2csm: Difference between revisions
No edit summary |
No edit summary |
||
| Line 4: | Line 4: | ||
==Overview== | ==Overview== | ||
The crystal structure of the tyrosine-bound T state of allosteric yeast | The crystal structure of the tyrosine-bound T state of allosteric yeast Saccharomyces cerevisiae chorismate mutase was solved by molecular replacement at a resolution of 2.8 angstroms using a monomer of the R-state structure as the search model. The allosteric inhibitor tyrosine was found to bind in the T state at the same binding site as the allosteric activator tryptophan binds in the R state, thus defining one regulatory binding site for each monomer. Activation by tryptophan is caused by the larger steric size of its side chain, thereby pushing apart the allosteric domain of one monomer and helix H8 of the catalytic domain of the other monomer. Inhibition is caused by polar contacts of tyrosine with Arg-75 and Arg-76 of one monomer and with Gly-141, Ser-142, and Thr-145 of the other monomer, thereby bringing the allosteric and catalytic domains closer together. The allosteric transition includes an 8 degree rotation of each of the two catalytic domains relative to the allosteric domains of each monomer (domain closure). Alternatively, this transition can be described as a 15 degree rotation of the catalytic domains of the dimer relative to each other. | ||
==About this Structure== | ==About this Structure== | ||
| Line 15: | Line 15: | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Hakansson, K.]] | [[Category: Hakansson, K.]] | ||
[[Category: Lipscomb, W | [[Category: Lipscomb, W N.]] | ||
[[Category: Straeter, N.]] | [[Category: Straeter, N.]] | ||
[[Category: TYR]] | [[Category: TYR]] | ||
| Line 21: | Line 21: | ||
[[Category: complex (isomerase/peptide)]] | [[Category: complex (isomerase/peptide)]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:52:07 2008'' | ||
Revision as of 17:52, 21 February 2008
|
TYR-BOUND T-STATE OF YEAST CHORISMATE MUTASE
OverviewOverview
The crystal structure of the tyrosine-bound T state of allosteric yeast Saccharomyces cerevisiae chorismate mutase was solved by molecular replacement at a resolution of 2.8 angstroms using a monomer of the R-state structure as the search model. The allosteric inhibitor tyrosine was found to bind in the T state at the same binding site as the allosteric activator tryptophan binds in the R state, thus defining one regulatory binding site for each monomer. Activation by tryptophan is caused by the larger steric size of its side chain, thereby pushing apart the allosteric domain of one monomer and helix H8 of the catalytic domain of the other monomer. Inhibition is caused by polar contacts of tyrosine with Arg-75 and Arg-76 of one monomer and with Gly-141, Ser-142, and Thr-145 of the other monomer, thereby bringing the allosteric and catalytic domains closer together. The allosteric transition includes an 8 degree rotation of each of the two catalytic domains relative to the allosteric domains of each monomer (domain closure). Alternatively, this transition can be described as a 15 degree rotation of the catalytic domains of the dimer relative to each other.
About this StructureAbout this Structure
2CSM is a Single protein structure of sequence from Saccharomyces cerevisiae with as ligand. Active as Chorismate mutase, with EC number 5.4.99.5 Known structural/functional Sites: and . Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of the T state of allosteric yeast chorismate mutase and comparison with the R state., Strater N, Hakansson K, Schnappauf G, Braus G, Lipscomb WN, Proc Natl Acad Sci U S A. 1996 Apr 16;93(8):3330-4. PMID:8622937
Page seeded by OCA on Thu Feb 21 16:52:07 2008