Marinobacter halodurans sp. nov., a halophilic bacterium isolated from sediment of a salt flat

Abstract

A Gram-staining-negative, aerobic, cream-coloured, marine bacterium, with rod-shaped cells, designated strain YJ-S3-2^T, was isolated from salt flat sediment of Yongyu-do, Republic of Korea. YJ-S3-2^T grew at pH 5.0-9.0 (optimum pH 7.0), 4-45 °C (optimum 30 °C) and with 1-18 % (w/v) NaCl (optimum 6 %). The results of 16S rRNA gene sequence analysis indicated that YJ-S3-2^T was closely related to Marinobacter segnicrescens SS011B1-4^T (97.0 %) followed by, 'Marinobacter nanhaiticus' D15-8W (96.7 %), Marinobacter bryozoorum 50-11^T (96.7 %), Marinobacter koreensis DSMZ 179240^{T T} (96.5 %) and Marinobacter bohaiensis T17^T (96.5 %). The average nucleotide identity (ANI) and the genome to genome distance calculator (GGDC) estimate values between YJ-S3-2^T and related type strains were 73.7-79.8 and 19.9-22.5 %, and also 73.5 and 20.7 % with Marinobacter hydrocarbonoclasticus. YJ-S3-2^T was characterized as having Q-9 as the predominant respiratory quinone and the principal fatty acids (>10 %) were C_{16 : 0} (22.3 %), summed feature 9 (C_{17 : 1}iso ω9c/C_{16 : 0} 10-methyl, 13.8 %) and 3 (C_{16 : 1}ω7c/C1_{6 : 1}ω6c, 11.9 %). The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two unidentified aminolipids and two unidentified phospholipids. The DNA G+C content of YJ-S3-2^T is 60.9 mol%. On the basis of the polyphasic taxonomic evidence presented in this study, YJ-S3-2^T should be classified as representing a novel species within the genus Marinobacter, for which name Marinobacter halodurans sp. nov. is proposed, with the type strain YJ-S3-2^T (=KACC 19883^T=KCTC 62937^T=JCM 33109^T).

Keywords: Marinobacter; Proteobacteira; halophilic bacteria; salt flat.