Arenibacter gen. nov., new genus of the family Flavobacteriaceae and description of a new species, Arenibacter latericius sp nov.

Five dark-orange-pigmented, Gram-negative, rod-shaped, non-motile, aerobic bacterial strains were isolated from sandy sediment samples collected in th e South China Sea in the Indian ocean, from a holothurian, Apostichopus jap onicus, in the Sea of Japan and from a brown alga, Chorda filum, from the S ea of Okhotsk in the Pacific Ocean. Phenotypic data were collected, demonst rating that the bacteria are chemo-organotrophic and require seawater-based media for growth. Polar lipids were analysed and 27% of the total extract comprised phosphatidylethanolamine as the major component. The predominant cellular fatty acids were branched-chain saturated and unsaturated [i-C15:0 , i-C15:1, a-C15:0, C15:0, C16:1(n-7)]. The DNA base composition was 37.5-3 8.2 mol % G+C. The level of DNA homology of the five isolates was 83-94%, i ndicating that these isolates belong to the same species. A 16S rDNA sequen ce of the type strain KMM 426(T) was determined and phylogenetic analysis, based on neighbour-joining and Fitch-Margoliash methods, revealed that the type strain formed a distinct phyletic line in a clade corresponding to the family Flavobacteriaceae and represented a new genus. From the results of this polyphasic taxonomic analysis, it is proposed that the bacterial strai ns be classified in a new genus, Arenibacter gen. nov., and species, Arenib acter latericius sp. nov. The type strain is KMM 426(T) (VKM B 2137D(T) = L MG 19694(T) = CIP 106861(T)).