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arXiv · 0804.1720

Charge transport in bacteriorhodopsin monolayers: The contribution of conformational change to current-voltage characteristics

Eleonora Alfinito·Lino Reggiani
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Abstract

When moving from native to light activated bacteriorhodopsin, modification of charge transport consisting of an increase of conductance is correlated to the protein conformational change. A theoretical model based on a map of the protein tertiary structure into a resistor network is implemented to account for a sequential tunneling mechanism of charge transfer through neighbouring amino acids. The model is validated by comparison with current-voltage experiments. The predictability of the model is further tested on bovine rhodopsin, a G-protein coupled receptor (GPCR) also sensitive to light. In this case, results show an opposite behaviour with a decrease of conductance in the presence of light.

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Eleonora Alfinito, Lino Reggiani. 2008-04-10. Charge transport in bacteriorhodopsin monolayers: The contribution of conformational change to current-voltage characteristics. https://doi.org/10.1209/0295-5075/85/68002

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