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PubMed · 7604031

Alternate protein frameworks for molecular recognition.

J Ku·P G Schultz
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Abstract

In an effort to determine whether proteins with structures other than the immunoglobulin fold can be used to mimic the ligand binding properties of antibodies, we generated a library from the four-helix bundle protein cytochrome b562 in which the two loops were randomized. Panning of this library against the bovine serum albumin (BSA) conjugate of N-methyl-p-nitrobenzylamine derivative 1 by phage display methods yielded cytochromes in which residues Trp-20, Arg-21, and Ser-22 in loop A and Arg-83 and Trp-84 in loop B were conserved. The individual mutants, which fold into native-like structure, bind selectively to the BSA-1 conjugate with micromolar dissociation constants (Kd), in comparison to a monoclonal antibody that binds selectively to 1 with a Kd of 290 nM. These and other antibody-like receptors may prove useful as therapeutic agents or as reagents for both intra- and extracellular studies.

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Amino Acid SequenceArginineBacteriophagesBase SequenceCircular DichroismConserved SequenceCytochrome b GroupDatabases, FactualEnzyme-Linked Immunosorbent AssayEscherichia coli ProteinsGenetic VectorsHemerythrinModels, StructuralMolecular Sequence DataMutagenesis, Site-DirectedOligodeoxyribonucleotidesProtein BiosynthesisProtein FoldingProtein Structure, SecondaryProteinsRandom AllocationRecombinant ProteinsSerineSerum Albumin, BovineTryptophanComparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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J Ku, P G Schultz. 1995-07-03. Alternate protein frameworks for molecular recognition.. https://doi.org/10.1073/pnas.92.14.6552

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