Lysobacter tabacisoli sp. nov., isolated from rhizosphere soil of Nicotiana tabacum L.

Abstract

A Gram-stain-negative, aerobic, rod-shaped bacterium, designated strain C8-1T, was isolated from the rhizosphere soil of Nicotiana tabacum L. collected from Kunming, south-west China. The cells showed oxidase-positive and catalase-positive reactions. Growth was observed at 10-40 °C, at pH 6.0-8.0 and in the presence of up to 1% (w/v) NaCl, with optimal growth at 30 °C and pH 7.0. The predominant isoprenoid quinone was Q-8. The major fatty acids were identified as iso-C15: 0, iso- C17: 0 and iso-C17: 1ω9c. The cellular polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, five unidentified phospholipids and two unidentified aminophospholipids. The genomic DNA G+C content was 70.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain C8-1T should be assigned to the genus Lysobacter. 16S rRNA gene sequence similarity analysis showed that strain C8-1T was closely related to Lysobacter cavernae YIM C01544T (98.6%), Lysobacter soli DCY21T (97.6%), Lysobacter panacisoli CJ29T (97.3%), Lysobacter firmicutimachus PB-6250T (97.3%), Lysobacter niastensis GH41-7T (97.3%) and Lysobacter gummosus KCTC 12132T (97.1%). DNA-DNA hybridization data indicated that the isolate may represent a novel genomic species belonging to the genus Lysobacter. Polyphasic taxonomic characteristics indicated that strain C8-1T represents a novel species of the genus Lysobacter, for which the name Lysobacter tabacisoli sp. nov. is proposed. The type strain is C8-1T (=KCTC 62034T=CGMCC 1.16271T).