FIGURE 3.

Purified acrolein-reducing enzyme catalyzes the reduction of the α,β-unsaturated bond but not the aldehyde moiety of acrolein. A, two theoretical NADPH-dependent reduction pathways of acrolein. B, using NADPH as a reductant, acrolein was metabolized for the indicated length of time with the purified enzyme. After this reaction, the product was subjected to DNPH derivatization and subsequent HPLC analysis. DNPH reacts with the aldehyde group of acrolein and propionaldehyde but not the alcohol group of allyl alcohol.