Femtochemistry in enzyme catalysis: DNA photolyase

Ya-Ting Kao, Chaitanya Saxena, Lijuan Wang, Aziz Sancar, Dongping Zhong*

*Corresponding author for this work

Research output: Contribution to journalReview article

34 Scopus citations

Abstract

Photolyase uses light energy to split UV-induced cyclobutane pyrimidine dimers in damaged DNA. This photoenzyme encompasses a series of elementary dynamical processes during repair function from early photoinitiation by a photoantenna molecule to enhance repair efficiency, to in vitro photoreduction through aromatic residues to reconvert the cofactor to the active form, and to final photorepair to fix damaged DNA. The corresponding series of dynamics include resonance energy transfer, intraprotein electron transfer, and intermolecular electron transfer, bond breaking-making rearrangements and back electron return, respectively. We review here our recent direct studies of these dynamical processes in real time, which showed that all these elementary reactions in the enzyme occur within subnanosecond timescale. Active-site solvation was observed to play a critical role in the continuous modulation of catalytic reactions. As a model system for enzyme catalysis, we isolated the enzyme-substrate complex in the transition-state region and mapped out the entire evolution of unmasked catalytic reactions of DNA repair. These observed synergistic motions in the active site reveal a perfect correlation of structural integrity and dynamical locality to ensure maximum repair efficiency on the ultrafast time scale.

Original languageEnglish
Pages (from-to)32-44
Number of pages13
JournalCell Biochemistry and Biophysics
Volume48
Issue number1
DOIs
StatePublished - 1 May 2007

Keywords

  • Cyclobutane pyrimidine dimer (CPD)
  • DNA photolyase
  • DNA repair
  • Electron transfer (ET)
  • Enzyme catalysis
  • Femtochemistry
  • Photoinitiation
  • Photoreduction
  • Photorepair
  • Resonance energy transfer (RET)
  • Solvation dynamics

Fingerprint Dive into the research topics of 'Femtochemistry in enzyme catalysis: DNA photolyase'. Together they form a unique fingerprint.

  • Cite this