Skip to main content
Protein Science : A Publication of the Protein Society logoLink to Protein Science : A Publication of the Protein Society
. 1995 Oct;4(10):2129–2137. doi: 10.1002/pro.5560041019

Thrombin-binding affinities of different disulfide-bonded isomers of the fifth EGF-like domain of thrombomodulin.

M J Hunter 1, E A Komives 1
PMCID: PMC2142985  PMID: 8535250

Abstract

The fifth EGF-like domain of thrombomodulin (TM), both with and without the amino acids that connect the fifth domain to the sixth domain, has been synthesized and refolded to form several different disulfide-bonded isomers. The domain without the connecting region formed three disulfide-bonded isomers upon refolding under redox conditions. Of these three isomers, the (1-2,3-4,5-6) bonded isomer was the best inhibitor of fibrinogen clotting and also of the thrombin-TM interaction that results in protein C activation, but all the isomers were inhibitors in both assays. The isomer containing an EGF-like disulfide-bonding pattern (1-3,2-4,5-6) was not found among the oxidation products. The domain with the connecting region amino acids (DIDE) at the C-terminus formed two isolable products upon refolding in redox buffer. These products had the same two disulfide-bonding patterns as the earliest and latest eluting isomers of the domain without the DIDE. In order to compare the thrombin-binding affinities of these isomers to the isomer with the EGF-like disulfide bonds, acetamidomethyl protection of the second and fourth cysteines was used to force the disulfide bonds into the EGF-like pattern. Thrombin-binding affinity, measured as inhibition of fibrinogen clotting and as inhibition of protein C activation correlated inversely with the number of crossed disulfide bonds. As was found for the domain without the connecting region, the isomer that was the best inhibitor of fibrinogen clotting and of protein C activation was the isomer with no crossing disulfide bonds (1-2,3-4,5-6).(ABSTRACT TRUNCATED AT 250 WORDS)

Full Text

The Full Text of this article is available as a PDF (1.6 MB).

