Marinomonas Profundi Sp. Nov., Isolated From Deep Seawater Of The Mariana Trench

A Gram-stain-negative, aerobic, polarly flagellated, straight or curved rod-shaped bacterium, designated strain M1K-6(T), was isolated from deep seawater samples collected from the Mariana Trench. The strain grew at -4 to 37 degrees C (optimum, 25-30 degrees C), at pH 5.5-10.0 (optimum, pH 7.0) and with 0.5-14.0 % (w/v) NaCl (optimum, 2.0%). It did not reduce nitrate to nitrite nor hydrolyse gelatin or starch. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain M1K-6(T) was affiliated with the genus Marinomonas, sharing 93.1-97.0% sequence similarity with the type strains of recognized Marinomonas species. The major cellular fatty acids were summed feature 3 (C-16:1 omega 6c/C-16:1 omega 7c), summed feature 8 (C-18:1 omega 7c/C-18:1 omega 6c), C-16:0, C-10:0 3-OH and C-18:0. The predominant respiratory quinone was ubiquinone-8. Polar lipids of strain M1K-6(T) included phosphatidylethanolamine, phosphatidylglycerol and two unidentified lipids. The genomic G+C content of strain M1K-6(T) was 46.0 mol%. Based on data from the present polyphasic study, strain M1K-6(T) was considered to represent a novel species within the genus Marinomonas, for which the name Marinomonas profundi sp. nov. is proposed. The type strain is M1K-6(T) (=KCTC 72501(T)=MCCC 1K03890(T)).