Sphingobium baderi sp nov., isolated from a hexachlorocyclohexane dump site

A Gram-stain-negative, rod-shaped and white-coloured bacterial strain, designated LL03(T), was isolated from hexachlorocyclohexane-contaminated soil at Spolana Neratovice, Czech Republic, where lindane was formerly produced. Strain LL03(T) was found to be a degrader of alpha-, gamma- and delta-isomers of hexachlorocyclohexane, although no significant degradation activity was observed for the beta-isomer. A neighbour-joining tree based on 16S rRNA gene sequences showed that strain LL03(T) occupied a distinct phylogenetic position in the Sphingobium cluster, showing the highest similarity with Sphingobium wenxiniae JZ-1(T) (99.2 %). The DNA G+C content of strain LL03(T) was 67.0 mol%. DNA DNA relatedness values of strain LL03(T) with its close phylogenetic neighbours were below the threshold level of 70%, supporting its identification as a representative of a novel species of the genus Sphingobium. The predominant respiratory quinone was ubiquinone Q-10. The polar lipid profile of strain LL03(T) also corresponded to those reported for other Sphingobium species (phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, phosphatidylmonomethylethanolamine and sphingoglycolipid), supporting its identification as a member of the genus Sphingobium. Spermidine was identified as the major polyamine. The predominant fatty acids were 16:0, summed feature 3 (16:1 omega 7c and/or 16:1 omega 6c), summed feature 8 (18:1 omega 7c and/or 18:1 omega 6c) and 14:0 2-OH. The polar lipid pattern, the presence of spermidine and ubiquinone Q-10, the predominance of the cellular fatty acids C-18:1 omega 7c, C-16:0 and C-14:0 2-OH and the G+C content of the genomic DNA supported the affiliation of the strain to the genus Sphingobium. The results obtained after DNA DNA hybridization, biochemical and physiological tests clearly distinguished it from closely related species of the genus Sphingobium. Therefore, strain LL03(T) represents a novel species of the genus Sphingobium for which the name Sphingobium baderi LL03(T) sp. nov. is proposed; the type strain is LL03(T) (=CCM 7981(T)=DSM 25433(T)).