Ornithinimicrobium humiphilum gen. nov., sp nov., a novel soil actinomycete with L-ornithine in the peptidoglycan

A Cram-positive bacterium originating from garden soil was taxonomically st udied. Cells are non-motile, non-sporulating, irregular rods and cocci. The cell wall peptidoglycan contains L-ornithine as diagnostic diamino acid an d an interpeptide bridge consisting of L-Orn <--L-Ala <-- Gly <--D-Asp. The major menaquinone is MK-8(H-4). 13-Methyl tetradecanoic acid and 14-methyl pentadecanoic acid are the predominant fatty acids. The polar lipids are p hosphatidylinositol, phosphatidylglycerol, diphosphatidylglycerol, three un known glycolipids and three unknown phospholipids. Mycolic acids are absent , The DNA G+C composition is 70 mol%. The acyl type of the glycan chain of peptidoglycan is acetyl. Glucose is the dominating whole cell sugar; arabin ose, rhamnose and xylose are present in traces. Results of 16S rDNA sequenc e comparisons revealed that strain HKI 0124(T) represents a novel lineage w ithin the suborder Micrococcineae of the order Actinomycetales adjacent to the recently described genus Ornithinicoccus. On the basis of the clearly p ronounced morphological physiological, chemotaxonomic and phylogenetic diff erences between strain HKI 0124(T) and all members of the suborder Micrococ cineae, if is proposed to assign strain HKI 0124(T) to a new genus and spec ies, Ornithinimicrobium humiphilum gen. nov., sp. nov. The type and only st rain is HKI 0124(T)(= DSM 12362(T) = CIP 106634(T)).