TYPES OF MUTATIONS INDUCED BY GLYOXAL, A MAJOR OXIDATIVE DNA-DAMAGE PRODUCT, IN SALMONELLA-TYPHIMURIUM

We have analyzed the types of mutations induced by glyoxal, a major ox idative DNA-damage product, in Salmonella typhimurium. A set of six st rains, TA7001 to TA7006, was used to detect base-pair substitutions, a nd the TA98 strain was employed to detect frameshift mutations. Glyoxa l did not induce mutations at A:T base pairs. The majority of the muta tions induced by glyoxal were base-pair substitutions at G:C base pair s, and a small level of frameshift mutations was detected in the TA98 strain.