Reclassification of 11 Members of the Family Rhodobacteraceae at Genus and Species Levels and Proposal of sp. nov.

A novel Gram-stain-negative, aerobic, motile bacterial strain, D13-10-4-6, was isolated from the bark sample of × . The strain could grow at 15-35°C, at pH 6-10 and in 0-4% (w/v) NaCl, and the strain tested positive for oxidase and catalase activities. The main polar lipids were phosphatidylmonomethylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. The main respiratory quinone was Q-10, and the predominant fatty acid was C ω7. The phylogenetic analyses showed that the strain belonged to the genus of the family Rhodobacteraceae. The family Rhodobacteraceae is an ecologically diverse group that includes bacteria from aquatic to terrestrial ecosystems. As a consequence, the classification of the family Rhodobacteraceae is difficult, not least when the early taxonomy work relied heavily on 16S rRNA gene analysis. Recently, the taxonomic status of many members of the family has been revised based on the genome analysis; however, there are still some classification conflicts due to the lack of genome sequences and parallel publication time. In this study, phylogenetic trees based on 16S rRNA gene, B gene, and 120 concatenated proteins, the average amino acid identity (AAI) and percentage of conserved proteins (POCP) have been used for the analysis of strain D13-10-4-6 and other members of 15 genera within the family to further clarify their taxonomic relationships. For the data of phylogeny, AAI, and POCP, the taxonomic proposals are (1) reclassification of as the type species of a novel genus, gen. nov., as comb. nov.; (2) reclassification of , , into a novel genus, gen. nov., as comb. nov., comb. nov., comb. nov.; (3) reclassification of into the genus as comb. nov.; (4) reclassification of , , and into the genus as comb. nov., comb. Nov., and comb. nov.; (5) reclassification of into the genus as comb. nov.; (6) classification of strain D13-10-4-6 as a novel species of the genus , for which the name sp. nov. is proposed, the type strain is D13-10-4-6 (= CFCC 12033 = KCTC 82215).