Ornithinibacillus contaminans sp. nov., an endospore-forming species

Abstract

A Gram-stain-positive, endospore-forming rod, designated CCUG 53201T, was isolated from a human blood sample of a 75-year-old woman. 16S rRNA gene sequence-based phylogenetic analysis showed that strain CCUG 53201T clustered with the type strains of species of the genus Ornithinibacillus. Strain CCUG 53201T was most closely related to Ornithinibacillus bavariensis WSBC 24001T and Ornithinibacillus californiensis DSM 16628T (97.9 and 98.7 % 16S rRNA gene sequence similarity, respectively). Strain CCUG 53201T contained a peptidoglycan of type A4β l-Orn–d-Asp. The quinone system was composed of the menaquinone MK-7 and small amounts of MK-6. The polar lipid profile of strain CCUG 53201T consisted of major amounts of diphosphatidylglycerol and an unidentified phospholipid, moderate amounts of phosphatidylglycerol and another two unidentified phospholipids and minor amounts of several other components. The fatty acid profile comprised mainly anteiso- and iso-branched fatty acids and was in accordance with those of members of the genus Ornithinibacillus. The polyamine pattern exhibited the major compounds spermidine and spermine. The results of physiological and biochemical tests and DNA–DNA hybridization allowed the phenotypic and genotypic differentiation of strain CCUG 53201T from its closest phylogenetic neighbours. We propose a novel species with the name Ornithinibacillus contaminans sp. nov., with type strain CCUG 53201T (=DSM 22953T).