1ca2
From Proteopedia
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| 1ca2, resolution 2.00Å () | |||||||||
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| Activity: | Carbonate dehydratase, with EC number 4.2.1.1 | ||||||||
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| Resources: | FirstGlance, OCA, RCSB, PDBsum | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
REFINED STRUCTURE OF HUMAN CARBONIC ANHYDRASE II AT 2.0 ANGSTROMS RESOLUTION
Overview
The structure of human erythrocytic carbonic anhydrase II has been refined by constrained and restrained structure-factor least-squares refinement at 2.0 A resolution. The conventional crystallographic R value is 17.3%. Of 167 solvent molecules associated with the protein, four are buried and stabilize secondary structure elements. The zinc ion is ligated to three histidyl residues and one water molecule in a nearly tetrahedral geometry. In addition to the zinc-bound water, seven more water molecules are identified in the active site. Assuming that Glu-106 is deprotonated at pH 8.5, some of the hydrogen bond donor-acceptor relations in the active site can be assigned and are described here in detail. The O gamma 1 atom of Thr-199 donates its proton to the O epsilon 1 atom of Glu-106 and can function as a hydrogen bond acceptor only in additional hydrogen bonds.
About this Structure
1CA2 is a Single protein structure of sequence from Homo sapiens. This structure supersedes the now removed PDB entry 1cac. The following page contains interesting information on the relation of 1CA2 with [Carbonic Anhydrase]. Full crystallographic information is available from OCA.
Reference
Refined structure of human carbonic anhydrase II at 2.0 A resolution., Eriksson AE, Jones TA, Liljas A, Proteins. 1988;4(4):274-82. PMID:3151019 Page seeded by OCA on Fri May 2 12:30:56 2008
