Characterization of Sinomonas gamaensis sp. nov., a Novel Soil Bacterium with Antifungal Activity against Exserohilum turcicum.

ABSTRACT

A novel Gram staining positive, aerobic bacterium NEAU-HV1T that exhibits antifungal activity against Exserohilum turcicum was isolated from a soil collected from Gama, Hadjer lamis, Chad. It was grown at 10-45 °C (optimum 30 °C), pH 5-10 (optimum pH 8), and 0-4% (w/v) NaCl (optimum 1%). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain NEAU-HV1T was closely related to Sinomonas susongensis A31T (99.24% sequence similarity), Sinomonas humi MUSC 117T (98.76%), and Sinomonas albida LC13T (98.68%). The average nucleotide identity values between NEAU-HV1T and its most closely related species were 79.34-85.49%. The digital DNA-DNA hybridization values between NEAU-HV1T and S. susongensis A31T, S. albida LC13T, and S. humi MUSC 117T were 23.20, 23.50, and 22.80%, respectively, again indicating that they belonged to different taxa. The genomic DNA G+C content was 67.64 mol%. The whole cell sugars contained galactose, mannose, and rhamnose. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, and four glycolipids. The respiratory quinone system comprised MK-9(H2), MK-10(H2), and MK-8(H2). The major cellular fatty acids (>5%) were anteiso-C150, anteiso-C170, C160, and iso-C150. Based on the polyphasic analysis, it is suggested that the strain NEAU-HV1T represents a novel species of the genus Sinomonas, for which the name Sinomonas gamaensis sp. nov. is proposed. The type strain is NEAU-HV1T (= DSM 104514T = CCTCC M 2017246T).