Hymenobacter psychrophilus sp. nov., a psychrophilic bacterium isolated from soil

A non-motile, rod-shaped, red-pigmented bacterium, designated strain BZ33rT, was isolated from soil of an industrial site. The organism exhibited Gram-negative staining, was aerobic and psychrophilic, and demonstrated good growth at 1–20°C. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain BZ33rT is closely related to members of the genus Hymenobacter, particularly Hymenobacter aerophilus DSM 13606T, with a sequence similarity of 97.5%. The predominant cellular fatty acids identified were anteiso-C15:0, summed feature 3, iso-C15:0, summed feature 4, and C16:1v5c. The major menaquinone was MK-7, and the polyamine pattern was characterized by sym-homospermidine as the major compound, alongside moderate amounts of spermidine. Additionally, a diverse polar lipid profile was documented, including phosphatidylethanolamine and several unidentified lipids. The G+C content of the DNA was determined to be 61.6 mol%. Based on phenotypic characteristics, phylogenetic implications, and DNA–DNA relatedness data, strain BZ33rT is proposed as a novel species of the genus Hymenobacter, named Hymenobacter psychrophilus sp. nov., with the type strain BZ33rT (DSM 22290T, CGMCC 1.8975T, LMG 25548T).