Niastella koreensis gen. nov., sp. nov. and Niastella yeongjuensis sp. nov., novel members of the phylum Bacteroidetes, isolated from soil cultivated with Korean ginseng.

Two novel strains, GR20-10(T) and GR20-13(T), were isolated from soil using R2A medium. The soil sample was collected from a field in the Yeongju region of Korea that was cultivated with Korean ginseng. Phylogenetic analysis based on 16S rRNA gene sequences indicated that these strains formed a cluster with several uncultured bacterial clones and with Flexibacter filiformis, Flexibacter sancti, Flexibacter japonensis, Cytophaga arvensicola and Flavobacterium ferrugineum (recently reclassified as Terrimonas ferruginea) in the phylum Bacteroidetes. The level of 16S rRNA gene sequence similarity between the two novel strains was 98.9 %. Isolates GR20-10(T) and GR20-13(T) showed the highest sequence similarities to Flexibacter japonensis IFO 16041(T) (91.8 and 91.9 %, respectively) and T. ferruginea ATCC 13524(T) (90.4 and 90.6 %, respectively). The whole-cell fatty acid profiles of the two isolates were similar and their major fatty acids were 15 : 0 iso, 17 : 0 iso 3-OH and 15 : 1 iso G. The major isoprenoid quinone of both strains was MK-7. The G+C contents of GR20-10(T) and GR20-13(T) were 45.8 and 44.3 mol%, respectively. DNA-DNA hybridization (57 % DNA-DNA hybridization value) and phenotypic data indicated that strains GR20-10(T) and GR20-13(T) each belong to a separate species. On the basis of phenotypic and phylogenetic data and genomic distinctiveness, strains GR20-10(T) and GR20-13(T) represent two novel species in a novel genus in the phylum Bacteroidetes; the names Niastella koreensis gen. nov., sp. nov. (the type species; type strain GR20-10(T)=KACC 11465(T)=DSM 17620(T)) and Niastella yeongjuensis sp. nov. (type strain GR20-13(T)=KACC 11466(T)=DSM 17621(T)) are proposed.

[1]  M. Okuhara,et al.  Flexibacter japonensis sp. nov., a New Species That Produces a Novel Inhibitor of Human Leukocyte Elastase Isolated from Soil , 1996, Current Microbiology.

[2]  L. Sly,et al.  Phylogenetic position of Chitinophaga pinensis in the Flexibacter-Bacteroides-Cytophaga phylum. , 1999, International journal of systematic bacteriology.

[3]  H. Reichenbach,et al.  A simple test for flexirubin-type pigments , 1980 .

[4]  W. Whitman,et al.  Precise Measurement of the G+C Content of Deoxyribonucleic Acid by High-Performance Liquid Chromatography , 1989 .

[5]  Erko Stackebrandt,et al.  Taxonomic Note: A Place for DNA-DNA Reassociation and 16S rRNA Sequence Analysis in the Present Species Definition in Bacteriology , 1994 .

[6]  Makoto Suzuki,et al.  Phylogenetic structure of the genera Flexibacter, Flexithrix, and Microscilla deduced from 16S rRNA sequence analysis. , 2002, The Journal of general and applied microbiology.

[7]  J. Breznak,et al.  Physicochemical Factors in Growth , 2007 .

[8]  A. Yokota,et al.  Reclassification of [Flavobacterium] ferrugineum as Terrimonas ferruginea gen. nov., comb. nov., and description of Terrimonas lutea sp. nov., isolated from soil. , 2006, International journal of systematic and evolutionary microbiology.

[9]  Y. Nakagawa,et al.  Phylogenetic diversity of the genus Cytophaga revealed by 16S rRNA sequencing and menaquinone analysis. , 1993, Journal of general microbiology.

[10]  A. Hiraishi,et al.  Direct automated sequencing of 16S rDNA amplified by polymerase chain reaction from bacterial cultures without DNA purification , 1992, Letters in applied microbiology.

[11]  S. Lapage,et al.  Biochemical Tests for Identification of Medical Bacteria , 1976 .

[12]  V. Skerman,et al.  Chitinophaga, a New Genus of Chitinolytic Myxobacteria , 1981 .

[13]  D. Dubnau,et al.  Deoxyribonucleic Acid Homology Among Bacillus polymyxa, Bacillus macerans, Bacillus azotofixans, and Other Nitrogen-Fixing Bacillus Strains , 1985 .

[14]  M. Fegan,et al.  Phylogenetic heterogeneity within the genus Herpetosiphon: transfer of the marine species Herpetosiphon cohaerens, Herpetosiphon nigricans and Herpetosiphon persicus to the genus Lewinella gen. nov. in the Flexibacter-Bacteroides-Cytophaga phylum. , 1998, International journal of systematic bacteriology.

[15]  J. Schimel,et al.  Comparison of subsurface and surface soil bacterial communities in california grassland as assessed by terminal restriction fragment length polymorphisms of PCR-amplified 16S rRNA genes , 2003, Microbial Ecology.

[16]  F. Rainey,et al.  Agrococcus jenensis gen. nov., sp. nov., a new genus of actinomycetes with diaminobutyric acid in the cell wall. , 1996, International journal of systematic bacteriology.

[17]  Mac Faddin,et al.  Biochemical tests for identification of medical bacteria , 1976 .

[18]  Sudhir Kumar,et al.  MEGA3: Integrated software for Molecular Evolutionary Genetics Analysis and sequence alignment , 2004, Briefings Bioinform..

[19]  P. Vandamme,et al.  Cutting a gordian knot: Emended classification and description of the genus Flavobacterium, emended description of the family Flavobacteriaceae, and proposal of Flavobacterium hydatis nom nov (basonym, Cytophaga aquatilis Strohl and Tait 1978). , 1996 .

[20]  Peter Vandamme,et al.  New perspectives in the classification of the flavobacteria: description of Chryseobacterium gen. nov., Bergeyella gen-nov, and Empedobacter nom-rev. , 1994 .

[21]  Sang-Hong Yoon,et al.  Pseudomonas koreensis sp. nov., Pseudomonas umsongensis sp. nov. and Pseudomonas jinjuensis sp. nov., novel species from farm soils in Korea. , 2003, International journal of systematic and evolutionary microbiology.