Polypeptide and antigen profiles of Cryptobia salmositica, C. oullocki and C. catostomi (Kinetoplastida: Sarcomastigophora) isolated from fishes

Abstract

Polypeptide and antigen profiles of Cryptobia salmositica (virulent and avirulent strains). C. bullocki and C. catostomi were compared using SDS-PAGE and Western immunoblot. The avirulent strain of C. salmositica had 5 fewer bands than the virulent strain (21 bands) which is, perhaps, related to loss of virulence. C. catostomi had the highest number of bands (23) and a different banding pattern than the other 2 species. Although the 3 species had several bands of similar molecular mass, they were antigenically distinct. The avirulent and virulent strains of C. saln~ositica had several cross-reacting bands when probed with antiserum against the virulent strain. There were, however, no cross-reactions between C. salmositica and the other 2 species except for a band of 66 kD. We tentatively suggest that pathogenic and non-pathogenic species of Cryptobia have different polypeptide profiles and are antigenically distinct. SDS-PAGE followed by Western immunoblot may be a useful procedure to distinguish species of Cryptobia from various hosts and also to determine their phylogenetic relationships .