DNA-binding mechanism of spiropyran photoswitches: the role of electrostatics.

The binding mechanism of the protonated open form of three spiropyran derivatives into a 12-mer (poly-dAT)2 has been unveiled by means of computational methods. It is found that the electrostatic term in the probe:DNA binding energy, modulates the binding mode, providing new guidelines for the design of spiropyran photoswitches with specific binding modes to DNA.