An aldehyde reduction enzyme has been purified from the cytosol of the tapeworm, Moniezia expansa, by chromatofocusing and Reactive-Red chromatography. The enzyme is monomeric (subunit 34 kDa) and can utilise NADH and NADPH as co-factors. Substrates of the enzyme include alkanals, alka-2,4-dienals and alk-2-enals, established secondary products of lipid peroxidation. The enzyme reduced methylglyoxal, another possible natural substrate (M. expansa lacks glyoxalase I activity). The parasite enzyme may help form a final line of defence against cytotoxic aldehydes arising from host immune initiated lipid peroxidation.
