Pseudopropionibacterium rubrum sp nov., a novel red-pigmented species isolated from human gingival sulcus

In this study, sStrain SK-1(T), a novel gram-positive, pleomorphic, rod-shaped, non-spore forming, non-motile organism, designated SK-1(T), was isolated from human gingival sulcus and found to produce acetic acid, propionic acid, lactic acid, and succinic acid as end products of glucose fermentation. Strain SK-1(T) is most closely related to Pseudopropionibacterium (Propionibacterium) propionicum with sequence homologies of the 16S rRNA and RNA polymerase subunit (rpoB) genes of 96.6% and 93.1%, respectively. The genomic DNA G+C content of the isolate was 61.8 mol%. On the basis of the sequence data of the 16S rRNA and housekeeping (rpoB) genes, a novel taxon is here proposed, Pseudopropionibacterium rubrum sp. nov. (type strain SK-1(T)=JCM 31317(T)=DSM 100122(T)). The 16S rRNA and rpoB gene sequences of strain SK-1(T) have been deposited in the DDBJ under the accession numbers LC002971 and LC102236, respectively.