Linked Life Data

12765339

Source:http://linkedlifedata.com/resource/pubmed/id/12765339

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2003-5-26
pubmed:abstractText
Certain mutations within the protective antigen (PA) moiety of anthrax toxin endow the protein with a dominant-negative (DN) phenotype, converting it into a potent antitoxin. Proteolytically activated PA oligomerizes to form ring-shaped heptameric complexes that insert into the membrane of an acidic intracellular compartment and promote translocation of bound edema factor and/or lethal factor to the cytosol. DN forms of PA co-oligomerize with the wild-type protein and block the translocation process. We prepared and characterized 4 DN forms: a single, a double, a triple, and a quadruple mutant. The mutants were made by site-directed mutation of the cloned form of PA in Escherichia coli and tested by various assays conducted on CHO cells or in solution. All 4 mutant PAs were competent for heptamerization and ligand binding but were defective in the pH-dependent functions: pore formation, ability to convert to the SDS-resistant heptamer, and ability to translocate bound ligand. The single mutant (F427K) showed less attenuation than the others in the pH-dependent functions and lower DN activity in a CHO cell assay. The quadruple (K397D + D425K + F427A + 2beta2-2beta3) deletion showed the most potent DN activity at low concentrations but also gave indications of low stability in a urea-mediated unfolding assay. The double mutant (K397D + D425K) and the triple (K397D + D425K + F427A) showed strong DN activity and slight reduction in stability relative to the wild-type protein. The properties of the double and the triple mutants make these forms worthy of testing in vivo as a new type of antitoxic agent for treatment of anthrax.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-10441138, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-10580119, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-11113126, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-11278644, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-11326092, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-12088665, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-1438214, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-2467303, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-3711080, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-6285339, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-7806387, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-8051159, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-9039918, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-9521715, http://linkedlifedata.com/resource/pubmed/commentcorrection/12765339-9563949
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1076-1551
pubmed:author
pubmed:issnType
Print
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
46-51
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:articleTitle
Characterization of dominant-negative forms of anthrax protective antigen.
pubmed:affiliation
Department of Microbiology and Molecular Genetics, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.