Actin polymerization under pressure: a theoretical study.

Maxim N Artyomov; Karl F Freed

doi:10.1063/1.2409928

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PubMed · 17228974

Actin polymerization under pressure: a theoretical study.

Maxim N Artyomov·Karl F Freed

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Abstract

An extended Flory-Huggins-type equilibrium polymerization theory for compressible systems is used to describe experimental data for the unusual pressure and temperature dependence of the equilibrium polymerization of G-actin to F-actin. The calculations provide rich insights into the reaction mechanism and the thermodynamics of actin polymerization at the molecular level. Volume changes associated with individual steps of the mechanism are calculated to be DeltaVactiv=(s1*-s1)upsilon0=+1553 mlmol for the activation reaction, DeltaVdim=(s2-s1*)upsilon0=-3810 mlmol for dimerization, and DeltaVprop=(sP-s1)upsilon0=+361 mlmol for the propagation reaction, where s1upsilon0, s1*upsilon0, s2upsilon0, and sPupsilon0 are the monomer volumes in the G-actin monomer, the activated G-action, the dimer, and higher polymers, respectively. Comparison with experimental measurements is made, and discrepancies are discussed.

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Actin Cytoskeleton Actins Binding Sites Biopolymers Computer Simulation Models, Chemical Models, Molecular Multiprotein Complexes Pressure Protein Binding Protein Conformation Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Maxim N Artyomov, Karl F Freed. 2007-01-14. Actin polymerization under pressure: a theoretical study.. https://doi.org/10.1063/1.2409928

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