A novel rod-shaped and Gram-stain-negative bacterium, designated strain RZ05T, 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 RZ05T clusters within the genus Maribacter, a member of the family Flavobacteriaceae, and has the highest sequence similarity to Maribacter polysiphoniae KCTC 22021T (97.8 %), followed by Maribacter arenosus KCTC 52191T (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-C15 : 0, iso-C15 : 1 G, iso-C17 : 0 3-OH, iso-C16 : 0 3-OH, iso-C15 : 0 3-OH, summed feature 9 (10-methyl C16 : 0/iso-C17 : 1 ω9c) and summed feature 3 (iso-C15 : 0 2-OH/C16 : 1 ω7c/C16 : 1 ω6c). The only respiratory quinone was menaquinone 6 (MK-6). The genome of strain RZ05T 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 RZ05T and its most closely related type strain M. polysiphoniae KCTC 22021T were 80.3 and 26.3 %, respectively. The results of phylogenetic, phenotypic and chemotaxonomic analyses indicated that strain RZ05T represents a novel species of the genus Maribacter, for which the name Maribacter luteus sp. nov. is proposed. The type strain is RZ05T (=KCTC 62834T=MCCC 1K03617T).
Keywords: Flavobacteriaceae; Maribacter luteus sp. nov.; bacteroidetes; intertidal sand.