Carbonic anhydrases are a group of enzymes that catalyze the reversible hydration of carbon dioxide (CO2) to bicarbonate (HCO3-) and protons (H+). They play a crucial role in various biological processes, including respiration, pH regulation, and the formation of bone.
There are several different types of carbonic anhydrases, including alpha (α), beta (β), and gamma (γ) carbonic anhydrases. These enzymes have different functions, structures, and distribution patterns, but they all share a common mechanism of catalyzing the hydration of CO2.
In the respiratory system, carbonic anhydrases are involved in the transport of CO2 from the tissues to the lungs, where it is exhaled. They catalyze the reaction between CO2 and water to form HCO3- and H+, which are then transported in the blood to the lungs. In the lungs, the bicarbonate ion is reconverted to CO2, which is then exhaled.
In the formation of bone, carbonic anhydrases play a role in the mineralization of bone by catalyzing the hydration of CO2 to bicarbonate, which is then used in the formation of calcium carbonate (CaCO3) crystals.
Potential for Carbon Capture
In addition to their biological functions, carbonic anhydrases have gained interest as tools for carbon capture. Given it’s extremely fast reaction rate of CO2, up to 1 million times per second and the fact that is react to reacts to CO2 under industrial flue gas conditions confirms the possibilities to use it the enzyme as a biocatalyst in carbon capture processes to improve performance.