Sphingobacterium hotanense sp. nov., isolated from soil of a Populus euphratica forest, and emended descriptions of Sphingobacterium daejeonense and Sphingobacterium shayense

Abstract

A novel Gram-staining-negative bacterial strain, designated XH4(T), was isolated from soil of a Populus euphratica forest in the Hotan River valley, Xinjiang Uyghur autonomous region, PR China. The cells were strictly aerobic, non-motile, short rods. The isolate grew optimally at 37 °C and at pH 7.0-8.0. Based on 16S rRNA gene sequence analysis, strain XH4(T) belonged to the genus Sphingobacterium and was closely related to Sphingobacterium mizutaii ATCC 33299(T) (96.1 % sequence similarity). The DNA G+C content was 41.2 mol%. The major polar lipid of strain XH4(T) was phosphatidylethanolamine, and several unidentified polar lipids were also present. Strain XH4(T) showed the typical chemotaxonomic features of the genus Sphingobacterium, with the presence of ceramide phosphorylethanolamine 2 (CerPE-2) as the major ceramide. The major cellular fatty acids of strain XH4(T) were iso-C15 : 0 (34.0 %), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 20.7 %) and iso-C17 : 0 3-OH (14.7 %). The predominant isoprenoid quinone was MK-7. On the basis of phenotypic data and phylogenetic inference, strain XH4(T) represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium hotanense sp. nov. is proposed. The type strain is XH4(T) ( = NRRL B-59204(T) = CCTCC AB 209007(T)). Emended descriptions of Sphingobacterium daejeonense and Sphingobacterium shayense are also given.