Opitutus terrae gen nov, sp nov, to accommodate novel strains of the division 'Verrucomicrobia' isolated from rice paddy soil

Three strains of obligately anaerobic bacteria were isolated from rice padd y soil microcosms. Comparative analysis of the 16S rRNA genes showed that t hese novel isolates have identical gene sequences and are members of the di vision 'Verrucomicrobia'. The novel strains are phenotypically and phylogen etically distinct from species described previously. One strain, PB90-1(T), was characterized in more detail. The cells are cocci and are motile by me ans of a flagellum. Catalase and oxidase activities are absent. Growth-supp orting substrates include mono-, di- and polysaccharides, while alcohols, a mino acids and organic acids do not support growth. Propionate and acetate are the major end-products of fermentation. Nitrate is reduced to nitrite, but other external electron acceptors are not utilized. The G+C content of the genomic DNA is 74 mol%. This strain represents a taxon that has not yet been formally recognized, for which the name Opitutus terrae gem. nov., sp . nov. is proposed. The type strain is PB90-1(T) (= DSM 11246(T)).