Why Are DNA and Protein Electron Transfer So Different?

Published

Journal Article

The corpus of electron transfer (ET) theory provides considerable power to describe the kinetics and dynamics of electron flow at the nanoscale. How is it, then, that nucleic acid (NA) ET continues to surprise, while protein-mediated ET is relatively free of mechanistic bombshells? I suggest that this difference originates in the distinct electronic energy landscapes for the two classes of reactions. In proteins, the donor/acceptor-to-bridge energy gap is typically several-fold larger than in NAs. NA ET can access tunneling, hopping, and resonant transport among the bases, and fluctuations can enable switching among mechanisms; protein ET is restricted to tunneling among redox active cofactors and, under strongly oxidizing conditions, a few privileged amino acid side chains. This review aims to provide conceptual unity to DNA and protein ET reaction mechanisms. The establishment of a unified mechanistic framework enabled the successful design of NA experiments that switch electronic coherence effects on and off for ET processes on a length scale of multiple nanometers and promises to provide inroads to directing and detecting charge flow in soft-wet matter.

Full Text

Duke Authors

Cited Authors

  • Beratan, DN

Published Date

  • June 2019

Published In

Volume / Issue

  • 70 /

Start / End Page

  • 71 - 97

PubMed ID

  • 30726186

Pubmed Central ID

  • 30726186

Electronic International Standard Serial Number (EISSN)

  • 1545-1593

International Standard Serial Number (ISSN)

  • 0066-426X

Digital Object Identifier (DOI)

  • 10.1146/annurev-physchem-042018-052353

Language

  • eng