Gilvimarinus gilvus sp. nov. and Gilvimarinus algae sp. nov., isolated from kelp seedlings

Two novel rod-shaped, strictly aerobic, non-motile and Gram-stain-negative bacterial strains, designated SDUM040013^T and SDUM040014^T, were isolated from kelp seedlings in Weihai, PR China. Cells of strain SDUM040013^T were 0.3-0.4 µm wide and 0.8-1.8 µm long, catalase-positive and oxidase-positive. Growth of SDUM040013^T was observed at 0-37 °C (optimum, 28-30 °C) and pH 5.5-9 (optimum, pH 8.0) and in the presence of 1-8 % (w/v) NaCl (optimum, 2 %). The DNA G+C content of strain SDUM040013^T was 50.5 %. Strain SDUM040013^T showed the highest 16S rRNA gene sequence similarity (97.1 %) to Gilvimarinus chinensis. Cells of strain SDUM040014^T were 0.4-0.5 µm wide and 1.0-1.4 µm long, catalase-positive and oxidase-positive. Growth of SDUM040014^T was observed at 4-40 °C (optimum, 28-30 °C) and pH 5.5-9 (optimum, pH 8.5) and in the presence of 0-8 % (w/v) NaCl (optimum, 2 %). The DNA G+C content of strain SDUM040014^T was 56.5 %. Strain SDUM040014^T showed the highest 16S rRNA gene sequence similarity (96.2%) to Gilvimarinus polysaccharolyticus. The isoprenoid quinone of both strains was Q-8 and the predominant fatty acids were summed feature 3 (C_16 : 1  ω7c and/or C_16 : 1  ω6c), summed feature 8 (C_18 : 1  ω7c) and C_16 : 0. Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were the major polar lipids. Given these phenotypic and chemotaxonomic properties, as well as phylogenetic data, strains SDUM040013^T and SDUM040014^T were considered to represent two novel species of the genus Gilvimarinus, for which the names Gilvimarinus gilvus sp. nov. and Gilvimarinus algae sp. nov. are proposed. The type strains are SDUM040013^T (=KCTC 8123^T=MCCC 1H01413^T) and SDUM040014^T (=KCTC 8124^T=MCCC 1H01414^T), respectively.