Marinomonas shanghaiensis sp. nov., isolated from the junction between an ocean and a freshwater lake.

Abstract

A Gram-stain-negative, motile with single polar flagellum, rod-shaped bacterium, designated as strain DSL-35T, was isolated from the location where the ocean and Dishui lake meet at Shanghai on the East China Sea and characterized phylogenetically and phenotypically. Optimal growth occurred at 35 °C (range, 4-40 °C), pH 8 pH 5-11) and with 3-4 % (w/v) NaCl (0-12 %). Phylogenetic analysis based on its 16S rRNA gene sequence showed that strain DSL-35T was related to members of the genus Marinomonas and shared the highest sequence identities with Marinomonasarctica 328T (98.0 %), Marinomonashwangdonensis HDW-15T (97.5 %) and Marinomonasrhizomae IVIA-Po-145T (97.2 %). The 16S rRNA gene sequence identities between strain DSL-35T and other members of the genus Marinomonas were below 96.8 %. The digital DNA-DNA hybridization values between strain DSL-35T and the three type strains, Marinomonas. arctica 328T, M. rhizomae HDW-15T and M. rhizomae IVIA-Po-145T, were 30.9±2.4 %, 21.7±2.2% and 22±2.3 %, respectively. The average nucleotide identity values between strain DSL-35T and the three type strains were 87.6 %, 84.6 and 84.2 %, respectively. The predominant ubiquinone was Q-8. The major polar lipids were phosphatidylethanolamine and phosphatidylglycerol. The predominant cellular fatty acids of strain DSL-35T were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 40.0 %), C16 : 0 (22.5 %), summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c; 11.2 %), summed feature 2 (C14 : 0 3-OH and/or iso I C16 : 1; 7.2 %), C14 : 0 (6.8 %) and C12 : 0 (5.2 %). The G+C content of the genomic DNA was 44.5 mol%. The combined genotypic and phenotypic data indicated that strain DSL-35T represents a novel species of the genus Marinomonas, for which the name Marinomonas shanghaiensis sp. nov. is proposed, with the type strain DSL-35T (=KCTC 62646T=MCCC 1K03535T).