2AX2

Production and X-ray crystallographic analysis of fully deuterated human carbonic anhydrase II

Summary for 2AX2

• Entry DOI: 10.2210/pdb2ax2/pdb
• Descriptor: Carbonic anhydrase II, ZINC ION (3 entities in total)
• Functional Keywords: perdeurated human carbonic anhydrase ii proton transfer, lyase
• Biological source: Homo sapiens (human)
• Cellular location: Cytoplasm: P00918
• Total number of polymer chains: 1
• Total formula weight: 29354.47

Authors

Budayova-Spano, M.,Fisher, S.Z.,Dauvergne, M.T.,Silverman, D.N.,Myles, D.A.A.,McKenna, R.M. (deposition date: 2005-09-02, release date: 2006-01-03, Last modification date: 2023-08-23)

Primary citation

Budayova-Spano, M.,Fisher, S.Z.,Dauvergne, M.T.,Agbandje-McKenna, M.,Silverman, D.N.,Myles, D.A.,McKenna, R.
Production and X-ray crystallographic analysis of fully deuterated human carbonic anhydrase II.
Acta Crystallogr.,Sect.F, 62:6-9, 2006

PubMed Abstract: Human carbonic anhydrase II (HCA II) is a zinc metalloenzyme that catalyzes the reversible hydration and dehydration of carbon dioxide and bicarbonate, respectively. The rate-limiting step in catalysis is the intramolecular transfer of a proton between the zinc-bound solvent (H2O/OH-) and the proton-shuttling residue His64. This distance (approximately 7.5 A) is spanned by a well defined active-site solvent network stabilized by amino-acid side chains (Tyr7, Asn62, Asn67, Thr199 and Thr200). Despite the availability of high-resolution (approximately 1.0 A) X-ray crystal structures of HCA II, there is currently no definitive information available on the positions and orientations of the H atoms of the solvent network or active-site amino acids and their ionization states. In preparation for neutron diffraction studies to elucidate this hydrogen-bonding network, perdeuterated HCA II has been expressed, purified, crystallized and its X-ray structure determined to 1.5 A resolution. The refined structure is highly isomorphous with hydrogenated HCA II, especially with regard to the active-site architecture and solvent network. This work demonstrates the suitability of these crystals for neutron macromolecular crystallography.

PubMed: 16511248
DOI: 10.1107/S1744309105038248

Experimental method

X-RAY DIFFRACTION (1.5 Å)