Crystallisation and Preliminary X-ray Studies of Spinach Ribulose-1,5-bisphosphate Carboxylase/Oxygenase

Ribulose-1,5-bisphosphate carboxylase/oxygenase, Rubisco is bifunctional (Miziorko, Lorimer, 1983). In photosynthesis, the carboxylase activity of the enzyme catalyzes the condensation of CO2 to ribulose 1,5-bisphosphate (RuBP) to yield two moles of 3-D-phosphoglycerate (PGA). The oxygenase activity, on the other hand, catalyzes the addition of O2 to RuBP to yield PGA and 2-phosphoglycolate. The last reaction results in net loss of fixed CO2. An understanding of the structural basis for these two activities is therefore important for genetic modifications of Rubisco in plants (Sommerville, Ogren, 1982).