Skip to main content
NCBI home page
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1993 Mar 1;90(5):2025–2029. doi: 10.1073/pnas.90.5.2025

Protein dynamics in minimyoglobin: is the central core of myoglobin the conformational domain?

E E Di Iorio 1, W Yu 1, C Calonder 1, K H Winterhalter 1, G De Sanctis 1, G Falcioni 1, F Ascoli 1, B Giardina 1, M Brunori 1
PMCID: PMC46013  PMID: 8446624

Abstract

The kinetics of CO binding to the horse myoglobin fragment Mb-(32-139), the so-called "mini-Mb," were investigated by laser flash photolysis in 0.1 M phosphate buffer and in buffer with 75% (vol/vol) glycerol. The reaction displays complex time courses that can be approximated satisfactorily only with a sum of five exponentials. The features of the kinetic components and a comparison of the deoxy-minus-carbonyl difference spectra of mini-Mb and horse Mb obtained under equilibrium conditions, with the kinetic difference spectra resulting from the global analysis of the traces recorded between 400 and 450 nm, show that CO binding to mini-Mb is accompanied by large structural changes. In view of the fact that mini-Mb is an approximation of the Mb-(31-105) fragment encoded by the central exon of the Mb gene, this finding is particularly relevant. On the basis of our data and previous reports [De Sanctis, G., Falcioni, G., Giardina, B., Ascoli, F. & Brunori, M. (1988) J. Mol. Biol. 200, 725-733; De Sanctis, G., Falcioni, G., Grelloni, F., Desideri, A., Polizo, F., Giardina, B., Ascoli, F. & Brunori, M. (1992) J. Mol. Biol. 222, 637-643], we propose that the protein fragment encoded by the central exon of the Mb gene is the domain responsible for ligand-linked conformational transitions, while the two terminal fragments dampen the amplitude of the structural changes that accompany ligand binding, thus rendering the protein stable and kinetically more efficient in its physiological function.

Full text

PDF
2025

Selected References

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

  1. Ansari A., Berendzen J., Bowne S. F., Frauenfelder H., Iben I. E., Sauke T. B., Shyamsunder E., Young R. D. Protein states and proteinquakes. Proc Natl Acad Sci U S A. 1985 Aug;82(15):5000–5004. doi: 10.1073/pnas.82.15.5000. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Blanchetot A., Wilson V., Wood D., Jeffreys A. J. The seal myoglobin gene: an unusually long globin gene. Nature. 1983 Feb 24;301(5902):732–734. doi: 10.1038/301732a0. [DOI] [PubMed] [Google Scholar]
  3. Case D. A., Karplus M. Dynamics of ligand binding to heme proteins. J Mol Biol. 1979 Aug 15;132(3):343–368. doi: 10.1016/0022-2836(79)90265-1. [DOI] [PubMed] [Google Scholar]
  4. Craik C. S., Buchman S. R., Beychok S. Characterization of globin domains: heme binding to the central exon product. Proc Natl Acad Sci U S A. 1980 Mar;77(3):1384–1388. doi: 10.1073/pnas.77.3.1384. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Craik C. S., Buchman S. R., Beychok S. O2 binding properties of the product of the central exon of beta-globin gene. Nature. 1981 May 7;291(5810):87–90. doi: 10.1038/291087a0. [DOI] [PubMed] [Google Scholar]
  6. De Sanctis G., Falcioni G., Giardina B., Ascoli F., Brunori M. Mini-myoglobin. The structural significance of haem-ligand interactions. J Mol Biol. 1988 Apr 20;200(4):725–733. doi: 10.1016/0022-2836(88)90483-4. [DOI] [PubMed] [Google Scholar]
  7. De Sanctis G., Falcioni G., Giardina B., Ascoli F., Brunori M. Mini-myoglobin: preparation and reaction with oxygen and carbon monoxide. J Mol Biol. 1986 Mar 5;188(1):73–76. doi: 10.1016/0022-2836(86)90481-x. [DOI] [PubMed] [Google Scholar]
  8. De Sanctis G., Falcioni G., Grelloni F., Desideri A., Polizio F., Giardina B., Ascoli F., Brunori M. Mini-myoglobin. Electron paramagnetic resonance and reversible oxygenation of the cobalt derivative. J Mol Biol. 1991 Dec 5;222(3):637–643. doi: 10.1016/0022-2836(91)90501-v. [DOI] [PubMed] [Google Scholar]
  9. Di Iorio E. E., Hiltpold U. R., Filipovic D., Winterhalter K. H., Gratton E., Vitrano E., Cupane A., Leone M., Cordone L. Protein dynamics. Comparative investigation on heme-proteins with different physiological roles. Biophys J. 1991 Mar;59(3):742–754. doi: 10.1016/S0006-3495(91)82287-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Eaton W. A. The relationship between coding sequences and function in haemoglobin. Nature. 1980 Mar 13;284(5752):183–185. doi: 10.1038/284183a0. [DOI] [PubMed] [Google Scholar]
  11. FANELLI A. R., ANTONINI E., CAPUTO A. Studies on the structure of hemoglobin. I. Physicochemical properties of human globin. Biochim Biophys Acta. 1958 Dec;30(3):608–615. doi: 10.1016/0006-3002(58)90108-2. [DOI] [PubMed] [Google Scholar]
  12. Lewin R. Myoglobin gene is a big surprise. The first analysis of a myoglobin gene reveals some striking similarities and some unexpected differences from hemoglobin genes. Science. 1983 Mar 18;219(4590):1312–1312. doi: 10.1126/science.6828858. [DOI] [PubMed] [Google Scholar]
  13. Parker M. W., Tucker A. D., Tsernoglou D., Pattus F. Insights into membrane insertion based on studies of colicins. Trends Biochem Sci. 1990 Apr;15(4):126–129. doi: 10.1016/0968-0004(90)90205-p. [DOI] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES