Microbacterium petrolearium sp. nov., isolated from an oil-contaminated water sample.

A Gram-staining-positive, rod-shaped, aerobic bacterium, designated strain LAM0410(T), was isolated from an oil-contaminated water sample from the Dagang Oilfield, PR China. The temperature and pH ranges for growth were 4 °C to 50 °C and pH 4.4 to pH 12.0, respectively. The strain did not need NaCl for growth, but could tolerate a concentration of up to 12 % (w/v). Cell wall hydrolysates from the isolate showed that the diamino acid was ornithine. The cell wall sugars contained ribose and galactose. The glycan moiety of the cell wall contained N-glycolyl residues. The major respiratory quinones were MK-10, MK-11 and MK-12. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and nine unknown glycolipids. The major fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. 16S rRNA gene sequence analysis indicated that the isolate belonged to the genus Microbacterium and was closely related to Microbacterium sediminis MCCC 1A06153(T) and Microbacterium murale DSM 22178(T) with 97.5 % and 97.4 % sequence similarities, respectively; while the DNA-DNA hybridization values were 33.1±3.4 % and 21.8±1.6 %, respectively. The DNA G+C content was 67.4 mol%, as determined by the Tm method. Based on its phenotypic and genotypic properties, strain LAM0410(T) represents a novel species of the genus Microbacterium, for which the name Microbacterium petrolearium sp. nov. is proposed; the type strain is LAM0410(T) ( = ACCC 00719(T) = JCM 19612(T)).