Chryseomicrobium imtechense gen. nov., sp. nov., a new member of the family Planococcaceae

Abstract

A Gram-stain-positive, rod-shaped, yellow, non-motile, non-spore-forming, strictly aerobic bacterial strain, designated MW 10T, was isolated from seawater of the Bay of Bengal, India, and was subjected to a polyphasic taxonomic study. Analysis of the 16S rRNA gene sequence revealed that strain MW 10T showed highest similarity to the type strains of Psychrobacillus psychrodurans (96.15 %) and Psychrobacillus psychrotolerans (96.01 %) and showed less than 96 % similarity to members of the genera Paenisporosarcina, Planococcus, Sporosarcina and Planomicrobium. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain MW 10T formed a clade separate from members of closely related genera. The morphological, physiological and chemotaxonomic characteristics of strain MW 10T differed from those of members of closely related genera. The major fatty acid in strain MW 10T was iso-C15 : 0 and the menaquinones were MK-7 (48.4 %), MK-8 (32.3 %), MK-7(H2) (13.7 %) and MK-6 (5.6 %). The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unknown phospholipid, an unknown lipid and an unknown glycolipid. The cell-wall peptidoglycan type was l-Lys–d-Asp. The genomic DNA G+C content (53.4 mol%) of strain MW 10T was significantly different from those of members of closely related genera. On the basis of its morphological, physiological and chemotaxonomic characteristics as well as our phylogenetic analysis, we conclude that strain MW 10T is a member of a novel genus and species, for which the name Chryseomicrobium imtechense gen. nov., sp. nov., is proposed. The type strain of Chryseomicrobium imtechense is MW 10T ( = MTCC 10098T  = JCM 16573T).