Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
47
pubmed:dateCreated
2004-11-23
pubmed:abstractText
SARS (severe acute respiratory syndrome) has been one of the most severe viral infectious diseases last year and still remains as a highly risky public health problem around the world. Exploring the types of interactions responsible for structural stabilities of its component protein molecules constitutes one of the approaches to find a destabilization method for the virion particle. In this study, we performed a series of experiments to characterize the quaternary structure of the dimeric coronavirus main protease (M(pro), 3CL(pro)). By using the analytical ultracentrifuge, we demonstrated that the dimeric SARS coronavirus main protease exists as the major form in solution at protein concentration as low as 0.10 mg/mL at neutral pH. The enzyme started to dissociate at acidic and alkali pH values. Ionic strength has profound effect on the dimer stability indicating that the major force involved in the subunit association is ionic interactions. The effect of ionic strength on the protease molecule was reflected by the drastic change of electrostatic potential contour of the enzyme in the presence of NaCl. Analysis of the crystal structures indicated that the interfacial ionic interaction was attributed to the Arg-4...Glu-290 ion pair between the subunits. Detailed examination of the dimer-monomer equilibrium at different pH values reveals apparent pK(a) values of 8.0 +/- 0.2 and 5.0 +/- 0.1 for the Arg-4 and Glu-290, respectively. Mutation at these two positions reduces the association affinity between subunits, and the Glu-290 mutants had diminished enzyme activity. This information is useful in searching for substances that can intervene in the subunit association, which is attractive as a target to neutralize the virulence of SARS coronavirus.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
14958-70
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:15554703-Biophysical Phenomena, pubmed-meshheading:15554703-Biophysics, pubmed-meshheading:15554703-Buffers, pubmed-meshheading:15554703-Chromatography, Gel, pubmed-meshheading:15554703-Chromatography, High Pressure Liquid, pubmed-meshheading:15554703-Circular Dichroism, pubmed-meshheading:15554703-Crystallography, X-Ray, pubmed-meshheading:15554703-Dimerization, pubmed-meshheading:15554703-Endopeptidases, pubmed-meshheading:15554703-Escherichia coli, pubmed-meshheading:15554703-Hydrogen Bonding, pubmed-meshheading:15554703-Hydrogen-Ion Concentration, pubmed-meshheading:15554703-Hydrophobic and Hydrophilic Interactions, pubmed-meshheading:15554703-Kinetics, pubmed-meshheading:15554703-Models, Molecular, pubmed-meshheading:15554703-Mutagenesis, Site-Directed, pubmed-meshheading:15554703-Osmolar Concentration, pubmed-meshheading:15554703-Peptides, pubmed-meshheading:15554703-Plasmids, pubmed-meshheading:15554703-Protein Structure, Quaternary, pubmed-meshheading:15554703-Protein Structure, Tertiary, pubmed-meshheading:15554703-Recombinant Proteins, pubmed-meshheading:15554703-SARS Virus, pubmed-meshheading:15554703-Spectrometry, Fluorescence, pubmed-meshheading:15554703-Static Electricity
pubmed:year
2004
pubmed:articleTitle
Quaternary structure of the severe acute respiratory syndrome (SARS) coronavirus main protease.
pubmed:affiliation
Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't