DNA DAMAGE AND PROPHAGE INDUCTION AND TOXICITY OF NITROFURANTOIN IN ESCHERICHIA-COLI AND VIBRIO-CHOLERAE CELLS

Repair-deficient and repair-proficient strains of E. coli K12 were sensitive to nitrofurantoin treatment to varying degrees with the double mutant strain (uvrA 6, recA 13) being most sensitive. Ultraviolet absorption data and thermal chromatography through a hydroxyapatite column revealed that nitrofurantoin treatment of V. cholerae strain OGAWA 154 produced a maximal amount of 55% reversibly bihelical DNA at a nitrofurantoin dose of 120 μg/ml/h, which indicated the formation of inter-strand cross-links in DNA. Nitrofurantoin also produced prophage-λ induction in E. coli K12 strain GY 5027: envA, uvrB, ampA 1, strA (λ), in a dose-dependent manner, the maximum induction being highly significant (P < 0.001). Previously published mutation data coupled with the prophage induction data presented here suggest that the genotoxic properties of nitrofurantoin are mediated through the SOS pathway. © 1990.