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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
. 1984 Mar;81(6):1710–1714. doi: 10.1073/pnas.81.6.1710

Evidence for rotational contribution to protein-facilitated proton transport.

G Gros, D Lavalette, W Moll, H Gros, B Amand, F Pochon
PMCID: PMC344988  PMID: 6324213

Abstract

Two modes of molecular motion of carrier molecules can, in principle, lead to a facilitated transport of a substrate: translational and rotational diffusion. In the present study, which deals with the mechanism of the facilitated diffusion of H+ and O2 in solutions of earthworm hemoglobin, examples for both types of facilitation are presented. Only translational, not rotational, diffusion of earthworm hemoglobin appears to lead to a facilitated O2 flux. In contrast, substantial facilitated H+ fluxes of comparable size arise from rotational diffusion as well as from translational diffusion of this large protein. This is derived from measurements of facilitated H+ and O2 fluxes in earthworm hemoglobin solutions and determinations of the rotational and translational diffusion coefficients of earthworm hemoglobin with the help of a theoretical treatment of facilitated diffusion by rotational carrier diffusion. H+ transport by rotational protein diffusion appears to be a case where the often-postulated mechanism of facilitated transport by rotation of a carrier lends itself to experimental verification.

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Selected References

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  1. Anderson S. R., Brunori M., Weber G. Fluorescence studies of Aplysia and sperm whale apomyoglobins. Biochemistry. 1970 Nov 24;9(24):4723–4729. doi: 10.1021/bi00826a015. [DOI] [PubMed] [Google Scholar]
  2. Cherry R. J., Schneider G. A spectroscopic technique for measuring slow rotational diffusion of macromolecules. 2: Determination of rotational correlation times of proteins in solution. Biochemistry. 1976 Aug 24;15(17):3657–3661. doi: 10.1021/bi00662a002. [DOI] [PubMed] [Google Scholar]
  3. Cone R. A. Rotational diffusion of rhodopsin in the visual receptor membrane. Nat New Biol. 1972 Mar 15;236(63):39–43. doi: 10.1038/newbio236039a0. [DOI] [PubMed] [Google Scholar]
  4. Gros G. Concentration dependence of the self-diffusion of human and Lumbricus terrestris hemoglobin. Biophys J. 1978 Jun;22(3):453–468. doi: 10.1016/S0006-3495(78)85499-X. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Gros G., Moll W. Facilitated diffusion of CO2 across albumin solutions. J Gen Physiol. 1974 Sep;64(3):356–371. doi: 10.1085/jgp.64.3.356. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Gros G., Moll W., Hoppe H., Gros H. Proton transport by phosphate diffusion--a mechanism of facilitated CO2 transfer. J Gen Physiol. 1976 Jun;67(6):773–790. doi: 10.1085/jgp.67.6.773. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Gros G., Moll W. The diffusion of carbon dioxide in erythrocytes and hemoglobin solutions. Pflugers Arch. 1971;324(3):249–266. doi: 10.1007/BF00586422. [DOI] [PubMed] [Google Scholar]
  8. Lavalette D., Amand B., Pochon F. Rotational relaxation of 70S ribosomes by a depolarization method using triplet probes. Proc Natl Acad Sci U S A. 1977 Apr;74(4):1407–1411. doi: 10.1073/pnas.74.4.1407. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Lindstrom T. R., Koenig S. H., Boussios T., Bertles J. F. Intermolecular interactions of oxygenated sickle hemoglobin molecules in cells and cell-free solutions. Biophys J. 1976 Jun;16(6):679–689. doi: 10.1016/S0006-3495(76)85721-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. MOLL W. [The carrier function of hemoglobin in oxygen transport in erythrocytes]. Pflugers Arch Gesamte Physiol Menschen Tiere. 1962;275:412–419. [PubMed] [Google Scholar]
  11. Wittenberg J. B. The molecular mechanism of hemoglobin-facilitated oxygen diffusion. J Biol Chem. 1966 Jan 10;241(1):104–114. [PubMed] [Google Scholar]
  12. Wyman J. Facilitated diffusion and the possible role of myoglobin as a transport mechanism. J Biol Chem. 1966 Jan 10;241(1):115–121. [PubMed] [Google Scholar]
  13. Yguerabide J. Nanosecond fluorescence spectroscopy of macromolecules. Methods Enzymol. 1972;26:498–578. doi: 10.1016/s0076-6879(72)26026-8. [DOI] [PubMed] [Google Scholar]

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