Flavobacterium nackdongense sp. nov., a cellulose-degrading bacterium isolated from sediment.

A Gram-negative, non-motile, rod-shaped bacterial strain, designated GS13, was isolated from sediments in a branch of the Nackdong River in Sangju, Korea. Optimal growth occurred at pH 7.0, 20 °C, and 0% NaCl. Phylogenetic analyses using 16S rRNA showed that strain GS13 is a member of the genus Flavobacterium, with highest similarity to Flavobacterium soyangense IMCC26223 (97.0%). The DNA G+C content of strain GS13 was 36.2 mol%. The dominant fatty acids were summed feature 3 (Cω7c and/or Cω6c) and iso-C. The major polar lipids were phosphatidylethanolamine, three unidentified aminolipids, three unidentified lipids, and one unidentified aminophospholipid. The predominant respiratory quinone was MK-6. Our data demonstrate that strain GS13 can be distinguished from closely-related Flavobacterium species. Thus, strain GS13 is a novel Flavobacterium species, and we propose the name Flavobacterium nackdongense sp. nov. The type strain is GS13 (=KCTC 62569 = JCM 32765).