Enhanced screening via a pure DNA-encoded peptide library enabled by an Fmoc modification

Area of Science:

• Biochemistry
• Medicinal Chemistry
• Drug Discovery

Background:

• Peptide therapeutics offer potent binding and metabolic safety for various applications.
• Current DNA-encoded peptide libraries (PDELs) are limited in length and purity due to precipitation-based purification methods.
• Existing methods restrict PDELs to 3-4 building blocks, hindering the exploration of diverse chemical spaces.

Purpose of the Study:

• To develop an improved purification strategy for generating longer and purer DNA-encoded peptide libraries (PDELs).
• To overcome the limitations of precipitation-based purification in PDEL construction.
• To enable the discovery of novel peptide-based therapeutics with enhanced properties.

Main Methods:

• Developed a solid-phase capture-based purification method for PDELs.
• Modified the Fmoc protecting group with an azido handle for click chemistry-based immobilization.
• Utilized selective immobilization for purification, enhancing library quality.

Main Results:

• Achieved >95% purity in the synthesis of a five-round PDEL.
• Demonstrated high efficiency in identifying high nanomolar binders against transferrin receptor protein 1.
• Successfully generated longer PDELs with increased purity compared to conventional methods.

Conclusions:

• The novel purification method provides a scalable and robust platform for generating high-quality, noncanonical peptide libraries.
• This advancement represents a significant breakthrough in peptide-based drug discovery.
• The developed platform facilitates the creation of more diverse and effective peptide therapeutics.