TY - JOUR
T1 - Covalent modification of the active site threonine of proteasomal β subunits and the Escherichia coli homolog HslV by a new class of inhibitors
AU - Bogyo, Matthew
AU - McMaster, John S.
AU - Gaczynska, Maria
AU - Tortorella, Domenico
AU - Goldberg, Alfred L.
AU - Ploegh, Hidde
PY - 1997/6/24
Y1 - 1997/6/24
N2 - The proteasome is a multicatalytic protease complex that plays a key role in diverse cellular functions. The peptide vinyl sulfone, carboxybenzyl-leucyl-leucyl-leucine vinyl sulfone (Z-L3VS) covalently inhibits the trypsin-like, chymotrypsin-like and, unlike lactacystin, also the peptidyl-glutamyl peptidase activity in isolated proteasomes, and blocks their function in living cells. Although described as a class of mechanism-based inhibitors for cysteine proteases, the peptide vinyl sulfone Z-L3VS and a 125I-labeled nitrophenol derivative (125I-NIP-L3VS) covalently modify the active site threonine of the catalytic β subunits of the proteasome. Modification of Thermoplasma proteasomes demonstrates the requirement for a hydroxyl amino acid (threonine, serine) as nucleophile at the β subunit's NH2 terminus. 125I-NIP-L3VS covalently modifies the HslV subunit of the Escherichia coli protease complex HslV/HslU, a reaction that requires ATP, and supports a catalytic mechanism shared with that of the eukaryotic proteasome.
AB - The proteasome is a multicatalytic protease complex that plays a key role in diverse cellular functions. The peptide vinyl sulfone, carboxybenzyl-leucyl-leucyl-leucine vinyl sulfone (Z-L3VS) covalently inhibits the trypsin-like, chymotrypsin-like and, unlike lactacystin, also the peptidyl-glutamyl peptidase activity in isolated proteasomes, and blocks their function in living cells. Although described as a class of mechanism-based inhibitors for cysteine proteases, the peptide vinyl sulfone Z-L3VS and a 125I-labeled nitrophenol derivative (125I-NIP-L3VS) covalently modify the active site threonine of the catalytic β subunits of the proteasome. Modification of Thermoplasma proteasomes demonstrates the requirement for a hydroxyl amino acid (threonine, serine) as nucleophile at the β subunit's NH2 terminus. 125I-NIP-L3VS covalently modifies the HslV subunit of the Escherichia coli protease complex HslV/HslU, a reaction that requires ATP, and supports a catalytic mechanism shared with that of the eukaryotic proteasome.
UR - http://www.scopus.com/inward/record.url?scp=0031010398&partnerID=8YFLogxK
U2 - 10.1073/pnas.94.13.6629
DO - 10.1073/pnas.94.13.6629
M3 - Article
C2 - 9192616
AN - SCOPUS:0031010398
SN - 0027-8424
VL - 94
SP - 6629
EP - 6634
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 13
ER -