Geometry and expression drive yeast biopanning

Yeast surface display is an effective tool for the discovery and evolution of ligands for diagnostics and therapeutics. Ligand selections are often carried out using recombinant soluble domains of transmembrane proteins, which often contain features that are inaccurate relative to the true membrane-bound cellular target. As such, lack of translatability of lead clones is a common issue. Ligand selections against membrane-bound target can mitigate this problem. Stern and colleagues thoroughly examine the impacts of washing and incubation conditions, ligand and target expression, affinity, peptide linker length, and ligand display orientation to yield successful selection of yeast-displayed ligands against mammalian cell monolayers in an EGFR-expressing model system. A longer peptide linker allows for the robust recovery of even very weak binders and enhances recovery of strong binders on mid-expressing cell monolayers. This improvement, and quantitative characterization of other elements, empower effective yeast biopanning. Page 2328