Sphingobacterium nematocida sp. nov., a nematicidal endophytic bacterium isolated from tobacco.

A novel Gram-negative strain, designated M-SX103(T), was isolated from a fresh leaf of Nicotiana tabacum Linn. collected at Yuxi City, Yunnan province, China, and subjected to a polyphasic taxonomic study. Growth occurred at 10-40 °C, at pH 6.0-9.0 and with 0-3% (w/v) NaCl. The predominant isoprenoid quinone was MK-7. The major cellular fatty acids of strain M-SX103(T) were iso-C(15:0), iso-C(17:0) 3-OH and summed feature 3 (C(16:1)ω7c and/or C(16:1)ω6c). The G+C content of the genomic DNA was 40.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belongs to the genus Sphingobacterium, sharing 95.4-89.7% sequence similarity with type strains of members of the genus Sphingobacterium; it was most closely related to Sphingobacterium composti T5-12(T). On the basis of the taxonomic evidence, a novel species, Sphingobacterium nematocida sp. nov., is proposed. The type strain is M-SX103(T) ( = JCM 17339(T) = CCTCC AB 2010390(T)).