Climate Change and Environmental Sustainability

Carbonic anhydrase is a biocatalyst which is universally present in all prokaryotic as well as eukaryotic cells that catalyses the reversible conversion of CO₂ to bicarbonate with a turnover rate (k_cat) ranging between 10⁴ and 10⁶ s⁻¹. Because of the extremely efficient CO₂ conversion catalysed by CAs, their use is gaining considerable attention for applications wherever conversion of CO₂ or use of bicarbonate is involved. Since CAs are ubiquitous, extensive efforts are being made to survey CAs from various sources including microorganisms. This review focuses on various classes of CAs, their occurrence and possible uses in various environmental applications, in particular sequestration of CO₂ from industrial emissions for mitigating global warming. Mineralization of CO₂ is one field where the captured CO₂ is utilised to generate stable mineral carbonates. Bicarbonates produced after hydration of CO₂ can be utilised further in the production of biofuels and other value added products. CAs can also be used in the development of biosensors and in various medical applications such as in artificial lungs and in blood substitutes.