Maribacter luteus sp. nov., a marine bacterium isolated from intertidal sand of the Yellow Sea

A novel rod-shaped and Gram-stain-negative bacterium, designated strain RZ05^T, was isolated from a sand sample collected from the intertidal zone of the Yellow Sea, PR China. Results of phylogenetic analysis based on 16S rRNA gene sequences revealed that strain RZ05^T clusters within the genus Maribacter, a member of the family Flavobacteriaceae, and has the highest sequence similarity to Maribacter polysiphoniae KCTC 22021^T (97.8 %), followed by Maribacter arenosus KCTC 52191^T (97.2 %). Cells of this strain were observed to be aerobic, oxidase- and catalase-positive, motile by gliding and formed yellow colonies. Growth occurred at 7-40 °C (optimum, 30 °C), at pH 6.5-9.5 (optimum, pH 7.0) and with 0.5-6 % (optimum, 2 %) NaCl. Its polar lipid profile included phosphatidylethanolamine, two unidentified glycolipids, one unidentified aminolipid and four unidentified lipids. The major cellular fatty acids were iso-C_15 : 0, iso-C_15 : 1 G, iso-C_17 : 0 3-OH, iso-C_16 : 0 3-OH, iso-C_15 : 0 3-OH, summed feature 9 (10-methyl C_16 : 0/iso-C_17 : 1  ω9c) and summed feature 3 (iso-C_15 : 0 2-OH/C_16 : 1  ω7c/C_16 : 1  ω6c). The only respiratory quinone was menaquinone 6 (MK-6). The genome of strain RZ05^T was 4.65 Mbp with a G+C content of 38.9 mol%. The average nucleotide identity and in silico DNA-DNA hybridization values between strain RZ05^T and its most closely related type strain M. polysiphoniae KCTC 22021^T were 80.3 and 26.3  %, respectively. The results of phylogenetic, phenotypic and chemotaxonomic analyses indicated that strain RZ05^T represents a novel species of the genus Maribacter, for which the name Maribacter luteus sp. nov. is proposed. The type strain is RZ05^T (=KCTC 62834^T=MCCC 1K03617^T).