Use of isotope effects to elucidate enzyme mechanisms.

  title={Use of isotope effects to elucidate enzyme mechanisms.},
  author={W. Wallace Cleland},
  journal={CRC critical reviews in biochemistry},
  volume={13 4},
The chemical bond breaking steps are normally not rate limiting for enzymatic reactions. However, comparison of deuterium and tritium isotope effects on the same reaction, especially when coupled with 13C isotope effects for the same step measured with deuterated as well as unlabeled substrates, allows calculation of the intrinsic isotope effects on the bond breaking steps and thus a determination of the commitments to catalysis for the reactants. The variation in observed isotope effects as a… CONTINUE READING