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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
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pubmed:dateCreated |
1994-7-28
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pubmed:abstractText |
Des(1-38) factor VIIa and des(1-44) factor VIIa were obtained by limited proteolysis. The binding of tissue factor to these factor VIIa-derivatives was assessed from its stimulation of the proteolytic activity on chromogenic oligopeptide substrates. Compared to native factor VIIa (KTF = 0.6 +/- 0.1 nM), Tissue factor binds to des(1-38) factor VIIa with a lower, but still significant affinity (KTF = 4.8 +/- 0.3 nM). The activity of des(1-44) factor VIIa was only slightly stimulated by TF (KTF approximately 200 nM). Binding of TF depends critically on the presence of Ca2+ ions. Ca2+ ions stimulated the activity of factor VIIa/TF with an apparent KCa = 0.16 +/- 0.02 mM. Factor VIIa in the absence of tissue factor was stimulated by Ca2+ with an apparent KCa = 0.05 +/- 0.01 mM, and similar KCa values were obtained for the truncated derivatives of factor VIIa. Measurements of Ca(2+)-induced changes in intrinsic protein fluorescence suggest a conformational change. The Ca2+ ion concentration at which this change occurred was higher for des(1-44) factor VIIa (apparent KCa = 0.14 mM) than for des(1-38)- and native factor VIIa (apparent KCa = 0.04 mM). The Tb3+ ion luminescence technique was used to further investigate the Ca2+ binding sites. Tb3+ ions bound with a lower affinity to des(1-44) factor VIIa than to des(1-38)-and native factor VIIa. The observed drastic decrease in affinity for tissue factor as a result of truncation of the 'hydrophobic stack' residues 39-44, suggest that this region of factor VIIa provides a structural determinant that together with other regions participates in tissue factor binding.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Amides,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Factor VIIa,
http://linkedlifedata.com/resource/pubmed/chemical/Peptide Fragments,
http://linkedlifedata.com/resource/pubmed/chemical/Terbium,
http://linkedlifedata.com/resource/pubmed/chemical/Thromboplastin,
http://linkedlifedata.com/resource/pubmed/chemical/Zinc,
http://linkedlifedata.com/resource/pubmed/chemical/des(1-38) factor VIIa
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pubmed:status |
MEDLINE
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pubmed:month |
Jun
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pubmed:issn |
0014-5793
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
20
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pubmed:volume |
347
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
73-9
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:8013666-Amides,
pubmed-meshheading:8013666-Amino Acid Sequence,
pubmed-meshheading:8013666-Calcium,
pubmed-meshheading:8013666-Factor VIIa,
pubmed-meshheading:8013666-Humans,
pubmed-meshheading:8013666-Hydrolysis,
pubmed-meshheading:8013666-Luminescence,
pubmed-meshheading:8013666-Models, Chemical,
pubmed-meshheading:8013666-Molecular Sequence Data,
pubmed-meshheading:8013666-Peptide Fragments,
pubmed-meshheading:8013666-Protein Binding,
pubmed-meshheading:8013666-Protein Conformation,
pubmed-meshheading:8013666-Terbium,
pubmed-meshheading:8013666-Thromboplastin,
pubmed-meshheading:8013666-Zinc
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pubmed:year |
1994
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pubmed:articleTitle |
Involvement of the hydrophobic stack residues 39-44 of factor VIIa in tissue factor interactions.
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pubmed:affiliation |
Biopharmaceuticals Research, Novo Nordisk A/S, Copenhagen Gentofte, Denmark.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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