Lysinibacter cavernae gen. nov., sp. nov., a new member of the family Microbacteriaceae isolated from a karst cave

A Gram-stain-positive, aerobic, straight or slightly bent rod-shaped, non-motile, non-spore-forming bacterium, designated strain CC5-806T, was isolated from a soil sample collected from a wild karst cave in the Wulong region, Chongqing, PR China and examined using a polyphasic approach to clarify its taxonomic position. This bacterium did not produce substrate mycelium or aerial hyphae, and no diffusible pigments were observed on the media tested. Strain CC5-806T grew optimally without NaCl at 20 °C and at pH 7.0. Phylogenetic analysis, based on 16S rRNA gene sequences, indicated that strain CC5-806T belonged to the family Microbacteriaceae and showed the highest levels of 16S rRNA gene sequence similarities with Frigoribacterium endophyticum EGI 6500707T (97.56 %), Frigoribacterium faeni 801T (97.53 %) and Glaciihabitans tibetensis MP203T (97.42 %). Phylogenetic trees revealed that strain CC5-806T did not show a clear affiliation to any genus within the family Microbacteriaceae. The DNA G+C content of strain CC5-806T was 62.6 mol%. The cell-wall peptidoglycan contained l-lysine as a diagnostic diamino acid. The predominant menaquinones were MK-11, MK-10 and MK-9. Phosphatidylglycerol, diphosphatidylglycerol, an unidentified glycolipid, four unidentified phospholipids and other polar lipids were detected in the polar lipid extracts. The major fatty acids were anteiso-C15 : 0, iso-C16 : 0 and iso-C14 : 0. On the basis of the phylogenetic analysis, and phenotypic and chemotaxonomic characteristics, strain CC5-806T was distinguishable from phylogenetically related genera in the family Microbacteriaceae. It represents a novel species of a novel genus, for which the name Lysinibacter cavernae gen. nov., sp. nov. is proposed. The type strain is CC5-806T ( = DSM 27960T = CGMCC 1.14983T).