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Coagulation disorders are a primary symptom of envenomation caused by snakes belonging to the genus Bothrops. In the Northeast region of Brazil, the species Bothrops erythromelas and Bothrops leucurus are the main responsible for snakebite accidents. Due to the specific action of Bothrops venoms on several components of the coagulation cascade, the objective of this work was to characterize the coagulotoxic profile of B. erythromelas and B. leucurus venoms and the neutralizing potential of bothropic antivenom, considering that their venom are not used in the production of antivenom. Regarding the clotting components targeted by the venom of these species, B. leucurus samples had higher thrombin-like activity and ability to activate prothrombin, while the activation of Factor X was comparable between these two species. B.erythromelas and B. leucurus venom displayed α- and β-fibrinogenolytic activities, with the former presenting higher overall fibrinogenolytic activity. In contrast, B. erythromelas venom showed greater procoagulant activity on human plasma, assessed through the coagulation time induced by the venom samples and thromboelastometry. Bothropic antivenom inhibited the procoagulant potential of B. leucurus venom better than B. erythromelas. However, the ability of the antivenom to neutralize this activity is lower compared to that determined for the venom of B. jararaca, which is used for antivenom production. The results shown herein describe the procoagulant activity of B. leucurus and B. erythromelas venoms and highlight the differences regarding their procoagulant capacity on human plasma, contributing to a deeper understanding of the pathophysiology of the envenomation caused by these species., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier Ltd. All rights reserved.)

Rattlesnakes belonging to the genus Crotalus are widely distributed throughout the Americas. In Brazil, symptoms commonly associated with envenomation by Crotalus durissus collilineatus include myalgia, rhabdomyolysis, renal failure, neurotoxicity, and progressive paralysis, which are related to the protein composition of this venom. Snake venom composition exhibits compositional variability that may reflect geographic distribution, age, captivity, diet, sex, and even individual genetics. Although seasonality is also considered a possible source of variation, there are few reports of such variability in snake venom. In this work, venoms of the same eight C. durissus collilineatus were extracted every three months for two years, to analyze seasonal changes in composition and activities. To this end, venom composition was analyzed by protein quantification, SDS-PAGE, and HPLC, and the LAAO, PLA 2 and coagulant activities were measured. Venoms of these C. d. collilineatus showed minor seasonal differences in venom activities and no composition differences were found. LAAO and coagulant activities displayed a pattern of seasonal change, while PLA 2 activity seemed to have no seasonality tendency. Also, there are sexual differences, in which males seem to be more stable than females in regard to some activities. Individual variability occurs even in seasonal variation of activities, highlighting the importance of controlling circumstances of venom extraction before comparing results between groups of snakes., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Anita Mitico Tanaka Azevedo reports financial support was provided by State of Sao Paulo Research Foundation. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Snake venom protein synthesis undergoes finely regulated processes in the specialized secretory epithelium within the venom gland. Such processes occur within a defined period in the cell and at specific cellular locations. Thus, the determination of subcellular proteomes allows the characterization of protein groups for which the site may be relevant to their biological roles, thereby allowing the deconvolution of complex biological circuits into functional information. In this regard, we performed subcellular fractionation of proteins from B. jararaca venom gland, focusing on nuclear proteins since this cellular compartment comprises key effectors that shape gene expression. Our results provided a snapshot of B. jararaca's subcellular venom gland proteome and pointed to a 'conserved' proteome core among different life stages (newborn and adult) and between sexes (adult male and female). Overall, the top 15 highly abundant proteins identified in B. jararaca venom glands mirrored the panel of highly expressed genes in human salivary glands. Therefore, the expression profile observed for such a protein set could be considered a conserved core signature of salivary gland secretory epithelium. Moreover, the newborn venom gland displayed a unique expression signature of transcription factors involved in regulating transcription and biosynthetic processes and may mirror biological constraints of the ontogenetic development of B. jararaca, contributing to venom proteome diversity., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2023 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.)

