Pseudidiomarina sediminum sp. nov., a marine bacterium isolated from coastal sediments of Luoyuan Bay in China

Abstract

A strain of heterotrophic, facultatively anaerobic, marine bacterium, designated strain c121T, was isolated from coastal sediment of Luoyuan Bay, in Fujian province, PR China. Analysis of the 16S rRNA gene sequence revealed an affiliation with the genus Pseudidiomarina; the sequence similarity between c121T and Pseudidiomarina taiwanensis PIT1T was 97%. Cells of the novel strain were non-pigmented, Gram-negative rods, 0.3 microm wide and 1.2-1.8 microm long. Cells grown in broth cultures were non-motile, lacking flagella. Growth of the strain was observed at salinities ranging from 0.5 to 15 % NaCl, and the optimal concentration was about 1-8%. The temperature range for growth was rather broad and was high for a marine bacterium: the strain grew at 13-42 degrees C, showed good growth at 20-40 degrees C and had an optimum between 30 and 40 degrees C. The major cellular fatty acids were iso-C15:0 (24.2%), C16:1omega7c/iso-C15:0 2-OH (15.3%) and iso-C17:1omega9c (11.9%). The DNA G+C content was 50.0 mol%. Phylogeny based on 16S rRNA gene sequences, together with data from phenotypic and chemotaxonomic characterization, revealed that strain c121T could be classified within a novel species of the genus Pseudidiomarina, for which the name Pseudidiomarina sediminum sp. nov. is proposed, with the type strain c121T (=CICC 10319T=LMG 24046T).