Format

Send to

Choose Destination
Biophys J. 2001 Aug;81(2):667-74.

Thermodynamics and kinetics of actin filament nucleation.

Author information

1
Center for Computational Biology, Washington University, St. Louis, Missouri. 63130-4899, USA. dsept@biomed.wustl.edu

Abstract

We have performed computer simulations and free energy calculations to determine the thermodynamics and kinetics of actin nucleation and thus identify a probable nucleation pathway and critical nucleus size. The binding free energies of structures along the nucleation pathway are found through a combination of electrostatic calculations and estimates of the entropic and surface area contributions. The association kinetics for the formation of each structure are determined through a series of Brownian dynamics simulations. The combination of the binding free energies and the association rate constants determines the dissociation rate constants, allowing for a complete characterization of the nucleation and polymerization kinetics. The results indicate that the trimer is the size of the critical nucleus, and the rate constants produce polymerization plots that agree very well with experimental results over a range of actin monomer concentrations.

PMID:
11463615
PMCID:
PMC1301543
DOI:
10.1016/S0006-3495(01)75731-1
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center