Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1998-10-2
pubmed:abstractText
The alpha C protein is a protective surface-associated antigen of group B streptococci (GBS). The prototype alpha C protein of GBS (strain A909) contains nine identical tandem repeats, each comprising 82 amino acids, flanked by N- and C-terminal domains. Clinical isolates of GBS show variable numbers of repeats with a normal distribution and a median of 9 to 10 repeats. Here, we show that escape mutants of GBS expressing one-repeat alpha C protein were 100-fold more pathogenic than GBS expressing wild-type nine-repeat alpha C protein in neonatal mice whose dams were immunized with antiserum elicited to nine-repeat alpha C protein (50% lethal doses of 1.6 x 10(3) and 1.8 x 10(5), respectively; P = 0.0073). There was no difference in pathogenicity in nonimmune mice. Enzyme-linked immunosorbent assay inhibition showed that nine-repeat but not one-repeat alpha C protein is readily available for antibody binding on the surface of intact GBS. Immune electron microscopy studies with antibodies to the capsular polysaccharide (CPS) and to the alpha C protein demonstrated localization of the nine-repeat alpha C protein and the CPS at similar distances from the cell wall. The one-repeat alpha C protein was visualized poorly and only in close proximity to the cell wall, thus suggesting that antibody binding to the protein was hindered by CPS or other cell surface components. We concluded that deletion in the repeat region of the alpha C protein enhanced the pathogenicity of GBS in immune mice by (i) loss of a protective (conformational) epitope(s) and (ii) loss of antibody binding to the alpha C protein due to a decrease in antigen size relative to cell wall components and/or CPS.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-1351681, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-1438195, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-1452329, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-1500748, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-1702759, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-1729272, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-1855984, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-2333033, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-2409199, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-2460864, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-3039291, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-3760782, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-5432063, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-6201506, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-6424501, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-6995317, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-7035367, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-7911129, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-8496678, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-8606082, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-8633028, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-8702550, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-8751902, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-8926097, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-9184008, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-9371832, http://linkedlifedata.com/resource/pubmed/commentcorrection/9712787-9393818
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0019-9567
pubmed:author
pubmed:issnType
Print
pubmed:volume
66
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4347-54
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Deletion of repeats in the alpha C protein enhances the pathogenicity of group B streptococci in immune mice.
pubmed:affiliation
Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA. gravekamp@harvard.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.