Differences in snake venom composition occur across all taxonomic levels and it has been argued that this variation represents an adaptation that has evolved to facilitate the capture and digestion of prey and evasion of predators. is a terrestrial pitviper that is distributed across the Amazon region, where it occupies different habitats. Using statistical analyses and functional assays that incorporate individual variation, we analyzed the individual venom variability in snakes from four different habitats (forest, pasture, degraded area, and floodplain) in and around the Amazon River in Brazil.
View Article and Find Full Text PDFVariability in snake venom composition has been frequently reported and correlated to the adaptability of snakes to environmental conditions. Previous studies report plasticity for the venom phenotype. However, these observations are not conclusive, as the results were based on pooled venoms, which present high individual variability.
View Article and Find Full Text PDFVariability in the composition of snake venoms occurs in different taxa and is usually correlated to snake fitness. Here, we compared B. atrox venoms from three different geographic regions across the Brazilian Amazon and found remarkable functional differences particularly between venoms from two populations separated by the Amazon River, in specimens born, raised and maintained under the same conditions at Instituto Butantan serpentary.
View Article and Find Full Text PDFUnlabelled: Elucidating the molecular mechanisms underlying snake venom variability provides important clues for understanding how the biological functions of this powerful toxic arsenal evolve. We analyzed in detail individual transcripts and venom protein isoforms produced by five specimens of a venomous snake (Bothrops atrox) from two nearby but genetically distinct populations from the Brazilian Amazon rainforest which show functional similarities in venom properties. Individual variation was observed among the venoms of these specimens, but the overall abundance of each general toxin family was conserved both in transcript and in venom protein levels.
View Article and Find Full Text PDFUnlabelled: Many scorpion accidents occur in the Brazilian Amazonian region and are frequently caused by Tityus obscurus. Approximately 5% of the crude venom of this species is composed of short linear, non-disulfide-bridged peptides, which have not been intensively investigated. As a consequence, only a few of these peptides have been structurally and functionally characterized to date.
View Article and Find Full Text PDFUnlabelled: Venom variability is commonly reported for venomous snakes including Bothrops atrox. Here, we compared the composition of venoms from B. atrox snakes collected at Amazonian conserved habitats (terra-firme upland forest and várzea) and human modified areas (pasture and degraded areas).
View Article and Find Full Text PDFThere are a great number of studies about Brazilian scorpions. However, little is known about the venom of scorpions of northern Brazil, mainly about Tityus obscurus, which is responsible for the most number of accidents in the Amazon. Thus, this study aimed to evaluate some pharmacological effects of T.
View Article and Find Full Text PDFJ Venom Anim Toxins Incl Trop Dis
February 2014
Background: Scorpion envenomations are a major public health problem in Brazil, whose most dangerous cases are attributable to the genus Tityus. This study was designed to compare the clinical and demographic features of envenomations by Tityus obscurus in two areas of the state of Pará located in the Amazon basin.Were compared demographic findings, local and systemic signs and symptoms of human envenomations caused by T.
View Article and Find Full Text PDFIn Latin America, Bothrops snakes account for most snake bites in humans, and the recommended treatment is administration of multispecific Bothrops antivenom (SAB--soro antibotrópico). However, Bothrops snakes are very diverse with regard to their venom composition, which raises the issue of which venoms should be used as immunizing antigens for the production of pan-specific Bothrops antivenoms. In this study, we simultaneously compared the composition and reactivity with SAB of venoms collected from six species of snakes, distributed in pairs from three distinct phylogenetic clades: Bothrops, Bothropoides and Rhinocerophis.
View Article and Find Full Text PDFWe describe two geographically differentiated venom phenotypes across the wide distribution range of Bothrops atrox, from the Colombian Magdalena Medio Valley through Puerto Ayacucho and El Paují, in the Venezuelan States of Amazonas and Orinoquia, respectively, and São Bento in the Brazilian State of Maranhão. Colombian and Venezuelan venoms show an ontogenetic toxin profile phenotype whereas Brazilian venoms exhibit paedomorphic phenotypes. Venoms from each of the 16 localities sampled contain both population-specific toxins and proteins shared by neighboring B.
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