Venomics across the Bothrops neuwiedi Species Complex Revealed a P-III Snake Venom Metalloproteases/K49-PLA2 Dichotomy and a Remarkable Paraspecific Neutralization of the Brazilian Pentabothropic Antivenom.

Snakes of the Bothrops neuwiedi complex are widely distributed and represent medically important species in Brazil. Here, we report compositional and functional profiles of the venom of seven species of Bothrops neuwiedi group: Bothrops mattogrossensis, Bothrops pauloensis, Bothrops pubescens, Bothrops diporus, Bothrops neuwiedi, Bothrops marmoratus, and Bothrops erythromelas. Toxin composition of individual and pooled venoms showed remarkable inter- and intraspecific variability of the relative abundance of toxins (evidenced by SDS-PAGE and RP-HPLC) and enzymatic activities (proteolytic, PLA2, and thrombin-like activities). In vivo analyses showed that B. erythromelas venom is the most hemorrhagic, B. diporus was the most lethal, and B. pubescens showed the highest myotoxic activity. Histopathological analysis showed that all venoms induced edema, hemorrhage, inflammatory infiltrate, and necrosis of muscle fibers. Consistent with large research evidence on the paraspecificity of various commercial antivenoms generated in Latin America, the pentabothropic antivenom produced by Instituto Butantan showed a high profile of immunoreactivity and lethality neutralization capability toward the venoms of the seven species of the B. neuwiedi clade. Interpreted through the prism of evolution, our data revealed a PIII-SVMP/K49-PLA2 compositional dichotomy and a remarkable conservation of immunological cross-reactivity across congeneric venoms throughout the 12-16 million years of Bothrops phylogeny.