Multiplexed sorting of libraries on libraries: a novel method for empirical protein design by affinity-driven phage enrichment on synthetic peptide arrays.

Chemically synthesized peptide arrays on planar cellulose carriers are proposed as libraries of ligands suitable for the multiplexed simultaneous capture of peptide-specific acceptor proteins from a large randomly mutagenized library of acceptor proteins presented on bacteriophage M13 particles. This experimental set-up can be exploited to rapidly screen for individual new, distinct binding partners from two complementary libraries (two-dimensional screening). The technical feasibility of this empirical protein design approach was demonstrated with calmodulin as an aceptor protein using an array of mastoparan variants for multiplexed phage affinity enrichment.