Computational Assignment of the Histidine Protonation State in (6-4) Photolyase Enzyme and Its Effect on the Protonation Step

  title={Computational Assignment of the Histidine Protonation State in (6-4) Photolyase Enzyme and Its Effect on the Protonation Step},
  author={Hisham M. Dokainish and Akio Kitao},
  journal={ACS Catalysis},
The initial step to resolving the controversy regarding the repair mechanism of the pyrimidine (6-4) pyrimidone photoproduct DNA lesion is to determine the protonation state of the two conserved active site histidine residues (His365 and His369 in Drosophila melanogaster) in the (6-4) photolyase enzyme ((6-4) PHR). Both His residues were experimentally determined to be crucial for catalysis. Most previous theoretical studies assumed the presence of protonated His365 in the active site, which… 

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  • 2011
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