Patch engineering: a general approach for creating proteins that have new binding activities.

Patch engineering is a technique for creating folded proteins that have new binding activities. Different protein scaffolds are used to present a patch of discontinuous residues on a folded-protein surface. By varying simultaneously the residues in these patches and displaying these mutant proteins on phage, one can select proteins that have new binding activities. Patch engineering is applicable to any protein fold. Novel proteins derived by this approach might replace antibodies in certain applications or provide lead molecules for the design of non-peptide analogues.