Source:http://linkedlifedata.com/resource/pubmed/id/11901147
Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
23
|
pubmed:dateCreated |
2002-6-3
|
pubmed:abstractText |
This study presents the molecular structure of the extracellular domain of vaccinia virus envelope protein, A27L, determined by NMR and CD spectroscopy. A recombinant protein, eA27L-aa, containing this domain in which cysteines 71 and 72 were replaced with alanine, was constructed to prevent self-assembly due to intermolecular disulfide bonds between these two cysteines. The soluble eA27L-aa protein forms an oligomer resembling that of A27L on vaccinia virions. Heteronuclear correlation NMR spectroscopy was carried out on eA27L-aa in the presence or absence of urea to determine backbone resonance assignments. Chemical shift index (CSI) propensity analysis showed that eA27L-aa has two distinct structural domains, a relatively flexible 22-amino acid random coil in the N-terminal region and a fairly rigid alpha-helix structure in the remainder of the structure. Binding interaction studies using isothermal titration calorimetry suggest that a 12-amino acid lysine/arginine-rich segment in the N-terminal region is responsible for glycosaminoglycan binding. The rigid alpha-helix portion of eA27L-aa is probably involved in the intrinsic self-assembly, and CSI propensity analysis suggests that region N37-E49, with a residual alpha-helix tendency, is probably the self-assembly core. Self-assembly was ascribed to three hydrophobic leucine residues (Leu(41), Leu(45), and Leu(48)) in this segment. The folding mechanism of eA27L-aa was analyzed by CD spectroscopy, which revealed a two-step transition with a Gibbs free energy of 2.5 kcal/mol in the absence of urea. Based on these NMR and CD studies, a residue-specific molecular model of the extracellular domain of A27L is proposed. These studies on the molecular structure of eA27L-aa will help in understanding how vaccinia virus enters cells.
|
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical | |
pubmed:status |
MEDLINE
|
pubmed:month |
Jun
|
pubmed:issn |
0021-9258
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:day |
7
|
pubmed:volume |
277
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
20949-59
|
pubmed:dateRevised |
2006-11-15
|
pubmed:meshHeading |
pubmed-meshheading:11901147-Calorimetry,
pubmed-meshheading:11901147-Circular Dichroism,
pubmed-meshheading:11901147-Heparin,
pubmed-meshheading:11901147-Nuclear Magnetic Resonance, Biomolecular,
pubmed-meshheading:11901147-Protein Binding,
pubmed-meshheading:11901147-Protein Structure, Secondary,
pubmed-meshheading:11901147-Vaccinia virus,
pubmed-meshheading:11901147-Viral Proteins
|
pubmed:year |
2002
|
pubmed:articleTitle |
Structural analysis of the extracellular domain of vaccinia virus envelope protein, A27L, by NMR and CD spectroscopy.
|
pubmed:affiliation |
Institute of Biochemistry, National Yang-Ming University, Shih-pai, Taipei 11221, Taiwan.
|
pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|