Abstract

The bacterial strain M1T8B10T was isolated from cow dung in Suwon, Republic of Korea. The strain was a Gram stainpositive rod, nonmotile, and non-spore-forming. According to 16S rRNA gene sequence analysis, the strain fell within the clade of the genus Leucobacter, showing the highest sequence similarities with Leucobacter aridicollis L-9T (98.7%), Leucobacter iarius 40T (98.4%), and Leucobacter komagatae JCM 9414T (98.2%). Cell-wall peptidoglycan contained the diagnostic diamino acid 2,4-diaminobutyric acid of the genus Leucobacter, showing B-type cross-linked peptidoglycans. The major fatty acids were anteiso-C15:0, iso-C16:0, and anteiso- C17:0. The quinone system consisted of the menaquinones MK-11 (78%) and MK-10 (22%). The polar lipid profiles contained diphosphatidylglycerol, phosphatidylglycerol, and an unidentified glycolipid. Differences in several physiological features including nitrate reduction enabled the isolate to be differentiated from all recognized Leucobacter species. Based on these phylogenetic, chemotaxonomic, and phenotypic results, the isolate represents a novel species, for which the name Leucobacter denitrificans sp. nov. is proposed. The type strain is M1T8B10T (=KACC 14055T =NBRC 106309T).

• Keywords: Leucobacter denitrificans sp. nov.; taxonomy; 16S rRNA gene; phylogeny; new species