A Review on CO₂ Mitigation by Modified Microbial Carbonic Anhydrase Enzyme (CA)

The increase in atmospheric carbon dioxide (CO₂) levels, which are regarded as a significant greenhouse gas (GHGs), exerts a pivotal influence on global warming and climate change. In addition to the reduction of CO₂ emissions from anthropogenic activities, the active removal of CO₂ from the atmosphere is a more urgent necessity. Carbon capture and storage (CCS) represent a technically feasible but economically costly technology for the removal of CO₂ from the flue gases of coal-fired power plants. Conversely, the sequestration of CO₂ by biological methods demonstrates promise and offers the additional benefit that the biomass produced from the fixed CO₂ can then be utilized for other purposes. Nevertheless, the technology for mitigating CO₂ through biological means remains in its infancy, as the efficiency of CO₂ capture and fixation is currently insufficient to make it a viable option for industrial applications. The use of environmentally friendly technology, such as carbonic anhydrase as an enzyme to capture and utilize CO₂, has the potential to reduce CO₂ emissions and mitigate the effects of climate change and global warming. Carbonic anhydrase (CA) enzymes play an essential role in the capture of CO₂ through a rapid reaction with bicarbonate ions. This enzymatic mechanism accelerates the hydration of CO₂ in water-based solutions, converting CO₂ into bicarbonate ions and back again. CA enzymes exhibit a high turnover rate, which allows them to enhance CO₂ capture, conversion and utilization, making them a promising solution for the remediation of carbon-containing contaminants. However, little is investigated into the modification of CA to enhance CO₂ uptake. Therefore, this review aims at addressing the mitigation of CO₂ by modified microbial Carbonic anhydrase enzyme thereby filling in this gap.