Linked Life Data

18456010

Source:http://linkedlifedata.com/resource/pubmed/id/18456010

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2008-8-18
pubmed:abstractText
The complement system is an important recognition and effector mechanism of the innate immune system that upon activation leads to the elimination of foreign bodies. It can be activated through three pathways of which the lectin pathway is one. The lectin pathway relies on the binding of mannan-binding lectin (MBL) or the ficolins and the subsequent activation of the MBL-associated serine proteases (MASPs), namely, MASP1, 2 and 3 which all form complexes with both MBL and the ficolins. Major substrates have only been identified for MASP2 i.e. C4 and C2. For MASP1 only a few protein substrates which are cleaved at a low rate have been identified while none are known for MASP3. Since chromogenic substrate screenings have shown that MASP1 has thrombin-like activity, we wanted to investigate the catalytic potential of MASP1 towards two major proteins involved in the clotting process, fibrinogen and factor XIII, and compare the activity directly with that of thrombin. We found that rMASP1 and thrombin cleave factor XIII A-chain and the fibrinogen beta-chain at identical sites, but differ in cleavage of the fibrinogen alpha-chain. The thrombin turnover rate of factor XIII is approximately 650 times faster than that of rMASP1 at 37 degrees C, pH 7.4. rMASP1 cleavage of fibrinogen leads to the release of the proinflammatory peptide fibrinopeptide B. Thus rMASP1 has similar, but not identical specificity to thrombin and its catalytic activity for factor XIII and fibrinogen cleavage is much lower than that of thrombin. Nevertheless, rMASP1 can drive the formation of cross-linked fibrinogen. Since MASP1 is activated on contact of MBL or the ficolins with microorganisms, fibrinogen and factor XIII may be involved in the elimination of invading pathogens.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:volume
1784
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1294-300
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
The action of MBL-associated serine protease 1 (MASP1) on factor XIII and fibrinogen.
pubmed:affiliation
MRC Immunochemistry Unit, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, United Kingdom. anders.krarup@bioch.ox.ac.uk
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't