Electroconformational coupling

In these equations, Pj and P2 are the two conformational states of the transport protein, and equilibrium constants (K) and rate constants (k) in an electric field are shown to be these constants in zero field multiplied by a nonlinear term that is the product of A Me and the electric field across the membrane, Em. The r in these equations is the apportionation constant and has a value between 0 and 1 (14). This property of a membrane protein has been explored, and a model called electroconformational coupling has been proposed to interpret data on the electric activation of membrane enzymes (13-17). A four-state membrane-facilitated transport model has been analyzed and shown to absorb energy from oscillating electric fields to actively pump a substrate up its concentration gradient (see the section entitled Theory of Electroconformational Coupling). 

Figure 5. Simulation of the ac-stimulated cation pumping of Figure 2 by the electroconformational coupling model The filled circles are experimental points and the solid lines are calculated curves according to reaction 9. (Reproduced with permission from reference 32. Copyright 1991.)...

The electroconformational coupling method measures the force acting on a cell by a nonuniform oscillating electric field. Depending on the frequency... 

Tsong, T. Y. Astumian, R. D. Electroconformational coupling and membrane protein function. Prog. Biophys. Mol. Biol. 50, 1-45. 

Tsong, T. Y. Electroconformational coupling A fundamental process of biomolecular electronics for signal transduction. In Molecular Electronics Hong, F., Ed. Plenum New York pp 83-95. 

Markin, V. S. Tsong, T. Y. Electroconformational coupling of ion transport in oscillating electric field Rectification versus pumping. Bioelectrochem. Bioenerg. 26, 251-276. 

Tsong TY, Liu D-S, Chauvin F. (1989). Electroconformational coupling (ECC) An electric field induced enzyme oscillation for cellular energy and signal transductions. Bioelectrochemistry and Bioenergetics 21 319—331. 

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