Linked Life Data

11830593

Source:http://linkedlifedata.com/resource/pubmed/id/11830593

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
16
pubmed:dateCreated
2002-4-15
pubmed:abstractText
The horseshoe crab factor G, a heterodimeric serine protease zymogen, is activated by (1-->3)-beta-D-glucan on fungal cell walls. The activation initiates the hemolymph-clotting cascade, a critical reaction for the defense against microorganisms. In the present study, we identified the domain responsible for the glucan recognition by factor G and characterized its interaction with (1-->3)-beta-d-glucan and its derivatives. Among three domains in subunit alpha of factor G, identified as the glucan-binding domain, was the COOH-terminal xylanase Z-like domain composed of two tandem-repeating units, each of which exhibits sequence similarities to the cellulose-binding domains of bacterial xylanases. Each of the single units bound to the glucan with lower affinities, and the association constant increased two orders with the tandem-repeating structure (K(a) = 8.0 x 10(8) m(-1)). In addition to longer glucans, (1-->3)-beta-D-glucan oligosaccharides incapable of activating factor G bound also to factor G and competitively inhibited the zymogen activation. The minimum structure required for the binding was a (1-->3)-beta-d-glucan disaccharide, indicating that conformation-dependent structures are not essential for the recognition. Therefore, increasing avidity by multivalent binding sites with low affinities to simple structures on biologically active polymers may be one of the principles that allows stable and specific recognition of pathogens by pattern recognition receptors in innate immunity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
277
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
14281-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:11830593-Animals, pubmed-meshheading:11830593-Binding, Competitive, pubmed-meshheading:11830593-Binding Sites, pubmed-meshheading:11830593-Blood Coagulation Factors, pubmed-meshheading:11830593-DNA, Complementary, pubmed-meshheading:11830593-Dose-Response Relationship, Drug, pubmed-meshheading:11830593-Enzyme Activation, pubmed-meshheading:11830593-Glucans, pubmed-meshheading:11830593-Glutathione Transferase, pubmed-meshheading:11830593-Horseshoe Crabs, pubmed-meshheading:11830593-Insects, pubmed-meshheading:11830593-Kinetics, pubmed-meshheading:11830593-Models, Biological, pubmed-meshheading:11830593-Polysaccharides, pubmed-meshheading:11830593-Protein Binding, pubmed-meshheading:11830593-Protein Structure, Tertiary, pubmed-meshheading:11830593-Recombinant Fusion Proteins, pubmed-meshheading:11830593-Time Factors, pubmed-meshheading:11830593-beta-Glucans
pubmed:year
2002
pubmed:articleTitle
Duplicated binding sites for (1-->3)-beta-D-glucan in the horseshoe crab coagulation factor G: implications for a molecular basis of the pattern recognition in innate immunity.
pubmed:affiliation
Department of Molecular Biology, Graduate School of Medical Sciences, the Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka 812-8581, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't