Characterization of facultative sulfur-oxidizing Marinobacter sp. BR13 isolated from marine sediment of Yellow Sea, Korea

Marine sediment was collected from the Yellow Sea, Korea, and enriched using 1 mM thiosulfate under aerobic conditions. After 2 weeks, a facultative sulfur-oxidizing strain, BR13, was isolated. Phylogenetic analysis based on the 16S rRNA gene sequence showed that this strain belonged to the genus Marinobacter in the gamma-proteobacteria and was most closely related to Marinobacter pelagius H225T (99.5% 16S rRNA gene sequence similarity) and Marinobacter koreensis DD-M3T (97.7% 16S rRNA gene sequence similarity). The isolate was a sulfur-oxidizer, Gram-negative, aerobic, and slightly halophilic bacterium and grew in 0.5–9% NaCl at 7–37ºC. Strain BR13 shared some physiological and biochemical properties with Marinobacter pelagius H225T and Marinobacter koreensis DD-M3T. The G+C content of the genomic DNA of strain BR13 was 58.4 mol%. Strain BR13 possessed C16:0, summed feature 4 (C16:1ω7c and/or C15:1iso 2OH), C16:0 N alcohol, and C18:1ω9c as the major cellular fatty acids. Our results showed that strain BR13 (=KCTC 22253 =JCM 15135) is a novel facultative sulfur-oxidizing strain in the genus of Marinobacter.