Why is the Photosynthetic CO2-fixing Enzyme, Rubisco, So Inefficient? Dissection of the Catalytic Chemistry by Computational Simulation and Experimental Testing

Fixation of CO2 by the enzyme Rubisco during photosynthesis produces organic compounds which feed all life. Despite this critical role, Rubisco catalyses its reaction sluggishly and, worse, discriminates poorly between CO2 and O2, leading to useless products. Our combined expertise equips us to analyse Rubisco's mechanism using quantum-chemical methods and then test predictions experimentally. We will capitalise on our previous successful studies of Rubisco by addressing emergent issues which are the keys to understanding catalytic efficiency and CO2/O2 selectivity: the roles of a carbamylated lysine; the way CO2 addition is rendered irreversible; and the spin inversion inherent in O2 addition.