Microbulbifer flavimaris sp. nov., a halophilic Gammaproteobacteria isolated from marine sediment of the Yellow Sea, China.

A Gram-stain-negative, aerobic, non-flagellated, non-motile bacterium, designated strain WRN-8, was isolated from marine sediment of the Yellow Sea, China (36° 5' 33'' N, 121° 20' 37'' E). Colonies of strain WRN-8 were 0.2-0.3 µm wide, 2.1-2.8 µm long, catalase-positive and oxidase-positive. Colonies on marine agar solid media were circular, wet, smooth, light yellow and approximately 1.3 mm in diameter. Growth occurred optimally at 33-37 °C, pH 7.0-7.5 and in the presence of 2-4 % NaCl (w/v). Phylogenetic analysis of the 16S rRNA gene indicated that strain WRN-8 is a member of the genus Microbulbifer within the family Microbulbiferaceae, and the closest described neighbour in terms of 16S rRNA gene sequence identity is Microbulbifer aestuariivivens KCTC 52569 (98.1 %). The major respiratory quinone of strain WRN-8 is Q-8, its predominant fatty acids are iso-C15 : 0, iso-C17 : 0, C16 : 0, iso-C11 : 03-OH and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), and its major polar lipids are phosphatidylethanolamine, phosphatidylglycerol, glycolipid, an unidentified phospholipid and an unidentified lipid. The draft genome obtained in this study was 3 643 020 bp, and the G+C content was 59.2 mol%. DNA-DNA hybridization (<46.3 %) and average nucleotide identity (<86.7 %) values between strain WRN-8 and the closest-related recognized Microbulbifer species confirmed the novelty of this new species. Therefore, we propose a novel species in the genus Microbulbifer to accommodate the novel isolate: Microbulbifer flavimaris sp. nov. (type strain WRN-8=KCTC 42989=ACCC 19926).