title: Inhibition of Eco RI action by polynucleotides. A characterization of the non-specific binding of the enzyme to DNA.
abstract: The cleavage of the plasmid pBR322 by the restriction endonuclease Eco RI has been studied in the presence of various polynucleotides and the double stranded octanucleotide d-(GGAATTCC) in order to clarify whether there is a preferential interaction of Eco RI with DNA sequences other than -GAATTC-. The steady state kinetic analysis shows that all polynucleotides investigated with the possible exception of poly-dG.poly-dC inhibit the cleavage competitively with Ki values in the range of 10(-4) to 10(-5) [M nucleotides]. The Ki of d-(GGAATTCC) is 1.5.10(-6) [M nucleotides], indicating that the specific binding is approx. 2 orders of magnitude stronger than non-specific binding.
mesh_terms: D004262:DNA Restriction Enzymes / Q000378:metabolism*; D004269:DNA, Bacterial; D004926:Escherichia coli; D007700:Kinetics; D009838:Oligodeoxyribonucleotides / Q000494:pharmacology; D010957:Plasmids; D011089:Polydeoxyribonucleotides / Q000494:pharmacology*; D011485:Protein Binding; D013329:Structure-Activity Relationship
chemical_list: D004269:DNA, Bacterial; D009838:Oligodeoxyribonucleotides; D011089:Polydeoxyribonucleotides; D004262:DNA Restriction Enzymes