Skip to main content
NCBI home page
Plant Physiology logoLink to Plant Physiology
. 1986 Mar;80(3):727–731. doi: 10.1104/pp.80.3.727

Kinetics of Ca2+/H+ Antiport in Isolated Tonoplast Vesicles from Storage Tissue of Beta vulgaris L. 1

Eduardo Blumwald 1,2, Ronald J Poole 1,2
PMCID: PMC1075191  PMID: 16664693

Abstract

Artificial pH gradients across tonoplast vesicles isolated from storage tissue of red beet (Beta vulgaris L.) were used to study the kinetics of a Ca2+/H+ antiport across this membrane. Ca2+-dependent H+ fluxes were measured by the pH-dependent fluorescence quenching of acridine orange. ΔpH-dependent Ca2+ influx was measured radiometrically. Both H+ efflux and Ca2+ influx displayed saturation kinetics and an identical dependence on external calcium with apparent Km values of 43.9 and 41.7 micromolar, respectively. Calcium influx was unaffected by an excess of Mg2+ but was inhibited by La3+ > Mn2+ > Cd2+. The apparent Km for external calcium was greatly affected (5-fold) by internal pH in the range of 6.0 to 6.5 and a transmembrane effect of internal proton binding on the affinity for external calcium is suggested.

Full text

PDF
727

Selected References

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

  1. Blumwald E., Poole R. J. Na/H Antiport in Isolated Tonoplast Vesicles from Storage Tissue of Beta vulgaris. Plant Physiol. 1985 May;78(1):163–167. doi: 10.1104/pp.78.1.163. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Blumwald E., Poole R. J. Nitrate storage and retrieval in Beta vulgaris: Effects of nitrate and chloride on proton gradients in tonoplast vesicles. Proc Natl Acad Sci U S A. 1985 Jun;82(11):3683–3687. doi: 10.1073/pnas.82.11.3683. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1016/0003-2697(76)90527-3. [DOI] [PubMed] [Google Scholar]
  4. Buckhout T. J. Characterization of Ca Transport in Purified Endoplasmic Reticulum Membrane Vesicles from Lepidium sativum L. Roots. Plant Physiol. 1984 Dec;76(4):962–967. doi: 10.1104/pp.76.4.962. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Dieter P., Marmé D. Calmodulin activation of plant microsomal Ca uptake. Proc Natl Acad Sci U S A. 1980 Dec;77(12):7311–7314. doi: 10.1073/pnas.77.12.7311. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Lee H. C., Forte J. G. A study of H+ transport in gastric microsomal vesicles using fluorescent probes. Biochim Biophys Acta. 1978 Apr 4;508(2):339–356. doi: 10.1016/0005-2736(78)90336-x. [DOI] [PubMed] [Google Scholar]
  7. Martin R. B., Richardson F. S. Lanthanides as probes for calcium in biological systems. Q Rev Biophys. 1979 May;12(2):181–209. doi: 10.1017/s0033583500002754. [DOI] [PubMed] [Google Scholar]
  8. Ohsumi Y., Anraku Y. Calcium transport driven by a proton motive force in vacuolar membrane vesicles of Saccharomyces cerevisiae. J Biol Chem. 1983 May 10;258(9):5614–5617. [PubMed] [Google Scholar]
  9. Poole R. J., Briskin D. P., Krátký Z., Johnstone R. M. Density gradient localization of plasma membrane and tonoplast from storage tissue of growing and dormant red beet : characterization of proton-transport and ATPase in tonoplast vesicles. Plant Physiol. 1984 Mar;74(3):549–556. doi: 10.1104/pp.74.3.549. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Stroobant P., Scarborough G. A. Active transport of calcium in Neurospora plasma membrane vesicles. Proc Natl Acad Sci U S A. 1979 Jul;76(7):3102–3106. doi: 10.1073/pnas.76.7.3102. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Williamson R. E., Ashley C. C. Free Ca2+ and cytoplasmic streaming in the alga Chara. Nature. 1982 Apr 15;296(5858):647–650. doi: 10.1038/296647a0. [DOI] [PubMed] [Google Scholar]

Articles from Plant Physiology are provided here courtesy of Oxford University Press

RESOURCES