Flavobacterium inviolabile sp. nov. isolated from stream water

Abstract

A Gram-stain-negative, rod-shaped, aerobic and non-motile bacterium, designated P2-65^T, was isolated from Moonsan stream water in the Republic of Korea. The temperature, NaCl concentration and pH ranges for growth of strain P2-65^T were 10-37 °C, 0.0-3.0% (w/v) and 6.5-8.5 with optimum growth at 25-30 °C, 0.0-1.0% and 7.0-7.5, respectively. Comparison of 16S rRNA gene sequence showed that strain P2-65^T was closely related to Flavobacterium cauense (95.4%) and Flavobacterium cheniae (95.3%). The major fatty acids were iso-C_15:0, iso C_17:0 3-OH, summed feature 3 (C_16:1ω7c and/or C_16:1ω6c), summed feature 9 (iso-C_17:1 ω9c and/or 10-methyl C_16:0) and iso-C_15:0 3-OH. The predominant respiratory quinone was menaquinone-6 (MK-6). The major polar lipids detected in the strain were phosphatidylethanolamine, one aminophospholipid, one unidentified aminolipid and one unidentified polar lipid. The G + C content of the genomic DNA was 39.7%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values for strain P2-65^T with closely related Flavobacterium species were below 74.8% and 20%, respectively. Based on polyphasic features, strain P2-65^T is considered to represent a novel species of the genus Flavobacterium, for which the name Flavobacterium inviolabile sp. nov. is proposed. The type strain is P2-65^T (= KCTC 62055^T = NBRC 112953^T).

Keywords: Flavobacteriaceae; Flavobacterium inviolabile; Polyphasic taxonomy; Stream water.