Prothrombin

Prothrombin (factor II, F.II) is a vitamin K-dependent glycoprotein produced in the liver. The concentration of prothrombin in plasma is ~100ug/ml (~1.4uM). Prothrombin is a single chain molecule with a molecular weight of 72kD. Prothrombin consists of a catalytic domain followed by two kringle structures and an N-terminal domain containing 10 g-carboxy-glutamic acid (gla) residues. These gla residues allow prothrombin to bind to membranes that contain acidic phospholipids in a calcium dependent manner. The binding to membranes is required for effective presentation of prothrombin as a substrate for activation by the prothrombinase complex, which consists of activated factor X, activated cofactor V and calcium on phospholipid membrane. Activation by prothrombinase occurs by sequential cleavage after residue Arg320 then after Arg271 to produce the active protease a-thrombin (37kD) and the byproduct prothrombin fragment 1.2 (35kD). The product thrombin further cleaves prothrombin fragment 1.2 after residue Arg155 into individual prothrombin fragments 1 and 2. The activity of a-thrombin in plasma is inhibited primarily by antithrombin and the rate of inhibition is accelerated 1000-fold in the presence of optimal concentrations of heparin. Other physiological inhibitors of thrombin in the absence of heparin include a2macroglobulin and a1antitrypsin (1-3). Factor II also plays a role in maintaining vascular integrity during development and postnatal life. Mutations in Factor II leads to various forms of thrombosis and dysprothrombinemia. \n\nApplications: \nSuitable for use in ELISA. Other applications not tested.\n\nRecommended Dilution:\nOptimal dilutions to be determined by the researcher.\n\nStorage and Stability:\nMay be stored at 4 degrees C for short-term only. For long-term storage, store at -20 degrees C. Aliquots are stable for at least 12 months at -20 degrees C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.

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SPECIFICATIONS

Catalog Number

P9115-01

Size

1mg

Applications

ELISA

Reactivities

Hum

Form

Supplied as a liquid with 50% glycerol. No preservatives added.

P Type

Pab

Purity

Purified by ammonium sulfate precipitation and ion exchange chromatography.

Isotype

IgG

References

1. Mann, K.G.,: Prothrombin and Thrombin; in Hemostasis and Thrombosis, 3rd Edition, pp.184-199 (1994). Colman, R.W., Hirsh, J., Marder, V.J., Salzman, E.W., J.B. (eds), Lippincott Co., Philadelphia PA, USA. 2. Mann, K.G.: Prothrombin; Methods in Enzymology 45: 123-156 (1976). 3. Downing, M.W., Bloom, J.W., Mann, K.G.: Comparison of the Inhibition of Thrombin by Three Plasma Protease Inhibitors. Biochemistry 17: 2649-2653 (1978).

Additional Info

Recognizes human Prothrombin.