Winogradskyella exilis sp. nov., isolated from the starfish Stellaster equestris, and emended description of the genus Winogradskyella

Abstract

A pale-yellowish-pigmented strain, 022-2-26T, was isolated from a starfish, Stellaster equestris. Cells of strain 022-2-26T were Gram-negative short rods that were chemo-organotrophic, alkalitolerant and mesophilic. The predominant menaquinone was MK-6. The major cellular fatty acids were iso-C15 : 0, iso-C15 : 1, C15 : 0, iso-C15 : 0 2-OH and iso-C17 : 0 3-OH (together representing 87 % of the total fatty acids). The DNA G+C content was 30.1 mol%. A 16S rRNA gene sequence of the isolate was determined and phylogenetic analyses revealed that strain 022-2-26T formed a robust clade (neighbour-joining algorithm with a bootstrap value of 95 % and parsimony and maximum-likelihood algorithms) with type strains of species in the genus Winogradskyella. The closest phylogenetic neighbour of strain 022-2-26T was Winogradskyella poriferorum UST030701-295T (96 % 16S rRNA gene sequence similarity; 59 differences between sequences). On the basis of the phenotypic and chemotaxonomic characteristics and the phylogenetic evidence, it is proposed that strain 022-2-26T represents a novel species, Winogradskyella exilis sp. nov. The type strain is 022-2-26T (=KMM 6013T =CIP 109976T).