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| | ==Solution NMR studies of the dimeric regulatory subunit IlvN of the E.coli Acetohydroxyacid synthase I (AHAS I)== | | ==Solution NMR studies of the dimeric regulatory subunit IlvN of the E.coli Acetohydroxyacid synthase I (AHAS I)== |
| - | <StructureSection load='2lvw' size='340' side='right' caption='[[2lvw]], [[NMR_Ensembles_of_Models | 20 NMR models]]' scene=''> | + | <StructureSection load='2lvw' size='340' side='right'caption='[[2lvw]]' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[2lvw]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Escherichia_coli_k-12 Escherichia coli k-12]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2LVW OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2LVW FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[2lvw]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2LVW OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2LVW FirstGlance]. <br> |
| - | </td></tr><tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">b3670, ilvN, JW3645 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=83333 Escherichia coli K-12])</td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Acetolactate_synthase Acetolactate synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.2.1.6 2.2.1.6] </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=2lvw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2lvw OCA], [https://pdbe.org/2lvw PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2lvw RCSB], [https://www.ebi.ac.uk/pdbsum/2lvw PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2lvw ProSAT]</span></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=2lvw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2lvw OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2lvw RCSB], [http://www.ebi.ac.uk/pdbsum/2lvw PDBsum]</span></td></tr> | + | |
| | </table> | | </table> |
| - | <div style="background-color:#fffaf0;">
| + | == Function == |
| - | == Publication Abstract from PubMed == | + | [https://www.uniprot.org/uniprot/ILVN_ECOLI ILVN_ECOLI] |
| - | The solution structure of IlvN, the regulatory subunit of Escherichia coli acetohydroxyacid synthase I, in the valine-bound form has been determined using high-resolution multidimensional, multinuclear nuclear magnetic resonance (NMR) methods. IlvN in the presence or absence of the effector molecule is present as a 22.5 kDa dimeric molecule. The ensemble of 20 low-energy structures shows a backbone root-mean-square deviation of 0.73 +/- 0.13 A and a root-mean-square deviation of 1.16 +/- 0.13 A for all heavy atoms. Furthermore, more than 98% of the backbone phi and psi dihedral angles occupy the allowed and additionally allowed regions of the Ramachandran map, which is indicative of the fact that the structures are of high stereochemical quality. Each protomer exhibits a betaalphabetabetaalphabetaalpha topology that is a characteristic feature of the ACT domain seen in metabolic enzymes. In the valine-bound form, IlvN exists apparently as a single conformer. In the free form, IlvN exists as a mixture of conformational states that are in intermediate exchange on the NMR time scale. Thus, a large shift in the conformational equilibrium is observed upon going from the free form to the bound form. The structure of the valine-bound form of IlvN was found to be similar to that of the ACT domain of the unliganded form of IlvH. Comparisons of the structures of the unliganded forms of these proteins suggest significant differences. The structural and conformational properties of IlvN determined here have allowed a better understanding of the mechanism of regulation of branched chain amino acid biosynthesis.
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| - | The coil-to-helix transition in IlvN regulates the allosteric control of Escherichia coli acetohydroxyacid synthase I.,Karanth NM, Sarma SP Biochemistry. 2013 Jan 8;52(1):70-83. doi: 10.1021/bi301415m. Epub 2012 Dec 21. PMID:23205845<ref>PMID:23205845</ref>
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| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
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| - | </div>
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| - | == References ==
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| - | <references/>
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| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Acetolactate synthase]]
| + | [[Category: Escherichia coli K-12]] |
| - | [[Category: Escherichia coli k-12]] | + | [[Category: Large Structures]] |
| - | [[Category: Karanth, M N]] | + | [[Category: Karanth MN]] |
| - | [[Category: Sarma, S P]] | + | [[Category: Sarma SP]] |
| - | [[Category: Act domain]] | + | |
| - | [[Category: Aha]]
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| - | [[Category: Branched chain amino acid biosynthesis]]
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| - | [[Category: Ilvn]]
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| - | [[Category: Regulatory subunit]]
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| - | [[Category: Transferase]]
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| - | [[Category: Valine]]
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