Three strains of a Gram-stain negative bacterium were isolated from Lake Michigan water. 16S rRNA gene sequence analysis revealed that strain 1131 had sequence similarities to Bosea vaviloviae LMG 28367T, Bosea lathyri LMG 26379T, Bosea lupini LMG 26383T, Bosea eneae CCUG 43111T, Bosea vestrisii CCUG 43114T and Boseamassiliensis CCUG 43117T of 99.8, 99.1, 98.4, 98.4, 98.4 and 98.2 %, respectively. The average nucleotide identity value between strain 1131T and Bosea vaviloviae Vaf-18T was 93.4 % and the DNA relatedness was 38 %. The primary cellular fatty acids of strain 1131T were C16 : 1ω7c and C18 : 1ω7c. The primary polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine. The major compound in the quinone system was ubiquinone Q-10 and in the polyamine pattern sym-homospermidine was predominant. Additional phenotypic characteristics included growth at 5-35 °C, pH values of pH 5.5-8.0, a salt tolerance range of 0.0-1.2 % (w/v), and production of an unknown water soluble brown pigment. After phenotypic, chemotaxonomic and genomic analyses, this isolate was identified as a novel species for which the name Bosea psychrotolerans is proposed. The type strain is 1131T (NRRL B-65405=LMG 30034).
Keywords: Bosea; psychrotolerans; psychrotroph.