ULTRASTRUCTURAL AND ANTIPROTEINASE ACTIVITY MODIFICATIONS OF HUMAN ALPHA-2-MACROGLOBULIN INDUCED BY ZINC AND OTHER DIVALENT-CATIONS
- 1 December 1986
- journal article
- research article
- Vol. 42 (2), 359-364
Abstract
Native tetrameric .alpha.2-macroglobulin molecules (.alpha.2M) can be converted into a population of dimers by incubation with various divalent cations such as Zn, Cd, Mg, Cu, Ni, Co. This dissociation is completed within 30 min at 37.degree. C. These dimers have a characteristic shape and a size of about 16 .times. 8 nm, and appear to be the half of the native .alpha.2M molecule which has a clear tetrameric structure as seen in the electron microscope. At room temperature or below, dimers obtained with 5 to 100 mM Zn2+ can reassociate in long linear polymers which display a regular chain-like arrangement and a helical periodicity. The structural characteristics of this polymer are described. The trypsin inhibitory capacity of Zn2+-treated .alpha.2M has been studied in an attempt to correlate its Zn2+-induced conformational changes with its functional modifications.This publication has 14 references indexed in Scilit:
- Electron microscopy of the conformational changes of alpha 2-macroglobulin from human plasmaThe EMBO Journal, 1985
- Cadmium binding to human α2-macroglobulinBiochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology, 1984
- The effect of zinc and other divalent cations on the structure and function of human α2-macroglobulinBiochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology, 1984
- Conformation-specific precipitation of human α2-macroglobulin by divalent zinc or calf thymus histone H3Archives of Biochemistry and Biophysics, 1984
- Characterization of functional human .alpha.2-macroglobulin half-molecules isolated by limited reduction with dithiothreitolBiochemistry, 1983
- Alpha-2-Macroglobulin-Like Protease Inhibitor from the Egg White of Cuban Crocodile (Crocodylus rhombifer)1The Journal of Biochemistry, 1983
- Computer Averaging of Single Molecules of α2-Macroglobulin and the α2-Macroglobulin/Trypsin ComplexHoppe-Seyler´s Zeitschrift Für Physiologische Chemie, 1982
- Purification of human plasma α2 macroglobulin and α1 proteinase inhibitor using zinc chelate chromatographyAnalytical Biochemistry, 1979
- The electrophoretically ‘slow’ and ‘fast’ forms of the α2-macroglobulin moleculeBiochemical Journal, 1979
- Electron microscopic studies of some proteins from normal human serumJournal of Molecular Biology, 1965