Abstract
The kinetic and molecular properties of cyanobacterial glucose-6-phosphate dehydrogenase, partly purified from Anabaena sp. ATCC 27893, show that it undergoes relatively slow, reversible transitions between different aggregation states which differ in catalytic activity. Sucrose gradient centrifugation and polyacrylamide gel electrophoresis reveal three principal forms, with approximate molecular weights of 120 000 (M 1), 240 000 (M 2) and 345 000 (M 3). The relative catalytic activities are: M 1≪M 2<M 3. In concentrated solutions of the enzyme, the equilibrium favors the more active, oligomeric forms. Dilution in the absence of effectors shifts the equilibrium in favor of the M 1 form, with a marked diminution of catalytic activity. This transition is prevented by a substrate, glucose-6-phosphate, and also by glutamine. The other substrate, nicotinamide adenine dinucleotide phosphate (NADP+), and (in crude cell-free extracts) ribulose-1,5-diphosphate are negative effectors, which tend to maintain the enzyme in the M 1 form. The equilibrium state between different forms of the enzyme is also strongly dependent on hydrogen ion concentration. Although the optimal pH for catalytic activity is 7.4, dissociation to the hypoactive M 1 form is favored at pH values above 7; a pH of 6.5 is optimal for maintenace of the enzyme in the active state. Reduced nicotamide adenine dinucleotide phosphate (NADPH) and adenosine 5′-triphosphate (ATP), inhibit catalytic activity, but do not significantly affect the equilibrium state. The relevance of these findings to the regulation of enzyme activity in vivo is discussed.
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Abbreviations
- G6PD:
-
glucose-6-phosphate dehydrogenase
- 6PGD:
-
6-phosphogluconate dehydrogenase
- RUDP:
-
ribulose-1,5-diphosphate
- G6P:
-
glucose-6-phosphate
- 6PG:
-
6-phosphogluconate
References
Bassham, A. J.: The control of photosynthetic carbon metabolism. Science 172, 526–534 (1971)
Brown, A. T., Webster, G. C.: The influence of light on the respiration of the blue-green algae Anabaena. Amer. J. Bot. 40, 753–758 (1953)
Cheung, W. Y., Gibbs, M.: Dark and photometabolism of sugars by a blue-green alga: Tolypothrix tenuis. Plant Physiol. 41, 451–462 (1965)
Chrambach, A., Reisfeld, R. A., Wyckoff, M., Zaccari, J.: A procedure for rapid and sensitive staining of protein fractionated by polyacrylamide gel electrophoresis. Anal. Biochem. 20, 150–154 (1967)
Doolittle, W. F., Singer, R. A.: Mutational analysis of dark endogenous metabolism in the blue-green bacterium Anacystis nidulans. J. Bacteriol. 119, 677–683 (1974)
Frieden, C.: Kinetic aspects of regulation of metabolic processes. J. Biol. Chem. 245, 5788–5799 (1970)
Gabriel, O.: Analytical disc gel electrophoresis, pp. 565–577. In: Methods in enzymology (S. P. Colowick, N. O. Kapla, eds.), Vol. XXII. New York: Academic Press 1971
Gomori, G.: Preparation of buffers for use in enzyme studies, pp. 138–146. In: Methods in enzymology (S. P. Colowick, N. O. Kaplan, eds.) Vol. I. New York: Academic Press 1955
Grossman, A., McGowan, R. E.: Regulation of glucose 6-phosphate dehydrogenase in blue-green algae. Plant Physiol. 55, 658–662 (1975)
Hedrick, J. L., Smith, A. J.: Size and charge isomer separation and estimation of molecular weights of proteins by dise gel electrophoresis. Arch. Biochem. Biophys. 126, 155–164 (1968)
Ihlenfeldt, M. I. A., Gibson, J.: CO2 fixation and its regulation in Anacystic nidulans (Synechococcus). Arch. Microbiol. 102, 13–21 (1975)
Kurganov, B. I.: Regulation properties of slowly equilibrating association—dissociation enzyme systems. Symposium on Mechanism of Action and Regulation of Enzymes (T. Kelety, ed.), pp. 29–42. Amsterdam, North Holland 1975
Ledzian, K., Bassham, J. A.: Regulation of glucose 6-phosphate dehydrogenase in spinach chloroplasts by ribulose 1,5-diphosphate and NADPH/NADP+ ratios. Biochim. Biophys. Acta 396, 260–275 (1975)
Lowry, O. H., Rosebrough, N. J., Farr, A.L., Randall, R. J.: Protein measurement with the Folin phenol reagent. J. Biol. Chem. 193, 265–275 (1951)
Martin, G., Ames, B. N.: A method for determining the sedimentation behavior of enzymes: application to protein mixtures. J. Biol. Chem. 236, 1372–1379 (1961)
Pelroy, R. A., Bassham, J. A.: Photosynthetic and dark carbon metabolism in unicellular blue-green algae. Arch. Mikrobiol. 86, 25–38 (1972)
Pelroy, R. A., Kirk, M. R., Bassham, J. A.: Photosystem II regulation of macro-molecule synthesis in the blue-green alga Aphanocapsa 6714. J. Bacteriol. 128, 623–632 (1976a)
Pelroy, R. A., Levine, G. A., Bassham, J. A.: Kinetics of lighd-dark CO2 fixation and glucose assimilation by Aphanocapsa 6714. J. Bacteriol. 128, 633–643 (1976b)
Pelroy, R. A., Rippka, R., Stanier, R. Y.: Metabolism of glucose by unicellular blue-green algae. Arch. Mikrobiol. 87, 303–322 (1972)
Schnarrenberger, C., Oeser, A., Tolbert, N. F.: Two isoenzymes each of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase in spinach leaves. Arch. Biochem. Biophys. 154, 438–448 (1973)
Stanier, R. Y. Cohen-Bazire, G.: Phototrophic procaryotes: the cyanobacteria. Ann. Rev. Microbiol. 31, (1977)
Stanier, R. Y., Kunisawa, R., Mandel, M., Cohen-Bazire, G.: Purification and properties of unicellular blue-green algae (order Chroococcales). Bact. Rev. 35, 171–205 (1971)
Thompson, S. T., Cass, K. H., Stellwagen, E.: Blue dextran-sepharose: an affinity column for the dinucleotide fold in proteins. Proc. Nat. Acad. Sci. U.S.A. 72, 669–672 (1975)
Vallee, B. L., Hoch, F. L.: Zinc, a component of yeast alcohol dehydrogenase. Proc. Nat. Acad. Sci. U.S.A. 41, 327–330 (1955)
Wildner, G. F.: The regulation of glucose-6-phosphate dehydrogenase in chloroplasts. Z. Naturforsch. 30c, 756–760 (1975)
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Schaeffer, F., Stanier, R.Y. Glucose-6-phosphate dehydrogenase of Anabaena sp.. Arch. Microbiol. 116, 9–19 (1978). https://doi.org/10.1007/BF00408728
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DOI: https://doi.org/10.1007/BF00408728