Hydrogenophaga intermedia sp. nov., a 4-aminobenzenesulfonate degrading organism

The taxonomic status of a gram-negative, oxidase positive rod (strain S1) able to degrade 4-aminobenzenesulfonate was studied using a polyphasic approach. Chemotaxonomic investigations of quinones and polar lipids established the allocation of this strain to the beta-subclass of the Proteobacteria and revealed similarities to Hydrogenophaga palleronii. 16S rRNA sequence comparisons demonstrated that this strain clusters phylogenetically with H. palleronii and H. taeniospiralis, but clearly represents a new species. The fatty acid patterns and substrate utilization profile displayed similarity to the characteristics of the four validly published species of Hydrogenophaga, although clear differentiating characters were also observed. No close similarities between the type strains of H. palleronii and H. taeniospiralis were detected in hybridization experiments with the genomic DNAs. On basis of these results, the new species Hydrogenophaga intermedia sp. nov. is proposed, with the type strain S1T (= DSM 5680).