Carbonic anhydrase alpha related protein, receptor_like subfamily. Carbonic anhydrase related proteins (CARPs) are sequence similar to carbonic anhydrases. Carbonic anhydrases are zinc-containing enzymes that catalyze the reversible hydration of carbon dioxide in a two-step mechanism. CARPs have lost conserved histidines involved in zinc binding and consequently their catalytic activity. This sub-family of carbonic anhydrase-related domains found in tyrosine phosphatase receptors may play a role in cell adhesion.