Defluvibacter lusatiae gen. nov., sp nov., a new chlorophenol-degrading member of the alpha-2 subgroup of proteobacteria

The two Gram-negative bacterial strains S1 and S4 were isolated from activa ted sludge of an industrial waste water treatment plant and exhibited a sta ble capability to degrade 2,4-dichlorophenol, 4-chloro-2-methylphenol, 4-ch lorophenol and phenol. The cells were short rods with a polar flagellum, be ing mesophilic, strictly aerobic, oxidase-positive, and chemoorganotrophic. They utilized a range of amino acids, but only a restricted number of carb ohydrates. Reassociation experiments with DNA from strains S1 and S4 reveal ed high interstrain similarity, indicating, that both strains belong to the same species. The phylogenetic position was determined by comparison of th e almost complete 16S rDNA sequence of strain S1 with sequences of related bacteria. Strain S1 clustered with members of the alpha-2 subgroup of the P roteobacteria by forming a separate lineage within the radiation of Mesorhi zobium, Phyllobacterium and Sinorhizobium. Both strains can be differentiat ed from members of related taxa by a set of physiological and chemotaxonomi c properties including the ability to grow with norvaline, L-tryptophan, pu trescine, glutarate and malonate, and by the presence of spermidine as majo r polyamine and of 12:0 30H as fatty acid. Strain S1 is described as type s train of a new species and assigned to a new genus with the proposed name D efluvibacter lusatiae.