Mode of mutagenic action of 4-benzoylamido- and 4-acetamido-4-carboxamido-n(N-nitroso)-butylcyanamide.

The mode of mutagenic action of 4-benzoylamido- and 4-acetamido- 4-carboxamido-n(N-nitroso)-butylcyanamide (BCNBC, ACNBC) was studied using Escherichia coli K12 strains. The strains carrying defects in DNA-repair mechanism, AB2463 (recA) and P3478 (polA) were more sensitive than their parent strains to both compounds, while AB1886 (uvrA) showed the same sensitivity as the parental strain. About 90% of tryptophan revertants from BE1043 (trpambphoamb) by both compounds were due to mutation in suppressor genes. Suppressor analysis by using BE1047 (trpambphooch) revealed that the most frequently occurring reversion was due to a mutation in suppressor gene, supE. This implies that these two alkylnitrosocyanamides predominantly induce GC leads to AT transition.