Murinoglobulin-1 (Mug1)

A proteinase activates the inhibitor by specific proteolysis in the bait region, which, by an unknown mechanism leads to reaction in the cysteinyl-glutamyl internal thiol ester site and to a conformational change, whereas the proteinase is trapped or covalently bound to the inhibitor. While in the tetrameric proteinase inhibitors steric inhibition is sufficiently strong, monomeric forms require a covalent linkage between the activated glutamyl residue of the initial thiol ester and a terminal amino group of a lysine or another nucleophilic group on the proteinase, for inhibition to work.

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