Description Of Rhodobacter Azollae Sp Nov And Rhodobacter Lacus Sp Nov.

Three strains (JA826(T), JA912(T) and JA913), which were yellowish brown colour, rod to oval shaped, Gram-stain-negative, motile, phototrophic bacteria with a vesicular architecture of intracytoplasmic membranes, were isolated from different pond samples. The DNA G+C content of the three strains was between 64.6 and 65.5 mol%. The highest 16S rRNA gene sequence similarity of all three strains was with the type strains of the genus Rhodobacter sensu stricto in the family Rhodobacteraceae. Strain JA826(T) had highest sequence similarity with Rhodobacter maris JA276(T) (98.5 %), Rhodobacter viridis JA737(T) (97.5 %) and other members of the genus Rhodobacter (<97 %). Strain JA912(T) had highest sequence similarity with Rhodobacter viridis JA737(T) (99.6 %), Rhodobacter sediminis N1(T) (99.3 %), Rhodobacter capsulatus ATCC 11166(T) (98.8 %) and less than 97% similarity with other members of the genus Rhodobacter. The 16S rRNA gene sequence similarity between strains JA826(T) and JA912(T) was 96.9 %. DNA-DNA hybridization showed that strains JA826(T) and JA912(T) (values among themselves and between the type strains of nearest members <44 %) did not belong to any of the nearest species of the genus Rhodobacter. However, strains JA912(T) and JA913 were closely related (DNA-DNA hybridization value > 90 %). The genomic distinction was also supported by differences in phenotypic and chemotaxonomic characteristics in order to propose strains JA826(T) (= KCTC 15478(T) = LMG 28758(T)) and JA912(T) (= KCTC 15475(T) = LMG 28748(T)) as new species in the genus Rhodobacter sensu stricto with the names Rhodobacter lacus and Rhodobacter azollae, respectively.