Interactions of superoxide anion with enzyme radicals: kinetics of reaction with lysozyme tryptophan radicals and corresponding effects on tyrosine electron transfer.

@article{Santus2000InteractionsOS,
  title={Interactions of superoxide anion with enzyme radicals: kinetics of reaction with lysozyme tryptophan radicals and corresponding effects on tyrosine electron transfer.},
  author={Ren{\'e} Santus and L. K. Patterson and Gordon L. Hug and M Beth Bazin and Jean Claude Mazi{\`e}re and Patrice Morli{\`e}re},
  journal={Free radical research},
  year={2000},
  volume={33 4},
  pages={383-91}
}
The kinetics of O2*- reaction with semi-oxidized tryptophan radicals in lysozyme, Trp*(Lyz) have been investigated at various pHs and conformational states by pulse radiolysis. The Trp*(Lyz) radicals were formed by Br2*- oxidation of the 3-4 exposed Trp residues in the protein. At pH lower than 6.2, the apparent bimolecular rate is about 2 x 10(8) M(-1) s(-1); but drops to 8 x 10(7) M(-1) s(-1) or less above pH 6.3 and in CTAC micelles. Similarly, the apparent bimolecular rate constant for the… CONTINUE READING