Olsenella scatoligenes sp nov., a 3-methylindole- (skatole) and 4-methylphenol- (p-cresol) producing bacterium isolated from pig faeces

Strain SK9K4(T), which is a strictly anaerobic, non-motile, non-sporulating, Gram-stain-positive, saccharolytic coccobacillus, was isolated from pig faeces. SK9K4(T) metabolized indol-3-acetic acid to 3-methylindole (skatole), which is the main contributor to boar taint; it also produced 4-methylphenol (p-cresol) from p-hydroxyphenylacetic acid. Phylogenetic analyses, based on 16S rRNA gene sequences, revealed that the isolate represented a new lineage within the genus Olsenella of the family Atopobiaceae. Strain SK9K4(T) was most closely related to the type strains of the three species of the genus Olsenella with validly published names; Olsenella pro fusa DSM 13989(T) (93.6%), Olsenella uli DSM 7084(T) (93.5%) and Olsenella umbonata DSM 22620(T) (92.7%). DNA-DNA relatedness values of strain SK9K4(T) with O. pro fusa, O. uli and O. umbonata were 28.3%, 69.1% and 27.2%, respectively. The genomic DNA G+C content was 62.1 mol% and the major cellular fatty acids (constituting >10% of the total) were C-14:0 and C-18:1 omega 9c. The major end product of glucose fermentation was lactic acid, with minor amounts of acetic acid and formic acid; no H-2 was produced. Discrepancies in the fatty acid profiles, the MALDI-TOF mass spectra of cell extracts and the physiological and biochemical characteristics differentiated strain SK9K4(T) from other species of the genus Olsenella and indicate that the isolate represents a novel species within this genus. The name Olsenella scatoligenes sp. nov., is proposed and the type strain is SK9K4(T) (=JCM 19907(T)=DSM 28304(T)).