Photocatalytic fixation of carbon dioxide in oxoglutaric acid using isocitrate dehydrogenase and cadmium sulphide
Abstract
Photocatalytic fixation of CO2 in oxoglutaric acid to yield isocitric acid was investigated with the use of isocitrate dehydrogenase as a catalyst, methyl viologen as an electron mediator and cadmium sulphide as a photocatalyst. The rate of the isocitric acid production depended on the concentration of oxoglutaric acid and methyl viologen, and the rate equation to meet these findings was derived. The Michaelis–Menten constant determined by using this equation (Km1 and Km2) was 23.9 mmol dm–3 for the substrate and 0.030 mmol dm–3 for the mediator, suggesting that the electron transfer between isocitrate dehydrogenase and the substrate is the rate-determining step.