Growth inhibitory properties of aromatic alpha-ketoaldehydes toward bacteria and yeast. Comparison of inhibition and glyoxalase I activity.

The alpha-ketoaldehydes methylglyoxal and substituted phenylglyoxals are similar in their abilities to inhibit the growth of Escherichia coli and yeast. When logarithmically growing cells are added to media containing 0.3-1 mM alpha-ketoaldehyde, growth stops for several hours, after which normal growth resumes. The period of growth inhibition does not appear to show any correlation with the ability of glyoxalase I to detoxify these alpha-ketoaldehydes. E. coli and yeast glyoxalase I show markedly different substrate specificities. For example, although both enzymes show broad specificity for both aliphatic and aromatic alpha-ketoaldehydes, 2,4,6-trimethylphenylglyoxal is a substrate for the E. coli enzyme but not for the yeast enzyme. Nevertheless, this alpha-ketoaldehyde inhibits the growth of both E. coli and yeast, similar to the other alpha-ketoaldehydes. Enzymes other than glyoxalase I must play a major role in the metabolism of these alpha-ketoaldehydes during the period of growth inhibition.