Sphingomonas psychrolutea sp. nov., a psychrotolerant bacterium isolated from glacier ice

A Gram-stain-negative, rod-shaped, orange bacterium (strain MDB1-A^T) was isolated from ice samples collected from Midui glacier in Tibet, south-west China. Cells were aerobic and psychrotolerant (growth occurred at 0–25°C). Phylogenetic analysis based on 16S rRNA gene sequences showed that it was a member of the genus Sphingomonas, with its closest relative being Sphingomonas glacialis C16y^T (98.9% similarity). Q-10 was the predominant ubiquinone. C_17:1ω6c and summed feature 8 (C_18:1ω6c and/or C_18:1ω7c) were the major cellular fatty acids. The predominant polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and sphingoglycolipid. The polyamines detected were sym-homospermidine, spermidine and spermine. The G+C content of the genomic DNA was 63.6%. Based on data from this polyphasic analysis, strain MDB1-A^Trepresents a novel species of the genus Sphingomonas, for which the name Sphingomonas psychrolutea sp. nov. is proposed. The type strain is MDB1-A^T (=CGMCC 1.10106^T=NBRC 109639^T).