Aestuariimicrobium kwangyangense gen. nov., sp. nov., an ll-diaminopimelic acid-containing bacterium isolated from tidal flat sediment

Abstract

Four Gram-positive, catalase-positive, short rod- or coccoid-shaped bacterial strains, R27T, R44, R45 and R47, were isolated from an enrichment culture with diesel oil-degradation activity and their taxonomic positions were investigated using a polyphasic approach. Phenotypic, phylogenetic and genetic similarities indicated that strains R27T, R44, R45 and R47 belong to the same species. Phylogenetic analysis based on 16S rRNA gene sequences showed that the four strains form a distinct evolutionary lineage within the family Propionibacteriaceae. The novel four strains had cell-wall peptidoglycan based on ll-diaminopimelic acid, MK-9(H4) as the predominant menaquinone and anteiso-C15 : 0 as the major cellular fatty acid. The DNA G+C contents were 68.8–69.2 mol%. These chemotaxonomic properties, together with phylogenetic distinctiveness, distinguish the four novel strains from recognized members of the family Propionibacteriaceae. On the basis of phenotypic, chemotaxonomic, phylogenetic and genetic data, strains R27T, R44, R45 and R47 are classified as representatives of a new genus and novel species, Aestuariimicrobium kwangyangense gen. nov., sp. nov., within the family Propionibacteriaceae. The type strain of Aestuariimicrobium kwangyangense sp. nov. is R27T (=KCTC 19182T=JCM 14204T).