Question

monitoring a reaction catalyzed by an NAD-dependent enzyme, a biochemist noticed that the peak of absorbance at 340nm gradually increases. is this reaction procesding towards the formation of NAD+ or NADH?

QUESTION 20 Monitoring a reaction catalyzed by an NAD-dependent enzyme, a biochemist notices that the peak of absorbance at 340 nm gradually increases. Is the reaction proceeding towards the formation of NAD+ or NADH?

Answer 1

NADH can absorbs light of 340 nm wavelength while NAD+ has no absorbance. As mentioned in the question at 340 nm absorbance is increasing that means NADH concentration is increasing (since absorbance is directly proportional to the concentration). Hence the reaction is producing NADH.