Acetylcholine receptor-alpha-bungarotoxin interactions: determination of the region-to-region contacts by peptide-peptide interactions and molecular modeling of the receptor cavity.

摘要: Abstract In previous studies from this laboratory, the binding regions of alpha-neurotoxins on human and Torpedo acetylcholine (AcCho) receptors (AcChoRs) for receptor toxin were characterized with synthetic peptides respective molecules. In present work, representing active one molecule are each allowed to bind active-region other molecule. Thus, interaction three alpha-bungarotoxin (alpha-BTX) loop four toxin-binding AcChoR permitted determination region-region interactions between alpha-BTX receptor. Based known three-dimensional structure toxin, then assembled their appropriate toxin-contact by computer model building energy minimization. This construction cavity AcChoR. The appears be conical, 30.5 A in depth, involving several that make contact regions. One region (within residues 125-136) involved also resides a AcCho-binding site, thus demonstrating dimensions critical site both AcCho activation blocking. validity approach was first established corresponding beta chain hemoglobin alpha chain. studying two protein molecules may provide an molecular recognition which can described if is known.