Lysobacter humi sp. nov., a bacterium isolated from rice field

A novel bacterial strain THG-PC4^T was isolated from soil sample of rice field and was characterized by using a polyphasic approach. Cells were Gram-negative, bright yellow colored, nonmotile and rod shaped. The strain was aerobic and catalase positive, optimum growth temperature, and pH were 28 °C and 7, respectively. On the basis of 16S rRNA gene sequence analysis, strain THG-PC4^T belongs to the genus Lysobacter and is most closely related to Lysobacter fragariae KCTC 42236^T, followed by Lysobacter oryzae KCTC 22249^T, Lysobacter tyrosinelyticus KCTC 42235^T, Lysobacter terrae KACC 17646^T, Lysobacter yangpyeongensis KACC 11407^T, Lysobacter rhizosphaerae KCTC 42237^T and Lysobacter niabensis KACC 11587^T. In DNA-DNA hybridization tests, the DNA relatedness between strain THG-PC4^T and its closest phylogenetic neighbors was below 45 %. The DNA G + C content was 66.6 mol %, and the predominant respiratory quinone was ubiquinone-8. Flexirubin-type pigments were found to be present. The major cellular fatty acids were iso-C_16:0, iso-C_17:1 ω9c, iso-C_17:0 and iso-C_11:0 3OH. The predominant polar lipids were phosphatidylethanolamine and phosphatidylglycerol. The DNA-DNA hybridization, genotypic, chemotaxonomic and physiological data demonstrated that strain THG-PC4^T represented a novel species within the genus Lysobacter, for which the name Lysobcater humi is proposed. The type strain is THG-PC4^T (=KACC 18284^T = CCTCC AB 2015292^T).