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X-RAY ANALYSIS OF METAL SUBSTITUTED HUMAN CARBONIC ANHYDRASE II DERIVATIVES
[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
Metal-substituted crystals of human carbonic anhydrase II belonging to space group P2(1) with cell dimensions a = 42.7, b = 41.7, c = 73.0 A and beta = 104.6 degrees were analyzed crystallographically. The resolution limit ranged from 1.82 to 1.92 A with high completeness (86.2-90.7%). Cobalt(II)-substituted carbonic anhydrase has a tetrahedral coordination around the metal both at pH 6 and pH 7.8, similar to the native zinc enzyme. In contrast, the catalytically inactive copper(II), nickel(II) and manganese(II) derivatives showed increased coordination number around the metal ion. Whereas the copper is best described as penta-coordinated, the nickel and manganese are best described as hexa-coordinated. The results are briefly compared with spectroscopic observations and our current view on carbonic anhydrase catalysis.
X-ray analysis of metal-substituted human carbonic anhydrase II derivatives.,Hakansson K, Wehnert A, Liljas A Acta Crystallogr D Biol Crystallogr. 1994 Jan 1;50(Pt 1):93-100. PMID:15299481
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.