2olq: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:2olq.jpg|left|200px]] | [[Image:2olq.jpg|left|200px]] | ||
'''How Does an Enzyme Recognize CO2?''' | {{Structure | ||
|PDB= 2olq |SIZE=350|CAPTION= <scene name='initialview01'>2olq</scene>, resolution 1.940Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ATP:ADENOSINE-5'-TRIPHOSPHATE'>ATP</scene> and <scene name='pdbligand=CO2:CARBON DIOXIDE'>CO2</scene> | |||
|ACTIVITY= [http://en.wikipedia.org/wiki/Phosphoenolpyruvate_carboxykinase_(ATP) Phosphoenolpyruvate carboxykinase (ATP)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.1.49 4.1.1.49] | |||
|GENE= pckA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | |||
}} | |||
'''How Does an Enzyme Recognize CO2?''' | |||
==Overview== | ==Overview== | ||
| Line 7: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
2OLQ is a [ | 2OLQ 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=2OLQ OCA]. | ||
==Reference== | ==Reference== | ||
How does an enzyme recognize CO2?, Cotelesage JJ, Puttick J, Goldie H, Rajabi B, Novakovski B, Delbaere LT, Int J Biochem Cell Biol. 2007;39(6):1204-10. Epub 2007 Mar 30. PMID:[http:// | How does an enzyme recognize CO2?, Cotelesage JJ, Puttick J, Goldie H, Rajabi B, Novakovski B, Delbaere LT, Int J Biochem Cell Biol. 2007;39(6):1204-10. Epub 2007 Mar 30. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17475535 17475535] | ||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Phosphoenolpyruvate carboxykinase (ATP)]] | [[Category: Phosphoenolpyruvate carboxykinase (ATP)]] | ||
| Line 27: | Line 36: | ||
[[Category: phosphoenolpyruvate carboxykinase]] | [[Category: phosphoenolpyruvate carboxykinase]] | ||
''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 18:01:25 2008'' | ||
Revision as of 16:01, 20 March 2008
| |||||||||||||
| 2olq, resolution 1.940Å | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ligands: | MN, MG, ATP and CO2 | ||||||||||||
| Gene: | pckA (Escherichia coli) | ||||||||||||
| Activity: | Phosphoenolpyruvate carboxykinase (ATP), with EC number 4.1.1.49 | ||||||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||||||
How Does an Enzyme Recognize CO2?
Overview
Phosphoenolpyruvate carboxykinase (PCK) reversibly catalyzes the carboxylation of phosphoenolpyruvate to oxaloacetate. Carbon dioxide, and not bicarbonate ion, is the substrate utilized. Assays of the carboxylation reaction show that initial velocities are 7.6-fold higher when CO(2) is used instead of HCO(3)(-). Two Escherichia coli PCK-CO(2) crystal structures are presented here. The location of CO(2) is the same for both structures; however the orientation of CO(2) is significantly different, likely from the presence of a manganese ion in one of the structures. PCK and the other three known protein-CO(2) crystal structure complexes have been compared; all have CO(2) hydrogen bonding with a basic amino acid side chain (Arg65 or Lys213 in PCK), likely to polarize CO(2) to make the central carbon atom more electrophilic and thus more reactive. Kinetic studies found that the PCK mutant Arg65Gln increased the K(M) for substrates PEP and oxaloacetate but not for CO(2). The unchanged K(M) for CO(2) can be explained since the Arg65Gln mutant likely maintains a hydrogen bond to one of the oxygen atoms of carbon dioxide.
About this Structure
2OLQ is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
How does an enzyme recognize CO2?, Cotelesage JJ, Puttick J, Goldie H, Rajabi B, Novakovski B, Delbaere LT, Int J Biochem Cell Biol. 2007;39(6):1204-10. Epub 2007 Mar 30. PMID:17475535
Page seeded by OCA on Thu Mar 20 18:01:25 2008
