Lysinimicrobium mangrovi gen. nov., sp. nov., an actinobacterium isolated from the rhizosphere of a mangrove

Abstract

A novel strain of Gram-staining-positive bacterium, designated HI08-69T, was isolated from the rhizosphere of a mangrove on Iriomote Island, Japan, and its taxonomic position was investigated by a polyphasic approach. The strain had peptidoglycan of the A4α type, with lysine as the diagnostic diamino acid. The predominant menaquinone was demethylmenaquinone DMK-9(H4) and the major fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and C16 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and an unidentified polar lipid but minor amounts of other polar lipids were also detected. The genomic DNA G+C content of strain HI08-69T was 71.7 mol%. In phylogenetic analyses based on 16S rRNA gene sequences, the novel strain and members of the genus Demequina formed a monophyletic cluster, with pairwise sequence similarities of 95.6–96.8 %. However, strain HI08-69T was clearly distinguishable from all established members of the genus Demequina in terms of several chemotaxonomic characteristics. On the basis of the phenotypic and genotypic characteristics, strain HI08-69T represents a novel species in a new genus for which the name Lysinimicrobium mangrovi gen. nov., sp. nov. is proposed. The type strain of the type species is HI08-69T ( = NBRC 105856T = DSM 24868T).