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DOMAIN STRUCTURE OF TAFI
The
N-linked glycosylation sites (N22, N51, N63. N86) are represented by N. The active site Zn2+
and residues (S299, G336, D344) involved in substrate binding are shown.
PURCHASING
AND PRODUCT INFORMATION
|
Catalog
Number
TAFI-01 |
Description
Thrombin Activatable Fibrinolysis Inhibitor |
Size
50
µg
|
Formulation
20
mM Hepes, 150 mM NaCl, pH 7.4
|
|
Storage
-80oC |
Purity
>95%
by SDS-PAGE |
Activity
Determination
Hippuryl-L-Arginine
hydrolysis |
Shelf
Life (properly stored)
12
months |
 |
Sample Gel
Information:
Gel:
Novex 4-12% Bis-Tris
Load:
Human TAFI, 1 µg per lane
Buffer:
MOPS
Standard:
SeeBluePlus 2; Myosin (191 kDa), Phosphorylase B (97 kDa), BSA (64
kDa), Glutamic Dehydrogenase (51 kDa), Alcohol Dehydrogenase (39 kDa),
Carbonic Anhydrase (28 kDa), Myoglobin Red (19 kDa), Lysozyme (14
kDa)
|
|
Sample
publications referencing our TAFI:
-
Davis,
D., et al., Blood. 2005 June 15; 105(12): 4561–4568. (TAFI
as standard in blot)
This
publication list is not all encompassing, and is only meant to
provide limited examples of how Haematologic Technologies'
products are used. We encourage you to search the literature
for other examples pertinent to your experimentation, and to
contact us with any technical questions. |
|
U.S.
Pricing |
Product
inquiry |
SAMPLE
DATA SHEETS |
ORDER
NOW! |
Overview
of TAFI
Thrombin Activatable Fibrinolysis Inhibitor (TAFI, Plasma pro-carboxypeptidase B, carboxypeptidase U) is a single chain glycoprotein zymogen (Mr=60,000) synthesized in the liver and circulating at a plasma concentration of 50 nM (1-4).
Thrombin ( plasmin, trypsin) cleavage of the zymogen releases a 92 amino acid N-terminal activation peptide containing 4 N-linked glycosylation sites (N22, N51, N63, N86) and the proposed
plasminogen recognition site. The rate of thrombin catalyzed activation of TAFI is increased 1250 fold by formation of a ternary complex with
thrombomodulin (5). The 309 amino acid C-terminal (Mr=35,783) catalytic domain
(TAFIa, pCPB) displays the properties of a basic carboxypeptidase, hydrolyzing lysine and arginine from the C-terminal position of polypeptides. This portion of the molecule is homologous to tissue carboxypeptidase B and contains 7 conserved cystine residues (64,77,136,151,160,165,291), the active site
Zn2+ coordination site (H67, E69, H196) and the basic C-terminal amino acid substrate binding pocket (D257, G244, S207).
TAFI is proposed to play a key role in the interaction between procoagulant, anticoagulant and fibrinolytic systems (5-9). Effective fibrinolysis results from the formation of a ternary complex between tPA, plasminogen and C-terminal lysine residues on fibrin. Plasminogen bound to fibrin is more effectively converted to
plasmin, thereby localizing the lytic activity to the area of the clot. Plasmin degradation of fibrin generates additional C-terminal lysine residues thereby amplifying the system locally. The ability of TAFI to bind specifically to plasminogen and to cleave C-terminal lysines on fibrin (and cell surfaces) results in down-regulation of fibrinolysis by reducing the number of plasminogen and tPA binding sites on fibrin. The activation of TAFI by the thrombin/thrombomodulin complex couples both the phenomenon of coagulation induced inhibition of fibrinolysis and the profibrinolytic effect of
activated protein C.
TAFI is prepared from fresh frozen human plasma by a modification of the method of Bajzar, et. al. (10), and supplied in HBS for storage at -80°C. Activity is determined measuring the rate of hydrolysis of hipuryl-L- Arg following activation with the thrombin/ thrombomodulin complex (11).
Properties of
TAFI
| Localization: |
Plasma |
| Plasma concentration: |
2.5 µg/ml |
| Mode of action: |
Basic
carboxypeptidase, cleaves C-terminal lysine and arginine residues. Inhibition of
fibrinolysis by removal of plasminogen binding sites on fibrin. |
| Molecular weight: |
60,000 |
| Extinction coefficient: |
| E |
|
= 14.9 (calculated form
cDNA) |
|
| Isoelectric point: |
5.0 |
| Structure: |
Single chain
glycoprotein. 92 a.a. N-terminal activation peptide, 309
a.a. catalytic
domain, 1 mol zinc, |
| Percent carbohydrate: |
19% |
| Post-translational modifications: |
4 N-linked glycosylation sites located at residues N22, N51, N63, and N86 of the
activation peptide |
PURCHASING
AND PRODUCT INFORMATION
|
Catalog
Number
TAFI-01 |
Description
Thrombin Activatable Fibrinolysis Inhibitor |
Size
50
µg
|
Formulation
20
mM Hepes, 150 mM NaCl, pH 7.4
|
|
Storage
-80oC |
Purity
>95%
by SDS-PAGE |
Activity
Determination
Hippuryl-L-Arginine
hydrolysis |
Shelf
Life (properly stored)
12
months |
|
U.S.
Pricing |
Product
inquiry |
SAMPLE
DATA SHEETS |
ORDER
NOW! |
References
1. Eaton, D.L., et.al., J.Biol.Chem., 266, 21833-21838 (1991).
2. Hendriks, D., et.al., BBA, 1034, 86-92 (1990).
3. Hendriks, D., et.al., J.Clin.Chem.Clin.Biochem., 27, 277 (1989).
4. Campbell, W., Okada, H., BBRC, 162, 933-939 (1989).
5. Bajzar, L. et al., J. Biol. Chem., 271, 16603-16608 (1996).
6. Redlitz, A., et.al. J.Clin.Invest., 96, 2534-2538 (1995).
7. Broze, G.J. and Higuchi, D.A., Blood, 88, 3815-3823 (1996).
8. Bajzar, L. and Nesheim, M., J.Biol.Chem., 268, 8608-8616 (1993).
9. Collen, D. and Lijnew, H.R., Blood, 78, 3114-3124 (1992).
10. Bajzar, L. et.al., J.Biol.Chem., 270, 14477-14484 (1995).
11. Folk, J.E. et al., J. Biol. Chem. 235, 2272-2282.(1960).
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