Bait region involvement in the dimer-dimer interface of human alpha 2-macroglobulin and in mediating gross conformational change. Evidence from cysteine variants that form interdimer disulfides.

The Journal of Biological Chemistry
M E Bowen, P Gettins

Abstract

We have characterized four human alpha 2-macroglobulin (alpha 2M) bait region variants (G679C, M690C, V700C, and T705C) to test the hypothesis that the bait regions are involved in the interface between noncovalently associated dimers. All four variants folded correctly as judged by many normal properties. However, the presence of a cysteine resulted in disulfide formation between otherwise noncovalently associated dimers in all four variants. The extent of disulfide cross-linking varied with the location of the cysteine and gave a mixture of species that probably contained two, one, or zero interdimer disulfides in the tetramer. This was reflected in heterogeneity of conformational change upon thiol ester cleavage by methylamine, with the presence of crosslinks correlating with blockage of conformational change. The stoichiometry of trypsin inhibition was less in all cases than for wild-type alpha 2M. The M690C variant also showed evidence of some species with an intramolecular disulfide between bait regions of monomers within the same dimer. Taken together, the results are consistent with a location of the four bait regions in contact with, or in very close proximity to, one another. This suggests that they form all or part o...Continue Reading

References

Aug 1, 1979·The Biochemical Journal·A J BarrettC A Sayers
Aug 31, 1982·Biochemical and Biophysical Research Communications·L J Dangott, L W Cunningham
Jun 9, 1995·The Journal of Biological Chemistry·P G GettinsB C Crews
Oct 20, 1995·The Journal of Biological Chemistry·G R AndersenJ Nyborg
Jul 1, 1994·Protein Science : a Publication of the Protein Society·L C PedersenR E Stenkamp
May 1, 1959·Archives of Biochemistry and Biophysics·G L ELLMAN

❮ Previous
Next ❯

Citations

May 7, 2014·Proceedings of the National Academy of Sciences of the United States of America·Amy R WyattChristopher M Dobson
Jan 30, 2007·Protein Expression and Purification·Daniel Iván BarreraLuis Fernando Arbeláez
Apr 26, 2003·Molecular & Cellular Proteomics : MCP·Luca CuculloDamir Janigro
Apr 8, 2021·Cell Reports·Andrew Michael FreyLindsey Neil Shaw
Jun 18, 2021·The Journal of Biological Chemistry·Seandean Lykke HarwoodJan J Enghild

❮ Previous
Next ❯

Related Concepts

Related Feeds

ASBMB Publications

The American Society for Biochemistry and Molecular Biology (ASBMB) includes the Journal of Biological Chemistry, Molecular & Cellular Proteomics, and the Journal of Lipid Research. Discover the latest research from ASBMB here.