Specific and non-specific complexes of DNA and photolyase are visualised by atomic force microscopy. As a substrate for photolyase a 1150 bp DNA restriction fragment was UV-irradiated to produce damaged sites at random positions. Comparison with a 735 bp undamaged DNA fragment made it possible to separate populations of specific and non-specific photolyase complexes on the 1150 bp fragment, relieving the need for highly defined substrates. Thus it was possible to compare DNA bending for specific and non-specific interactions. Non-specific complexes show no significant bending but increased rigidity compared to naked DNA, whereas specific complexes show DNA bending of on average 36°and higher flexibility. A model obtained by docking shows that photolyase can accommodate a 36°bent DNA in the vicinity of the active site.

doi.org/10.1093/nar/27.19.3875, hdl.handle.net/1765/56669
Nucleic Acids Research
Department of Molecular Genetics

Noort, J., Orsini, F., Eker, A., Wyman, C., de Grooth, B., & de Greve, J. (1999). DNA bending by photolyase in specific and non-specific complexes studied by atomic force microscopy. Nucleic Acids Research, 27(19), 3875–3880. doi:10.1093/nar/27.19.3875