Using approaches of transcriptomics and proteomics we have shown that the phenotype of Bothrops jararaca venom undergoes a significant rearrangement upon neonate to adult transition. Most regulatory processes in biology are intrinsically related to modifications of protein structure, function, and abundance. However, it is unclear to which extent intrinsic proteolysis affects toxins and snake venom phenotypes upon ontogenesis. Here we assessed the natural N-terminome of Bothrops jararaca newborn and adult venoms and explored the degree of N-terminal protein truncation in ontogenetic-based proteome variation. To this end we applied the Terminal Amine Isotopic Labeling of Substrates (TAILS) technology to characterize venom collected in the presence of proteinase inhibitors. We identified natural N-terminal sequences in the newborn (71) and adult (84) venoms, from which only 37 were common to both. However, truncated toxins were found in higher number in the newborn (212) than in the adult (140) venom. Moreover, sequences N-terminally blocked by pyroglutamic acid were identified in the newborn (55) and adult (49) venoms. Most toxin classes identified by their natural N-terminal sequences showed a similar number of unique peptides in the newborn and adult venoms, however, those of serine proteinases and C-type lectins were more abundant in the adult venom. Truncated sequences from at least ten toxin classes were detected, however the catalytic and cysteine-rich domains of metalloproteinases were the most prone to proteolysis, mainly in the newborn venom. Our results underscore the pervasiveness of truncations in most toxin classes and highlight variable post-translational events in newborn and adult venoms., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Species of Brachycephalus has been having taxonomical issues due its morphological similarity and genetic conservatism. Herein, we describe a new species of Brachycephalus from the south Mantiqueira mountain range and semidecidual forests in the municipalities of Mogi das Cruzes, Campinas and Jundiaí, state of São Paulo, Brazil, based on an integrative approach. It can be distinguished from all species of the B. ephippium species group based on morphological characters (especially osteology and head shape), advertisement call and divergence in partial mitochondrial DNA gene sequences (16S). The new species is genetically similar to B. margaritatus and morphologically similar to B. ephippium. It can be differentiated from B. ephippium by the presence of dark faded spots on skull and post-cranial plates, presence of black connective tissue connective tissue scattered over dorsal musculature, parotic plate morphology, smaller snout-vent length (adult SVL: males 13.46-15.92 mm; females 16.04-17.69 mm) and 3% genetic distance. We also present natural history data and discuss the robustness of the integrative approach, geographic distribution, genetic data, behaviour, fluorescence in ontogeny, and conservation status., Competing Interests: The authors have declared that no competing interests exist.

Maintenance of snakes at Butantan Institute started in the last century, intending to produce a different antivenom serum to reduce death caused by snakebites. Through a successful campaign coordinated by Vital Brazil, farmers sent venomous snakes to Butantan Institute by the railway lines with no cost. From 1908 to 1962, the snakes were kept in an outdoor serpentarium, where venom extraction was performed every 15 days. During this period, the snake average survival was 15 days. In 1963, the snakes were transferred to an adapted building, currently called Laboratory of Herpetology (LH), to be maintained in an intensive system. Although the periodicity of venom extraction remained the same, animal average survival increased to two months. With the severe serum crisis in 1983, the Ministry of Health financed remodeling for the three public antivenom producers, and with this support, the LH could be improved. Air conditioning and exhausting systems were installed in the rooms, besides the settlement of critical hygienic-sanitary managements to increase the welfare of snakes. In the early 1990s, snake survival was ten months. Over the years to the present day, several improvements have been made in the intensive serpentarium, as the establishment of two quarantines, feeding with thawed rodents, an interval of two months between venom extraction routines, and monitoring of snake health through laboratory tests. With these new protocols, average snake survival increased significantly, being eight years for the genus Bothrops , ten years for genus Crotalus and Lachesis, and four years for the genus Micrurus . Aiming the production of venoms of good quality, respect for good management practices is essential for the maintenance of snakes in captivity. New techniques and efficient management must always be sought to improve animal welfare, the quality of the venom produced, and the safety of those working directly with the venomous snakes., Competing Interests: Competing interests: The authors declare that they have no competing interests.

There are currently seven species of small frogs (up to 30 mm in snout-vent length) in the genus Paratelmatobius Lutz Carvalho 1958 (Frost, 2020). They are all endemic to mountain ranges in the Atlantic Forest, occurring in the Serra do Mar and Serra da Mantiqueira, southeastern Brazil (Santos et al. 2019). Most congeneric species are considered rare and their distribution is restricted to small areas (Domenico et al. 2014; Santos et al. 2020). Paratelmatobius mantiqueira Pombal Haddad 1999 is one of the most enigmatic species in the genus. It hadn't been seen from 1953, when the type series was collected, until 2005, when one specimen was found in the municipality of Resende, state of Rio de Janeiro (Vrcibradic et al. 2010). Recently, we found a new population of P. mantiqueira in the state of São Paulo. While reviewing the scattered information available about the species, we noticed inconsistencies related to the species' type locality. We propose its rectification in this manuscript.

