2dgm
From Proteopedia
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| - | [[Image:2dgm.gif|left|200px]] | + | [[Image:2dgm.gif|left|200px]] |
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| - | '''Crystal structure of Escherichia coli GadB in complex with iodide''' | + | {{Structure |
| + | |PDB= 2dgm |SIZE=350|CAPTION= <scene name='initialview01'>2dgm</scene>, resolution 1.95Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=IOD:IODIDE+ION'>IOD</scene>, <scene name='pdbligand=PLP:PYRIDOXAL-5'-PHOSPHATE'>PLP</scene>, <scene name='pdbligand=FMT:FORMIC+ACID'>FMT</scene>, <scene name='pdbligand=ACY:ACETIC+ACID'>ACY</scene> and <scene name='pdbligand=PEG:DI(HYDROXYETHYL)ETHER'>PEG</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Glutamate_decarboxylase Glutamate decarboxylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.1.15 4.1.1.15] | ||
| + | |GENE= gadB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | ||
| + | }} | ||
| + | |||
| + | '''Crystal structure of Escherichia coli GadB in complex with iodide''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 2DGM is a [ | + | 2DGM 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=2DGM OCA]. |
==Reference== | ==Reference== | ||
| - | Escherichia coli acid resistance: pH-sensing, activation by chloride and autoinhibition in GadB., Gut H, Pennacchietti E, John RA, Bossa F, Capitani G, De Biase D, Grutter MG, EMBO J. 2006 Jun 7;25(11):2643-51. Epub 2006 May 4. PMID:[http:// | + | Escherichia coli acid resistance: pH-sensing, activation by chloride and autoinhibition in GadB., Gut H, Pennacchietti E, John RA, Bossa F, Capitani G, De Biase D, Grutter MG, EMBO J. 2006 Jun 7;25(11):2643-51. Epub 2006 May 4. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/16675957 16675957] |
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Glutamate decarboxylase]] | [[Category: Glutamate decarboxylase]] | ||
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[[Category: gadb complexed with iodide]] | [[Category: gadb complexed with iodide]] | ||
| - | ''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 16:26:58 2008'' |
Revision as of 14:27, 20 March 2008
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| , resolution 1.95Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , , and | ||||||
| Gene: | gadB (Escherichia coli) | ||||||
| Activity: | Glutamate decarboxylase, with EC number 4.1.1.15 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of Escherichia coli GadB in complex with iodide
Overview
Escherichia coli and other enterobacteria exploit the H+ -consuming reaction catalysed by glutamate decarboxylase to survive the stomach acidity before reaching the intestine. Here we show that chloride, extremely abundant in gastric secretions, is an allosteric activator producing a 10-fold increase in the decarboxylase activity at pH 5.6. Cooperativity and sensitivity to chloride were lost when the N-terminal 14 residues, involved in the formation of two triple-helix bundles, were deleted by mutagenesis. X-ray structures, obtained in the presence of the substrate analogue acetate, identified halide-binding sites at the base of each N-terminal helix, showed how halide binding is responsible for bundle stability and demonstrated that the interconversion between active and inactive forms of the enzyme is a stepwise process. We also discovered an entirely novel structure of the cofactor pyridoxal 5'-phosphate (aldamine) to be responsible for the reversibly inactivated enzyme. Our results link the entry of chloride ions, via the H+/Cl- exchange activities of ClC-ec1, to the trigger of the acid stress response in the cell when the intracellular proton concentration has not yet reached fatal values.
About this Structure
2DGM is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Escherichia coli acid resistance: pH-sensing, activation by chloride and autoinhibition in GadB., Gut H, Pennacchietti E, John RA, Bossa F, Capitani G, De Biase D, Grutter MG, EMBO J. 2006 Jun 7;25(11):2643-51. Epub 2006 May 4. PMID:16675957
Page seeded by OCA on Thu Mar 20 16:26:58 2008
Categories: Escherichia coli | Glutamate decarboxylase | Single protein | Capitani, G. | Gruetter, M G. | Gut, H. | ACY | FMT | IOD | PEG | PLP | Gadb complexed with iodide
