Abstract
L-ethionine, a hepatocarcinogen, exhibited a strong bio-antimutagenic effect against spontaneous mutation in Ames' Salmonella strains as well as in a Bacillus subtilis mutator strain whose mutator activity was due to an error-prone DNA replicating enzyme. The bio-antimutagenic effect of L-ethionine was completely abolished by the presence of L-methionine, but not by D-methionine, suggesting that genetic effect of L-ethionine was expressed through its interaction with L-methionine metabolism in the treated cells.
