1txx
From Proteopedia
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| - | [[Image:1txx.jpg|left|200px]] | + | [[Image:1txx.jpg|left|200px]] |
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| - | '''ACTIVE-SITE VARIANT OF E.COLI THIOREDOXIN''' | + | {{Structure |
| + | |PDB= 1txx |SIZE=350|CAPTION= <scene name='initialview01'>1txx</scene>, resolution 2.2Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=CU:COPPER (II) ION'>CU</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''ACTIVE-SITE VARIANT OF E.COLI THIOREDOXIN''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1TXX is a [ | + | 1TXX is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1TXX OCA]. |
==Reference== | ==Reference== | ||
| - | The CXXC motif: crystal structure of an active-site variant of Escherichia coli thioredoxin., Schultz LW, Chivers PT, Raines RT, Acta Crystallogr D Biol Crystallogr. 1999 Sep;55(Pt 9):1533-8. PMID:[http:// | + | The CXXC motif: crystal structure of an active-site variant of Escherichia coli thioredoxin., Schultz LW, Chivers PT, Raines RT, Acta Crystallogr D Biol Crystallogr. 1999 Sep;55(Pt 9):1533-8. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10489448 10489448] |
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: redox]] | [[Category: redox]] | ||
| - | ''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 14:24:39 2008'' |
Revision as of 12:24, 20 March 2008
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| , resolution 2.2Å | |||||||
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| Coordinates: | save as pdb, mmCIF, xml | ||||||
ACTIVE-SITE VARIANT OF E.COLI THIOREDOXIN
Overview
The 2.2 A crystalline structure of an oxidized active-site variant of Escherichia coli thioredoxin (Trx) has been solved. Trx is a 12 kDa enzyme which catalyzes the oxidation of dithiols and the reduction and isomerization of disulfides in other proteins. Its active site contains the common structural motif CXXC. Protein-disulfide isomerase (PDI), a 57 kDa homolog of Trx, contains four Trx-like domains. The three-dimensional structure of PDI is unknown. PDI-deficient Saccharomyces cerevisiae are inviable. An active-site variant of Trx which complements PDI-deficient yeast has the active-site sequence Cys32-Val33-Trp34-Cys35 (CVWC). The reduction potential of oxidized CVWC Trx (E degrees ' = -0.230 V) is altered significantly from that of the wild-type enzyme (E degrees ' = -0.270 V). However, the structure of the oxidized CVWC enzyme is almost identical to that of wild-type Trx. The addition of valine and tryptophan in the active site is likely to increase the reduction potential, largely by decreasing the pK(a) of the Cys32 thiol in the reduced enzyme. Unlike in wild-type Trx, significant protein-protein contacts occur in the crystal. Protein molecules related by a crystallographic twofold axis form a dimer in the crystal. The dimer forms as an extension of the twisted mixed beta-sheet which composes the backbone of each Trx structure.
About this Structure
1TXX is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
The CXXC motif: crystal structure of an active-site variant of Escherichia coli thioredoxin., Schultz LW, Chivers PT, Raines RT, Acta Crystallogr D Biol Crystallogr. 1999 Sep;55(Pt 9):1533-8. PMID:10489448
Page seeded by OCA on Thu Mar 20 14:24:39 2008
Categories: Escherichia coli | Single protein | Chivers, P T. | Raines, R T. | Schultz, L W. | CU | Cxxc | Oxidoreductase | Redox
