Pseudomonas campi sp. nov., a nitrate-reducing bacterium isolated from grassland soil

A novel strain was isolated from grassland soil that has the potential to assimilate ammonium by the reduction of nitrate in the presence of oxygen. Whole genome sequence analysis revealed the presence of an assimilatory cytoplasmic nitrate reductase gene and the assimilatory nitrite reductase genes which are involved in the sequential reduction of nitrate to nitrite and further to ammonium, respectively. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate represents a member of the genus . The closest phylogenetic neighbours based on 16S rRNA gene sequence analysis are the type strains of (98.17%) and (98.03%). In contrast, phylogenomic analysis revealed a close relationship to . Computation of the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) with the closest phylogenetic neighbours of S1-A32-2 revealed genetic differences at the species level, which were further substantiated by differences in several physiological characteristics. On the basis of these results, it was concluded that the soil isolate represents a novel species of the genus for which the name sp. nov. (type strain S1-A32-2 =LMG 31521 =DSM 110222 ) is proposed.