From Proteopediaproteopedia link
Carbonic anhydrase inhibitors. Interaction of the antiepileptic drug sulthiame with twelve mammalian isoforms: kinetic and X-Ray crystallographic studies
[CAH2_HUMAN] Defects in CA2 are the cause of osteopetrosis autosomal recessive type 3 (OPTB3) [MIM:259730]; also known as osteopetrosis with renal tubular acidosis, carbonic anhydrase II deficiency syndrome, Guibaud-Vainsel syndrome or marble brain disease. Osteopetrosis is a rare genetic disease characterized by abnormally dense bone, due to defective resorption of immature bone. The disorder occurs in two forms: a severe autosomal recessive form occurring in utero, infancy, or childhood, and a benign autosomal dominant form occurring in adolescence or adulthood. Autosomal recessive osteopetrosis is usually associated with normal or elevated amount of non-functional osteoclasts. OPTB3 is associated with renal tubular acidosis, cerebral calcification (marble brain disease) and in some cases with mental retardation.    
[CAH2_HUMAN] Essential for bone resorption and osteoclast differentiation (By similarity). Reversible hydration of carbon dioxide. Can hydrate cyanamide to urea. Involved in the regulation of fluid secretion into the anterior chamber of the eye. 
Publication Abstract from PubMed
Sulthiame, a clinically used antiepileptic, was investigated for its interaction with 12 catalytically active mammalian carbonic anhydrase (CA, EC 22.214.171.124) isoforms. The drug is a potent inhibitor of CA II, VII, IX, and XII (K(I)s of 6-56 nM), and a medium potency inhibitor against CA IV, VA, VB, and VI (K(I)s of 81-134 nM). The high resolution crystal structure of the hCA II-sulthiame adduct revealed a large number of favorable interactions between the drug and the enzyme which explain its strong low nanomolar affinity for this isoform and may also be exploited for the design of effective inhibitors incorporating sultam moieties.
Carbonic anhydrase inhibitors. Interaction of the antiepileptic drug sulthiame with twelve mammalian isoforms: kinetic and X-ray crystallographic studies.,Temperini C, Innocenti A, Mastrolorenzo A, Scozzafava A, Supuran CT Bioorg Med Chem Lett. 2007 Sep 1;17(17):4866-72. Epub 2007 Jun 14. PMID:17588751
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.