Envenoming and deaths resulting from snakebites are a particularly important public health problem in rural tropical areas of Africa, Asia, Latin America, and New Guinea. In 2015, The Lancet highlighted snake-bite envenoming as a neglected tropical disease and urged the world to increase antivenom production. In Brazil, around 20,000 snakebites occur per year affecting mostly agricultural workers and children, of which 1% is caused by coral snakes (Micrurus sp.). Although human envenoming by coral snakes is relatively rare due to their semifossorial habits and nonaggressive behavior, they are always considered severe due to the neurotoxic, myotoxic, hemorrhagic, and cardiovascular actions of their venom, which is highly toxic when compared to the venom of other Brazilian venomous snakes as Bothrops sp. (pit vipers), Crotalus sp. (rattlesnakes), and Lachesis sp. (bushmasters). The production of antivenom serum is an important public health issue worldwide and the maintenance of venomous snakes in captivity essential to obtain high-quality venom. Though more than 30 species of Brazilian coral snakes exist, the specific antivenom serum produced with the venom of two species, Micrurus corallinus and M. frontalis, is able to neutralize the accidents caused by the genus in general. M. corallinus is considered a difficult species to maintain in captivity and concerned about this difficulty the Laboratory of Herpetology (LH) at Instituto Butantan, over the last 10 yr, has given special attention to its maintenance in captivity. In more than 20 yr of maintenance, LH has made some changes to improve Micrurus captive husbandry and welfare. The objective of this study was to verify the factors influencing the survival rates of coral snakes in captivity through data generated from 289 M. corallinus from the LH snake facility in the last 10 yr. We observed that survival rates increased significantly with the improvement of nutritional adequacy that included freezing food items before offering them to coral snakes, as well as the development of a new pasty diet to force-feed anorexic animals. Another important factor responsible for increasing life expectancy was the shift of the cage's substrate from Sphagnum to bark in 2010, aiding in the eradication of Blister Disease, which used to be responsible for the death of several coral snakes in previous years.

Objectives: The widespread dissemination of extended-spectrum β-lactamase-producing Enterobacteriaceae has become a major issue in veterinary medicine. However, until now, there has been no report of bacteria with such a phenotype in infected snakes. The aim of this study was to report the first draft genome sequence of an Enterobacter cloacae isolate (SERP1) recovered from a snake with infectious stomatitis., Methods: The whole genome of E. cloacae strain SERP1 was sequenced on an Illumina NextSeq platform and was de novo assembled using CLC NGS Cell v.10. Data analysis was performed using online tools from the Center of Genomic Epidemiology., Results: The genome size was calculated at 4966856bp, containing a total of 4796 protein-coding sequences. The strain was assigned to sequence type 279 (ST279) and, besides the clinically relevant bla CTX-M-15 and aac(6')-Ib-cr genes, it also presented resistance genes to β-lactams, aminoglycosides, phenicols, sulphonamides, tetracyclines, trimethoprim, quinolones and fosfomycin., Conclusion: These data offer novel information regarding multidrug-resistant E. cloacae dissemination in wild animals and might contribute to further comparative genomic analysis., (Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.)

Intraspecific venom variability has been extensively reported in a number of species and is documented to be the result of several factors. However, current evidence for snake venom variability related to captivity maintenance is controversial. Here we report a compositional and functional investigation of individual and pooled venoms from long-term captive (LTC) and recently wild-caught (RWC) B. jararaca snakes. The composition of individual venoms showed a remarkable variability in terms of relative abundance of toxins (evidenced by 1-DE and RP-HPLC), enzymatic activities (proteolytic, PLA 2 , and LAAO) and coagulant activity, even among captive specimens. Thus, no compositional and functional pattern could be established to assign each individual venom to a specific group. Conversely, pooled venom from LTC and RWC snakes showed no significant differences regarding protein composition (characterized by 1-DE and shotgun proteomics), enzymatic activities (proteolytic, PLA 2 and LAAO) and biological function (coagulant, hemorrhagic and lethal activities), except for edematogenic activity, which was more prominent in RWC venom pool. Additionally, both pooled venoms displayed similar immunoreactivity with the bothropic antivenom produced by Instituto Butantan. Taken together, our results highlight the complexity and the high intraspecific variation of B. jararaca venom, that is not influenced at a discernible extent by captivity maintenance., Biological Significance: Bothrops jararaca snakes are one of the main causes of snakebites in Southeastern Brazil. Due to its medical interest, the venom of this species is the most studied and characterized among Brazilian snakes and captive B. jararaca specimens are maintained for long periods of time in our venom production facility. However, knowledge on the influence of captivity maintenance on B. jararaca venom variability is scarce. In this report, we described a high compositional and functional variability of individual venoms from LTC and RWC B. jararaca snakes, which are not observed between LTC and RWC pooled venoms. This intraspecific variability is more likely to be due to genetic/populational differences rather than "captivity vs wild" conditions. In this regard, data generated by the present work support the use of venom from captive and wild snakes for antivenom production and scientific research. Moreover, the data generated by this study highlight the importance of analyzing individual venom samples in studies involving intraspecific venom variability., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Feeding specialization is a recurrent issue in the evolution of snakes and is sometimes associated to morphological and/or behavioral adaptations that improve snake performance to exploit a particular food type. Despite its importance for animal fitness, the role of physiological traits has been much less studied than morphological and behavioral traits in the evolution of feeding specialization in snakes. In this context, the energetic cost of post-prandial period is an important physiological factor due to the remarkable effect on the snake energy budget. We collected data on post-prandial metabolic rate (SDA) in five species of pit vipers from the genus Bothrops with different degrees of mammal feeding specialization to test the hypothesis that feeding specialist species have lower energy costs during the digestion of their regular food item when compared to species with a more generalist diet. Our results support this hypothesis and suggest that ontogenetic changes in diet can be accompanied by changes in energy cost of the digestion process.

