Devosia psychrophila sp. nov. and Devosia glacialis sp. nov., from alpine glacier cryoconite, and an emended description of the genus Devosia

Abstract

Two psychrophilic strains, Cr7-05(T) and Cr4-44(T), isolated from alpine glacier cryoconite, were characterized by using a polyphasic approach. Both strains were psychrophilic, showing good growth over a temperature range of 1-20 °C. The chemotaxonomic characteristics of these isolates included the presence of C(18:1)ω7c and summed feature 3 (C(16:1)ω7c and/or C(16:1)ω6c) as the major cellular fatty acids, Q-10 as the predominant ubiquinone and diphosphatidylglycerol, phosphatidylglycerol and unknown glycolipids as major polar lipids. The DNA G+C contents of strains Cr7-05(T) and Cr4-44(T) were 61.4 and 63.6 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the two isolates belong to the genus Devosia. The 16S rRNA gene sequence similarity between the two strains was 98.6%, but DNA-DNA hybridization indicated 54% relatedness. Strains Cr7-05(T) and Cr4-44(T) exhibited 16S rRNA gene sequence similarity of 94.7-97.2 and 94.9-96.9%, respectively, to the type strains of recognized Devosia species. On the basis of phenotypic characteristics, phylogenetic analysis and DNA-DNA relatedness data, strains Cr7-05(T) and Cr4-44(T) represent two novel species within the genus Devosia, for which the names Devosia psychrophila sp. nov. (type strain Cr7-05(T) =DSM 22950(T) =CGMCC 1.10210(T) =CIP 110130(T)) and Devosia glacialis sp. nov. (type strain Cr4-44(T) =CGMCC 1.10691(T) =LMG 26051(T)) are proposed. An emended description of the genus Devosia is also provided.