Agromyces mangrovi sp. nov., a novel actinobacterium isolated from the rhizosphere of a mangrove.

A novel actinobacterium, designated HIr16-25T, was isolated from the rhizosphere soil of a mangrove growing on Iriomote Island in Japan. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain HIr16-25T fell within the cluster of the members of the genus Agromyces and the highest sequence similarity value was observed with Agromyces rhizospherae IFO 16236T (98.6%). Strain HIr16-25T possessed L-2,4-diaminobutyric acid as a diagnostic diamino acid of the peptidoglycan, and MK-12 and MK-11 as the predominant menaquinones. The major fatty acids were identified as iso-C16:0, anteiso-C15:0 and anteiso-C17:0 and the principal polar lipids were phosphatidylglycerol and one glycolipid. These chemotaxonomic features matched well those described for the members of the genus Agromyces. Meanwhile, the result of DNA-DNA hybridization and the presence of differential phenotypic characteristics between strain HIr16-25T and the type strain of A. rhizospherae indicated that strain HIr16-25T be classified as a novel species of the genus Agromyces. Therefore, we propose strain HIr16-25T to represent a novel species of the genus Agromyces, with the name Agromyces mangrovi sp. nov. The type strain is HIr16-25T (= NBRC 112812T = TBRC 7760T).