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. 1988 Apr;53(4):617–621. doi: 10.1016/S0006-3495(88)83140-0

Nonlinear Voltage Dependence of the Light-Driven Proton Pump Current of Bacteriorhodopsin

D Braun, N A Dencher, A Fahr, M Lindau, M P Heyn
PMCID: PMC1330234  PMID: 19431722

Abstract

The light-driven proton pump current generated by bacteriorhodopsin reconstituted in asymmetric planar bilayer membranes was investigated. The current-voltage dependence was found to be nonlinear and can be approximated by an exponential at least below +50 mV. The current changed e-fold when the membrane potential was changed by 80 mV. The voltage dependence was analyzed in terms of a barrier model. This analysis revealed an effective displacement of 0.63 elementary charges across the membrane during the rate-limiting step. Comparison of this value with the results from flash-induced photovoltage signals suggests that one proton is pumped per cycle.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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