1MOO

Site Specific Mutant (H64A) of Human Carbonic Anhydrase II at high resolution

Summary for 1MOO

• Entry DOI: 10.2210/pdb1moo/pdb
• Related: 1G0E 1G0F
• Descriptor: Carbonic Anhydrase II, ZINC ION, MERCURY (II) ION, ... (5 entities in total)
• Functional Keywords: high-resolution, 4-methylimidazole, twisted beta sheet, zinc metalloenzyme, lyase
• Biological source: Homo sapiens (human)
• Cellular location: Cytoplasm : P00918
• Total number of polymer chains: 1
• Total formula weight: 29652.20

Authors

Duda, D.M.,Govindasamy, L.,Agbandje-McKenna, M.,Tu, C.K.,Silverman, D.N.,McKenna, R. (deposition date: 2002-09-09, release date: 2002-09-18, Last modification date: 2024-02-14)

Primary citation

Duda, D.,Govindasamy, L.,Agbandje-McKenna, M.,Tu, C.,Silverman, D.N.,McKenna, R.
The refined atomic structure of carbonic anhydrase II at 1.05 A resolution: implications of chemical rescue of proton transfer.
Acta Crystallogr.,Sect.D, 59:93-104, 2003

PubMed Abstract: Using synchrotron radiation and a CCD detector, X-ray data have been collected at 100 K for the His64Ala mutant of human carbonic anhydrase II complexed with 4-methylimidazole (4-MI) to a maximal 1.05 A resolution, allowing full anisotropic least-squares refinement. The refined model has a conventional R factor of 15.7% for all reflections. The C(alpha) coordinates of the model presented here have an r.m.s. deviation of 0.10 A relative to the previously determined structure at 1.6 A resolution. Several amino-acid residues (six of the 255 observed) have been identified with multiple rotamer side-chain conformations. C, N and O atoms can be differentiated with selective electron-density map contouring. The estimated standard deviations for all main-chain non-H atom bond lengths and angles are 0.013 and 0.030 A, respectively, based on unrestrained full-matrix least-squares refinement. This structure gives detailed information about the tetrahedrally arranged zinc ion coordinated by three histidine N atoms (His94 N(epsilon 2), His96 N(epsilon2) and His119 N(delta1)) and a water/hydroxide, the multiple binding sites of the proton chemical rescue molecule 4-MI and the solvent networks linking the zinc-bound water/hydroxide and 4-MI molecules. This structure presents the highest resolution structure of a carbonic anhydrase isozyme so far determined and adds to the understanding of proton-transfer processes.

PubMed: 12499545
DOI: 10.1107/S0907444902019455

Experimental method

X-RAY DIFFRACTION (1.05 Å)