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Updated: Oct 10, 2026

Hot Biological Catalysis: Isothermal Titration Calorimetry to Characterize Enzymatic Reactions
Published on: April 4, 2014
The effects of metal ions on esterase activities of urokinase
Abstract:
The esterase activity of highly purified human urokinase on Nalpha-acetylglycl-L-lysine methyl ester is strongly inhibited by 1 X 10(-5) to 1 X 10(-2)M Cu++, Hg++, Ni++, Co++, Fe+++, and Mn++ solutions, whereas Na+, K+, Ca++, and Mg++ are weakly effective. This inhibition is parallel with the inhibition of activation of plasminogenby urokinase. There is no simple linear relation between inhibiton and concentration. Addition of ethylenediaminetetraacetate or electrodialysis fully reactivates the inhibited enzyme. These results are discussed in relation to similar effects of ions on trypsin.
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