title: Electrophoretic profiles and biological activities: intraspecific variation in the venom of the Malayan pit viper (Calloselasma rhodostoma)
abstract: The Malayan pit viper (Calloselasma rhodostoma) is of major clinical significance both as a leading cause of snakebite and as the source of ancrod (Arvin). Although its venom has been extensively studied, the degree to which venom composition varies between individuals is poorly known. We individually analysed the venoms of over 100 C. rhodostoma using isoelectric focusing. In all populations, females produced an intense band that was absent from all males, and significant ontogenetic variation was detected. Principal components analysis of the banding profiles also revealed strong geographic variation, which was significantly congruent with variation in the biological activities of the venom (phosphodiesterase, alkalinephosphoesterase, L-amino acid oxidase, arginine ester hydrolase, 5'-nucleotidase, thrombin-like enzyme, haemorrhagic activity). Studies of captive-bred snakes indicate that the intraspecific variation in venom is genetically inherited rather than environmentally induced. The intraspecific variation in venom composition and biological activity could be of applied importance to snakebite therapy, both in correct diagnosis of the source of envenomation and in the development of a more effective antivenom. Greater attention should be given to the source of C. rhodostoma venom used in research to ensure reproducibility of results.
authors.affiliation: School of Biological Sciences, University of Wales, Bangor, Gwynedd, UK.
authors.forename: J C
authors.initials: JC
authors.lastname: Daltry
authors.forename: G
authors.initials: G
authors.lastname: Ponnudurai
authors.forename: C K
authors.initials: CK
authors.lastname: Shin
authors.forename: N H
authors.initials: NH
authors.lastname: Tan
authors.forename: R S
authors.initials: RS
authors.lastname: Thorpe
authors.forename: W
authors.initials: W
authors.lastname: Wüster
mesh_terms: D015720:5'-Nucleotidase / Q000378:metabolism; D000594:Amino Acid Oxidoreductases / Q000378:metabolism; D000818:Animals; D002265:Carboxylic Ester Hydrolases / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced; D007525:Isoelectric Focusing; D050830:L-Amino Acid Oxidase; D008296:Malaysia; D008297:Male; D051379:Mice; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism; D015203:Reproducibility of Results; D012737:Sex Factors; D012911:Snakes; D013045:Species Specificity; D013917:Thrombin / Q000378:metabolism; D014757:Viper Venoms / Q000201:enzymology* / Q000378:metabolism / Q000633:toxicity
chemical_list: D014757:Viper Venoms; D000594:Amino Acid Oxidoreductases; D050830:L-Amino Acid Oxidase; C019724:arginine esterase; D002265:Carboxylic Ester Hydrolases; D010744:Phosphoric Monoester Hydrolases; D015720:5'-Nucleotidase; D010727:Phosphoric Diester Hydrolases; D013917:Thrombin