Albidovulum xiamenense sp. nov., a moderately thermophilic bacterium from a terrestrial hot spring.

An aerobic, motile, moderately thermophilic, rod-shaped bacterium, strain YBY-7(T), was isolated from a terrestrial hot spring of a garden exhibition located in Xiamen City, Fujian Province, People's Republic of China. Cells of strain YBY-7(T) were Gram-negative, irregular rods, 2-6 µm long and 0.4-0.6 µm wide, with polar flagella, and the organism formed beige colonies. The temperature and pH ranges for growth of strain YBY-7(T) were 28-65 °C (optimum 50-58 °C) and pH 6.5-9.5 (optimum pH 7.5-8.5). Growth occurred in the presence of 5.5% NaCl (optimum 3.0%). Phylogenetic analysis based on the 16S rRNA gene sequence revealed that Albidovulum inexpectatum FRR-10(T) was its closest neighbour (95.9% similarity). Ubiquinone (Q-10) was the sole respiratory quinone and the DNA G+C content of strain YBY-7(T) was 70.6 mol%. The predominant polar lipids were phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine. The major fatty acids were C(18:1)ω7c (29.3%), C(19:0) cyclo ω8c (25.6%), C(18:0) (23.6%) and C(16:0) (9.6%). Based on its physiological characteristics and our phylogenetic analysis, we propose that strain YBY-7(T) represents a novel species of the genus Albidovulum, for which the name Albidovulum xiamenense sp. nov. is proposed, with the type strain YBY-7(T) (=MCCC 1A06317(T) =CGMCC 1.10789(T) =LMG 26247(T)).