Reaction of antithrombin with proteases. Evidence for a specific reaction with papain.

Article Details

Citation

Valeri AM, Wilson SM, Feinman RD

Reaction of antithrombin with proteases. Evidence for a specific reaction with papain.

Biochim Biophys Acta. 1980 Aug 7;614(2):526-33.

PubMed ID
7407200 [ View in PubMed
]
Abstract

Experiments were performed to determine if the sulfhydryl protease, papain (EC 3.4.22.2), reacts with the plasma protease inhibitor antithrombin (antithrombin III, heparin cofactor) on a specific manner analogous to the reaction of thrombin (EC 3.4.21.5) and other serine proteases with this inhibitor. The esterolytic activity of papain is blocked by the addition of antithrombin, but not by antithrombin-thrombin complex or by protein substrates such as bovine serum albumin. Likewise, in the presence of papain, antithrombin was unable to displace the active site dye proflavine from thrombin, or to inhibit thrombin-catalysed hydrolysis of an anilide substrate. The reaction of antithrombin and papain was not accelerated by low concentrations of heparin. Approximately stoichiometric amounts of heparin completely inhibited the reaction of papain with antithrombin. The mutual inhibition indicates that plasma antithrombin does react with papain but the reaction differs from the interaction with coagulation factors, particularly in the heparin effect.

DrugBank Data that Cites this Article

Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
ProflavineProthrombinProteinHumans
No
Other/unknown
Details