Research Articles

Electron tunneling paths in proteins

Science  26 Jun 1987:
Vol. 236, Issue 4809, pp. 1647-1652
DOI: 10.1126/science.3603005


One of the crucial issues in biological electron transfer is the determination of the role of spatially intermediate amino acid residues in controlling or directing the electronic tunneling interaction between redox sites. A quantum path integral Monte Carlo method is developed for the analysis of electronic tunneling pathways in a highly structured environment. This path integral method is applied to intramolecular electron transfer in a ruthenium-modified myoglobin that contains a tryptophan in the "line-of-flight." A principal result is the identification of the relevant cylindrical zone swept out by the tunneling electron.