Linked Life Data

9143289

Source:http://linkedlifedata.com/resource/pubmed/id/9143289

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1997-6-5
pubmed:databankReference
pubmed:abstractText
The coronavirus, mouse hepatitis virus strain A59 (MHV), expresses a chymotrypsin-like cysteine proteinase (3CLpro) within the gene 1 polyprotein. The MHV 3CLpro is similar to the picornavirus 3C proteinases in the relative location of confirmed catalytic histidine and cysteine residues and in the predicted use of Q/(S, A, G) dipeptide cleavage sites. However, less is known concerning the participation of aspartic acid or glutamic acid residues in catalysis by the coronavirus 3C-like proteinases or of the precise coding sequence of 3CLpro within the gene 1 polyprotein. In this study, aspartic acid residues in MHV 3CLpro were mutated and the mutant proteinases were tested for activity in an in vitro trans cleavage assay. MHV 3CLpro was not inactivated by substitutions at Asp3386 (D53) or Asp3398 (D65), demonstrating that they were not catalytic residues. MHV 3CLpro was able to cleave at a glutamine-glycine (QG3607-8) dipeptide within the 3CLpro domain upstream from the predicted carboxy-terminal QS3636-6 cleavage site of 3CLpro. The predicted full-length 3CLpro (S3334 to Q3635) had an apparent mass of 27 kDa, identical to the p27 3CLpro in cells, whereas the truncated proteinase (S3334 to Q3607) had an apparent mass of 24 kDa. This 28-amino-acid carboxy-terminal truncation of 3CLpro rendered it inactive in a trans cleavage assay. Thus, MHV 3CLpro was able to cleave at a site within the putative full-length proteinase, but the entire predicted 3CLpro domain was required for activity. These studies suggest that the coronavirus 3CL-proteinases may have a substantially different structure and catalytic mechanism that other 3C-like proteinases.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0042-6822
pubmed:author
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
230
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
335-42
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Determinants of mouse hepatitis virus 3C-like proteinase activity.
pubmed:affiliation
Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2581, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.