Leifsonia stereocauli sp. nov., Isolated from Stereocaulon tomentosum Fr. Lichen

A Gram-stain-positive, aerobic, yellow-pigmented, catalase-positive, oxidase-positive, non-motile with no flagella and irregularly rod-shaped, denominated strain YIM 134122(T), was isolated from a Stereocaulon tomentosum Fr. lichen gathered on Baima Snow Mountain in Diqing Tibetan Autonomous Prefecture, Yunnan Province, China. The novel strain grew at pH 6.0-8.0 (optimum, pH 7.0-7.2), 4-35 degrees C (optimum,25-35 degrees C), and with the existence of 0-10% (w/v) NaCl (optimum, 0-2%). Phylogenetic analysis on the basis of 16S rRNA gene sequences indicated that strain YIM 134122(T) belonged to the genus Leifsonia and presented high levels of 16S rRNA gene sequence similarity with Leifsonia kafniensis JCM 17021(T) (97.92%) and Leifsonia psychrotolerans CGMCC 1.12166(T) (97.79%). Based on the draft genome sequence, the G + C content of strain YIM 134122(T) was found to be 68.41%, and the average nucleotide identity and digital DNA-DNA hybridizations values between strain YIM 134122(T) and Leifsonia kafniensis JCM 17021(T) and Leifsonia psychrotolerans CGMCC 1.12166(T) were 73.78% and 73.75%, and 19.6% and 19.9%, respectively, which were extremely lower than the generally proposed threshold value for species delineation. The predominant polar lipids in strain YIM 134122(T) consisted of phosphatidylglycerol, diphosphatidylglycerol, three unknown glycolipids, two unknown phospholipids, and one unknown lipid, whereas MK-10, MK-11 and MK-12 were the main menaquinones. The major fatty acids (> 4%) of the strain contained iso-C-15:0, anteiso-C-15:0, iso-C-16:0 and anteiso-C-17:0. On the basis of phylogenetic, chemotaxonomic, phenotypic and genotypic evidences, it is concluded that strain YIM 134122(T) represents a novel species of the genus Leifsonia, for with the name Leifsonia stereocauli sp. nov. is proposed. The type strain is YIM 134122(T) (= CGMCC 1.62033(T) = MCCC 1K08590(T) = KCTC 59219(T)).