Biological Trace Element Research

, Volume 121, Issue 3, pp 249–257 | Cite as

Effect of Mg2+ on the Structure and Function of Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase

  • Chen Liang
  • Wu Xiao
  • Huang Hao
  • Liu Xiaoqing
  • Liu Chao
  • Zheng Lei
  • Hong Fashui


Mg2+ in various concentrations was added to purified Rubisco in vitro to gain insight into the mechanism of molecular interactions between Mg2+ and Rubisco. The enzyme activity assays showed that the reaction between Rubisco and Mg2+ was two order, which means that the enhancement of Rubisco activity was accelerated by low concentration of Mg2+ and slowed by high concentration of Mg2+. The kinetics constant (K m) and V max was 1.91 μM and 1.13 μmol CO2 mg−1 protein∙min−1, respectively, at a low concentration of Mg2+, and 3.45 μM and 0.32 μmol CO2∙mg−1 protein∙min−1, respectively, at a high concentration of Mg2+. By UV absorption and fluorescence spectroscopy assays, the Mg2+ was determined to be directly bound to Rubisco; the binding site of Mg2+ to Rubisco was 0.275, the binding constants (K A) of the binding site were 6.33 × 104 and 5.5 × 104 l·mol−1. Based on the analysis of the circular dichroism (CD) spectra, it was concluded that the binding of Mg2+ did not alter the secondary structure of Rubisco, suggesting that the observed enhancement of Rubisco carboxylase activity was caused by a subtle structural change in the active site through the formation of the complex with Mg2+.


Mg2+ Rubisco Enzyme kinetics Spectral characteristic 



This work was supported by the National Natural Science Foundation of China (grant no. 30470150, 20671067) and by the Jiangsu Province Universities Natural Science Foundation (grant no. 06KJB180094).


  1. 1.
    Andrews TJ (1996) The bait in the Rubisco mousetrap. Nat Struct Biol 3:3–7PubMedCrossRefGoogle Scholar
  2. 2.
    Spreitzer RJ, Salvucci ME (2002) Rubisco: structure, regulatory interactions, and possibilities for a better enzyme. Annu Rev Plant Biol 53:449–485PubMedCrossRefGoogle Scholar
  3. 3.
    Portis AR Jr (2003) Rubisco activase—Rubisco’s catalytic chaperone. Photosynth Res 75:11–27PubMedCrossRefGoogle Scholar
  4. 4.
    Cleland WW, Andrews TJ, Gutteridge S, Hartman FC, Lorimer GH (1998) Mechanism of Rubisco: the carbamate as general base. Chem Rev 98:549–561PubMedCrossRefGoogle Scholar
  5. 5.
    Schreuder HA, Knight S, Curmi PM, Andersson I, Cascio D, Branden CI, Eisenberg D (1993) Crystal structure of activated tobacco Rubisco complexed with the reaction intermediate analogue 2-carboxyarabinitol 1,5-bisphosphate. Proc Natl Acad Sci U S A 90:9968–9972PubMedCrossRefGoogle Scholar
  6. 6.
    Duff AP, Andrews TJ, Curmi PM (2000) The transition between the open and closed states of rubisco is triggered by the inter-phosphate distance of the bound bisphosphate. J Mol Biol 298:903–916PubMedCrossRefGoogle Scholar
  7. 7.
    Hartman FC, Harpel MR (1994) Structure, function, regulation, and assembly of d-ribulose-1,5-bisphosphate carboxylase: oxygenase. Annu Rev Biochem 63:197–234PubMedCrossRefGoogle Scholar
  8. 8.
    Spreitzer RJ (1999) Questions about the complexity of chloroplast ribulose-1,5-bisphosphate carboxylase/oxygenase. Photosynth Res 60:29–42CrossRefGoogle Scholar
  9. 9.
    Tabita FR (1999) Microbial ribulose-1,5-bisphosphate carboxylase/oxygenase: a different perspective. Photosynth Res 60:1–28CrossRefGoogle Scholar
  10. 10.
    Lorimer GH, Miziorko HM (1980) Carbamate formation in the 2 amine group of a lysyl residue as the basis for the activation of ribulose-1,5-bisphosphate carboxylase by CO2 and Mg2+. Biochem 19(6):5321–5328Google Scholar
  11. 11.
    Mann CC (1999) Genetic engineers aim to soup up crop photosynthesis. Science 283:314–316PubMedCrossRefGoogle Scholar
  12. 12.
    Hudson GS, Evans JR, von Caemmerer S, Arvidsson YBC, Andrews TJ (1992) Reduction of ribulose-1,5-bisphosphate carboxylase/oxygenase content by antisense RNA reduces photosynthesis in transgenic tobacco plants. Plant Physiol 98:294–302PubMedGoogle Scholar
  13. 13.
    von Caemmerer S, Millgate A, Farquhar GD, Furbank RT (1997) Reduction of ribulose-1,5-bisphosphate carboxylase/oxygenase by antisense RNA in the C4 plant Flaveria bidentis leads to reduced assimilation rates and increased carbon isotope discrimination. Plant Physiol 113:469–477Google Scholar
  14. 14.
    Chen WJ, Gu YH, Zhao GW, Tao Y, Luo JP, Hu TD (2000) Effects of rare earth ions on activity of RuBPase in tobacco. Plant Science 152:145–151CrossRefGoogle Scholar
  15. 15.
    Chen WJ, Gu YH, Wang SB, Zhao GW (2000) Effects of lanthanum on activity of RuBPase in tobacco. J Rare Earth 18(3):258–261Google Scholar
  16. 16.
    Kangmin K, Archie R, Portis J (2006) Kinetic analysis of the slow inactivation of Rubisco during catalysis effects of temperature, O2 and Mg2+. Photosynth Res 87:195–204CrossRefGoogle Scholar
  17. 17.
    Sugiyama T, Nakayama N, Ogawa M, Akazawa T, Oda T (1968) Structure and function of chloroplast proteins: effect of ρ-chloromercuribenzoate treatment on the ribulose-1,5-bisphosphate carboxylase/oxygenase activity of spinach leaf fraction protein. Arch Biochem Biophys 125:98–106PubMedCrossRefGoogle Scholar
  18. 18.
    Bradford MM (1976) A rapid and sensitive method for the quantification of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem 72:248–254PubMedCrossRefGoogle Scholar
  19. 19.
    Lan Y, Mott KA (1991) Determination of apparent K m values for ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) activase using the spectrophotometric assay of Rubisco activity. Plant Physiol 95:604–609PubMedGoogle Scholar
  20. 20.
    Leonard RT, Nagahashi G, Thomson WW (1975) Effect of lanthanum on ion absorption in corn roots. Plant Physiol 55:542–546PubMedCrossRefGoogle Scholar
  21. 21.
    Lakowicz JR (1983) Principles of fluorescence spectroscopy. Plenum, New York (p 258)Google Scholar

Copyright information

© Humana Press Inc. 2007

Authors and Affiliations

  • Chen Liang
    • 1
  • Wu Xiao
    • 1
  • Huang Hao
    • 1
  • Liu Xiaoqing
    • 1
  • Liu Chao
    • 1
  • Zheng Lei
    • 1
  • Hong Fashui
    • 1
  1. 1.College of Life SciencesSuzhou UniversitySuzhouPeople’s Republic of China

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