Roseibium algae sp. nov., isolated from a marine alga (Grateloupia sp.)

A novel Gram-stain-negative, rod-shaped, non-spore-forming, aerobic, motile bacterium with a single polar or subpolar flagellum, designated strain H3510 T , was isolated from marine alga collected on sea shore of Yantai, PR China. The organism grew optimally at 28 °C and pH 7.0 and in presence of 3.0 % (w/v) NaCl. The strain exhibited positive catalase activity but negative oxidase and nitrate reduction activities. The predominant cellular fatty acids were C 18 : 1 ω 7 c and/or C 18 : 1 ω 6 c , 11-methyl C 18 : 1 ω 7 c , and C 16 : 0 . Additionally, the major polar lipids were phosphatidylglycerol, phosphatidylmonomethylethanolamine, diphosphatidylglycerol, and phosphatidylethanolamine; the respiratory quinone was ubiquinone 10 (Q-10). The genomic DNA G+C content of strain H3510 T was 54.2%. The novel strain showed the closest relationship with Roseibium polysiphoniae KMM 9699 T with 98.2 % 16S rRNA gene sequence similarity. The calculated values for average nucleotide identity and DNA–DNA hybridization between strain H3510 T and the phylogenetically related Roseibium species were in the range of 71.3–74.9 % and 13.7–19.9 %, respectively. Based on polyphasic analyses, strain H3510 T was identified as representing a novel species of the genus Roseibium , for which the name Roseibium algae sp. nov. is proposed. The type strain is H3510 T (=KCTC 8206 T =MCCC 1K04325 T ). The heterologously expressed inositol 2-dehydrogenase gene from strain H3510 T displayed high oxidation activity on myo -inositol and showed potential in the production of rare stereoisomers of inositol, such as scyllo -inositol.