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Conductance of a biomolecular wire.

ABSTRACT: Carotenoids (Car) act as "wires" that discharge unwanted electrons in the reaction center of higher plants. One step in this "side-path" electron conduction is thought to be mediated by Car oxidation. We have carried out direct measurements of the conductance of single-Car molecules under potential control in a membrane-mimicking environment, and we found that when Car are oxidized conductance is enhanced and the electronic decay constant (beta) is decreased. However, the neutral molecule may already be conductive enough to account for observed electron transfer rates.

SUBMITTER: Visoly-Fisher I

PROVIDER: S-EPMC1482640 | biostudies-literature | 2006 Jun

REPOSITORIES: biostudies-literature

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Conductance of a biomolecular wire.

Visoly-Fisher Iris I Daie Kayvon K Terazono Yuichi Y Herrero Christian C Fungo Fernando F Otero Luis L Durantini Edgardo E Silber Juana J JJ Sereno Leonides L Gust Devens D Moore Thomas A TA Moore Ana L AL Lindsay Stuart M SM

Proceedings of the National Academy of Sciences of the United States of America 20060525 23

Carotenoids (Car) act as "wires" that discharge unwanted electrons in the reaction center of higher plants. One step in this "side-path" electron conduction is thought to be mediated by Car oxidation. We have carried out direct measurements of the conductance of single-Car molecules under potential control in a membrane-mimicking environment, and we found that when Car are oxidized conductance is enhanced and the electronic decay constant (beta) is decreased. However, the neutral molecule may al ...[more]

PMID: 16728508

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