Selected References

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

  1. Cooke R. M., Wilkinson A. J., Baron M., Pastore A., Tappin M. J., Campbell I. D., Gregory H., Sheard B. The solution structure of human epidermal growth factor. 1987 May 28-Jun 3Nature. 327(6120):339–341. doi: 10.1038/327339a0. [DOI] [PubMed] [Google Scholar]
  2. Esmon C. T. The roles of protein C and thrombomodulin in the regulation of blood coagulation. J Biol Chem. 1989 Mar 25;264(9):4743–4746. [PubMed] [Google Scholar]
  3. Esmon N. L. Thrombomodulin. Prog Hemost Thromb. 1989;9:29–55. [PubMed] [Google Scholar]
  4. Graves B. J., Crowther R. L., Chandran C., Rumberger J. M., Li S., Huang K. S., Presky D. H., Familletti P. C., Wolitzky B. A., Burns D. K. Insight into E-selectin/ligand interaction from the crystal structure and mutagenesis of the lec/EGF domains. Nature. 1994 Feb 10;367(6463):532–538. doi: 10.1038/367532a0. [DOI] [PubMed] [Google Scholar]
  5. Gray W. R. Disulfide structures of highly bridged peptides: a new strategy for analysis. Protein Sci. 1993 Oct;2(10):1732–1748. doi: 10.1002/pro.5560021017. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Harvey T. S., Wilkinson A. J., Tappin M. J., Cooke R. M., Campbell I. D. The solution structure of human transforming growth factor alpha. Eur J Biochem. 1991 Jun 15;198(3):555–562. doi: 10.1111/j.1432-1033.1991.tb16050.x. [DOI] [PubMed] [Google Scholar]
  7. Hayashi T., Zushi M., Yamamoto S., Suzuki K. Further localization of binding sites for thrombin and protein C in human thrombomodulin. J Biol Chem. 1990 Nov 25;265(33):20156–20159. [PubMed] [Google Scholar]
  8. Højrup P., Magnusson S. Disulphide bridges of bovine factor X. Biochem J. 1987 Aug 1;245(3):887–891. doi: 10.1042/bj2450887. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Kurosawa S., Galvin J. B., Esmon N. L., Esmon C. T. Proteolytic formation and properties of functional domains of thrombomodulin. J Biol Chem. 1987 Feb 15;262(5):2206–2212. [PubMed] [Google Scholar]
  10. Kurosawa S., Stearns D. J., Jackson K. W., Esmon C. T. A 10-kDa cyanogen bromide fragment from the epidermal growth factor homology domain of rabbit thrombomodulin contains the primary thrombin binding site. J Biol Chem. 1988 May 5;263(13):5993–5996. [PubMed] [Google Scholar]
  11. Makino K., Morimoto M., Nishi M., Sakamoto S., Tamura A., Inooka H., Akasaka K. Proton nuclear magnetic resonance study on the solution conformation of human epidermal growth factor. Proc Natl Acad Sci U S A. 1987 Nov;84(22):7841–7845. doi: 10.1073/pnas.84.22.7841. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Montelione G. T., Wüthrich K., Nice E. C., Burgess A. W., Scheraga H. A. Solution structure of murine epidermal growth factor: determination of the polypeptide backbone chain-fold by nuclear magnetic resonance and distance geometry. Proc Natl Acad Sci U S A. 1987 Aug;84(15):5226–5230. doi: 10.1073/pnas.84.15.5226. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Moy F. J., Li Y. C., Rauenbuehler P., Winkler M. E., Scheraga H. A., Montelione G. T. Solution structure of human type-alpha transforming growth factor determined by heteronuclear NMR spectroscopy and refined by energy minimization with restraints. Biochemistry. 1993 Jul 27;32(29):7334–7353. doi: 10.1021/bi00080a003. [DOI] [PubMed] [Google Scholar]
  14. Savage C. R., Jr, Hash J. H., Cohen S. Epidermal growth factor. Location of disulfide bonds. J Biol Chem. 1973 Nov 25;248(22):7669–7672. [PubMed] [Google Scholar]
  15. Srinivasan J., Hu S., Hrabal R., Zhu Y., Komives E. A., Ni F. Thrombin-bound structure of an EGF subdomain from human thrombomodulin determined by transferred nuclear Overhauser effects. Biochemistry. 1994 Nov 22;33(46):13553–13560. doi: 10.1021/bi00250a007. [DOI] [PubMed] [Google Scholar]
  16. Stearns D. J., Kurosawa S., Esmon C. T. Microthrombomodulin. Residues 310-486 from the epidermal growth factor precursor homology domain of thrombomodulin will accelerate protein C activation. J Biol Chem. 1989 Feb 25;264(6):3352–3356. [PubMed] [Google Scholar]
  17. Tsiang M., Lentz S. R., Sadler J. E. Functional domains of membrane-bound human thrombomodulin. EGF-like domains four to six and the serine/threonine-rich domain are required for cofactor activity. J Biol Chem. 1992 Mar 25;267(9):6164–6170. [PubMed] [Google Scholar]
  18. Ye J., Liu L. W., Esmon C. T., Johnson A. E. The fifth and sixth growth factor-like domains of thrombomodulin bind to the anion-binding exosite of thrombin and alter its specificity. J Biol Chem. 1992 Jun 5;267(16):11023–11028. [PubMed] [Google Scholar]
  19. Zushi M., Gomi K., Yamamoto S., Maruyama I., Hayashi T., Suzuki K. The last three consecutive epidermal growth factor-like structures of human thrombomodulin comprise the minimum functional domain for protein C-activating cofactor activity and anticoagulant activity. J Biol Chem. 1989 Jun 25;264(18):10351–10353. [PubMed] [Google Scholar]

Articles from Protein Science : A Publication of the Protein Society are provided here courtesy of The Protein Society

RESOURCES