7tim
From Proteopedia
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|PDB= 7tim |SIZE=350|CAPTION= <scene name='initialview01'>7tim</scene>, resolution 1.9Å | |PDB= 7tim |SIZE=350|CAPTION= <scene name='initialview01'>7tim</scene>, resolution 1.9Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=PGH:PHOSPHOGLYCOLOHYDROXAMIC ACID'>PGH</scene> | + | |LIGAND= <scene name='pdbligand=PGH:PHOSPHOGLYCOLOHYDROXAMIC+ACID'>PGH</scene> |
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Triose-phosphate_isomerase Triose-phosphate isomerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.3.1.1 5.3.1.1] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Triose-phosphate_isomerase Triose-phosphate isomerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.3.1.1 5.3.1.1] </span> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=7tim FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7tim OCA], [http://www.ebi.ac.uk/pdbsum/7tim PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=7tim RCSB]</span> | ||
}} | }} | ||
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[[Category: Ringe, D.]] | [[Category: Ringe, D.]] | ||
[[Category: Seaton, B A.]] | [[Category: Seaton, B A.]] | ||
| - | [[Category: PGH]] | ||
[[Category: intramolecular oxidoreductase]] | [[Category: intramolecular oxidoreductase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 05:44:46 2008'' |
Revision as of 02:44, 31 March 2008
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| , resolution 1.9Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Activity: | Triose-phosphate isomerase, with EC number 5.3.1.1 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
STRUCTURE OF THE TRIOSEPHOSPHATE ISOMERASE-PHOSPHOGLYCOLOHYDROXAMATE COMPLEX: AN ANALOGUE OF THE INTERMEDIATE ON THE REACTION PATHWAY
Overview
The glycolytic enzyme triosephosphate isomerase (TIM) catalyzes the interconversion of the three-carbon sugars dihydroxyacetone phosphate (DHAP) and D-glyceraldehyde 3-phosphate (GAP) at a rate limited by the diffusion of substrate to the enzyme. We have solved the three-dimensional structure of TIM complexed with a reactive intermediate analogue, phosphoglycolohydroxamate (PGH), at 1.9-A resolution and have refined the structure to an R-factor of 18%. Analysis of the refined structure reveals the geometry of the active-site residues and the interactions they make with the inhibitor and, by analogy, the substrates. The structure is consistent with an acid-base mechanism in which the carboxylate of Glu-165 abstracts a proton from carbon while His-95 donates a proton to oxygen to form an enediol (or enediolate) intermediate. The conformation of the bound substrate stereoelectronically favors proton transfer from substrate carbon to the syn orbital of Glu-165. The crystal structure suggests that His-95 is neutral rather than cationic in the ground state and therefore would have to function as an imidazole acid instead of the usual imidazolium. Lys-12 is oriented so as to polarize the substrate oxygens by hydrogen bonding and/or electrostatic interaction, providing stabilization for the charged transition state. Asn-10 may play a similar role.
About this Structure
7TIM is a Single protein structure of sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Structure of the triosephosphate isomerase-phosphoglycolohydroxamate complex: an analogue of the intermediate on the reaction pathway., Davenport RC, Bash PA, Seaton BA, Karplus M, Petsko GA, Ringe D, Biochemistry. 1991 Jun 18;30(24):5821-6. PMID:2043623
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