Identification of Shark Species by Polyacrylamide Gel Isoelectric Focusing of Sarcoplasmic Proteins

Abstract

Abstract Isoelectric focusing of muscle proteins is a fast and highly reproducible technique that has been used to identify fish species. Application of isoelectric focusing of sarcoplasmic proteins is described for identification of shark species. Sarcoplasmic protein patterns from muscle tissue of single individuals from 26 shark species and multiple individuals from 2 of the 26 shark species are shown on 1 mm thick polyacrylamide gels. Eight of these species showed pattern polymorphisms in major and minor bands; however, no individual within a species displayed the same protein pattern as that in any other species. Protein banding patterns of each species were visually distinguishable, and patterns generated on the basis of defined parameters were analyzed by a computer to obtain isoelectric points of bands, to produce schematic representations of banding patterns, and to distinguish between species-specific patterns. Isoelectric focusing appears to be an excellent method for identifying sharks. Additionally, isoelectric focusing of muscle proteins is readily applicable as a forensic tool to identify the species of shark samples received as evidence for law enforcement actions supporting shark fishery management plans.