Tetrahymena ribozyme, counterion condensation

Heilman-Miller, S. L., Thirumalai, D., and Woodson, S. A. (2001). Role of counterion condensation in folding of the Tetrahymena ribozyme. I. Equilibrium stabilization by cations. J. Mol. Biol. 306, 1157—1166. 

To explain the folding characteristics of Tetrahymena ribozyme, a simple generalization of counterion condensation model was proposed [108, 109], In this two state model, equilibrium is considered between condensed and free counterions [108]. The chemical potential for each phase is approximately calculated as follows. If the volume fraction occupied by the counterions is denoted by < ), then the chemical potential of the free counterions is [108]... 

S. L. Heilman-Miller, D. Thirumalai, andS. A. Woodson,/. Molec. Biol., 306,1157 (2001). Role of Counterion Condensation in Folding of the Tetrahymena Ribozyme. I. Equilibrium Stabilization by Cations. 

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