Genes of NAD + -Dependent Formate Dehydrogenases in Taxonomy of Aerobic Methylotrophic Bacteria of the Genus Ancylobacter

— Comparative phylogenetic analysis of NAD + -dependent formate dehydrogenases (NAD + -FDH) genes, which have been detected in all available genomes of methylotrophs of the genera Ancylobacter , Starkeya , and Angulomicrobium , as well as in other members of the family Xanthobacteraceae ( Xanthobacter , Aquabacter , Azorhizobium ), was carried out. The position of Xanthobacteraceae on the tree constructed based on comparison of NAD + −FDH amino acid sequences was found to correlate with the 16S rRNA gene-based phylogeny. The sequences of the NAD + −FDH proteins of the genera Ancylobacter , Starkeya , and Angulomi-crobium exhibited 87.8–98.3% identity, indicating that this protein is very conservative within this group of methylotrophs. For the first time, analysis of the NAD + −FDH functional genes is recommended as a supplementary criterion for interspecies differentiation between methylotrophic bacteria of the genus Ancylobacter .