Design and synthesis of substrate-based inhibitors of botulinum neurotoxin type B metalloprotease.
Botulinum toxin (BoNT) metalloproteases and related proteases are the most selective proteases known. X-ray crystal structures suggest that the native enzymes exist in catalytically incompetent forms that must be activated by substrate binding. In order to characterize the postulated substrate-induced conformational changes, we synthesized a series of transition state analog inhibitors (TSI) in which the dipeptide cleavage site has been replaced by tetrahedral intermediate analogs within the minimal substrate peptide sequence. Reduced amide, alpha-hydroxyamide, alpha-thio-amide, and hydroxyethylamine analogs of -Gln-Phe- were incorporated via solid phase peptide synthesis into 35-mer analogs of the minimal peptide substrate sequence. The synthesis, characterization, and inhibition kinetics for four series of compounds against holotoxin BoNT/B is described. The alpha-thiol amide derivatives of the 35-mer substrate were found to inhibit BONT/B in the low micromolar range.
Department of Chemistry, University of Wisconsin-Madison, 777 Highland Ave., Madison, WI 53705, USA.
Thorsten
T
Oost
Chanokporn
C
Sukonpan
Matthias
M
Brewer
Michael
M
Goodnough
William
W
Tepp
Eric A
EA
Johnson
Daniel H
DH
Rich
D000595:Amino Acid Sequence; D001905:Botulinum Toxins / Q000037:antagonists & inhibitors*; D015195:Drug Design; D045726:Metalloproteases / Q000037:antagonists & inhibitors*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011480:Protease Inhibitors / Q000138:chemical synthesis* / Q000494:pharmacology*; D013379:Substrate Specificity
D011480:Protease Inhibitors; D045726:Metalloproteases; D001905:Botulinum Toxins