The Role of Carbonic Anhydrase in Regulating Photosynthetic CO2 Fixation in Higher Plants

Carbonic anhydrase (CA, EC4.2.1.1), which catalyzes the reversible reaction between HCO3 − and dissolved CO2, is widely distributed throughout the plant as well as animal kingdoms. It has relation to photosynthetic CO2 fixation, which can be inferred from its intracellular distribution. There have been several reports indicating that CA is mainly localized in the chloroplasts of C3 plants and in the cytoplasm of C4 plants [1,2,3], which is in accordance with the localization of Rubisco in C3 plants and PEPCase in C4 plants. So far the role of CA in higher plants has been less studied than in algae.