Abstract
The effect of bivalent cations on phosphate uptake by Saccharomyces cerevisiae was investigated. Phosphate uptake via the Na+-dependent transport system at pH 7.2 is stimulated by bivalent cations. The apparent affinity of phosphate for the transport mechanism is increased, but the apparent affinity for Na+ is decreased. Uptake of phosphate via the Na+-independent transport system is accompanied by a net proton influx of 2H+ and an efflux of 1 K+ for each phosphate ion taken up. At pH 4.5 phosphate uptake via the Na+-independent system is stimulated by bivalent cations, whereas at pH 7.2 uptake is inhibited. The effect of bivalent cations on phosphate uptake can be ascribed to a decrease in the surface potential.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Borst-Pauwels G. W., Peters P. H. Effect of the medium pH and the cell pH upon the kinetical parameters of phosphate uptake by yeast. Biochim Biophys Acta. 1977 May 2;466(3):488–495. doi: 10.1016/0005-2736(77)90341-8. [DOI] [PubMed] [Google Scholar]
- Cleland W. W. The statistical analysis of enzyme kinetic data. Adv Enzymol Relat Areas Mol Biol. 1967;29:1–32. doi: 10.1002/9780470122747.ch1. [DOI] [PubMed] [Google Scholar]
- Cockburn M., Earnshaw P., Eddy A. A. The stoicheiometry of the absorption of protons with phosphate and L-glutamate by yeasts of the genus Saccharomyces. Biochem J. 1975 Mar;146(3):705–712. doi: 10.1042/bj1460705. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GOODMAN J., ROTHSTEIN A. The active transport of phosphate into the yeast cell. J Gen Physiol. 1957 Jul 20;40(6):915–923. doi: 10.1085/jgp.40.6.915. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HOFSTEE B. H. J. On the evaluation of the constants Vm and KM in enzyme reactions. Science. 1952 Sep 26;116(3013):329–331. doi: 10.1126/science.116.3013.329. [DOI] [PubMed] [Google Scholar]
- Kobos R. K., Rechnitz G. A. Thermodynamics of AMP reactions from membrane electrode measurements of metal ion complexation. Arch Biochem Biophys. 1976 Jul;175(1):11–20. doi: 10.1016/0003-9861(76)90480-x. [DOI] [PubMed] [Google Scholar]
- Roomans G. M., Blasco F., Borst-Pauwels G. W. Cotransport of phosphate and sodium by yeast. Biochim Biophys Acta. 1977 May 16;467(1):65–71. doi: 10.1016/0005-2736(77)90242-5. [DOI] [PubMed] [Google Scholar]
- Roomans G. M., Borst-Pauwels G. W. Co-transport of anions and neutral solutes with cations across charged biological membranes. Effects of surface potential on uptake kinetics. J Theor Biol. 1978 Aug 8;73(3):453–468. doi: 10.1016/0022-5193(78)90153-4. [DOI] [PubMed] [Google Scholar]
- Roomans G. M., Borst-Pauwels G. W. Co-transport of anions and neutral solutes with cations across charged biological membranes. Effects of surface potential on uptake kinetics. J Theor Biol. 1978 Aug 8;73(3):453–468. doi: 10.1016/0022-5193(78)90153-4. [DOI] [PubMed] [Google Scholar]
- Roomans G. M., Borst-Pauwels G. W. Interaction of phosphate with monovalent cation uptake in yeast. Biochim Biophys Acta. 1977 Oct 3;470(1):84–91. doi: 10.1016/0005-2736(77)90063-3. [DOI] [PubMed] [Google Scholar]
- Seaston A., Inkson C., Eddy A. A. The absorption of protons with specific amino acids and carbohydrates by yeast. Biochem J. 1973 Aug;134(4):1031–1043. doi: 10.1042/bj1341031. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Theuvenet A. P., Borst-Pauwels G. W. Kinetics of ion translocation across charged membranes mediated by a two-site transport mechanism. Effects of polyvalent cations upon rubidium uptake into yeast cells. Biochim Biophys Acta. 1976 Apr 5;426(4):745–756. doi: 10.1016/0005-2736(76)90139-5. [DOI] [PubMed] [Google Scholar]
- Theuvenet A. P., Borst-Pauwels G. W. The influence of surface charge on the kinetics of ion-translocation across biological membranes. J Theor Biol. 1976 Apr;57(2):313–329. doi: 10.1016/0022-5193(76)90004-7. [DOI] [PubMed] [Google Scholar]