Tropicimonas aquimaris sp. nov., isolated from seawater, and emended description of the genus Tropicimonas Harwati et al. 2009

Abstract

A Gram-staining-negative, aerobic, non-motile and rod-shaped bacterial strain, designated DPG-21(T), was isolated from seawater from the South Sea in Korea, and investigated using a polyphasic taxonomic approach. Strain DPG-21(T) grew optimally at pH 7.0-8.0, at 30 °C and in the presence of 2% (w/v) NaCl. In a neighbour-joining phylogenetic tree based on 16S rRNA gene sequences, strain DPG-21(T) clustered with Tropicimonas isoalkanivorans B51(T) (with a sequence similarity of 97.1%); the novel strain showed lower 16S rRNA gene sequence similarities (<95.4%) with the other species included in the tree. The mean DNA-DNA relatedness value between strain DPG-21(T) and T. isoalkanivorans DSM 19548(T) was 12%. The predominant ubiquinones of strain DPG-21(T) were Q-10 and Q-9 while C(18:1)ω7c was the strain's major fatty acid. The polar lipid profile of strain DPG-21(T) was similar to that of T. isoalkanivorans DSM 19548(T). The genomic DNA G+C content of the novel strain was 69.6 mol%. Some phenotypic properties and the phylogenetic and genetic data indicated that strain DPG-21(T) was distinct from T. isoalkanivorans and represents a novel species of the genus Tropicimonas, for which the name Tropicimonas aquimaris sp. nov. is proposed. The type strain is DPG-21(T) (=KCTC 23424(T)=CCUG 60524(T)).