The current proposal about the variation of standard metabolic rates (SMR) in snakes predicts that SMR is influenced by the feeding frequency (frequent or infrequent feeders). However, feeding frequency in snakes is poorly studied and hard to quantify under natural conditions. Alternatively, foraging strategy was studied for a large number of species and is usually related to the feeding frequency. In this work, we performed a meta-analysis on the SMR of compiled data from 74 species of snakes obtained from the literature and five more different species of lanceheads (genus Bothrops), after categorization according to the foraging mode (ambush or active foraging) and regarding their phylogenetic history. We tested the hypothesis that foraging mode (FM) is a determinant factor on the interspecific variation of SMR despite the phylogenetic relationship among species. We demonstrated that FM predicted SMR, but there is also a partial phylogenetic structuration of SMR in snakes. We also detected that evolution rates of SMR in active foragers seem to be higher than ambush-hunting snakes. We suggested that foraging mode has a major effect over the evolution of SMR in snakes, which could represent an ecophysiological co-adaptation, since ambush hunters (with low feeding rates) present a lower maintenance energetic cost (SMR) when compared to active foragers. The higher SMR evolution rates for active foraging snakes could be related to a higher heterogeny in the degree of activity during hunting by active foragers when compared to ambush-hunting snakes.

We carried out an analysis of the venom gland proteome of Bothrops jararaca taking into account two distinct phases of its ontogenetic development (i.e., newborn and adult) and the marked sexual dimorphism recently reported on its venom proteome. Proteomic data analysis showed a dynamic rearrangement in the proteome landscape of B. jararaca venom gland upon development and gender-related changes. Differentially expressed proteins covered a number of biological pathways related to protein synthesis, including proteins associated with transcription and translation, which were found to be significantly higher expressed in the newborn venom gland. Our results suggest that the variation in the expression levels of cellular proteins might give rise to an even higher variation in the levels of the expressed toxins. Upon aging, the venom gland proteome repertoire related to the protein synthesis together with ecological traits would have an impact on the toxin repertoire, which, in the case of B. jararaca species, would enable the species to deal with different prey types during its lifespan. Proteomic data are available via ProteomeXchange with identifier PXD004186.

The pharmacological activities displayed by Bothrops jararaca venom undergo a significant ontogenetic shift. Similarly, the diet of this species changes from ectothermic prey in early life to endothermic prey in adulthood. In this study we used large and representative newborn and adult venom samples consisting of pools from 694 and 110 specimens, respectively, and demonstrate a significant ontogenetic shift in the venom proteome complexity of B. jararaca. 2-DE coupled to MS protein identification showed a clear rearrangement of the toxin arsenal both in terms of the total proteome, as of the glycoproteome. N-glycosylation seems to play a key role in venom protein variability between newborn and adult specimens. Upon the snake development, the subproteome of metalloproteinases undergoes a shift from a P-III-rich to a P-I-rich profile while the serine proteinase profile does not vary significantly. We also used isobaric tag labeling (iTRAQ) of venom tryptic peptides for the first time to examine the quantitative changes in the venom toxins of B. jararaca upon neonate to adult transition. The iTRAQ analysis showed changes in various toxin classes, especially the proteinases. Our study expands the in-depth understanding of venom complexity variation particularly with regard to toxin families that have been associated with envenomation pathogenesis., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)