Aldehyde Dehydrogenase from Yeast, 25u

Aldehyde dehydrogenase belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with NAD+ or NADP+ as acceptor. Aldehyde dehydrogenase oxidizes a number of aliphatic and aromatic aldehydes. Acetyl-GSH is not hydrolyzed. Aldehyde dehydrogenase is a tetramer and has several different isoforms. The enzyme tested in 0.01 M pyrophosphate buffer shows a sharp optimum around pH 9.3 with acetaldehyde as substrate. Potassium ions and cysteine are essential for the enzyme′s activity. Rubidium or NH4+ can be substituted for K+, and glutathione for cysteine. Lithium, Na+, and Cs+ inhibit the reaction. Aldehyde dehydrogenase is inhibited by propylurea, crotonaldehyde, n-propyl isocyanate, cyclohexyl isocyanate, 1-n-propyl-1-[(4-chlorophenyl)sulphonyl]-3-n-propylurea, and 1-methyl-1-[(4-chlorophenyl)sulphonyl]-3-n-propylurea. The enzyme may be utilized to quantitate aldehydes present in blood.