Electrophoretic Characterization of Venom Proteins of <em>Montivipera xanthina</em> (Gray, 1849) (Ophidia: Viperidae)

Abstract

In this study, with the aim of evaluating coagulant activities in the venom of Mo ntivipera xanthina, we analyzed venom proteins, digestion patterns of fibrinogen chains incubated with venom, and the effects of protease inhibitors on M. xanthina venom proteases. Venom samples were obtained from four adult specimens collected in Gümüldür (Izmir, Turkey). SDS-PAGE analysis showed the presence of 17 protein bands or band groups in the molecular mass range of 20 to 200 kDa. The specific digestion patterns of fibrinogen chains revealed that M. xanthina venom possesses fibrinogenolytic enzymes, which could be involved in coagulation processes during envenomation. Fibrinogenolytic activity affected the Aα-chain and showed a time-dependent effect on Bβ-chains, which suggests the presence of both metalloproteinases and serine proteases in M. xanthina venom. After observing the fibrinogenolytic activity of M. xanthina venom, further research should focus on the isolation, identification, and characterization of individual venom components in order to provide insight into their function and biological roles.

Determination of the fibrinogenolytic activity of Montivipera raddei (Raddeʼs mountain viper) venom

“…Additional bands observed after venom treatment (at about 43, 23, 20, 16 kDa below the γ chain band) are likely due to the cleavage of the Aα chain, and this result suggests the presence of multiple cleavage sites. Similar effects on fibrinogen were also reported for other viperid venoms and as well as the venoms of other groups [12,29].…”

“…Comparing the results of the present study with this paper, it can be concluded that both M. raddei and M. xanthina venoms predominantly contain α-fibrinogenases and possibly βfibrinogenolytic enzymes with much lower activities. The major fibrinogenolytic enzyme group of M. raddei venom was clearly shown to be a metalloproteinase in the present study, exhibiting strong inhibition of activity by EDTA and 1,10-phenanthroline, whereas this inhibition by M. xanthina venom was not significant, albeit maintaining a possible partial inhibition [29]. The venom of M. xanthina did not cause observable degradation of the Aα chain after 10 min of incubation [29] while our results showed that M. raddei venom started to degrade the Aα chain at the same incubation time, suggesting that the fibrinogenolytic activity of M. raddei venom is slightly stronger than that of M. xanthina.…”

“…This result raises the possibility of at least partial inhibition of the fibrinogenolytic activity in the venom by EDTA. It was also reported that this activity was partially inhibited in the presence of a protease inhibitor cocktail containing serine, cysteine and metalloprotein inhibitors [29].…”

“…The fibrinogenolytic activity of Montivipera xanthina, a closely related species to M. raddei, was assessed by tricine SDS-PAGE in a previous study, with the results indicating that M. xanthina venom contained fibrinogenolytic enzymes that mainly cleaved the Aα chain of fibrinogen [29]. Although the SDS-PAGE results were not as clear as those obtained for the Aα chain, the authors stated that M. xanthina venom also contained β-fibrinogenase.…”

Comparative compositional and functional venomic profiles among venom specimens from juvenile, subadult and adult Russell’s viper ( Daboia siamensis ): correlation with renal pathophysiology in experimental rabbits

“…However, the rationale for the observed ontogenetic changes remains obscure, as little is known about the different pathophysiological changes in renal functions after envenomation with D. siamensis and the differences in the protein abundance of its venom. The mechanisms of venom action within the body to induce AKI during envenomation from D. siamensis have not been determined, although several studies in other snake species have reported ontogenetic differences among venoms of the same species, including variations in the biological and biochemical features [4,5,6] differences in venom compositions [7,8,9,10,11], toxicity [4,12,13,14] and enzymatic activity [8,14]. The abundance of different toxic and non-toxic proteins in snake venom are influenced by many factors, including variations in taxonomy, age, sex, geography, diet and seasons [15,16,17].…”