2vc6: Difference between revisions
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< | ==Structure of MosA from S. meliloti with pyruvate bound== | ||
<StructureSection load='2vc6' size='340' side='right'caption='[[2vc6]], [[Resolution|resolution]] 1.95Å' scene=''> | |||
You may | == Structural highlights == | ||
<table><tr><td colspan='2'>[[2vc6]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Sinorhizobium_meliloti Sinorhizobium meliloti]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2VC6 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2VC6 FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.95Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=KPI:(2S)-2-AMINO-6-[(1-HYDROXY-1-OXO-PROPAN-2-YLIDENE)AMINO]HEXANOIC+ACID'>KPI</scene></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=2vc6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2vc6 OCA], [https://pdbe.org/2vc6 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2vc6 RCSB], [https://www.ebi.ac.uk/pdbsum/2vc6 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2vc6 ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/DAPA_RHIML DAPA_RHIML] Catalyzes the condensation of (S)-aspartate-beta-semialdehyde [(S)-ASA] and pyruvate to 4-hydroxy-tetrahydrodipicolinate (HTPA).<ref>PMID:14672649</ref> <ref>PMID:18536061</ref> | |||
== Evolutionary Conservation == | |||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/vc/2vc6_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2vc6 ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
MosA is an enzyme from Sinorhizobium meliloti L5-30, a beneficial soil bacterium that forms a symbiotic relationship with leguminous plants. MosA was proposed to catalyze the conversion of scyllo-inosamine to 3-O-methyl-scyllo-inosamine (compounds known as rhizopines), despite the MosA sequence showing a strong resemblance to dihydrodipicolinate synthase (DHDPS) sequences rather than to methyltransferases. Our laboratory has already shown that MosA is an efficient catalyst of the DHDPS reaction. Here we report the structure of MosA, solved to 1.95 A resolution, which resembles previously reported DHDPS structures. In this structure Lys161 forms a Schiff base adduct with pyruvate, consistent with the DHDPS mechanism. We have synthesized both known rhizopines and investigated their ability to interact with MosA in the presence and absence of methyl donors. No MosA-catalyzed methyltransferase activity is observed in the presence of scyllo-inosamine and S-adenosylmethionine (SAM). 2-Oxobutyrate can form a Schiff base with MosA, acting as a competitive inhibitor of MosA-catalyzed dihydrodipicolinate synthesis. It can be trapped on the enzyme by reaction with sodium borohydride, but does not act as a methyl donor. The presence of rhizopines does not affect the kinetics of dihydrodipicolinate synthesis. Isothermal titration calorimetry (ITC) shows no apparent interaction of MosA with rhizopines and SAM. Similar experiments with pyruvate as titrant demonstrate that the reversible Schiff base formation is largely entropically driven. This is the first use of ITC to study Schiff base formation between an enzyme and its substrate. | |||
Structural, functional and calorimetric investigation of MosA, a dihydrodipicolinate synthase from Sinorhizobium meliloti l5-30, does not support involvement in rhizopine biosynthesis.,Phenix CP, Nienaber K, Tam PH, Delbaere LT, Palmer DR Chembiochem. 2008 Jul 2;9(10):1591-602. PMID:18536061<ref>PMID:18536061</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 2vc6" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Dihydrodipicolinate synthase|Dihydrodipicolinate synthase]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
== | [[Category: Large Structures]] | ||
== | |||
< | |||
[[Category: | |||
[[Category: Sinorhizobium meliloti]] | [[Category: Sinorhizobium meliloti]] | ||
[[Category: Delbaere | [[Category: Delbaere LTJ]] | ||
[[Category: Nienaber | [[Category: Nienaber KH]] | ||
[[Category: Palmer | [[Category: Palmer DRJ]] | ||
[[Category: Phenix | [[Category: Phenix CP]] | ||
[[Category: Tam | [[Category: Tam PH]] | ||
Latest revision as of 18:14, 13 December 2023
Structure of MosA from S. meliloti with pyruvate boundStructure of MosA from S. meliloti with pyruvate bound
Structural highlights
FunctionDAPA_RHIML Catalyzes the condensation of (S)-aspartate-beta-semialdehyde [(S)-ASA] and pyruvate to 4-hydroxy-tetrahydrodipicolinate (HTPA).[1] [2] 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 PubMedMosA is an enzyme from Sinorhizobium meliloti L5-30, a beneficial soil bacterium that forms a symbiotic relationship with leguminous plants. MosA was proposed to catalyze the conversion of scyllo-inosamine to 3-O-methyl-scyllo-inosamine (compounds known as rhizopines), despite the MosA sequence showing a strong resemblance to dihydrodipicolinate synthase (DHDPS) sequences rather than to methyltransferases. Our laboratory has already shown that MosA is an efficient catalyst of the DHDPS reaction. Here we report the structure of MosA, solved to 1.95 A resolution, which resembles previously reported DHDPS structures. In this structure Lys161 forms a Schiff base adduct with pyruvate, consistent with the DHDPS mechanism. We have synthesized both known rhizopines and investigated their ability to interact with MosA in the presence and absence of methyl donors. No MosA-catalyzed methyltransferase activity is observed in the presence of scyllo-inosamine and S-adenosylmethionine (SAM). 2-Oxobutyrate can form a Schiff base with MosA, acting as a competitive inhibitor of MosA-catalyzed dihydrodipicolinate synthesis. It can be trapped on the enzyme by reaction with sodium borohydride, but does not act as a methyl donor. The presence of rhizopines does not affect the kinetics of dihydrodipicolinate synthesis. Isothermal titration calorimetry (ITC) shows no apparent interaction of MosA with rhizopines and SAM. Similar experiments with pyruvate as titrant demonstrate that the reversible Schiff base formation is largely entropically driven. This is the first use of ITC to study Schiff base formation between an enzyme and its substrate. Structural, functional and calorimetric investigation of MosA, a dihydrodipicolinate synthase from Sinorhizobium meliloti l5-30, does not support involvement in rhizopine biosynthesis.,Phenix CP, Nienaber K, Tam PH, Delbaere LT, Palmer DR Chembiochem. 2008 Jul 2;9(10):1591-602. PMID:18536061[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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