Individual venom profiling of Crotalus durissus terrificus specimens from a geographically limited region: Crotamine assessment and captivity evaluation on the biological activities

Abstract

Crotalus durissus terrificus (Cdt) venom major components comprise crotoxin, crotamine, gyroxin and convulxin. Crotamine exerts a myotoxic action, among others, but its expression varies even amid snakes from the same region. Biochemical, enzymatic and pharmacological variations of venoms may be associated with the geography, climate, gender, age, and diet, as well as captivity time and venom extraction intervals. The present study aimed to characterize the Cdt venom from the Botucatu region, (SP, Brazil), by assessing its biochemical, pharmacological and enzymatic properties. Venoms from newly captured snakes and already-captured animals were characterized comparatively to verify the sexual, environmental (length of captivity) and ontogenetic variations that could influence the venom composition. Protein concentration, SDS-PAGE and RP-HPLC were performed and the coagulant, toxic (LD50) and crotamine activities were assayed. Individual SDS-PAGE analyses (315 samples) were performed and the biological activities of the venom of 60 adults (captive and newly captured males and females) and 18 newborns were compared with the Brazilian Reference Venom. Crotamine was found in 39.7% (125/315) of the samples, as determined by SDS-PAGE and RP-HPLC. Protein concentration differed significantly between adults (75%) and newborns (60%). RP-HPLC and SDS-PAGE analyses showed highly variable protein concentration and copious crotoxin isoforms; however, the LD50 values decreased during the captivity time. Cdt venom biological activities were similar among adult groups, but diminished during the captivity period. The current findings demonstrate that venoms vary significantly in terms activity and protein concentration, despite originating from the same specie and region.

Crotamine in Crotalus durissus: distribution according to subspecies and geographic origin, in captivity or nature

“…Among these venom samples, 131 were crotaminenegative, corresponding to 62% of the total samples analyzed. A comparable result was obtained by Lourenço et al [51], but this majority of crotamine-negative snakes could be due to the higher number of samples of some specific geographic region or subspecies.…”

Antivenomics as a tool to improve the neutralizing capacity of the crotalic antivenom: a study with crotamine

“…For example, crotoxin, a neurotoxic phospholipase A 2 (PLA 2 ), is the main toxin of C. durissus venom and accounts for 70–90% of its venom proteome [6–10]. On the other hand, significant variation has been observed for crotamine at both individual and population levels, since it accounts from 2 up to 22% of C. durissus proteome [9, 11–13]. There is also a positive correlation between the concentration of crotamine present in venom and the level of crotamine gene expression (ranging from 1 to 32 copies per haploid genome) [12].…”

EVALUATION OF THE ANTIBACTERIAL ACTIVITY OF Crotalus durissus terrificus CRUDE VENOM

“…Variations in venom composition, even among snakes from the same species, have already been reported and are probably influenced by factors such as diet and geographic distribution (34,35) , which has been demonstrated in some studies evaluating C. d. terrificus (36,48) . The effect of the crude venom of C. adamanteus from the Crotalus genus was evaluated by using the disc-diffusion method and was also thought inhibit the growth of S. aureus, Proteus vulgaris, and Proteus mirabilis, but did no exert activity against P. aeruginosa (27) , which was different from the results of our study of these bacteria.…”