Spirosoma endbachense sp. nov., isolated from a natural salt meadow

Abstract

A Gram-stain-negative bacterium, designated I-24T, was isolated from soil of a natural salt meadow. Strain I-24T was aerobic, non-motile, rod-shaped, catalase-positive, oxidase-positive and grew optimally at pH 7 and 25 °C. Comparative 16S rRNA gene analysis indicated that strain I-24T has closest similarities to Spirosoma agri KCTC 52727T (95.9 %) and Spirosoma terrae KCTC 52035T (95.5 %). Strain I-24T contained summed feature 3 (C16 : 1  ω7c/C16 : 1  ω6c) and C16 : 1  ω5c as the major fatty acids, the predominant respiratory quinone was menaquinone MK-7, and the major polar lipids were phosphatidylethanolamine as well as an unidentified phosphoaminolipid. The draft genome of strain I-24T consists of 10 326 072 base pairs with 9153 predicted coding sequences and a G+C content of 47.7 mol%. Clear distinctions between strain I-24T and S. agri KCTC 52727T or S. terrae KCTC 52035T were shown in the pairwise average nucleotide identity results with values of 76.71 and 74.01 %, respectively. Moreover, the digital DNA–DNA relatedness values to these strains were 20.8 and 19.0 %. Based on its phenotypic, genotypic and chemotaxonomic characteristics, strain I-24T represents a novel species of the genus Spirosoma , for which the name Spirosoma endbachense sp. nov. is proposed. The type strain is I-24T (DSM 111055T=KCTC 72613T).