organism communication occurrence between snakes and human victims. To advance in the comprehension of venom EVs function, we used fresh B. jararaca venom as our model. Fresh venom was fractionated by sequential centrifugation, resulting in two populations of vesicles (Bj-EVs). Purified Bj-EVs were analyzed by electron microscopy, NTA and proteomics. The interaction of Bj-EVs with mammalian cells was accessed by fluorescence and electron microscopy.
Project description:We report the perturbational effects of 25 crude venoms on human IMR-32 (neuroblastoma) cells. These data are used to evaluate the VenomSeq transcriptomic data analysis workflow, and to provide the first dataset generated by this workflow. By comparison with data published by the Connectivity Map team, and other free sources of genetic perturbation in the context of disease or drug exposure, we use these data to discover several novel associations between venoms and specific therapeutic actions.
Project description:Background The phenotypic polymorphism in rattlesnake venoms has been thoroughly documented, showing a dichotomy between haemorrhagic (Type I) and neurotoxic (Type II) venoms. In South America, the Type II phenotype is predominant; however, evidence exists of Type I haemorrhagic venoms in C. d. ruruima, raising questions about the efficacy of the Crotalus antivenom prepared for the Type II phenotype in treating Crotalus Type I snakebite patients, for whom the administration of Bothrops-Crotalus antivenom has been proposed. Methodology/Principal Findings This study characterises the dichotomy of C. d. ruruima venom based on the structure of isoforms differentially expressed in Type I and Type II venoms, the biological activities of each phenotype, and the implications for the clinical management of snakebites in Northern Brazil. Four toxins were differentially expressed in Type I and Type II venoms: two PIII-class SVMPs, which were highly expressed in Type I venoms and associated with proteolytic and haemorrhagic activity, and two PLA2s, corresponding to Crotoxin A and B chains, identified in Type II venoms and associated with increased phospholipase A2, myotoxic activities, and heightened lethality. The structure of Crotoxin chains was well conserved compared to C. d. terrificus crotoxin. However, compared to Bothropasin, the SVMP sequences exhibited several substitutions in functional and immunoreactive regions, resulting in low haemorrhagic activity and slight reactivity/neutralisation by Bothrops antivenom. In opposition, Crotalus antivenom reacted with high antibody titres and neutralised all activities of both venom subtypes, except the low haemorrhagic activity induced by Type I venoms. Conclusions/Significance The efficacy of Bothrops antivenom in incidents involving snakes of the Type I phenotype remains uncertain, and we advocate for an urgent prospective study in Roraima to assess the outcomes and benefits for patients receiving either Bothrops-Crotalus or solely Crotalus antivenoms following rattlesnake bites. Meanwhile, administering Bothrops-Crotalus antivenom could be warranted. However, it is crucial to remain aware of the issues of injecting heterologous Bothrops antibodies with limited efficacy in treating Crotalus snakebite patients.