Abstract
A gram-positive bacterium, strain K-540BT, which was separated from a mixed culture isolated from compost, was subjected to a polyphasic taxonomic study. Strain K-540BT was found to have 95.5%-98.7% sequence similarity with the genus Leucobacter based on 16S rRNA gene sequence analyis. Phenotypic and chemical properties of strain K-540BT were consistent with its classification in the genus Leucobacter. The major quinone system compound was MK-11 and major fatty acids were anteiso-C15:0 and iso-C16:0. Polar lipids included phosphatidylglycerol and diphosphatidylglycerol. The G+C content of the genomic DNA was 64.9 mol%. The cell wall peptidoglycan contained diaminobutyric acid and γ-aminobutyric acid. DNA-DNA hybridization results and physiological tests genotypically and phenotypically differentiated strain K-540BT from other Leucobacter species. Based on these results, strain K-540BT (=NBRC 106062T=DSM 22850T), for which the name Leucobacter exalbidus sp. nov. is proposed, represents a novel species of the genus Leucobacter.