Title Characterization of Flavobacterium aquimarinum sp. nov., a halotolerant bacterium isolated from seawater
Author Sylvia Kristyanto1, Tuan Manh Nguyen1,2, Dhiraj Kumar Chaudhary1, Sang-Seob Lee1, and Jaisoo Kim1*
Address 1Department of Life Science, College of Natural Sciences and Engineering, Kyonggi University, Suwon 16227, Republic of Korea, 2Thai Nguyen University of Agriculture and Forestry, Quyet Thang, Thai Nguyen, Vietnam
Bibliography Journal of Microbiology, 56(5),317–323, 2018,
DOI 10.1007/s12275-018-7454-3
Key Words Flavobacterium aquimarinum sp. nov., seawater, halotolerant, Flavobacteriaceae, bacteroidetes
Abstract A novel, aerobic, Gram-stain-negative, non-motile, non-spore forming, rod-shaped bacterium, designated strain Dol 15-39T, was isolated from a seawater sample near Geoje Island in the South Sea, Republic of Korea. The strain was found to be oxidase-negative and catalase-positive. The isolate was observed to grow at temperatures from 4 to 37°C, at salinities of up to 7%, and at pH levels from 6 to 9; moreover, it was not able to degrade starch, DNA, esculin, or tyrosine. Phylogenetic analysis based on 16S rRNA gene sequences showed that Dol 15-39T was most closely related to Flavobacterium jumunjinense HME7102T with a sequence similarity of 97.3%. However, the levels of DNA-DNA relatedness between Dol 15-39T and the most closely related species were much lower than 70%, confirming that they represented distinct genomic species. The genomic DNA G + C content of Dol 15-39T was calculated to be 32.6 mol%. MK-6 was the predominant respiratory quinine, while iso-C15:0 (25.0%), iso- C15:1 G (17.0%), and iso-C17:0 3-OH (10.4%) were the major cellular fatty acids. Phosphatidylethanolamine was identified as a major polar lipid, while various unidentified aminolipids and polar lipids were also detected. Based on polyphasic taxonomic data, Dol 15-39T represents a novel species of the genus Flavobacterium, for which the name F. aquimarinum sp. nov. is proposed. The type strain is accessible under the culture collection numbers (KEMB 9005-617T = JCM 31930T).