Bothrops ayerbei, a pitviper inhabiting the Pat铆a River's basin (Valle Alto del R铆o Pat铆a) in the Southwestern Department of Cauca, Colombia, was considered as a variant form of
Bothrops asper prior to being proposed as a new species in 2010, on the basis of subtle morphological differences. This study reports the proteomic and functional profiling of
B. ayerbei venom. Its most striking feature is an almost complete absence (0.7%) of phospholipases A
2 (PLA
2), which is in contrast to the high proportion of these enzymes (25.3%) in the venom of
B. asper from Cauca, as well as in other species of
Bothrops. The predominant proteins in
B. ayerbei venom are metalloproteinases (53.7%), in agreement with its higher hemorrhagic and lethal activities compared to
B. asper venom. Moreover, the negligible content of PLA
2s in
B. ayerbei venom correlates with its weaker myotoxic effect, in contrast to
B. asper venom, here shown to contain abundant Asp49- and Lys49-type PLA
2s responsible for its strong myotoxic activity. Other components identified in
B. ayerbei venom include bradykinin-potentiating-like peptides and proteins belonging to the C-type lectin/lectin-like, serine proteinase, l-amino acid oxidase, disintegrin, cysteine-rich secretory protein, nerve growth factor, and phosphodiesterase families. The venom composition of
B. ayerbei resembles that of neonate specimens of
B. asper, which shows a predominance of metalloproteinases, with only low amounts of PLA
2s. Therefore, the present findings suggest that the expression of venom proteins in
B. ayerbei, in contrast to
B. asper, might retain a marked 鈥榩aedomorphic鈥?condition. Altogether, the proteomic and toxicological characterization of the venom of
B. ayerbei here reported argues in favor of its taxonomical separation from
B. asper in Cauca, Colombia.
Biological significance
B. ayerbei, a pitviper found in Cauca, Colombia, had been considered as a variant form of B. asper, but was recently described as a new species on the basis of subtle morphological differences. Our study provides the first detailed proteomic and functional analysis of the venom of B. ayerbei, revealing striking interspecific variation from B. asper, thus arguing in favor of their taxonomical separation. In addition, the observed composition of the venom of B. ayerbei correlates well with its functional and toxicological properties, helping to predict the main clinical manifestations in envenomings by this species, which inflicts a considerable number of snakebites in the Southwestern regions of Colombia.
