RuBisCo is an enzyme that acts both as a carboxylase and oxygenase. Why do you think RuBisCo carries out more carboxylation in C4 plants?
The enzyme RuBisCo is absent from the mesophyll cells of C4 plants. It is gift withinside the bundle-sheath cells surrounding the vascular bundles. In C4 plants, the Calvin cycle happens withinside the bundle-sheath cells. The primary CO2 acceptor withinside the mesophyll cells is phosphoenol pyruvate - a three-carbon compound. It is transformed into the four- carbon compound oxaloacetic acid (OAA). OAA is in addition transformed into malic acid. Malic acid is transported to the bundle-sheath cells, wherein it undergoes decarboxylation and CO2 fixation happens through the Calvin cycle. This prevents the enzyme RuBisCo from performing as an oxygenase.
