Abstract
We construct a theoretical model of the transition structure for the carboxylation reaction of ribulose-1,5-biphosphate catalyzed by Rubisco. This is a first-order saddle point on the energy hypersurface for the nucleophilic attack of carbon dioxide on CH3-(CHOH)3-CH3 at the C2 center.Ab initio analytical gradients methods at a 4-31G basis set level are used.
The carbon framework and oxygens of the stationary structure superpose with the corresponding atoms of 2-carboxyarabinitol-1,5-biphosphate, which is a transition state analog that has recently been highly refined with X-ray methods. The hydroxyl group in C3 iscis to the C2 oxygen. The C3 center is somewhat pyramidized, the dienol O2-C2-C3-O3 is not planar.
The geometry of the transition state allows for simple explanations of both the enolization of Rubisco's substrate ribulose-1,5-biphosphate, O3PO-CH2-CO-(CHOH)2-CH2-OPO3 and oxygenation reaction. The former is due to the pyramidal deformation at C3 and out of plane of O2-C2-C3-O3 framework: the enoliation is intramolecular and is probably enhanced by proton tunnelling. The latter is related with the fact that a rotation around an ethylene-like bond brings the triplet state down in energy. The reactive skeleton has a stationary geometry in the triplet state not very different from the one obtained in the global transition structure. There, the triplet is only 9 kcal/mol above the singlet. The spin densities at C2 and C3 centers clearly indicate the place where oxygenation will take place.
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References
I. Andersson, S. Knight, G. Schneider, Y. Lindqvist, T. Lundqvist, C.-I. Brändén, and G. H. Lorimer:Nature 337, 229–234 (1989).
I. Andersson, C.-I. Brändén, S. Knight, Y. Lindqvist, T. Lundqvist and G. Schneider: inProtein Structure-Function, A. Zaidi and F. Smith (Eds.), pp. 73–85, TWEL Pub., 1990.
G. Schneider, I. Andersson, C.-I. Brändén, S. Knight, Y. Lindqvist and T. Lundqvist: inEnzymatic and Model Carboxylation and Reduction Reactions for Carbon Dioxide Utilization, M. Aresta and J. V. Schloss (Eds.), pp. 367–376, Kluwer, Dordrecht, 1990.
G. Schneider and T. Lundqvist:J. Biol. Chem. 264, 7078–7083 (1989).
T. Lundqvist and G. Schneider:J. Biol. Chem. 266, 12604–12611 (1991).
T. Lundqvist and G. Schneider:Biochemistry 30, 904–908 (1991).
T. J. Andrews and G. H. Lorimer: inThe Biochemistry of Plants, vol. 10, pp. 131–218 (1987).
G. Schneider, Y. Lindqvist, and C.-I. Brändén:Ann. Rev. Biophys. Biomol. Struct. 21, 119–142 (1992).
J. W. Mc Iver,Accounts of Chemical Research 7, 72 (1974).
D. G. Truhlar, W. L. Hase, and J. T. Hynes:J. Phys. Chem. 87, 2664 (1983).
O. Tapia and J. Andrés:Chem. Phys. Lett. 109, 471–477 (1984); J. Andrés, R. Cardenas, E. Silla and O. Tapia:J. Am. Chem. Soc. 110, 666 (1988).
M. J. D. Powell:VA05 Program, Harwell Subroutine Library. Atomic Energy Research Establishment, Harwell, UK.
O. Tapia, R. Cardenas, J. Andrés, and F. Colonna-Cesari:J. Am. Chem. Soc. 110, 4046 (1988).
O. Tapia, R. Cardenas, J. Andrés, J. Krechl, M. Campillo and F. Colonna-Cesari,Int. J. Quantum Chem. 39, 767 (1991).
O. Jacob, R. Cardenas and O. Tapia:J. Am. Chem. Soc. 112, 8692 (1990).
O. Tapia, R. Cardenas and J. Andrés:Chem. Phys. Lett. (in press).
M. R. Peterson and R. A. Poirier:Program MONSTERGAUSS, University of Toronto, Ontario, Canada, 1980.
L. Pauling:Nature (London)161, 707 (1948).
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Tapia, O., Andrés, J. Towards an explanation of carboxylation/oxygenation bifunctionality in Rubisco. Transition structure for the carboxylation reaction of 2,3,4-pentanetriol. Mol Eng 2, 37–41 (1992). https://doi.org/10.1007/BF00999521
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DOI: https://doi.org/10.1007/BF00999521