Work

Interfacial Protein–Protein Associations

Year: 2013

Type: article

Abstract: While traditional models of protein adsorption focus primarily on direct protein-surface interactions, recent findings suggest that protein-protein interactions may play a central role. Using high-throughput intermolecular resonance energy transfer (RET) tracking, we directly observed dynamic, protein-protein associations of bovine serum albumin on polyethylene glycol modified surfaces. The associations were heterogeneous and reversible, and associating molecules resided on the surface for longer times. The appearance of three distinct RET states suggested a spatially heterogeneous surface - with areas of high protein density (i.e., strongly interacting clusters) coexisting with mobile monomers. Distinct association states exhibited characteristic behavior, i.e., partial-RET (monomer-monomer) associations were shorter-lived than complete-RET (protein-cluster) associations. While the fractional surface area covered by regions with high protein density (i.e., clusters) increased with increasing concentration, the distribution of contact times between monomers and clusters was independent of solution concentration, suggesting that associations were a local phenomenon, and independent of the global surface coverage.

Source: Biomacromolecules

DOI: 10.1021/bm401302v

Authors: Blake B. Langdon, Mark Kastantin, Robert Walder, Daniel K. Schwartz

Institution: University of Colorado Boulder

Language: English

Topic: Polymer Surface Interaction Studies

Subfield: Surfaces, Coatings and Films

Field: Materials Science

Domain: Physical Sciences

Open Access status: green

Funders: National Institutes of Health, National Institute of Biomedical Imaging and Bioengineering, Basic Energy Sciences

Awards: G1166162248, Tools to Connect Protein Conformations, Dynamics, and Associations, G8727747407, G8970974842