1i6p
From Proteopedia
(New page: 200px<br /><applet load="1i6p" size="450" color="white" frame="true" align="right" spinBox="true" caption="1i6p, resolution 2.00Å" /> '''CRYSTAL STRUCTURE OF...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1i6p.jpg|left|200px]]<br /><applet load="1i6p" size=" | + | [[Image:1i6p.jpg|left|200px]]<br /><applet load="1i6p" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1i6p, resolution 2.00Å" /> | caption="1i6p, resolution 2.00Å" /> | ||
'''CRYSTAL STRUCTURE OF E. COLI BETA CARBONIC ANHYDRASE (ECCA)'''<br /> | '''CRYSTAL STRUCTURE OF E. COLI BETA CARBONIC ANHYDRASE (ECCA)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Carbonic anhydrases fall into three distinct evolutionary and structural | + | Carbonic anhydrases fall into three distinct evolutionary and structural classes: alpha, beta, and gamma. The beta-class carbonic anhydrases (beta-CAs) are widely distributed among higher plants, simple eukaryotes, eubacteria, and archaea. We have determined the crystal structure of ECCA, a beta-CA from Escherichia coli, to a resolution of 2.0 A. In agreement with the structure of the beta-CA from the chloroplast of the red alga Porphyridium purpureum, the active-site zinc in ECCA is tetrahedrally coordinated by the side chains of four conserved residues. These results confirm the observation of a unique pattern of zinc ligation in at least some beta-CAS: The absence of a water molecule in the inner coordination sphere is inconsistent with known mechanisms of CA activity. ECCA activity is highly pH-dependent in the physiological range, and its expression in yeast complements an oxygen-sensitive phenotype displayed by a beta-CA-deletion strain. The structural and biochemical characterizations of ECCA presented here and the comparisons with other beta-CA structures suggest that ECCA can adopt two distinct conformations displaying widely divergent catalytic rates. |
==About this Structure== | ==About this Structure== | ||
| - | 1I6P is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with ZN as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [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] Full crystallographic information is available from [http:// | + | 1I6P is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=ZN:'>ZN</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [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] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1I6P OCA]. |
==Reference== | ==Reference== | ||
| Line 14: | Line 14: | ||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Cronk, J | + | [[Category: Cronk, J D.]] |
| - | [[Category: Cronk, M | + | [[Category: Cronk, M R.]] |
| - | [[Category: Endrizzi, J | + | [[Category: Endrizzi, J A.]] |
| - | [[Category: Neill, J | + | [[Category: Neill, J W.O.]] |
| - | [[Category: Zhang, K | + | [[Category: Zhang, K Y.J.]] |
[[Category: ZN]] | [[Category: ZN]] | ||
[[Category: carbonic anhydrase]] | [[Category: carbonic anhydrase]] | ||
| Line 27: | Line 27: | ||
[[Category: zinc coordination]] | [[Category: zinc coordination]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:08:30 2008'' |
Revision as of 11:08, 21 February 2008
|
CRYSTAL STRUCTURE OF E. COLI BETA CARBONIC ANHYDRASE (ECCA)
Overview
Carbonic anhydrases fall into three distinct evolutionary and structural classes: alpha, beta, and gamma. The beta-class carbonic anhydrases (beta-CAs) are widely distributed among higher plants, simple eukaryotes, eubacteria, and archaea. We have determined the crystal structure of ECCA, a beta-CA from Escherichia coli, to a resolution of 2.0 A. In agreement with the structure of the beta-CA from the chloroplast of the red alga Porphyridium purpureum, the active-site zinc in ECCA is tetrahedrally coordinated by the side chains of four conserved residues. These results confirm the observation of a unique pattern of zinc ligation in at least some beta-CAS: The absence of a water molecule in the inner coordination sphere is inconsistent with known mechanisms of CA activity. ECCA activity is highly pH-dependent in the physiological range, and its expression in yeast complements an oxygen-sensitive phenotype displayed by a beta-CA-deletion strain. The structural and biochemical characterizations of ECCA presented here and the comparisons with other beta-CA structures suggest that ECCA can adopt two distinct conformations displaying widely divergent catalytic rates.
About this Structure
1I6P is a Single protein structure of sequence from Escherichia coli with as ligand. Active as Carbonate dehydratase, with EC number 4.2.1.1 Full crystallographic information is available from OCA.
Reference
Crystal structure of E. coli beta-carbonic anhydrase, an enzyme with an unusual pH-dependent activity., Cronk JD, Endrizzi JA, Cronk MR, O'neill JW, Zhang KY, Protein Sci. 2001 May;10(5):911-22. PMID:11316870
Page seeded by OCA on Thu Feb 21 13:08:30 2008
