Muscle proteins were isolated from 7 western Atlantic and 10 Pacific Ocean Penaeus species encompassing 6 subgenera utilizing isoelectric focusing. Protein banding patterns of individuals from the 17 species were distinguishable. A high resolution gradient of pH 4.5-5 was required to separate complex banding patterns and facilitate identification among species possessing similar banding patterns. Most species were characterized by the presence of 2-6 major protein bands in the pH 4.62-4.95 range. Densitometric analysis provided a graphic representation of differences in band migration, number, and intensity among the 17 Penaeus species. Due to the large number of protein bands and their proximity to each other, reference densitometric tracings were necessary to consistently distinguish all species. General protein patterns observed in this study appeared to substantiate recent systematic reclassifications within the genus Penaeus.
