| Literature DB >> 14080818 |
J H MILSTONE, N OULIANOFF, V K MILSTONE.
Abstract
Thrombokinase has been isolated from bovine plasma by a procedure which begins with the highly purified product of a previously described method, chromatographs it on DEAE-cellulose, and then fractionates it by continuous flow electrophoresis, yielding 0.2 mg per liter of oxalated plasma. The electrophoretic fraction has shown a single boundary in the ultracentrifuge; and its esterase activity on toluenesulfonylarginine methyl ester has been about the same as that of thrombokinase previously isolated by repeated electrophoretic fractionations. Thrombokinase is a euglobulin with minimum solubility near pH 5.0. It is most stable within the pH range 7.5 to 9.5; but there is also a peak in the stability curve near pH 1.8. A few micrograms of thrombokinase per milliliter can activate prothrombin in the presence of EDTA. A few thousandths of a microgram causes rapid production of thrombin in the system: prothrombin, thrombokinase, calcium chloride, phosphatide, "accelerator." But, thrombokinase has less than 1/175 the proteolytic activity of crystallized trypsin.Entities:
Keywords: CASEIN; CATTLE; CENTRIFUGATION; CHEMISTRY; CHROMATOGRAPHY; EDTA; ELECTROPHORESIS; ESTERASES; EXPERIMENTAL LAB STUDY; HYDROGEN-ION CONCENTRATION; THROMBOPLASTIN; TRYPSIN
Mesh：
Substances：
Year: 1963 PMID： 14080818 PMCID： PMC2195336 DOI： 10.1085/jgp.47.2.315
Source DB: PubMed Journal: J Gen Physiol ISSN： 0022-1295 Impact factor: 4.086