Venom comparisons of endemic and micro-endemic speckled rattlesnakes Crotalus mitchellii, C. polisi and C. thalassoporus from Baja California Peninsula

• Published in: Toxicon (Oxford) 2023-03, Vol.224, p.107030-107030, Article 107030
• Main Authors: Arnaud-Franco, Gustavo, Ríos-Castro, Emmanuel, Velasco-Suárez, Andrea, García-de León, Francisco J., Beltrán, Luis F., Carbajal-Saucedo, Alejandro
• Format: Article
• Language: English
• Subjects: Animals; Cattle; Crotalid Venoms - metabolism; Crotalus; Crotalus - metabolism; Humans; Island; Metalloproteases - metabolism; Mexico; Mitchellii; Phospholipases - metabolism; Polisi; Proteins - metabolism; Proteome; Serine Proteases - metabolism; Thalassoporus
• ISSN: 0041-0101; 1879-3150
• DOI: 10.1016/j.toxicon.2023.107030

A high diversity of rattlesnake species can be found in the Baja California peninsula and the island of the Gulf of California, nevertheless, their venom has been poorly evaluated. The aim of this work was to present the first characterization of endemic Crotalus mitchellii, micro endemic C. polisi and C. thalassoporus venoms. All samples provoke human plasma coagulation showing doses in the rank of 2.3–41.0 μg and also produce rapid hydrolysis of the alpha chain of bovine fibrinogen while the beta chain is attacked at larger incubation periods by C. polisi and especially by C. thalassoporus. Phospholipase activity ranging from 23.2 to 173.8 U/mg. The venoms of C. thalassoporus and C. polisi show very high hemorrhagic activity (from 0.03 to 0.31 μg). A total of 130 toxin-related proteins were identified and classified into ten families. Crotalus mitchellii venom was characterized by high abundance of crotoxin-like and other phospholipase proteins (34.5%) and serine proteinases (29.8%). Crotalus polisi showed a similar proportion of metalloproteinases (34%) and serine proteinases (22.8%) components with important contribution of C-type lectins (14.3%) and CRiSP (14.0%) proteins. Venom of C. thalassoporus is dominated by metalloproteases that amount to more than 66% of total toxin proteins. These results provide a foundation for comprehending the biological, ecological and evolutionary significance of venom composition of speckled rattlesnake from the Baja California peninsula. [Display omitted] •First biological and biochemical analysis of endemic Crotalus mitchellii and micro endemic C. polisi and C. thalassoporus.•Peninsular C. mitchellii venom provoke coagulation and is dominated by phospholipase and serine proteinase toxins.•C. polisi and C. thalassoporus venoms show high hemorrhagic activity and are dominated by metallo and serine proteases.