1eua: Difference between revisions
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[[Image:1eua.gif|left|200px]] | [[Image:1eua.gif|left|200px]] | ||
'''SCHIFF BASE INTERMEDIATE IN KDPG ALDOLASE FROM ESCHERICHIA COLI''' | {{Structure | ||
|PDB= 1eua |SIZE=350|CAPTION= <scene name='initialview01'>1eua</scene>, resolution 1.95Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene> and <scene name='pdbligand=PYR:PYRUVIC ACID'>PYR</scene> | |||
|ACTIVITY= [http://en.wikipedia.org/wiki/2-dehydro-3-deoxy-phosphogluconate_aldolase 2-dehydro-3-deoxy-phosphogluconate aldolase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.2.14 4.1.2.14] | |||
|GENE= | |||
}} | |||
'''SCHIFF BASE INTERMEDIATE IN KDPG ALDOLASE FROM ESCHERICHIA COLI''' | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
1EUA is a [ | 1EUA 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=1EUA OCA]. | ||
==Reference== | ==Reference== | ||
Covalent intermediate trapped in 2-keto-3-deoxy-6- phosphogluconate (KDPG) aldolase structure at 1.95-A resolution., Allard J, Grochulski P, Sygusch J, Proc Natl Acad Sci U S A. 2001 Mar 27;98(7):3679-84. PMID:[http:// | Covalent intermediate trapped in 2-keto-3-deoxy-6- phosphogluconate (KDPG) aldolase structure at 1.95-A resolution., Allard J, Grochulski P, Sygusch J, Proc Natl Acad Sci U S A. 2001 Mar 27;98(7):3679-84. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/11274385 11274385] | ||
[[Category: 2-dehydro-3-deoxy-phosphogluconate aldolase]] | [[Category: 2-dehydro-3-deoxy-phosphogluconate aldolase]] | ||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
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[[Category: trimer]] | [[Category: trimer]] | ||
''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 11:00:22 2008'' | ||
Revision as of 09:00, 20 March 2008
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| 1eua, resolution 1.95Å | |||||||||||||
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| Ligands: | ACT, SO4 and PYR | ||||||||||||
| Activity: | 2-dehydro-3-deoxy-phosphogluconate aldolase, with EC number 4.1.2.14 | ||||||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||||||
SCHIFF BASE INTERMEDIATE IN KDPG ALDOLASE FROM ESCHERICHIA COLI
Overview
2-Keto-3-deoxy-6-phosphogluconate (KDPG) aldolase catalyzes the reversible cleavage of KDPG to pyruvate and glyceraldehyde-3-phosphate. The enzyme is a class I aldolase whose reaction mechanism involves formation of Schiff base intermediates between Lys-133 and a keto substrate. A covalent adduct was trapped by flash freezing KDPG aldolase crystals soaked with 10 mM pyruvate in acidic conditions at pH 4.6. Structure determination to 1.95-A resolution showed that pyruvate had undergone nucleophilic attack with Lys-133, forming a protonated carbinolamine intermediate, a functional Schiff base precursor, which was stabilized by hydrogen bonding with active site residues. Carbinolamine interaction with Glu-45 indicates general base catalysis of several rate steps. Stereospecific addition is ensured by aromatic interaction of Phe-135 with the pyruvate methyl group. In the native structure, Lys-133 donates all of its hydrogen bonds, indicating the presence of an epsilon-ammonium salt group. Nucleophilic activation is postulated to occur by proton transfer in the monoprotonated zwitterionic pair (Glu-45/Lys-133). Formation of the zwitterionic pair requires prior side chain rearrangement by protonated Lys-133 to displace a water molecule, hydrogen bonded to the zwitterionic residues.
About this Structure
1EUA is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Covalent intermediate trapped in 2-keto-3-deoxy-6- phosphogluconate (KDPG) aldolase structure at 1.95-A resolution., Allard J, Grochulski P, Sygusch J, Proc Natl Acad Sci U S A. 2001 Mar 27;98(7):3679-84. PMID:11274385
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