LUMINESCENT BACTERIAL SYMBIONTS AND COMMENSALS OF LUMINESCENT AND NONLUMINESCENT MARINE ANIMALS OF THE INDIAN-OCEAN

Approximately 100 fish belonging to 24 families and several representa tives of cephalopods, prawns, and euphausiids were investigated for th e presence of luminescent bacteria. Species identification of isolated luminescent bacteria was performed, and the frequency and ratio of th eir occurrence in the gastrointestinal microflora of marine animals we re determined. Luminescent bacteria occurred in 23 - 65% of the fish, depending on the habitat depth, and their ratio varied from 8 to 60% o f the total gastrointestinal microflora of fish. The free-living lumin escent bacteria were found in 50% of the seawater samples from depths down to 1000 m. The luminescent bacterium Photobacterium phosphoreum w as dominant among the isolated cultures.