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Functional alpha 2-macroglobulin half-molecules induced by cadmium.

F Pochon·M Barray·E Delain
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Abstract

Human alpha 2-macroglobulin can be reversibly dissociated by Cd2+ at low ionic strength in half-molecules which retain their ability to bind tightly plasmin and chymotrypsin. The steady state kinetic parameters of these proteinases towards chromogenic substrates when bound to half-molecules are not greatly different from those determined for these enzymes linked to whole alpha 2M molecules. Cd2+ can also induce the dissociation of plasmin- and chymotrypsin - alpha 2M complexes into proteinase-alpha 2M half-molecule conjugates. These results, taken with the fact that monomeric units of alpha 2M cannot bind these proteinases, strongly suggest that each active site of alpha 2M consists in a specific arrangement of two monomeric units linked by disulfide bridges.

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Binding SitesCadmiumChymotrypsinFibrinolysinHumansKineticsalpha-MacroglobulinsJournal Article

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BibTeXRIS

F Pochon, M Barray, E Delain. 1987-12-16. Functional alpha 2-macroglobulin half-molecules induced by cadmium.. https://doi.org/10.1016/0006-291x(87)90394-9

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