Sphingosinicella cucumeris sp. nov., isolated from soil of a cucumber garden

A novel bacterial strain, THG-sc1(T), was isolated from a soil sample of a cucumber garden and was characterised by using a polyphasic approach. Cells were observed to be Gram-stain negative, non-motile and rod-shaped. The strain was found to be aerobic, catalase and oxidase positive, esculin and starch negative, and to have an optimum growth temperature and pH of 28 °C and 7.5, respectively. On the basis of 16S rRNA gene sequence analysis, strain THG-sc1(T) was found to belong to the genus Sphingosinicella and to be closely related to Sphingosinicella vermicomposti KCTC 22446(T), followed by Sphingosinicella xenopeptidilytica DSM 17130(T) and Sphingosinicella microcystinivorans KCTC 12019(T). The DNA G+C content was determined to be 60.8 mol% and the predominant respiratory quinone was identified as ubiquinone-10. The major polyamine was found to be sym-homospermidine. The major polar lipids were identified as sphingoglycolipid, phosphatidylethanolamine, phosphatidylglycerol and an unidentified phospholipid. The major fatty acids were identified as C(18:1)ω7c, C(16:0) and summed feature 3 (C(16:1)ω7c and/or iso-C(15:0) 2-OH, as defined by MIDI). The results of the genotypic analysis, in combination with chemotaxonomic and physiological data, demonstrated that strain THG-sc1(T) represents a novel species within the genus Sphingosinicella, for which the name Sphingosinicella cucumeris is proposed. The type strain is THG-sc1(T) (=KACC 18279(T) = CCTCC AB 2015120(T)).