Molecular Life Sciences

Living Edition
| Editors: Robert D. Wells, Judith S. Bond, Judith Klinman, Bettie Sue Siler Masters, Ellis Bell

Direct Enzymatic Reversal of DNA Damage

  • F. Peter Guengerich
Living reference work entry



This is a category of DNA repair in which the chemical modification is removed directly from the DNA. Enzymes are capable of doing this without excising bases or nucleotides.


Other sections of this encyclopedia deal with major types of DNA repair, including base excision, nucleotide excision, and mismatch repair. However, another type of repair is also important and will be presented here. At least three important types of direct reversal of DNA damage are known.

Photoreversal is a photoinduced process that eliminates photoinduced dimers (Fig. 1). Historically, this was one of the first modes of DNA repair recognized and provided an early impetus for the importance of DNA repair in biological systems.


Relay System Reactive Cysteine Photoinduced Process Base Pair Mutation Cysteine Group 
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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Department of Biochemistry and Center in Molecular ToxicologyBiochemistry and Center in Molecular Toxicology, Vanderbilt University School of MedicineNashvilleUSA