Identification of highly reactive sequences for PLP-mediated bioconjugation using a combinatorial peptide library

Area of Science:

• Chemical Biology
• Protein Engineering
• Synthetic Chemistry

Background:

• Pyridoxal 5 -phosphate (PLP)-mediated reactions enable site-specific protein functionalization.
• N-terminal protein sequences critically impact the efficiency of PLP-mediated bioconjugation.
• Optimizing protein modification requires efficient methods to screen N-terminal sequences.

Purpose of the Study:

• To develop a platform for evaluating N-terminal amino acid sequences for improved protein modification.
• To identify specific N-terminal motifs that enhance PLP-mediated bioconjugation reactions.
• To demonstrate the utility of peptide library screening in optimizing bioconjugation strategies.

Main Methods:

• Development of a generalizable combinatorial peptide library screening platform.
• Evaluation of N-terminal sequences for reactivity in PLP-mediated transamination.
• Testing of identified optimal sequences on protein substrates.

Main Results:

• An alanine-lysine N-terminal motif was identified as highly reactive in PLP-mediated transamination.
• This motif significantly increased the reactivity of peptide and protein substrates.
• The study demonstrates the first use of synthetic peptide libraries to accelerate bioconjugation discovery.

Conclusions:

• A readily encodable alanine-lysine tripeptide enhances the reliability of PLP-mediated bioconjugation.
• Combinatorial peptide library screening is an effective strategy for optimizing protein bioconjugation methods.
• This approach accelerates the discovery and application of novel protein modification techniques.