Nitratireductor lucknowense sp. nov., a novel bacterium isolated from a pesticide contaminated soil.

A straw-yellow pigmented bacterium, strain IITR-21(T) was isolated from a pesticide contaminated site and characterized by using a polyphasic taxonomic approach. The organism had morphological and chemotaxonomic properties consistent with its classification in the genus Nitratireductor. Phylogenetic analysis of the 16S rRNA gene sequence showed that the strain IITR-21(T) belongs to the genus Nitratireductor and was moderately related to Nitratireductor indicus C115(T) (97.7%) and Nitratireductor pacificus pht-3B(T) (97.4%), whereas sequence similarity value with the other species including the type species of the genus Nitratireductor, Nitratireductor aquibiodomus showed less than 97.0% similarity. However, the DNA-DNA relatedness values between strain IITR-21(T) and the moderately related taxa N. indicus (59.1%) and N. pacificus (40.4%) were well below the 70% threshold value recommended for the delineation of bacterial species. The G+C content of the DNA was 62.4 mol%. Based on physiological, biochemical tests and genotypic differences between the strain IITR-21(T) and the other two validly published species of the genus Nitratireductor, it is proposed that the strain be classified as a new species of Nitratireductor as Nitratireductor lucknowense sp. nov. The type strain is IITR-21(T) (=MTCC 8354(T )= DSM 24322(T)).