Venomics and Peptidomics of Palearctic vipers: Clade-wide analysis of seven taxa of the generaVipera,Montivipera,MacroviperaandDaboiaacross Türkiye

Abstract

Snake venom variations are a crucial factor to understand the consequences of snakebite envenoming worldwide and therefore it's important to know about toxin composition alterations between taxa. Palearctic vipers of the generaVipera,Montivipera,MacroviperaandDaboiahave high medical impacts across the Old World. One hotspot for their occurrence and diversity is Türkiye on the border between the continents, but many of their venoms remain still understudied. Here, we present the venom compositions of seven Turkish viper taxa. By complementary mass spectrometry-based bottom-up and top-down workflows, the venom profiles were investigated on proteomics and peptidomics level. This study includes the first venom descriptions ofVipera berus barani,Vipera darevskii,Montivipera bulgardaghica albizonaandMontivipera xanthina, as well as first snake venomics profiles of TurkishMacrovipera lebetinus obtusaandDaboia palaestinae, including an in-depth reanalysis ofMontivipera bulgardaghica bulgardaghicavenom. Additionally, we identified the modular consensus sequence pEXW(PZ)1-2P(EI)/(KV)PPLE for bradykinin-potentiating peptides (BPP) in viper venoms. For better insights into variations and potential impacts of medical significance the venoms were compared against other Palearctic viper proteomes, including the first genus-wideMontiviperavenom comparison. This will help the risk assessment of snakebite envenoming by these vipers and aid in predicting the venoms pathophysiology and clinical treatments.

Comparative venom analysis between melanistic and normally-colored phenotypes of the common adder (Vipera berus)

“…Analysis of Vipera berus venom samples from melanistic (MEL) and cryptic (CRY) phenotypes by SDS-PAGE under (A) reducing and (B) non-reducing conditions. Putative toxin families were predicted according to described Viperidae toxin families, their polymerization potential, and the previously reported composition of V. berus venom (Al-Shekhadat et al, 2019; Bocian et al, 2016; Damm et al, 2024; Latinović et al, 2016). Abbreviations: 5N, 5′-nucleotidase; AP, aminopeptidase; CTL, C-type lectin including snaclec and C-type lectin-related proteins; DC-Fragments, Disintegrin-like/cysteine-rich protein (fragments); HYAL, hyaluronidase; LAAO, l -amino acid oxidase; NGF, nerve-growth factor; PLA 2 , phospholipase A 2 ; PLB, phospholipase B-like; PDE, phosphodiesterase; QC, glutaminyl cyclase; svMP, snake venom metalloprotease; svSP, snake venom serine proteinase; VEGF, vascular endothelial growth factor.…”

“…The analysis of the venom profiles through SDS-PAGE at reducing and non-reducing conditions allowed us to identify putative venom toxins based on known Viperidae venom components, their potential to form multimeric complexes, and the previously reported venom composition of V. berus (Al-Shekhadat et al, 2019; Bocian et al, 2016; Damm et al, 2024; Latinovićet al, 2016). The MEL banding pattern was generally more intense than its CRY counterpart, especially at ∼31 and 47–70 kDa in reducing gels and at 76–115 kDa in non-reducing gels.…”

“…Although the analysis of a single specimen is not representative, the study nevertheless showed a similar trend to our observations, with the venom from the melanistic snake yielding more intense bands corresponding to larger toxins. However, the venom composition of V. berus berus specimens from Russia (Al-Shekhadat et al, 2019; Latinovićet al, 2016) and the Slovakian Republic (Bocian et al, 2016), as well as one V. berus barani specimen from Türkiye (Damm et al, 2024), revealed remarkable quantitative diversity for PLA 2 (10% (Latinovićet al, 2016), 17.9% (Damm et al, 2024), 25.3 % (Al-Shekhadat et al, 2019), 59% (Bocian et al, 2016)), as well as svMP (0.2% (Damm et al, 2024), 3.15% (Bocian et al, 2016), 17.2% (Al-Shekhadat et al, 2019), 19% (Latinovićet al, 2016)) and svSP (15% (Bocian et al, 2016), 16.2% (Al-Shekhadat et al, 2019), 31% (Latinovićet al, 2016), 46.1% (Damm et al, 2024)). In relation to this extreme compositional variation across the sampling sites in previous studies, the venom variation we observed by SDS-PAGE and RP-HPLC was marginal and only affected the abundance of certain fractions rather than their overall diversity.…”

“…The venom profile of V. berus has been analyzed (in a few cases using modern venomics technologies) and seems to match the typical viperine profile dominated by members of the phospholipase A 2 (PLA 2 ) family, snake venom metalloproteases (svMPs), serine proteinases (svSPs) and C-type lectins (CTLs), including snaclecs and C-type lectin-related proteins (Al-Shekhadat et al, 2019; Bocian et al, 2016; Latinovićet al, 2016). V. berus also appears to show intraspecific venom variation because the proportion and abundance of dominant and lesser toxin families varies between studies and according to the origin (Damm et al, 2021) and assigned subspecies (Damm et al, 2024) of each specimen.…”