Rubellimicrobium mesophilum sp. nov., a mesophilic, pigmented bacterium isolated from soil

Abstract

A pink- to light-reddish-pigmented, aerobic, pointed, budding, mesophilic strain designated MSL-20T was isolated from soil from Bigeum island, Korea. The isolate was Gram-negative. Cells were motile rods without flagella. The temperature and pH for growth were 20-37 °C (optimum 28 °C) and pH 7.0-11.0 (optimum pH 7.0 ± 0.2). Q-10 was the predominant respiratory ubiquinone. The major fatty acids were C16:0 (37 %), C18:1ω7c (36%) and 11-methyl C18:1ω7c (12%), Phylogenetic analysis based on the 16S rRNA gene sequence revealed that Rubellimicrobium thermophilum DSM 16684T was its closest neighbour (95.2 % similarity); the isolate had less than 97.0% similarity to all species with validly published names. Chemotaxonomic data were determined for this isolate, including peptidoglycan type, diagnostic sugar composition, fatty acid profiles, ubiquinones and polar lipids; the results supported the affiliation of strain MSL-20T to the genus Rubellimicrobium. The DNA G + C content was 72.3 mol%. On the basis of the phenotypic, chemotaxonomic and phylogenetic data, strain MSL-20T represents a novel species of the genus Rubellimicrobium, for which the name Rubellimicrobium mesophilum sp. nov. is proposed. The type strain is MSL-20T (=KCTC 22012T = DSM 19309T).