NMR studies of a plant flavonoid--DNA oligonucleotide complex.

A structural model of the solution complex between a flavonoid and a DNA dodecamer containing the E. coli wild-type lac promoter sequence (TATGTT) was obtained using simulated annealing for refinement. The distance constraints were derived from NOESY NMR spectra. The minor groove binding of this flavonoid displays possible hydrogen bonds to the DNA, and these can take part in complex formation. This work is the first description of how a molecule of this class of natural compounds may interact with DNA.