Session: COMP Poster Session:

Therapeutic peptides have the advantages of good efficacy, safety, and tolerability as well as high selectivity and potency. Short peptides (<100 aa) can be chemically synthesized, allowing for a rapid design/synthesis/test/redesign cycle. Here we developed a novel therapeutic peptide-based approach to sequestering the excessive neurotransmitter acetylcholine (ACh), instead of targeting acetylcholinesterase or acetylcholine receptor (AChR), to treat overstimulation of AChR caused by organophosphate nerve agent intoxication. We surveyed and curated both natural and man-made ACh-binding proteins, extracted the ACh-binding pocket motifs, and de novo designed small peptides possessing pharmacological potency and high ACh-binding specificity. Utilizing molecular dynamics simulation and molecular docking we screened in silico hundreds of candidate peptides and examined the effects of N- and C-terminus tags and linkers/spacers on ACh binding. Three batches of top-ranked peptides (51 in total, 13 to 70 aa in length) were chemically synthesized and their ACh-binding affinity was determined using Plexera, a surface plasmon resonance (SPR)-based instrument. Eight of these peptides had K_d values < 10^-6 M, meeting the requirement for further in vitro screening and iterative computational modifications. This study demonstrated that a combined computational and experimental approach was rapid and effective in de novo design, screen and identification of potent peptides as drug candidates.

Manoj Shukla

US Army ERDC

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