Detection, quantitation and stability of the beta haemolysin of Aeromonas spp.

Amongst 58 isolates of motile aeromonads evaluated for the ability to produce beta haemolysin, haemolytic activity was significantly associated with strains belonging to the Aeromonas hydrophila and A. sobria groups. Of erythrocytes from nine animal species tested, mouse red blood cells provided the best indicator system for detection of beta-haemolysin activity. Furthermore, differences in the stability of the beta haemolysins of selected A. sobria and A. hydrophila isolates at different temperatures, and in the presence of urea or dithiothreitol were observed.