Shimia sediminis sp. nov., a bacterium isolated from marine sediment in the East China Sea

Abstract

A Gram-stain-negative, ovoid-shaped, motile and strictly aerobic bacterium, designated ZQ172T, was isolated from marine sediment sampled on Zhoushan Island located in the East China Sea. Strain ZQ172T grew optimally at temperatures of 25–30 °C, at NaCl concentration of 2.0 % (w/v) and at pH 7.0–8.5. Catalase and oxidase activities, urease, and nitrate reduction were positive. Indole production, methyl red reaction, H2S production and hydrolysis of gelatin, starch, casein and Tweens 20, 40, 60 and 80 were negative. The major cellular fatty acid was summed feature 8 (C18 : 1  ω7c and/or C18 : 1  ω6c). The only respiratory quinone was ubiquinone-10. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidylcholine. Comparative analysis of the 16S rRNA gene sequence showed highest similarities to Shimia aestuarii JC2049T (97.5 %), Shimia abyssi JAMH 043T (97.5 %) and Shimia thalassica CECT 7735T (97.3 %). Phylogenetic analyses indicated that strain ZQ172T clustered with the genus Shimia and was closely related to Shimia thalassica CECT 7735T. The average nucleotide identity and digital DNA–DNA hybridization values between strain ZQ172T and related species of the genus Shimia were well below the threshold limit for prokaryotic species delineation. The DNA G+C content was 59.6 mol%. Based on its phenotypic, chemotaxonomic and genotypic data, strain ZQ172T is considered to be a representative of a novel species in the genus Shimia , for which the name Shimia sediminis sp. nov. is proposed. The type strain is ZQ172T (=KCTC 62578T=MCCC 1K03531T).