Kordiimonas aestuarii sp. nov., a marine bacterium isolated from a tidal flat

Abstract

A Gram-staining negative, strictly aerobic bacterium, designated 101-1(T), was isolated from a sea tidal flat, Taean, Korea. The strain formed small light-yellow, smooth, and circular colonies on marine agar. Cells were weakly halophilic, motile rods showing catalase- and oxidase-positive reactions. Growth of strain 101-1(T) was observed at 15-40 degrees C (optimum, 30 degrees C), pH 5.0-8.0 (optimum, pH 6.5-7.0) and 1.0-9.0% (w/v) NaCl (optimum, 2.0-3.5%). The G +C content of the genomic DNA was 53.3 mol%. Strain 101-1(T) contained ubiquinone-10 (Q-10) as the respiratory quinone and iso-C-17:1 omega 9C, iSO-C-15:0 and iso-C-17:0 as major fatty acids. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain 101-1(T) formed a tight phylogenetic lineage with members of the genus Kordiimonas and was most closely related to Kordiimonas gwangyangensis GW14-5(T) and Kordiimonas lacus S3-22(T) with 97.3% and 96.3% 16S rRNA gene sequence similarities, respectively. The DNA-DNA relatedness values between strain 101-1(T) and K gwangyangensis GW14-5(T) and K. lacus S3-22(T) were 24.8 +/- 4.4 % and 32.2 +/- 3.6%, respectively. Based on the data from the phenotypic and genotypic studies, strain 101-1(T) represents a novel species of the genus Kordiimonas, for which the name Kordiimonas aestuarii sp. nov. is proposed. The type strain is 101-1(T) (=KACC 16184(T) =JCM 17742(T)).