Hinge peptide combinatorial libraries for inhilbitors of botulinum neurotoxins and saxitoxin: Deconvolution strategy

摘要: Combinatorial library screening offers a rapid process for identifying potential therapies to toxins. Hinge peptide libraries, which rely on conformational diversity rather than traditional molecular diversity, reduce the need huge numbers of syntheses and steps greatly expedite discovery active molecules. libraries having structures: Acetyl-X1–X2–hinge–X3–X4–NH2 (capped) X1–hinge–X2–X3 (uncapped), where X1 through X4 are near-equimolar mixtures twelve L-amino acids hinge = 4-aminobutyric acid, were screened inhibitory activity in bioassays botulinum neurotoxins A B (BoNT/A, BoNT/B) saxitoxin. The zinc protease reduced light chains BoNT/A /B was assayed by measuring cleavage synthetic substrates. Saxitoxin measured restoration viability neuroblastoma cells treated with ouabain veratridine. Deconvolution accomplished fixing one position at time beginning C-terminus. Primary subsets 4 fixed showed moderate levels inhibition BoNT/A. Secondary stronger bioassays. In each bioassays, potency when second be opposite side hinge, same respect C-terminus, suggesting that facilitates interaction chains. Inhibitors all three toxins studied discovered within subsets, although not necessarily primary subsets. These studies demonstrate (1) best strategy deconvoluting is residues alternately moiety, (2) it essential investigate secondary even inactive. present findings support concept increased flexibility imposed inclusion central residue small peptides increases opportunity chain interactions, providing distinct advantage over conventional libraries. rich source novel ligands modulation biomechanisms. uncovered this study may possess will lead effective neurotoxin poisoning.