DNA RELATEDNESS AND CHEMOTAXONOMIC FEATURE OF AEROBIC BACTERIOCHLOROPHYLL-CONTAINING BACTERIA ISOLATED FROM COASTS OF AUSTRALIA

Thirty-seven strains of aerobic bacteriochlorophyll (Bchl)-containing bacteria (ABB) isolated previously from the coasts of Australia were c ompared with the authentic ABB, Erthrobacter and Roseobacter. They wer e divided into four groups (GI-GIV) on the basis of cell color, absorp tion spectrum type of Bchl in the near infrared region and cell morpho logy. Furthermore, some members of GI and GII were separated genetical ly into 3 and 4 respectively based on the levels of DNA homology, Amon g the 37 strains tested, only strain OCh273, a strain of GIV, showed c omparatively high DNA homologies (ca. 50%) with the type strains of Ro seobacter spp., and the other 36 strains showed low DNA homologies (1 to 12%) with the type strains of Erythrobacter longus and Roseobacter spp. The ubiquinone system of all strains was Q-10 and the major cellu lar fatty acid (CFA) was C-18:1 acid except in five strains. The major CFA in four (OCh208, OCh229, OCh246 and OCh268) of the five strains w as C-17:1 and that of the remaining strain (OCh492) was C-16:0 The gua nine plus cytosine contents of the DNA of the 37 test strains examined were from 53.0 to 74.8 mol%.