Kordiaulvae sp. nov., a bacterium isolated from the surface of green marine algae Ulva sp.

A novel bacterial strain, SC2, was isolated from Ulva sp., a green marine algae, which was collected from Dadeng island, Xiamen, China. Strain SC2 was Gram-stain-negative, aerobic, rod-shaped and had no flagellum. Oxidase and catalase were positive. Strain SC2was able to degrade skimmed milk, agar, soluble starch, Tween 20 and Tween 80 but not colloidal chitin. Growth was observed at salinities of 1-6 % and temperatures of 15-37 °C, with optimal salinity and temperature of 2 % and 30 °C, respectively. Phylogenetic analysis based on the 16S rRNA gene indicated that strain SC2 was affiliated to the genus Kordia, with highest sequence similarity to Kordia algicida OT-1 (97.23 %), Kordia antarctica IMCC 3317 (97.23 %) and Kordia jejudonensis SSK3-3 (97.02 %); the type strains of other species of the genus Kordia shared 93.98-95.78 % gene sequence similarity with strain SC2. The average nucleotide identity value and estimated DNA-DNA hybridization value between strain SC2 and the above three type strains (K. algicida OT-1, K. antarctica IMCC 3317 and K. jejudonensis SSK3-3) were found to be 79.4-82.4 % and 24.2-27.0 %, respectively. The predominant fatty acids (>5.0 %) were C16 : 0, iso-C15 : 0, iso-C15 : 0 3-OH, iso-C17 : 0 3-OH, summed feature 3 (comprising C16 : 1ω7c/C16 : 1ω6c), summed feature 8 (comprising C18 : 1ω7c/C18 : 1ω6c) and summed feature 9 (comprising iso-C17 : 1ω9c/C16 : 0 10-methyl). The respiratory quinone was determined to be solely menaquinone-6 (MK-6). The polar lipid profile of strain SC2 consisted of four unknown lipids, three unidentified phospholipids, one unidentified aminolipid and phosphatidylethanolamine. The G+C content of the genomic DNA was 34.5 mol%. The combined genotypic and phenotypic data showed that strain SC2 represents a novel species within the genus Kordia, for which the name Kordia ulvae sp. nov. is proposed. The type strain is SC2 (= KCTC 42872=MCCC 1A01772=LMG 29123).