Description of Pelomonas aquatica sp. nov. and Pelomonas puraquae sp. nov., isolated from industrial and haemodialysis water

<jats:p>Three Gram-negative, rod-shaped, non-spore-forming bacteria (strains CCUG 52769<jats:sup>T</jats:sup>, CCUG 52770 and CCUG 52771) isolated from haemodialysis water were characterized taxonomically, together with five strains isolated from industrial waters (CCUG 52428, CCUG 52507, CCUG 52575<jats:sup>T</jats:sup>, CCUG 52590 and CCUG 52631). Phylogenetic analysis based on 16S rRNA gene sequences indicated that these isolates belonged to the class<jats:italic>Betaproteobacteria</jats:italic>and were related to the genus<jats:italic>Pelomonas</jats:italic>, with 16S rRNA gene sequence similarities higher than 99 % with the only species of the genus,<jats:italic>Pelomonas saccharophila</jats:italic>and to<jats:italic>Pseudomonas</jats:italic>sp. DSM 2583. The type strains of<jats:italic>Mitsuaria chitosanitabida</jats:italic>and<jats:italic>Roseateles depolymerans</jats:italic>were their closest neighbours (97.9 and 97.3 % 16S rRNA gene sequence similarity, respectively). Phylogenetic analysis was also performed for the internally transcribed spacer region and for three genes [<jats:italic>hoxG</jats:italic>(hydrogenase),<jats:italic>cbbL</jats:italic>/<jats:italic>cbbM</jats:italic>(Rubisco) and<jats:italic>nifH</jats:italic>(nitrogenase)] relevant for the metabolism of the genus<jats:italic>Pelomonas</jats:italic>. DNA–DNA hybridization, major fatty acid composition and phenotypical analyses were carried out, which included the type strain of<jats:italic>Pelomonas saccharophila</jats:italic>obtained from different culture collections (ATCC 15946<jats:sup>T</jats:sup>, CCUG 32988<jats:sup>T</jats:sup>, DSM 654<jats:sup>T</jats:sup>, IAM 14368<jats:sup>T</jats:sup>and LMG 2256<jats:sup>T</jats:sup>), as well as<jats:italic>M. chitosanitabida</jats:italic>IAM 14711<jats:sup>T</jats:sup>and<jats:italic>R. depolymerans</jats:italic>CCUG 52219<jats:sup>T</jats:sup>. Results of DNA–DNA hybridization, physiological and biochemical tests supported the conclusion that strains CCUG 52769, CCUG 52770 and CCUG 52771 represent a homogeneous phylogenetic and genomic group, including strain DSM 2583, clearly differentiated from the industrial water isolates and from the<jats:italic>Pelomonas saccharophila</jats:italic>type strain. On the basis of phenotypic and genotypic characteristics, these strains belong to two novel species within the genus<jats:italic>Pelomonas</jats:italic>, for which the names<jats:italic>Pelomonas puraquae</jats:italic>sp. nov. and<jats:italic>Pelomonas aquatica</jats:italic>sp. nov. are proposed. The type strains of<jats:italic>Pelomonas puraquae</jats:italic>sp. nov. and<jats:italic>Pelomonas aquatica</jats:italic>sp. nov. are CCUG 52769<jats:sup>T</jats:sup>(=CECT 7234<jats:sup>T</jats:sup>) and CCUG 52575<jats:sup>T</jats:sup>(=CECT 7233<jats:sup>T</jats:sup>), respectively.</jats:p>