An affibody in complex with a target protein: Structure and coupled folding.
2003 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 100, no 6, 3185-3190 p.Article in journal (Refereed) Published
Combinatorial protein engineering provides powerful means for functional selection of novel binding proteins. One class of engineered binding proteins, denoted affibodies, is based on the three-helix scaffold of the Z domain derived from staphylococcal protein A. The Z(SPA-1) affibody has been selected from a phage-displayed library as a binder to protein A. Z(SPA-1) also binds with micromolar affinity to its own ancestor, the Z domain. We have characterized the Z(SPA-1) affibody in its uncomplexed state and determined the solution structure of a Z:Z(SPA-1) protein-protein complex. Uncomplexed Z(SPA-1) behaves as an aggregation-prone molten globule, but folding occurs on binding, and the original (Z) three-helix bundle scaffold is fully formed in the complex. The structural basis for selection and strong binding is a large interaction interface with tight steric and polar/nonpolar complementarity that directly involves 10 of 13 mutated amino acid residues on Z(SPA-1). We also note similarities in how the surface of the Z domain responds by induced fit to binding of Z(SPA-1) and Ig Fc, respectively, suggesting that the Z(SPA-1) affibody is capable of mimicking the morphology of the natural binding partner for the Z domain.
Place, publisher, year, edition, pages
2003. Vol. 100, no 6, 3185-3190 p.
protein engineering, protein-protein interactions, molecular recognition, NMR spectroscopy, induced fit
Other Industrial Biotechnology
IdentifiersURN: urn:nbn:se:kth:diva-8642DOI: 10.1073/pnas.0436086100ISI: 000181675200039OAI: oai:DiVA.org:kth-8642DiVA: diva2:14020
Uppdaterad från "In press" till published: 20100924.
QC 201009242005-11-082005-11-082010-09-24Bibliographically approved