Fig. 1: Rapid generation of d-peptide binders leverages automated flow protein synthesis coupled with mirror-image phage display.

Automated flow protein synthesis can rapidly manufacture proteins with l- or d-amino acids. Subsequent folding and biochemical purification of each polypeptide chain affords synthetic protein pairs which are mirror images of each other. Phage display screening of the d-protein enantiomer with stapled alpha-helical peptides can reveal sequences with low-micromolar binding affinity. Mirroring of the hit peptides from l- to d-chirality affords binders to the native L-protein with similar affinity. Abbreviations: MDM2, mouse double minute 2 homolog; CHIP, C-terminus of Hsc70-interacting protein.