Abstract
In this study, we report a Gram-stain-negative, rod-shaped, non-pigmented, motile and aerobic bacterium named strain MTZ26T, which was isolated from deep-sea sediment sampled at a cold seep in the South China Sea. Growth of strain MTZ26T occurred at 4-40 °C (optimum, 25-30 °C), pH 6.0-10.0 (optimum, 7.0-8.0) and with 1.0-11.0 % (w/v) NaCl (optimum, 6.0-8.0 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain MTZ26T belonged to the genus Psychrosphaera and was closely related to Psychrosphaera aestuarii PSC101T (97.5 % sequence similarity) and Psychrosphaera haliotis KDW4T (97.5 %). Genomic analysis indicated that strain MTZ26T contains a circular chromosome of 3 331 814 bp with G+C content of 42.2 mol%. The predominant respiratory quinone of MTZ26T was ubiquinone-8. The polar lipids of MTZ26T contained phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminophospholipid and one unidentified phospholipid. The major fatty acids of strain MTZ26T contained C15:0, C16:0, C17:0, C17 : 1 ω8c, C10 : 0 3-OH, C11 : 0 3-OH, C15 : 1 ω8c and summed feature 8 (C18 : 1 ω7c or/and C18 : 1 ω6c). Results of phylogenetic, physiological, biochemical and morphological analyses suggested that strain MTZ26T represents a novel species of the genus Psychrosphaera, and the name Psychrosphaera ytuae sp. nov. is proposed with the type strain MTZ26T (=MCCC 1K05568T=JCM 34321T).
