Peptide Inhibitors of the α-Cobratoxin-Nicotinic Acetylcholine Receptor Interaction

J Med Chem. 2020 Nov 25;63(22):13709-13718. doi: 10.1021/acs.jmedchem.0c01202. Epub 2020 Nov 3.


Venomous snakebites cause >100 000 deaths every year, in many cases via potent depression of human neuromuscular signaling by snake α-neurotoxins. Emergency therapy still relies on antibody-based antivenom, hampered by poor access, frequent adverse reactions, and cumbersome production/purification. Combining high-throughput discovery and subsequent structure-function characterization, we present simple peptides that bind α-cobratoxin (α-Cbtx) and prevent its inhibition of nicotinic acetylcholine receptors (nAChRs) as a lead for the development of alternative antivenoms. Candidate peptides were identified by phage display and deep sequencing, and hits were characterized by electrophysiological recordings, leading to an 8-mer peptide that prevented α-Cbtx inhibition of nAChRs. We also solved the peptide:α-Cbtx cocrystal structure, revealing that the peptide, although of unique primary sequence, binds to α-Cbtx by mimicking structural features of the nAChR binding pocket. This demonstrates the potential of small peptides to neutralize lethal snake toxins in vitro, establishing a potential route to simple, synthetic, low-cost antivenoms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Binding Sites / drug effects
  • Binding Sites / physiology
  • Cobra Neurotoxin Proteins / antagonists & inhibitors*
  • Cobra Neurotoxin Proteins / chemistry
  • Cobra Neurotoxin Proteins / metabolism*
  • Crystallography, X-Ray
  • Dose-Response Relationship, Drug
  • Female
  • Peptide Fragments / chemistry
  • Peptide Fragments / metabolism*
  • Peptide Fragments / pharmacology*
  • Protein Structure, Secondary
  • Receptors, Nicotinic / chemistry
  • Receptors, Nicotinic / metabolism*
  • Xenopus laevis


  • Cobra Neurotoxin Proteins
  • Peptide Fragments
  • Receptors, Nicotinic
  • alpha-cobratoxin