Regeneration of NAD⁺ cofactor by photosensitized electron transfer in an immobilized alcohol dehydrogenase system

Abstract

The irradiation with visible light of a photosensitizer dye like methylene blue was used to regenerate by electron transfer the oxidized form of a pyridine nucleotide coenzyme (NAD(+)). The process has been studied on a common enzymatic reaction: ethanol oxidation by alcohol-NAD(+) oxidoreductase immobilized on polyacrylamide gel or porous glass balls. In the experimental conditions used, the initial NAD(+) recycling rates were 2.33 x 10(4) cycles/h (polyacrylamide) and 3 x 10(4) cycles/h (glass balls). A total number of 49.5 x 10(4) cycles was obtained for 13 runs of 2 h. The enzyme immobilization strongly increased its stability: after 28 days at 20 degrees C, the residual activity was 25% of the initial value.

Cofactor Regeneration for Enzyme-Catalysed Synthesis

“…Photoexcitation by visible light accelerates the oxidation of NAD(P)H by several electron-transfer dyes (Chambers et al, 1974) and facilitates the regeneration of NAD(P) by catalytic quantities of PMS and methylene blue (Julliard and Le Petit, 1982;Julliard, Le Petit and Ritz, 1986). TTN for NAD have reached 1125.…”

NAD(H) recycling activity of an engineered bifunctional enzyme galactose dehydrogenase/lactate dehydrogenase

“…Economically, to maximize the involving of cofactors, regeneration and recycling of the coenzyme within the enzyme reactor is often required. Engineering to generate the NAD(H) in a reaction has been performed by using both electrochemical 6 and photosensitized electron transfer 7 . However, the most common methods used are based on enzymatic regeneration 8 , 9 .…”

A NAD(P)H oxidase mimic for catalytic tumor therapy via a deacetylase SIRT7-mediated AKT/GSK3β pathway

“…In this context, alcohol dehydrogenase (ADH), an enzyme reliant on the oxidized incarnation of NAD + for its catalytic vigor, was utilized. 58 This orchestrated reaction paradigm involved the conjunction of ADH-catalyzed oxidation of ethanol, culminating in the reduction of bioactive NAD + . Initially, the predominant oxidation of NADH was facilitated by C@Co, as evinced by the black trajectory in Fig.…”