Prevotella shahii sp. nov. and Prevotella salivae sp. nov., isolated from the human oral cavity

Abstract

Two bacterial strains, EHS11T and EPSA11T, which were isolated from the human oral cavity, were characterized in terms of phenotypic and biochemical characteristics, cellular fatty acid profiles and phylogenetic position based on 16S rRNA gene sequence analysis. 16S rRNA gene sequence analysis showed that each of the isolates belonged to a novel species of the genus Prevotella. Strain EHS11T was related to Prevotella loescheii (about 95 % similarity), whereas strain EPSA11T was related to Prevotella oris (about 94 % similarity). Both strains were obligately anaerobic, non-pigmented, non-spore-forming, non-motile, Gram-negative rods. The cellular fatty acid composition of strain EPSA11T was very similar to that of P. oris JCM 8540T. On the other hand, the cellular fatty acid composition of strain EHS11T was significantly different from those of other Prevotella species. The predominant fatty acids in strain EHS11T are C18 : 1 ω9c, C16 : 0 and C16 : 0 3-OH, whereas other Prevotella species, except for P. loescheii JCM 8530T, possess anteiso-C15 : 0, iso-C17 : 0 3-OH and C18 : 1 ω9c. The predominant fatty acids in P. loescheii JCM 8530T are anteiso-C15 : 0, C16 : 0 and C18 : 1 ω9c. DNA–DNA hybridization experiments revealed a genomic distinction of strains EHS11T and EPSA11T from P. loescheii JCM 8530T and P. oris JCM 8540T. On the basis of these data, two novel Prevotella species are proposed: Prevotella shahii sp. nov. and Prevotella salivae sp. nov. The type strains of P. shahii and P. salivae are EHS11T (=JCM 12083T=DSM 15611T) and EPSA11T (=JCM 12084T=DSM 15606T), respectively.