The action of British anti-lewisite (BAL) on enzyme systems

Abstract

The effect of 2:3-dimercap-topropanol (BAL) on the following enzymes was examined: polyphenol oxidase, carbonic anhydrase, catalase, peroxidase, cytochrome oxidase, aldehyde mutase, phosphorylase, gly-oxalase, hexokinase, pyrophosphatase, succinic dehydrogen-ase, xanthine oxidase, d-amino-acid oxidase, creatine phos-phokinase, cholinesterase (serum), cholinesterase (brain), pepsin, trypsin, papain, zymohexase, glycolysis system. Of the 7 enzymes inhibited, 4 (polyphenol oxidase, carbonic anhydrase; catalase, and peroxidase) were known to be metal-containing enzymes. The inhibition of glyoxalase was due to competition with glutathione, the activator of the enzyme. Aldehyde mutase and phosphprylase were also inhibited. The inhibition of mushroom polyphenol oxidase by BAL was reversed by addition of excess of Cu salt. This inhibition was due to the formation of an insoluble cupric-BAL compound. The activity of hexokinase in the presence of sub-optimal conc, of Mg++ was diminished by BAL, an effect immediately reversed by addition of excess Mg++. BAL was oxidized by the cytochrome system without any effect on the activity of the latter. BAL was considered as a potent inhibitor of metal-containing enzymes with the exception of the cytochrome system.