RubisCo enzyme :
RubisCo enzyme is present in all photosynthetic organisms. It fixes atmospheric carbon dioxide to 3−Phosphoglyceric acid and is the basis for glucose synthesis.
It is present in every C3 plant, C4 plant (within bundle sheath cells), and CAM plant that carries out photosynthesis.
It is also present in photosynthetic bacteria like cyanobacteria and in dinoflagellates and unicellular photosynthetic algae that convert CO2 to organic matter.
It constitutes nearly 30–50% of the total soluble protein of chloroplasts and thus, accounts for the most abundant enzyme in the world.