The enhancement of the mutagenic effect of ultraviolet radiation inEscherichia coli by caffeine and acriflavine

Ultraviolet-Induced Mutation and Dna Repair

“…This is especially doubtful in the case of acriflavine which causes considerable enhancement of the lethal effect (but not of the mutagenic effect) of ultraviolet light in excision-defective (Hcr-) strains, as shown by Harm (101 ) and Vechet (99). This is especially doubtful in the case of acriflavine which causes considerable enhancement of the lethal effect (but not of the mutagenic effect) of ultraviolet light in excision-defective (Hcr-) strains, as shown by Harm (101 ) and Vechet (99).…”

GENETIC DAMAGE INDUCED BY 254nm ULTRAVIOLET LIGHT IN ESCHERICHIA COLI: 8‐METHOXYPSORALEN AS PROTECTIVE AGENT AND REPAIR INHIBITOR

“…At comparable molarities it is less efficient that acnflavine although this is offset by its negli- gible toxicity. Since it has no effect whatever on the Hcr-strain, it differs from acriflavine which may have a substantial effect on survival (but not mutation or survival of irradiated phage) in UUY (Hcr-) strains [8,9]. 8-MOP may thus be a more specific inhibitor of excision-repair than acriflavine.…”

Evidence for repair of ultraviolet‐induced damage in Cystobacter species (Myxobacterales)

“…From investigations with E. coli several repair inhibitors are known, which mainly inhibit excision repair (CLARKE and SHAN-KEL 1974, GRIGG 1972, HARM 1967, WITKIN 1969. Acriflavine inhibits both excision repair and post-replication repair in E. coli (HARM 1967, VECHET 1968, WITKIN 1969, WITKIN and FARQUHARSON 1969. Caffeine (8 mM) and coumarin (2-4 mM) inhibit only excision repair (GRIGG 1972).…”