Two novel strains belonging to the phylum Bacteroidetes [formerly the Cytophaga–Flexibacter–Bacteroides (CFB) group], designated Gsoil 040T and Gsoil 052T, were isolated from the soil of a ginseng field in Pocheon province, South Korea. A polyphasic approach was used to characterize the taxonomic position of the novel strains. Both strains were Gram-negative, aerobic, non-motile, non-spore-forming and rod-shaped. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the novel isolates belong to the genus Chitinophaga but are clearly separated from the recognized species of this genus; gene sequence similarities between the novel isolates and type strains of recognized species ranged from 91.2 to 96.5 %. One exception was found; strain Gsoil 052T and the type strain of Chitinophaga filiformis had a gene sequence similarity of 99.6 % but had a DNA–DNA relatedness value of 38 %. Phenotypic and chemotaxonomic data (major menaquinone, MK-7; major fatty acids, iso-C15 : 0 and C16 : 1 ω5c; major hydroxy fatty acid, iso-C17 : 0 3-OH and major polyamine, homospermidine) supported the affiliation of both strains Gsoil 040T and Gsoil 052T to the genus Chitinophaga. The results of physiological and biochemical tests enabled the genotypic and phenotypic differentiation of the novel strains from the other recognized species of the genus Chitinophaga. Therefore, it is suggested that the new isolates represent two novel species, for which the names Chitinophaga ginsengisegetis sp. nov. [type strain Gsoil 040T (=KCTC 12654T=DSM 18108T)] and Chitinophaga ginsengisoli sp. nov. [type strain Gsoil 052T (=KCTC 12592T=DSM 18017T)] are proposed.
A strictly anaerobic cellulolytic bacterium, strain CRE21T, was isolated from a human faecal sample. Cells were Gram-negative non-motile rods that were about 1.7 μm in length and 0.9 μm in width. Strain CRE21T degraded different types of cellulose and was able to grow on a variety of carbohydrates. Cellulose and sugars were mainly converted to acetate, propionate and succinate. The G+C content of the DNA was 41.1 mol%. 16S rRNA gene sequence analysis revealed that the isolate belonged to the genus Bacteroides with highest sequence similarity to the type strain of Bacteroides intestinalis (98 %). DNA–DNA hybridization results revealed that strain CRE21T was distinct from B. intestinalis (40 % DNA–DNA relatedness). Strain CRE21T also showed several characteristics distinct from B. intestinalis. In particular, it exhibited different capacity to degrade polysaccharides such as cellulose. On the basis of phylogenetic analysis and the morphological, physiological and biochemical data presented in this study, strain CRE21T can be readily differentiated from recognized species of the genus Bacteroides. The name Bacteroides cellulosilyticus sp. nov. is proposed to accommodate this organism. The type strain is CRE21T (=DSM 14838T=CCUG 44979T).
A bacterial strain, DC-186T, isolated from home-made compost, was characterized for its phenotypic and phylogenetic properties. The isolate was a Gram-negative rod that was able to grow at 15–36 °C and pH 5.5–8.0. Strain DC-186T was positive in tests for catalase, oxidase and β-galactosidase activities and aesculin hydrolysis. The predominant fatty acids were the summed feature C16 : 1/iso-C15 : 0 2-OH (42 %) and iso-C15 : 0 (26 %), the major respiratory quinone was menaquinone-7 and the genomic DNA G+C content was 42 mol%. 16S rRNA gene sequence analysis and phenetic characterization indicated that this organism belongs to the phylum Bacteroidetes and revealed its affiliation to the family Sphingobacteriaceae. Of recognized taxa, strain DC-186T was most closely related to Sphingobacterium daejeonense (90 % sequence similarity) based on 16S rRNA gene sequence analysis. The low 16S rRNA gene sequence similarity with other recognized taxa and the identification of distinctive phenetic features for this isolate support the definition of a new genus within the family Sphingobacteriaceae. The name Pseudosphingobacterium domesticum gen. nov., sp. nov. is proposed, with strain DC-186T (=CCUG 54353T=LMG 23837T) as the type strain.
A Gram-negative, strictly aerobic, short rod-shaped, non-motile bacterial strain designated 4M24T was isolated from cotton-waste compost. Analysis of the 16S rRNA gene sequence of strain 4M24T revealed that it is a member of the genus Sphingobacterium, sharing 88.5–94.5 % sequence similarity with type strains of the genus Sphingobacterium and being most closely related to Sphingobacterium daejeonense TR6-04T (94.5 % sequence similarity) and Sphingobacterium mizutaii ATCC 33299T (92.2 % similarity). The major fatty acids of strain 4M24T grown on trypticase soy agar medium were summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1 ω7c; 37.5 %), iso-C15 : 0 (29.5 %) and iso-C17 : 0 3-OH (19.7 %). The G+C content of the genomic DNA was 42.3 mol%. On the basis of phenotypic and genotypic characteristics, strain 4M24T represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium composti sp. nov. is proposed. The type strain is 4M24T (=KACC 11313T=DSM 18850T).
Two bacterial strains, R2A1-13T and R2A45-3T, were isolated from greenhouse soils in Korea. The cells of both strains were Gram-negative, aerobic and rod-shaped. 16S rRNA gene sequence analysis placed the isolates in the genus Flavobacterium within the family Flavobacteriaceae. Strain R2A1-13T was found to be related to Flavobacterium columnare IAM 14301T, Flavobacterium saliperosum CGMCC1.3801T and Flavobacterium croceum EMB47T, with sequence similarities of 96.8, 95.0 and 94.6 %, respectively. Strain R2A45-3T was found to be related to F. croceum EMB47T and Flavobacterium aquatile ATCC 11947T, with sequence similarities of 94.7 and 94.6 %, respectively. Both strains contained iso-C15 : 0 and iso-C16 : 0 as the main fatty acids and contained a menaquinone with six isoprene units (MK-6) as the major isoprenoid quinone. The G+C contents of the DNA from strains R2A1-13T and R2A45-3T were 34 and 38 mol%, respectively. A polyphasic taxonomic study revealed that these strains belong to two novel species within the genus Flavobacterium, for which the names Flavobacterium terrae sp. nov. and Flavobacterium cucumis sp. nov. are proposed. The type strains of F. terrae sp. nov. and F. cucumis sp. nov. are R2A1-13T (=KACC 11731T=DSM 18829T) and R2A45-3T (=KACC 11732T=DSM 18830T), respectively.