Electron flow through biological molecules: does hole hopping protect proteins from oxidative damage?
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ABSTRACT:
SUBMITTER: Winkler JR
PROVIDER: S-EPMC4793975 | biostudies-literature | 2015 Nov
REPOSITORIES: biostudies-literature
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Electron flow through biological molecules: does hole hopping protect proteins from oxidative damage?
Winkler Jay R JR Gray Harry B HB
Quarterly reviews of biophysics 20151101 4
Biological electron transfers often occur between metal-containing cofactors that are separated by very large molecular distances. Employing photosensitizer-modified iron and copper proteins, we have shown that single-step electron tunneling can occur on nanosecond to microsecond timescales at distances between 15 and 20 Å. We also have shown that charge transport can occur over even longer distances by hole hopping (multistep tunneling) through intervening tyrosines and tryptophans. In this per ...[more]
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