Role of carbonic anhydrase on the way to biological carbon capture through microalgae—A mini review

Gradual rise in levels of atmospheric carbon dioxide (CO 2 ) due to burning of fossil fuels has become a matter of environmental concern in the recent years. In this alarming situation capturing CO 2 and storing it to restrict its release to the atmosphere could be an attractive approach toward mitigation. Photosynthesis has been recognized as the most sustainable means to arrest CO 2 from the atmosphere and microalgae; a photosynthetic microorganism has been identified as the potential sequestering candidate with the highest carbon fixing capabilities. Cyanobacteria and algae have developed their own exclusive editions of photosynthetic carbon concentrating mechanisms (CCMs) to aid ribulose‐1,5‐bisphosphate carboxylase/oxygenase (RuBisCO) in efficient CO 2 capture. Carbonic anhydrase (CA), a zinc‐containing metallo‐enzyme has been observed to play a key role in the CCM by catalysing the reversible hydration of CO 2 into bicarbonate and a proton thereby helping in fixation of atmospheric CO 2 . This review gives an account of the importance of the different types of CA enzymes along with its locations, mechanism of action and the various studies on biosequestration of CO 2 through microalgae.