NMR Structure of the IQ-modified Dodecamer CTCG[IQ]GCGCCATC

DNA sequence modulates the conformation of the food mutagen 2-amino-3-methylimidazo[4,5-f]quinoline in the recognition sequence of the NarI restriction enzyme

DNA (5'-D(*DCP*DTP*DCP*DGP*DGP*DCP*DGP*DCP*DCP*DAP*DTP*DC)-3')

DNA (5'-D(*DGP*DAP*DTP*DGP*DGP*DCP*DGP*DCP*DCP*DGP*DAP*DG)-3')

The unmodified oligodeoxynucleotide 5'-d(GATGGCGCCGAG)-3' was obtained from the Midland Certified Reagent Company, and had been purified by anion exchange chromatography. The IQ-adducted oligodeoxynucleotide 5'-d(CTCGXCGCCATC)-3' was synthesized and purified as described in paper by Elmquist, C. Eric[ JACS, vol. 126, No.36, 2004].

The structure was determined using standard 2D homonuclear techniques

simulated annealing restrained molecular dynamics

0.7mM modified duplex, 10mM phosphate buffer with 0.1M NaCl and 0.05mM Na2EDTA (pH 7.0), D2O
10mM phosphate buffer with 0.1M NaCl and 0.05mM Na2EDTA (pH 7.0), D2O

0.7mM modified duplex, 10mM phosphate buffer with 0.1M NaCl and 0.05mM Na2EDTA (pH 7.0), 90% H2O and 10% D2O
10mM phosphate buffer with 0.1M NaCl and 0.05mM Na2EDTA (pH 7.0), 90% H2O and 10% D2O