1tth
From Proteopedia
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- | [[Image:1tth.gif|left|200px]] | + | [[Image:1tth.gif|left|200px]] |
- | + | ||
- | '''Aspartate Transcarbamoylase Catalytic Chain Mutant Glu50Ala Complexed with N-(Phosphonacetyl-L-Aspartate) (PALA)''' | + | {{Structure |
+ | |PDB= 1tth |SIZE=350|CAPTION= <scene name='initialview01'>1tth</scene>, resolution 2.80Å | ||
+ | |SITE= | ||
+ | |LIGAND= <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene> and <scene name='pdbligand=PAL:N-(PHOSPHONACETYL)-L-ASPARTIC ACID'>PAL</scene> | ||
+ | |ACTIVITY= [http://en.wikipedia.org/wiki/Aspartate_carbamoyltransferase Aspartate carbamoyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.3.2 2.1.3.2] | ||
+ | |GENE= PYRB, B4245, C5345, Z5856, ECS5222, SF4245, S4507 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]), PYRI, B4244, C5344, Z5855, ECS5221 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | ||
+ | }} | ||
+ | |||
+ | '''Aspartate Transcarbamoylase Catalytic Chain Mutant Glu50Ala Complexed with N-(Phosphonacetyl-L-Aspartate) (PALA)''' | ||
+ | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
- | 1TTH is a [ | + | 1TTH is a [[Protein complex]] structure of sequences 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=1TTH OCA]. |
==Reference== | ==Reference== | ||
- | Monitoring the transition from the T to the R state in E.coli aspartate transcarbamoylase by X-ray crystallography: crystal structures of the E50A mutant enzyme in four distinct allosteric states., Stieglitz K, Stec B, Baker DP, Kantrowitz ER, J Mol Biol. 2004 Aug 13;341(3):853-68. PMID:[http:// | + | Monitoring the transition from the T to the R state in E.coli aspartate transcarbamoylase by X-ray crystallography: crystal structures of the E50A mutant enzyme in four distinct allosteric states., Stieglitz K, Stec B, Baker DP, Kantrowitz ER, J Mol Biol. 2004 Aug 13;341(3):853-68. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/15288791 15288791] |
[[Category: Aspartate carbamoyltransferase]] | [[Category: Aspartate carbamoyltransferase]] | ||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
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[[Category: site-specific mutagenesis]] | [[Category: site-specific mutagenesis]] | ||
- | ''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 14:22:55 2008'' |
Revision as of 12:22, 20 March 2008
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, resolution 2.80Å | |||||||
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Ligands: | and | ||||||
Gene: | PYRB, B4245, C5345, Z5856, ECS5222, SF4245, S4507 (Escherichia coli), PYRI, B4244, C5344, Z5855, ECS5221 (Escherichia coli) | ||||||
Activity: | Aspartate carbamoyltransferase, with EC number 2.1.3.2 | ||||||
Coordinates: | save as pdb, mmCIF, xml |
Aspartate Transcarbamoylase Catalytic Chain Mutant Glu50Ala Complexed with N-(Phosphonacetyl-L-Aspartate) (PALA)
Overview
A detailed description of the transition that allosteric enzymes undergo constitutes a major challenge in structural biology. We have succeeded in trapping four distinct allosteric states of a mutant enzyme of Escherichia coli aspartate transcarbomylase and determining their structures by X-ray crystallography. The mutant version of aspartate transcarbamoylase in which Glu50 in the catalytic chains was replaced by Ala destabilizes the native R state and shifts the equilibrium towards the T state. This behavior allowed the use of substrate analogs such as phosphonoacetamide and malonate to trap the enzyme in T-like and R-like structures that are distinct from the T-state structure of the wild-type enzyme (as represented by the structure of the enzyme with CTP bound and the R-state structure as represented by the structure with N-(phosphonacetyl)-L-aspartate bound). These structures shed light on the nature and the order of internal structural rearrangements during the transition from the T to the R state. They also suggest an explanation for diminished activity of the E50A enzyme and for the change in reaction mechanism from ordered to random for this mutant enzyme.
About this Structure
1TTH is a Protein complex structure of sequences from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Monitoring the transition from the T to the R state in E.coli aspartate transcarbamoylase by X-ray crystallography: crystal structures of the E50A mutant enzyme in four distinct allosteric states., Stieglitz K, Stec B, Baker DP, Kantrowitz ER, J Mol Biol. 2004 Aug 13;341(3):853-68. PMID:15288791
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