Chapter 14 - β-Carbonic Anhydrases: General Features and Medical Implications

Abstract

The β-carbonic anhydrases are a structurally unique class of carbonic anhydrases that is found in a diverse array of microorganisms, algae, plants, and invertebrates. These enzymes are likely associated with other enzymes that consume or produce carbon dioxide (CO2) or bicarbonate (HCO3−), and catalyze the interconversion of these species according to the chemical reaction CO2 + H2O ⇆ HCO3− + H+. Evolutionary offshoots of β-carbonic anhydrases hydrolyze the related substances carbonyl sulfide (COS) and carbon disulfide (CS2). In many microorganisms, β-carbonic anhydrases are essential for normal growth. Some β-carbonic anhydrases exhibit allostery, a property not observed in any other class of carbonic anhydrases. As a group, β-carbonic anhydrases are relatively weakly inhibited by sulfonamides and anions, classical inhibitors of most other carbonic anhydrases.