Dyadobacter soli sp. nov., a starch-degrading bacterium isolated from farm soil

A Gram-negative, non-motile, aerobic bacterial strain, designated MJ20(T), was isolated from farm soil near Daejeon (South Korea) and was characterized taxonomically by using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain MJ20(T) belongs to the family Cytophagaceae, class Sphingobacteria, and was related most closely to Dyadobacter fermentans DSM 18053(T) (98.9 % sequence similarity), Dyadobacter beijingensis JCM 14200(T) (98.0 %) and Dyadobacter ginsengisoli KCTC 12589(T) (96.4 %). The G+C content of the genomic DNA of strain MJ20(T) was 48.5 mol%. The detection of MK-7 as the predominant menaquinone and a fatty acid profile with summed feature 4 (C(16 : 1)ω7c and/or iso-C(15 : 0) 2-OH), iso-C(15 : 0), C(16 : 0) and C(16 : 1)ω5c as major components supported the affiliation of strain MJ20(T) to the genus Dyadobacter. The new isolate exhibited relatively low levels of DNA-DNA relatedness with respect to D. fermentans DSM 18053(T) (mean±SD of three determinations, 47±7 %) and D. beijingensis JCM 14200(T) (38±8 %). On the basis of its phenotypic and genotypic properties together with phylogenetic distinctiveness, strain MJ20(T) (=KCTC 22481(T) =JCM 16232(T)) should be classified in the genus Dyadobacter as the type strain of a novel species, for which the name Dyadobacter soli sp. nov. is proposed.