Sphingomonas metalli sp. nov., isolated from an abandoned lead-zinc mine.

A Gram-stain-negative and non-motile bacterial strain designated 9O-5T was isolated from an abandoned lead-zinc mine in Meizhou, Guangdong Province, southern China. The isolate was orange-pigmented, aerobic, and oxidase- and catalase-positive. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain 9O-5T belongs to the genus Sphingomonas and was closely related to Sphingomonas abaci DSM 15867T (97.6 % similarity), Sphingomonas phyllosphaerae FA2T (96.9 %) and Shingomonas guangdongensis 9NM-8T (96.8 %). Mean DNA-DNA relatedness between strain 9O-5T and S. abaci DSM 15867T was only 47.1 ± 4.9 %. The major fatty acids were C18 : 1ω7c, C14 : 0 2-OH and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). It contained Q-10 as the predominant respiratory quinone and sym-homospermidine as the major polyamine. The polar lipids were sphingoglycolipid, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, five unidentified phospholipids and six unidentified lipids. The genomic DNA G+C content of strain 9O-5T was 69.1 ± 0.1 mol%. Based on the data from this polyphasic taxonomic study, strain 9O-5T should be considered as representing a novel species of the genus Sphingomonas, for which the name Sphingomonas metalli sp. nov. is proposed. The type strain is 9O-5T ( = CGMCC 1.15330T = KCTC 42759T).