Molecular basis of a million-fold affinity maturation process in a protein-protein interaction
AuthorsBonsor, Daniel A.
Pierce, Brian G.
Buonpane, Rebecca A.
Kranz, David M.
Sundberg, Eric J.
UMass Chan AffiliationsProgram in Bioinformatics and Integrative Biology
Department of Biochemistry and Molecular Pharmacology
*Protein Interaction Mapping
Protein Structure, Quaternary
Receptors, Antigen, T-Cell
Amino Acids, Peptides, and Proteins
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AbstractProtein engineering is becoming increasingly important for pharmaceutical applications where controlling the specificity and affinity of engineered proteins is required to create targeted protein therapeutics. Affinity increases of several thousand-fold are now routine for a variety of protein engineering approaches, and the structural and energetic bases of affinity maturation have been investigated in a number of such cases. Previously, a 3-million-fold affinity maturation process was achieved in a protein-protein interaction composed of a variant T-cell receptor fragment and a bacterial superantigen. Here, we present the molecular basis of this affinity increase. Using X-ray crystallography, shotgun reversion/replacement scanning mutagenesis, and computational analysis, we describe, in molecular detail, a process by which extrainterfacial regions of a protein complex can be rationally manipulated to significantly improve protein engineering outcomes.
J Mol Biol. 2011 Aug 12;411(2):321-8. doi: 10.1016/j.jmb.2011.06.009. Link to article on publisher's site
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/25882
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