The Auxiliary NADH Dehydrogenase Plays a Crucial Role in Redox Homeostasis of Nicotinamide Cofactors in the Absence of the Periplasmic Oxidation System in Gluconobacter oxydans NBRC3293.

has the unique property of a glucose oxidation system in the periplasmic space, where glucose is oxidized incompletely to ketogluconic acids in a nicotinamide cofactor-independent manner. Elimination of the gene for membrane-bound glucose dehydrogenase, the first enzyme for the periplasmic glucose oxidation system, induces a metabolic change whereby glucose is oxidized in the cytoplasm to acetic acid. strain NBRC3293 possesses two molecular species of type II NADH dehydrogenase (NDH), the primary and auxiliary NDHs that oxidize NAD(P)H by reducing ubiquinone in the cell membrane.

Diversity of NADH dehydrogenases in acetic acid bacteria: adaptation to modify their phenotype through gene expansions and losses and neo-functionalization.

NADH dehydrogenase plays an important role in the central metabolism of almost all organisms, including acetic acid bacteria (AAB). In this study, the gene diversity of the NADH dehydrogenases in AAB was investigated. The distribution of the genes of the type I and type II NADH dehydrogenases in AAB was mostly congruent with their phylogenetic relationships.