Fig 5.

The carbonic anhydrase catalytic reaction, localization and domain structure CAs catalyse the reversible hydration of CO₂ to H⁺ and HCO₃⁻. CAIX and CAXII are cell membrane located, as demonstrated by immunofluorescence of CAIX-expressing cells, in contrast to the cytosolic distribution of CAII. Domain organization of the membrane-bound hypoxia inducible CAIX and CAXII, and the constitutive cytosolic CAII: PG = proteoglycan-like domain, CA = catalytic domain, TM = transmembrane domain, IC = intracellular C-terminal tail.