Detecting conformational change by current transport in proteins: The case of bacteriorhodopsin monolayers
نویسندگان
چکیده
Recent experiments on the light receptor bacteriorhodopsin have revealed the protein conductive properties and connected them to its sensing action. In particular it was shown that the super-Ohmic I-V characteristic acquired in dark, changes in the presence of green light, with an enhancement of current at increasing bias values. Here we propose a current transport model for proteins able to reproduce experimental data, mainly the dependence of current on their three dimensional (tertiary) structure. The model is based on a resistance network model and implements a tunneling mechanism of charge transfer between the aminoacids constituting the protein.
منابع مشابه
Charge transport in bacteriorhodopsin monolayers: The contribution of conformational change to current-voltage characteristics
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. ...
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