Tropicimonas sediminicola sp. nov., isolated from marine sediment.

A novel Gram-negative, obligately aerobic, non-motile, rod-shaped bacterium, strain M97(T), was isolated from marine sediment of a cage-cultured ark clam farm on the south coast of Korea. Strain M97(T) was positive for oxidase and catalase. Optimal growth occurred at 37 °C, with 1-2 % (w/v) NaCl and at pH 7-8. The main cellular fatty acids were C(16 : 0), C(18 : 1)ω7c, C(12 : 0) 3-OH and cyclo-C(19 : 0)ω8c. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, an unknown aminolipid and three unknown lipids. The predominant respiratory quinone was ubiquinone-10 (Q-10). Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain M97(T) belongs to the genus Tropicimonas, with highest sequence similarity to Tropicimonas aquimaris DPG-21(T) (99.0 %). The DNA G+C content of strain M97(T) was 68.5 mol%. Mean DNA-DNA relatedness between strain M97(T) and T. aquimaris DPG-21(T) was 46 ± 10 %. Based on phylogenetic, phenotypic and genotypic analyses, strain M97(T) is considered to represent a novel species of the genus Tropicimonas, for which the name Tropicimonas sediminicola sp. nov. is proposed. The type strain is M97(T) ( = KACC 15544(T) = JCM 17731(T)).