Binary and ternary aggregation within tethered protein constructs.

Wei Yuan Yang; Martin Gruebele

doi:10.1529/biophysj.105.075846

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Binary and ternary aggregation within tethered protein constructs.

Wei Yuan Yang·Martin Gruebele

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Abstract

The free energy per monomer of a protein aggregate varies with the number of participating monomers n. The change of this free energy with aggregate size, DeltaDeltaG(n), is difficult to determine by sedimentation or concentration studies. We introduce a kinetic approach to quantitate the free energy of aggregates in the presence of tethers. By linking the protein U1A into dimers and trimers, a high effective concentration of the monomers is achieved, together with exact size control of the aggregates. We found that the free energy of the aggregate relative to the native monomer reached a maximum for n = 2, and decreased by DeltaDeltaG(2) = -3.1 kT between dimer and trimer.

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Dimerization Guanidine Kinetics Models, Molecular Protein Binding Protein Denaturation Protein Folding Proteins Thermodynamics Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Wei Yuan Yang, Martin Gruebele. 2006-01-20. Binary and ternary aggregation within tethered protein constructs.. https://doi.org/10.1529/biophysj.105.075846

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