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| | ==THREONINE DEAMINASE (BIOSYNTHETIC) FROM E. COLI== | | ==THREONINE DEAMINASE (BIOSYNTHETIC) FROM E. COLI== |
| - | <StructureSection load='1tdj' size='340' side='right' caption='[[1tdj]], [[Resolution|resolution]] 2.80Å' scene=''> | + | <StructureSection load='1tdj' size='340' side='right'caption='[[1tdj]], [[Resolution|resolution]] 2.80Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[1tdj]] is a 1 chain structure with 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=1TDJ OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1TDJ FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[1tdj]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1TDJ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1TDJ FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.8Å</td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Threonine_ammonia-lyase Threonine ammonia-lyase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.3.1.19 4.3.1.19] </span></td></tr> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene></td></tr> |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1tdj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1tdj OCA], [http://pdbe.org/1tdj PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1tdj RCSB], [http://www.ebi.ac.uk/pdbsum/1tdj PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1tdj ProSAT]</span></td></tr> | + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1tdj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1tdj OCA], [https://pdbe.org/1tdj PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1tdj RCSB], [https://www.ebi.ac.uk/pdbsum/1tdj PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1tdj ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/ILVA_ECOLI ILVA_ECOLI]] Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2-ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.<ref>PMID:13405870</ref> | + | [https://www.uniprot.org/uniprot/ILVA_ECOLI ILVA_ECOLI] Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2-ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.<ref>PMID:13405870</ref> |
| | == Evolutionary Conservation == | | == Evolutionary Conservation == |
| | [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
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| | <jmolCheckbox> | | <jmolCheckbox> |
| | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/td/1tdj_consurf.spt"</scriptWhenChecked> | | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/td/1tdj_consurf.spt"</scriptWhenChecked> |
| - | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | + | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked> |
| | <text>to colour the structure by Evolutionary Conservation</text> | | <text>to colour the structure by Evolutionary Conservation</text> |
| | </jmolCheckbox> | | </jmolCheckbox> |
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| | ==See Also== | | ==See Also== |
| - | *[[Deaminase|Deaminase]] | + | *[[Deaminase 3D structures|Deaminase 3D structures]] |
| | == References == | | == References == |
| | <references/> | | <references/> |
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| | </StructureSection> | | </StructureSection> |
| | [[Category: Escherichia coli]] | | [[Category: Escherichia coli]] |
| - | [[Category: Threonine ammonia-lyase]] | + | [[Category: Large Structures]] |
| - | [[Category: Eisenstein, E]] | + | [[Category: Eisenstein E]] |
| - | [[Category: Gallagher, D T]] | + | [[Category: Gallagher DT]] |
| - | [[Category: Gilliland, G L]] | + | [[Category: Gilliland GL]] |
| - | [[Category: Xiao, G]] | + | [[Category: Xiao G]] |
| - | [[Category: Allostery]]
| + | |
| - | [[Category: Cooperative]]
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| - | [[Category: Isoleucine biosynthesis]]
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| - | [[Category: Pyridoxal phosphate]]
| + | |
| - | [[Category: Regulation]]
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| - | [[Category: Tetramer]]
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| Structural highlights
Function
ILVA_ECOLI Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2-ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.[1]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
BACKGROUND: Feedback inhibition of biosynthetic threonine deaminase (TD) from Escherichia coli provided one of the earliest examples of protein-based metabolic regulation. Isoleucine, the pathway end-product, and valine, the product of a parallel pathway, serve as allosteric inhibitor and activator, respectively. This enzyme is thus a useful model system for studying the structural basis of allosteric control mechanisms. RESULTS: We report the crystal structure of TD at 2.8 A resolution. The tetramer has 222 symmetry, with C-terminal regulatory domains projecting out from a core of catalytic PLP-containing N-terminal domains. The subunits, and especially the regulatory domains, associate extensively to form dimers, which associate less extensively to form the tetramer. Within the dimer, each monomer twists approximately 150 degrees around a thin neck between the domains to place its catalytic domain adjacent to the regulatory domain of the other subunit. CONCLUSIONS: The structure of TD and its comparison with related structures and other data lead to the tentative identification of the regulatory binding site and revealed several implications for the allosteric mechanism. This work prepares the way for detailed structure/function studies of the complex allosteric behaviour of this enzyme.
Structure and control of pyridoxal phosphate dependent allosteric threonine deaminase.,Gallagher DT, Gilliland GL, Xiao G, Zondlo J, Fisher KE, Chinchilla D, Eisenstein E Structure. 1998 Apr 15;6(4):465-75. PMID:9562556[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ UMBARGER HE, BROWN B. Threonine deamination in Escherichia coli. II. Evidence for two L-threonine deaminases. J Bacteriol. 1957 Jan;73(1):105-12. PMID:13405870
- ↑ Gallagher DT, Gilliland GL, Xiao G, Zondlo J, Fisher KE, Chinchilla D, Eisenstein E. Structure and control of pyridoxal phosphate dependent allosteric threonine deaminase. Structure. 1998 Apr 15;6(4):465-75. PMID:9562556
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