Description of Deefgea piscis sp. nov., and Deefgea tanakiae sp. nov., isolated from the gut of Korean indigenous fish.

Three novel strains, (D17T, D13, and D25T) isolated from the gut of the Korean dark sleeper (Odontobutis platycephala), Kumgang fat minnow (Rhynchocypris kumgangensis), and the Korean oily bitterling (Tanakia koreensis) were identified as two novel species. Strains D17T and D13 showed the highest similarities in 16S rRNA gene and complete genome sequences to Deefgea rivuli WB 3.4-79T (98.0% and 97.9%, respectively, of 16S rRNA gene sequence similarity, 77.8% and 77.7%, respectively, of orthologous average nucleotide identity, OrthoANI, and 21.9% and 21.9%, respectively, of digital DNA-DNA hybridization, dDDH). Strain D17T showed the highest similarities in 16S rRNA gene and complete genome sequences to D13 (99.9% of 16S rRNA gene sequence similarity, 91.8% of OrthoANI, and 45.1% of dDDH); therefore, strains D17T and D13 were assigned as the same species. Strain D25T showed the highest similarities in 16S rRNA gene and complete genome sequences to D. chitinilytica Nsw-4T (98.2% of 16S rRNA gene sequence similarity, 82.4% of OrthoANI, and 25.1% of dDDH). Strains D17T and D13 were Gram-stain-negative, facultative anaerobes, rod-shaped, non-motile, and non-flagellated. Strain D25T was Gram-stain-negative, facultative anaerobe, rod-shaped, and motile by a single polar flagellum. These strains had C16:0 and summed feature 3 (C16:1ω7c and/or C16:1ω6c) as the major cellular fatty acids and possessed Q-8 as a major respiratory ubiquinone. All three strains contained phosphatidylethanolamine and phosphatidylglycerol as the major polar lipids. Based on polyphasic taxonomic data, strains D17T, D13, and D25T represent two novel species of the genus Deefgea. We propose the name Deefgea piscis sp. nov. for strains D17T (= KCTC 82958T = JCM 34941T) and D13 (= KCTC 92368), and Deefgea tanakiae sp. nov. for strain D25T (= KCTC 82959T = JCM 34942T).

Description of Flavobacterium cyclinae sp. nov. and Flavobacterium channae sp. nov., isolated from the intestines of Cyclina sinensis (Corb shell) and Channa argus (Northern snakehead).

Two novel bacterial strains, KSM-R2A25T and KSM-R2A30T, were isolated from intestines of Cyclina sinensis (corb shell) and Channa argus (northern snakehead), respectively. Both specimens were collected in Korea. The strains were Gramstain-negative, non-motile, and strictly aerobic. According to phylogenetic analyses based on 16S rRNA gene sequences, strains belonged to the genus Flavobacterium within the family Flavobacteriaceae. 16S rRNA gene sequences of strains KSM-R2A25T and KSM-R2A30T were closely related to Flavobacterium cucumis DSM 18830T and Flavobacterium aquaticum JC164T with sequence similarities of 97.77% and 98.54%, respectively. Further genomic analyses including reconstruction of the UBCG tree and overall genome-related indices suggested them as novel species of the genus Flavobacterium. Both strains contained menaquinone with six isoprene units (MK-6) as a major isoprenoid quinone and iso-C15:1 G, iso-C15:0 and iso-C16:0 as major cellular fatty acids. The major polar lipid in both strains was phosphatidylethanolamine. The genomic G + C contents of strains KSM-R2A25T and KSM-R2A30T were 31.7 and 31.9%, respectively. Based on the polyphasic taxonomic study presented here, strains KSM-R2A25T and KSM-R2A30T represent novel species of the genus Flavobacterium, for which the names Flavobacterium cyclinae sp. nov and Flavobacterium channae sp. nov are proposed. The type strains of F. cyclinae sp. nov and F. channae sp. nov are KSM-R2A25T (= KCTC 82978T = JCM 34997T) and KSM-R2A30T (= KCTC 82979T = JCM 34998T), respectively.