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. 1972 Mar;127(1):187–197. doi: 10.1042/bj1270187

Thiol reduction of human α2-macroglobulin. The subunit structure

J M Jones 1,*, J M Creeth 1, R A Kekwick 1
PMCID: PMC1178573  PMID: 5073741

Abstract

1. Human α2-macroglobulin was prepared from a fraction obtained during the large-scale separation of normal human plasma proteins for clinical use. 2. Sedimentation-equilibrium measurements indicated a molecular weight of 725000. A value of 18.1S was obtained for s020,w. 3. The dissociation that occurs in the pH range 4.5–2.5 and in the region of neutrality in urea-containing solutions is consistent with a dimeric structure of the molecule. 4. The effects of the thiol reagents mercaptoethanol, mercaptoethylamine and N-acetylcysteine were investigated over a range of experimental conditions. Distinct components having sedimentation coefficients of 15, 12 and 8.5S were identified. 5. Conditions were found under which limited reduction with thiol liberated a subunit with a molecular weight approximately one-quarter of that of the intact molecule. This subunit retains the serological specificity of the whole molecule.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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