Linked Life Data

14978117

Source:http://linkedlifedata.com/resource/pubmed/id/14978117

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2004-2-23
pubmed:abstractText
Complement evasion by different mechanisms is important for microbial virulence and survival in the host. One strategy used by pathogenic bacteria is to bind the soluble complement inhibitor factor H (fH) to their surfaces. In group B streptococci and pneumococci, fH binding has been shown to be mediated by the surface proteins beta and Hic, respectively. We showed previously that Hic binds to the middle region of fH and protects the pneumococcus from opsonophagocytosis. As the beta protein and Hic are structurally closely related, we wanted to compare the fH binding characteristics of these two proteins. By using direct binding assays with radiolabeled proteins and surface plasmon resonance analysis we show that both beta and Hic bind to the short consensus repeats 8-11 and 12-14 in the middle region of fH. Peptide mapping analysis suggested that the fH-binding sites on beta and Hic were composed of discontinuous and partially homologous sequences. Thus, the bacterial virulence proteins use multiple binding sites on fH to secure high avidity. Also, the functionally active sites on fH are thereby left free to inhibit C3b deposition and opsonophagocytosis. These results reveal the evolutionary conservation of an analogous immune evasion strategy in different types of pathogenic streptococci. Importantly, the respective virulence factors could be exploited in the development of protein-based vaccines against these pathogens.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
172
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3111-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:14978117-Amino Acid Sequence, pubmed-meshheading:14978117-Antigens, Surface, pubmed-meshheading:14978117-Bacterial Proteins, pubmed-meshheading:14978117-Binding, Competitive, pubmed-meshheading:14978117-Binding Sites, pubmed-meshheading:14978117-Carrier Proteins, pubmed-meshheading:14978117-Complement Factor H, pubmed-meshheading:14978117-DNA-Binding Proteins, pubmed-meshheading:14978117-Heparin, pubmed-meshheading:14978117-Humans, pubmed-meshheading:14978117-Molecular Sequence Data, pubmed-meshheading:14978117-Mutation, pubmed-meshheading:14978117-Peptide Mapping, pubmed-meshheading:14978117-Protein Binding, pubmed-meshheading:14978117-Sequence Homology, Amino Acid, pubmed-meshheading:14978117-Streptococcus agalactiae, pubmed-meshheading:14978117-Streptococcus pneumoniae, pubmed-meshheading:14978117-Surface Plasmon Resonance
pubmed:year
2004
pubmed:articleTitle
The group B streptococcal beta and pneumococcal Hic proteins are structurally related immune evasion molecules that bind the complement inhibitor factor H in an analogous fashion.
pubmed:affiliation
Haartman Institute, Department of Bacteriology and Immunology, University of Helsinki, Finland.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't