Biological and Proteolytic Variation in the Venom of Crotalus scutulatus scutulatus from Mexico
Miguel Borja,
Edgar Neri-Castro,
Gamaliel Castañeda-Gaytán,
Jason L. Strickland,
Christopher L. Parkinson,
Juan Castañeda-Gaytán,
Roberto Ponce-López,
Bruno Lomonte,
Alejandro Olvera-Rodríguez,
Alejandro Alagón,
Rebeca Pérez-Morales
Affiliations
Miguel Borja
Facultad de Ciencias Biológicas, Universdad Juárez del Estado de Durango, Av. Universidad s/n. Fracc. Filadelfia, C.P. 35010 Gómez Palacio, Dgo., Mexico
Edgar Neri-Castro
Instituto de Biotecnología, Universidad Nacional Autónoma de Mexico, Avenida Universidad 2001, Chamilpa, C.P. 62210 Cuernavaca, Mor., Mexico
Gamaliel Castañeda-Gaytán
Facultad de Ciencias Biológicas, Universdad Juárez del Estado de Durango, Av. Universidad s/n. Fracc. Filadelfia, C.P. 35010 Gómez Palacio, Dgo., Mexico
Jason L. Strickland
Department of Biology, University of Central Florida, 4000 Central Florida Blvd., Orlando, FL 32816, USA
Christopher L. Parkinson
Department of Biological Sciences and Department of Forestry and Environmental Conservation, Clemson University, 190 Collings St., Clemson, SC 29634, USA
Juan Castañeda-Gaytán
Facultad de Ciencias Biológicas, Universdad Juárez del Estado de Durango, Av. Universidad s/n. Fracc. Filadelfia, C.P. 35010 Gómez Palacio, Dgo., Mexico
Roberto Ponce-López
Instituto de Biotecnología, Universidad Nacional Autónoma de Mexico, Avenida Universidad 2001, Chamilpa, C.P. 62210 Cuernavaca, Mor., Mexico
Bruno Lomonte
Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José 11501, Costa Rica
Alejandro Olvera-Rodríguez
Instituto de Biotecnología, Universidad Nacional Autónoma de Mexico, Avenida Universidad 2001, Chamilpa, C.P. 62210 Cuernavaca, Mor., Mexico
Alejandro Alagón
Instituto de Biotecnología, Universidad Nacional Autónoma de Mexico, Avenida Universidad 2001, Chamilpa, C.P. 62210 Cuernavaca, Mor., Mexico
Rebeca Pérez-Morales
Facultad de Ciencias Químicas, Universidad Juárez del Estado de Durango, Av. Artículo 123 s/n. Fracc. Filadelfia, Apartado Postal No. 51, C.P. 35010 Gómez Palacio, Dgo., Mexico
Rattlesnake venoms may be classified according to the presence/absence and relative abundance of the neurotoxic phospholipases A 2 s (PLA 2 s), such as Mojave toxin, and snake venom metalloproteinases (SVMPs). In Mexico, studies to determine venom variation in Mojave Rattlesnakes (Crotalus scutulatus scutulatus) are limited and little is known about the biological and proteolytic activities in this species. Tissue (34) and venom (29) samples were obtained from C. s. scutulatus from different locations within their distribution in Mexico. Mojave toxin detection was carried out at the genomic (by PCR) and protein (by ELISA) levels for all tissue and venom samples. Biological activity was tested on representative venoms by measuring LD 50 and hemorrhagic activity. To determine the approximate amount of SVMPs, 15 venoms were separated by RP-HPLC and variation in protein profile and proteolytic activity was evaluated by SDS-PAGE (n = 28) and Hide Powder Azure proteolytic analysis (n = 27). Three types of venom were identified in Mexico which is comparable to the intraspecific venom diversity observed in the Sonoran Desert of Arizona, USA: Venom Type A (∼Type II), with Mojave toxin, highly toxic, lacking hemorrhagic activity, and with scarce proteolytic activity; Type B (∼Type I), without Mojave toxin, less toxic than Type A, highly hemorrhagic and proteolytic; and Type A + B, containing Mojave toxin, as toxic as venom Type A, variable in hemorrhagic activity and with intermediate proteolytic activity. We also detected a positive correlation between SVMP abundance and hemorrhagic and proteolytic activities. Although more sampling is necessary, our results suggest that venoms containing Mojave toxin and venom lacking this toxin are distributed in the northwest and southeast portions of the distribution in Mexico, respectively, while an intergradation in the middle of both zones is present.
