Open AccessInduction of an abortive and futile DNA repair process inE.coliby the antitumor DNA bifunctional intercalator, ditercalinium: role inpolAin death induction
Author(s) -
Bernard Lambert,
Bernárd P. Roques,
Jean-Bernard Le Pecq
Publication year - 1988
Publication title -
nucleic acids research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 9.008
H-Index - 537
eISSN - 1362-4954
pISSN - 0305-1048
DOI - 10.1093/nar/16.3.1063
Subject(s) - biology , dna , dna repair , dna polymerase , microbiology and biotechnology , polymerase , dna clamp , cytotoxic t cell , dna damage , escherichia coli , bifunctional , biochemistry , in vitro , rna , gene , reverse transcriptase , catalysis
Ditercalinium, an antitumor bifunctional intercalator which forms a high affinity reversible complex with DNA, was found to be specifically cytotoxic for polA and lig7 E. coli strains. In the polA strain, the cytotoxic effect of ditercalinium was suppressed by the uvrA mutation. DNA single strand breaks accumulated in presence of ditercalinium at high temperature in lig7 strains but not in polA strains. Ditercalinium caused no DNA synthesis inhibition although it was able to induce SOS functions. It is proposed that the ditercalinium DNA complex because of its non covalent nature acts as a dummy lesion for the UV repair system in E. coli leading to a futile and abortive repair process. Polymerase I appears to be required to prevent the malfunctioning of a DNA repair process triggered by molecules forming non covalent complex with DNA.