The herpesvirus protease: mechanistic studies and discovery of inhibitors of the human cytomegalovirus protease.
The herpesvirus protease is a recently identified enzyme which is essential for viral replication. It is found in all herpesviruses and offers a new molecular target for therapeutic intervention. Its genomic structure has recently been described and consists of a large open reading frame which encodes a fusion protein containing an amino-terminal protease domain in-frame with a carboxyl-terminal "assembly protein-like" domain. Auto-processing releases the amino-terminal protease as a maturational enzyme. The herpesvirus protease has been characterized as a novel serine protease. Four surface accessible sulfhydryl groups have been identified in the human cytomegalovirus (HCMV) protease. Utilizing a fluorogenic DABCYL-EDANS substrate assay, directed screening has identified a class of sulfhydryl-modifying benzimidazolylmethyl sulfoxides which inhibits recombinant HCMV protease. Site-directed mutagenesis studies suggest oxidative modification of surface-accessible HCMV protease Cys138 (and possibly Cys161) by this class of inhibitors. The benzimidazolylmethyl sulfoxide 1 inhibits HCMV protease (IC50 = 1.9 microM), exhibits selectivity vs. mammalian serine proteases, and exhibits antiviral activity in an HCMV infected cell culture assay.
Flynn
D L
DL
Searle Research and Development, Discovery Medicinal Chemistry, St. Louis, MO 63167, USA. DLFLYN@Monsanto.com
Becker
D P
DP
Dilworth
V M
VM
Highkin
M K
MK
Hippenmeyer
P J
PJ
Houseman
K A
KA
Levine
L M
LM
Li
M
M
Moormann
A E
AE
Rankin
A
A
Toth
M V
MV
Villamil
C I
CI
Wittwer
A J
AJ
Holwerda
B C
BC
D000998:Antiviral Agents / Q000737:chemistry / Q000494:pharmacology; D003587:Cytomegalovirus / Q000187:drug effects / Q000201:enzymology; D010450:Endopeptidases / Q000187:drug effects* / Q000235:genetics; D006564:Herpesviridae / Q000187:drug effects* / Q000201:enzymology*; D006801:Humans; D011480:Protease Inhibitors / Q000737:chemistry / Q000494:pharmacology; D012697:Serine Endopeptidases / Q000187:drug effects / Q000235:genetics
D000998:Antiviral Agents; D011480:Protease Inhibitors; D010450:Endopeptidases; D012697:Serine Endopeptidases