Gordonia sediminis sp. nov., an actinomycete isolated from mangrove sediment.

The taxonomic position of an actinomycete designated AMA 120T, isolated from mangrove sediment, was clarified by phenotypic, chemotaxonomic and phylogenetic studies. The 16S rRNA gene sequence revealed that strain AMA 120T was most closely related to Gordonia rhizosphera NBRC 16068T (98.9 %), Gordonia polyisoprenivorans NBRC 16320T (98.1 %) and Gordonia bronchialis NBRC 16047T (98.1 %). A fragment of the gyrB gene of strain AMA 120T formed a distinct phyletic line with G. rhizosphera NBRC 16068T (95.4 %). Strain AMA 120T contained meso-diaminopimelic acid, arabinose and galactose as cell-wall components, and MK-9(H2) was the predominant menaquinone. The polar lipid profile for this strain consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and two unidentified phospholipids. Mycolic acid was present. The major fatty acids were C16 : 0, C18 : 1ω9c and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The DNA-DNA relatedness values between AMA 120T and close species were below 70 %. There was an obvious distinction in the average nucleotide identity distribution between strain AMA 120T and its closely related strains at around 75-92%. The DNA G+C content of strain AMA 120T was 66.6 mol%. These results, coupled with the phenotypic and chemotaxonomic data, indicated that strain AMA 120T represents a novel species of the genus Gordonia, for which the name Gordoniasediminis sp. nov. is proposed. The type strain is AMA 120T (=TBRC 7109T=NBRC 113236T).