6dehydrogenase

6-dehydrogenase, sometimes written 6dehydrogenase, is not a single officially recognized enzyme entry in standard biochemical nomenclature. Rather, it is an informal label that can refer to any oxidoreductase that removes hydrogen from a substrate at or related to a sixth carbon, or from a six-carbon substrate. In general, dehydrogenases catalyze oxidation reactions in which a substrate is converted to a more oxidized form while a cofactor such as NAD+ or NADP+ is reduced to NADH or NADPH.

Because dehydrogenases typically use NAD+ or NADP+ as electron acceptors, a hypothetical 6-dehydrogenase would be expected to transfer hydrogens to these cofactors and often to participate in metabolic pathways that balance carbon metabolism with cellular redox state. The exact chemistry, substrate specificity, and cellular role depend on the individual enzyme.

A representative example that illustrates the spirit of the name is 6-phosphogluconate dehydrogenase (EC 1.1.1.44). This enzyme acts on the six-carbon sugar derivative 6-phosphogluconate in the pentose phosphate pathway, catalyzing its oxidation to ribulose-5-phosphate with NADP+ as cofactor and release of CO2, contributing to NADPH production and ribose-5-phosphate synthesis. That enzyme is widely studied and serves as a concrete instance of a six-carbon substrate dehydrogenase-like activity.

In summary, 6-dehydrogenase is not a distinct, universally defined enzyme class; rather, it may refer to dehydrogenases with connections to six-carbon substrates or position-specific oxidation, and its precise identity is determined by substrate, pathway context, and naming conventions.