TY - JOUR
T1 - Model Studies of DNA Photorepair
T2 - Enthalpy of Cleavage of a Pyrimidine Dimer Measured by Photothermal Beam Deflection Calorimetry
AU - Scannell, Michael P.
AU - Yeh, Syun Ru
AU - Falvey, Daniel E.
PY - 1996/11
Y1 - 1996/11
N2 - The enzyme DNA photolyase mediates the repair of pyrimidine dimers. This repair step, a net retro [2+2] reaction, proceeds through either the cation or anion radical of the pyrimidine dimer. In order to understand how electron transfer makes the repair process possible, its energetics have been examined by photothermal beam deflection calorimetry, fluorescence quenching and quantum yield studies. The enthalpy for the cleavage reaction of cis-syn 1,3-dimethylthymine dimer itself was found to be -19 kcal/mol. In addition, from the redox potentials, the enthalpies for the cleavage reactions of the dimer cation radical and the anion radical were determined to be -19 kcal/mol and -28 kcal/mol, respectively.
AB - The enzyme DNA photolyase mediates the repair of pyrimidine dimers. This repair step, a net retro [2+2] reaction, proceeds through either the cation or anion radical of the pyrimidine dimer. In order to understand how electron transfer makes the repair process possible, its energetics have been examined by photothermal beam deflection calorimetry, fluorescence quenching and quantum yield studies. The enthalpy for the cleavage reaction of cis-syn 1,3-dimethylthymine dimer itself was found to be -19 kcal/mol. In addition, from the redox potentials, the enthalpies for the cleavage reactions of the dimer cation radical and the anion radical were determined to be -19 kcal/mol and -28 kcal/mol, respectively.
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U2 - 10.1111/j.1751-1097.1996.tb01832.x
DO - 10.1111/j.1751-1097.1996.tb01832.x
M3 - Article
C2 - 8931373
AN - SCOPUS:0030294543
SN - 0031-8655
VL - 64
SP - 764
EP - 768
JO - Photochemistry and Photobiology
JF - Photochemistry and Photobiology
IS - 5
ER -