Oribacterium parvum sp nov and Oribacterium asaccharolyticum sp nov., obligately anaerobic bacteria from the human oral cavity, and emended description of the genus Oribacterium

International Journal of Systematic and Evolutionary Microbiology (Impact Factor: 2.51). 05/2014; 64(Pt 8). DOI: 10.1099/ijs.0.060988-0
Source: PubMed


Three strictly anaerobic Gram-positive non-spore-forming rod-shaped motile bacteria designated as Oribacterium sp. ACB1T, ACB7T and ACB8 were isolated from the human subgingival dental plaque. All strains required yeast extract for growth. Strains ACB1T and ACB8 were able to grow on glucose, lactose, maltose, maltodextrin, and raffinose; strain ACB7T grew weakly on sucrose only. The growth temperature range was 30 - 42 oC with optimum at 37 oC. Major metabolic fermentation end products of strain ACB1T were acetate and lactate; the only product of strains ACB7T and ACB8 was acetate. Major fatty acids of strain ACB1T were C14:0, C16:0, C16:1 ω7c DMA (dimethyl aldehyde) and C18:1 ω7c DMA. Major fatty acids of strain ACB7T were C12:0, C14:0, C16:0, C16:1 ω7c and C16:1 ω7c DMA. The hydrolysate of peptidoglycan contained meso-diaminopimelic acid indicating peptidoglycan type A1γ. Genomic DNA G + C content varied from 42 to 43.3% between strains. According to 16S rRNA gene sequence phylogeny, strains ACB1T, ACB8 and ACB7T formed two separate branches within the genus Oribacterium, with sequence similarity to type species of Oribacterium sinus at 98.1-98.6%. Predicted DNA-DNA hybridization values between strains ACB1T, ACB8, ACB7T and O. sinus were <70%. Based on distinct genotypic and phenotypic characteristics, we suggest that strains ACB1T and ACB8, and strain ACB7T represent two distinct species of the genus Oribacterium, for which the names Oribacterium parvum sp. nov. and Oribacterium asaccharolyticum sp. nov. are proposed. The type strains are strain ACB1T (= DSM 24637T; = HM-481T; =ATCC BAA-2638T) and strain ACB7T (= DSM 24638T; = HM-482T; =ATCC BAA-2639T).

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Available from: Nicolai S Panikov, May 18, 2014