Skip to main content
Plant Physiology logoLink to Plant Physiology
. 1990 Aug;93(4):1383–1389. doi: 10.1104/pp.93.4.1383

Slow Inactivation of Ribulosebisphosphate Carboxylase during Catalysis Is Not Due to Decarbamylation of the Catalytic Site

Daryl L Edmondson 1,1, Murray R Badger 1, T John Andrews 1
PMCID: PMC1062684  PMID: 16667629

Abstract

An investigation was made of the proposal that the slow inactivation of ribulosebisphosphate carboxylase (Rubisco) activity, which occurs during in vitro assays, is due to decarbamylation of the enzyme. The level of carbamylation was compared with catalytic activity during assay conditions in which activity was both increasing and decreasing. Carbamylation level was measured using the reaction-intermediate analogue 2′ -carboxy-D-arabinitol-1, 5-bisphosphate (carboxyarabinitol-P2). A dual isotope procedure was used in which [3H]carboxyarabinitol-P2 measured total active sites and 14CO2 reported the level of carbamylation. The efficacy of the procedure was verified both in the presence and in the absence of the substrate d-ribulose-1, 5-bisphosphate (ribulose-P2). These measurements showed that changes in activity during assays were not correlated with carbamylation status. Inactivation during assays initiated with both fully and partially carbamylated enzyme was not associated with any change in carbamylation level. This implies that the loss of activity during assays is not due to ribulose-P2 binding and sequestering the E form of the enzyme. Ribulose-P2 did not appear to alter the equilibrium between carbamylated and uncarbamylated enzyme, but it did slow the rate at which enzyme was both decarbamylated and carbamylated. The most likely explanation for the loss of activity during assays appears to be the sequestration of carbamylated, Mg2+-bound active sites by an inhibitor.

Full text

PDF
1383

Selected References

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

  1. Badger M. R., Lorimer G. H. Interaction of sugar phosphates with the catalytic site of ribulose-1,5-bisphosphate carboxylase. Biochemistry. 1981 Apr 14;20(8):2219–2225. doi: 10.1021/bi00511a023. [DOI] [PubMed] [Google Scholar]
  2. Chollet R., Anderson L. L. Conformational changes associated with the reversible cold inactivation of ribulose-1,5-bisphosphate carboxylase-oxygenase. Biochim Biophys Acta. 1977 May 12;482(1):228–240. doi: 10.1016/0005-2744(77)90368-0. [DOI] [PubMed] [Google Scholar]
  3. Chollet R., Anderson L. L. Regulation of ribulose 1,5-bisphosphate carboxylase-oxygenase activities by temperature pretreatment and chloroplast metabolites. Arch Biochem Biophys. 1976 Sep;176(1):344–351. doi: 10.1016/0003-9861(76)90173-9. [DOI] [PubMed] [Google Scholar]
  4. Chu D. K., Bassham J. A. Regulation of ribulose 1,5-diphosphate carboxylase by substrates and other metabolites: further evidence for several types of binding sites. Plant Physiol. 1975 Apr;55(4):720–726. doi: 10.1104/pp.55.4.720. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Edmondson D. L., Badger M. R., Andrews T. J. A Kinetic Characterization of Slow Inactivation of Ribulosebisphosphate Carboxylase during Catalysis. Plant Physiol. 1990 Aug;93(4):1376–1382. doi: 10.1104/pp.93.4.1376. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Edmondson D. L., Badger M. R., Andrews T. J. Slow Inactivation of Ribulosebisphosphate Carboxylase during Catalysis Is Caused by Accumulation of a Slow, Tight-Binding Inhibitor at the Catalytic Site. Plant Physiol. 1990 Aug;93(4):1390–1397. doi: 10.1104/pp.93.4.1390. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Hall N. P., Pierce J., Tolbert N. E. Formation of a carboxyarabinitol bisphosphate complex with ribulose bisphosphate carboxylase/oxygenase and theoretical specific activity of the enzyme. Arch Biochem Biophys. 1981 Nov;212(1):115–119. doi: 10.1016/0003-9861(81)90349-0. [DOI] [PubMed] [Google Scholar]
  8. Jordan D. B., Chollet R. Inhibition of ribulose bisphosphate carboxylase by substrate ribulose 1,5-bisphosphate. J Biol Chem. 1983 Nov 25;258(22):13752–13758. [PubMed] [Google Scholar]
  9. Kuehn G. D., Hsu T. C. Preparative-scale enzymic synthesis of D-[14C]ribulose 1,5-bisphosphate. Biochem J. 1978 Dec 1;175(3):909–912. doi: 10.1042/bj1750909. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Laing W. A., Christeller J. T. A model for the kinetics of activation and catalysis of ribulose 1,5-bisphosphate carboxylase. Biochem J. 1976 Dec 1;159(3):563–570. doi: 10.1042/bj1590563. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Laing W. A., Christeller J. T. A steady-state kinetic study on the catalytic mechanism of ribulose bisphosphate carboxylase from soybean. Arch Biochem Biophys. 1980 Jul;202(2):592–600. doi: 10.1016/0003-9861(80)90466-x. [DOI] [PubMed] [Google Scholar]
  12. Lorimer G. H., Badger M. R., Andrews T. J. The activation of ribulose-1,5-bisphosphate carboxylase by carbon dioxide and magnesium ions. Equilibria, kinetics, a suggested mechanism, and physiological implications. Biochemistry. 1976 Feb 10;15(3):529–536. doi: 10.1021/bi00648a012. [DOI] [PubMed] [Google Scholar]
  13. McCurry S. D., Pierce J., Tolbert N. E., Orme-Johnson W. H. On the mechanism of effector-mediated activation of ribulose bisphosphate carboxylase/oxygenase. J Biol Chem. 1981 Jul 10;256(13):6623–6628. [PubMed] [Google Scholar]
  14. Miziorko H. M. Ribulose-1,5-biphosphate carboxylase. Evidence in support of the existence of distinct CO2 activator and CO2 substrate sites. J Biol Chem. 1979 Jan 25;254(2):270–272. [PubMed] [Google Scholar]
  15. Mott K. A., Berry J. A. Effects of pH on Activity and Activation of Ribulose 1,5-Bisphosphate Carboxylase at Air Level CO(2). Plant Physiol. 1986 Sep;82(1):77–82. doi: 10.1104/pp.82.1.77. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Pierce J., Tolbert N. E., Barker R. Interaction of ribulosebisphosphate carboxylase/oxygenase with transition-state analogues. Biochemistry. 1980 Mar 4;19(5):934–942. doi: 10.1021/bi00546a018. [DOI] [PubMed] [Google Scholar]
  17. Robinson S. P., Portis A. R. Ribulose-1,5-bisphosphate carboxylase/oxygenase activase protein prevents the in vitro decline in activity of ribulose-1,5-bisphosphate carboxylase/oxygenase. Plant Physiol. 1989 Jul;90(3):968–971. doi: 10.1104/pp.90.3.968. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Seemann J. R., Berry J. A., Freas S. M., Krump M. A. Regulation of ribulose bisphosphate carboxylase activity in vivo by a light-modulated inhibitor of catalysis. Proc Natl Acad Sci U S A. 1985 Dec;82(23):8024–8028. doi: 10.1073/pnas.82.23.8024. [DOI] [PMC free article] [PubMed] [Google Scholar]

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

RESOURCES