5ca2
From Proteopedia
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| - | [[Image:5ca2.gif|left|200px]] | + | [[Image:5ca2.gif|left|200px]] |
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| - | '''CONFORMATIONAL MOBILITY OF HIS-64 IN THE THR-200 (RIGHT ARROW) SER MUTANT OF HUMAN CARBONIC ANHYDRASE II''' | + | {{Structure |
| + | |PDB= 5ca2 |SIZE=350|CAPTION= <scene name='initialview01'>5ca2</scene>, resolution 2.1Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene> and <scene name='pdbligand=HG:MERCURY (II) ION'>HG</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Carbonate_dehydratase Carbonate dehydratase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.1 4.2.1.1] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''CONFORMATIONAL MOBILITY OF HIS-64 IN THE THR-200 (RIGHT ARROW) SER MUTANT OF HUMAN CARBONIC ANHYDRASE II''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 5CA2 is a [ | + | 5CA2 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5CA2 OCA]. |
==Reference== | ==Reference== | ||
| - | Conformational mobility of His-64 in the Thr-200----Ser mutant of human carbonic anhydrase II., Krebs JF, Fierke CA, Alexander RS, Christianson DW, Biochemistry. 1991 Sep 24;30(38):9153-60. PMID:[http:// | + | Conformational mobility of His-64 in the Thr-200----Ser mutant of human carbonic anhydrase II., Krebs JF, Fierke CA, Alexander RS, Christianson DW, Biochemistry. 1991 Sep 24;30(38):9153-60. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1909891 1909891] |
[[Category: Carbonate dehydratase]] | [[Category: Carbonate dehydratase]] | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
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[[Category: lyase(oxo-acid)]] | [[Category: lyase(oxo-acid)]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 19:11:41 2008'' |
Revision as of 17:11, 20 March 2008
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| , resolution 2.1Å | |||||||
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| Ligands: | and | ||||||
| Activity: | Carbonate dehydratase, with EC number 4.2.1.1 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CONFORMATIONAL MOBILITY OF HIS-64 IN THE THR-200 (RIGHT ARROW) SER MUTANT OF HUMAN CARBONIC ANHYDRASE II
Contents |
Overview
The three-dimensional structure of the Thr-200----Ser (T200S) mutant of human carbonic anhydrase II (CAII) has been determined by X-ray crystallographic methods at 2.1-A resolution. This particular mutant of CAII exhibits CO2 hydrase activity that is comparable to that of the wild-type enzyme with a 2-fold stabilization of the E.HCO3- complex and esterase activity that is 4-fold greater than that of the wild-type enzyme. The structure of the mutant enzyme reveals no significant local changes accompanying the conservative T200S substitution, but an important nonlocal structural change is evident: the side chain of catalytic residue His-64 rotates away from the active site by 105 degrees about chi 1 and apparently displaces a water molecule. The displaced water molecule is present in the wild-type enzyme; however, the electron density into which this water is built is interpretable as an alternate conformation of His-64 with 10-20% occupancy. The rate constants for proton transfer from the zinc-water ligand to His-64 and from His-64 to bulk solvent are maintained in the T200S variant; therefore, if His-64 is conformationally mobile about chi 1 and/or chi 2 during catalysis, compensatory changes in solvent configuration must sustain efficient proton transfer.
Disease
Known disease associated with this structure: Osteopetrosis, autosomal recessive 3, with renal tubular acidosis OMIM:[611492]
About this Structure
5CA2 is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Conformational mobility of His-64 in the Thr-200----Ser mutant of human carbonic anhydrase II., Krebs JF, Fierke CA, Alexander RS, Christianson DW, Biochemistry. 1991 Sep 24;30(38):9153-60. PMID:1909891
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