title: The Escherichia coli DNA repair protein UvrA can re-associate with the UvrB: aflatoxin B1-DNA complex in vitro.
abstract: The UvrA and UvrB proteins form part of the UvrABc endonuclease, which is responsible for nucleotide excision repair in Escherichia coli. Using a mobility shift gel assay we have studied the binding of UvrA dimer, UvrB monomer and UvA(2)B trimer complexes with 40, 50 and 136 bp (32)P-end-labelled DNA fragments adducted with aflatoxin B(1). UvrA was shown to re-associate with adduct specific UvrB: DNA complexes, a phenomenon which could be reversed by the addition of 500 mM potassium chloride or anti-UvrA anti-sera. Re-association was shown to be UvrA concentration dependent. Re-association of UvrA(2)B to the UvrB:DNA complex was not seen. We have also shown that the UvrB:DNA complex, in the case of aflatoxin B(1), is extremely stable with a half-life excess of 400 min and that fragment termini are not a specific substrate for UvrA binding.
authors.affiliation: The Jack Birch Unit for Environmental Carcinogenesis, Biology Department, University of York, Heslington, UK.
authors.forename: J M
authors.initials: JM
authors.lastname: Allan
authors.forename: M N
authors.initials: MN
authors.lastname: Routledge
authors.forename: R C
authors.initials: RC
authors.lastname: Garner
mesh_terms: D000251:Adenosine Triphosphatases / Q000302:isolation & purification / Q000378:metabolism*; D000348:Aflatoxins / Q000097:blood / Q000302:isolation & purification / Q000378:metabolism*; D001426:Bacterial Proteins / Q000302:isolation & purification / Q000378:metabolism*; D004247:DNA / Q000138:chemical synthesis / Q000302:isolation & purification / Q000378:metabolism*; D004249:DNA Damage; D004265:DNA Helicases; D004260:DNA Repair; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D029968:Escherichia coli Proteins; D005091:Exons; D016158:Genes, p53; D006801:Humans; D007700:Kinetics; D046911:Macromolecular Substances; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis / Q000302:isolation & purification / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011485:Protein Binding; D016335:Zinc Fingers
chemical_list: D000348:Aflatoxins; D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D046911:Macromolecular Substances; D009838:Oligodeoxyribonucleotides; C058093:UvrB protein, E coli; D004247:DNA; C068631:UvrA protein, E coli; D000251:Adenosine Triphosphatases; D004265:DNA Helicases