3eib: Difference between revisions
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< | ==Crystal structure of K270N variant of LL-diaminopimelate aminotransferase from Arabidopsis thaliana== | ||
<StructureSection load='3eib' size='340' side='right'caption='[[3eib]], [[Resolution|resolution]] 1.85Å' scene=''> | |||
You may | == Structural highlights == | ||
<table><tr><td colspan='2'>[[3eib]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Arabidopsis_thaliana Arabidopsis thaliana]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3EIB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3EIB 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]] 1.85Å</td></tr> | |||
-- | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=3eib FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3eib OCA], [https://pdbe.org/3eib PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3eib RCSB], [https://www.ebi.ac.uk/pdbsum/3eib PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3eib ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/DAPAT_ARATH DAPAT_ARATH] Required for lysine biosynthesis. Catalyzes the direct conversion of tetrahydrodipicolinate to LL-diaminopimelate, a reaction that requires three enzymes in E.coli. Not active with meso-diaminopimelate, lysine or ornithine as substrates.<ref>PMID:16361515</ref> <ref>PMID:21435399</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/ei/3eib_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=3eib ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
LL-Diaminopimelate aminotransferase (LL-DAP-AT), a pyridoxal phosphate (PLP)-dependent enzyme in the lysine biosynthetic pathways of plants and Chlamydia, is a potential target for the development of herbicides or antibiotics. This homodimeric enzyme converts L-tetrahydrodipicolinic acid (THDP) directly to LL-DAP using L-glutamate as the source of the amino group. Earlier, we described the 3D structures of native and malate-bound LL-DAP-AT from Arabidopsis thaliana (AtDAP-AT). Seven additional crystal structures of AtDAP-AT and its variants are reported here as part of an investigation into the mechanism of substrate recognition and catalysis. Two structures are of AtDAP-AT with reduced external aldimine analogues: N-(5'-phosphopyridoxyl)-L-glutamate (PLP-Glu) and N-(5'-phosphopyridoxyl)- LL-Diaminopimelate (PLP-DAP) bound in the active site. Surprisingly, they reveal that both L-glutamate and LL-DAP are recognized in a very similar fashion by the same sets of amino acid residues; both molecules adopt twisted V-shaped conformations. With both substrates, the alpha-carboxylates are bound in a salt bridge with Arg404, whereas the distal carboxylates are recognized via hydrogen bonds to the well-conserved side chains of Tyr37, Tyr125 and Lys129. The distal C(epsilon) amino group of LL-DAP is specifically recognized by several non-covalent interactions with residues from the other subunit (Asn309*, Tyr94*, Gly95*, and Glu97* (Amino acid designators followed by an asterisk (*) indicate that the residues originate in the other subunit of the dimer)) and by three bound water molecules. Two catalytically inactive variants of AtDAP-AT were created via site-directed mutagenesis of the active site lysine (K270N and K270Q). The structures of these variants permitted the observation of the unreduced external aldimines of PLP with L-glutamate and with LL-DAP in the active site, and revealed differences in the torsion angle about the PLP-substrate bond. Lastly, an apo-AtDAP-AT structure missing PLP revealed details of conformational changes induced by PLP binding and substrate entry into the active site. | |||
Mechanism of substrate recognition and PLP-induced conformational changes in LL-diaminopimelate aminotransferase from Arabidopsis thaliana.,Watanabe N, Clay MD, van Belkum MJ, Cherney MM, Vederas JC, James MN J Mol Biol. 2008 Dec 31;384(5):1314-29. Epub 2008 Oct 15. PMID:18952095<ref>PMID:18952095</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 3eib" style="background-color:#fffaf0;"></div> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Arabidopsis thaliana]] | [[Category: Arabidopsis thaliana]] | ||
[[Category: | [[Category: Large Structures]] | ||
[[Category: Cherney MM]] | |||
[[Category: Clay MD]] | |||
[[Category: Cherney | [[Category: James MNG]] | ||
[[Category: Clay | [[Category: Vederas JC]] | ||
[[Category: James | [[Category: Watanabe N]] | ||
[[Category: Vederas | [[Category: Van Belkum MJ]] | ||
[[Category: Watanabe | |||
[[Category: | |||
Latest revision as of 16:03, 30 August 2023
Crystal structure of K270N variant of LL-diaminopimelate aminotransferase from Arabidopsis thalianaCrystal structure of K270N variant of LL-diaminopimelate aminotransferase from Arabidopsis thaliana
Structural highlights
FunctionDAPAT_ARATH Required for lysine biosynthesis. Catalyzes the direct conversion of tetrahydrodipicolinate to LL-diaminopimelate, a reaction that requires three enzymes in E.coli. Not active with meso-diaminopimelate, lysine or ornithine as substrates.[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 PubMedLL-Diaminopimelate aminotransferase (LL-DAP-AT), a pyridoxal phosphate (PLP)-dependent enzyme in the lysine biosynthetic pathways of plants and Chlamydia, is a potential target for the development of herbicides or antibiotics. This homodimeric enzyme converts L-tetrahydrodipicolinic acid (THDP) directly to LL-DAP using L-glutamate as the source of the amino group. Earlier, we described the 3D structures of native and malate-bound LL-DAP-AT from Arabidopsis thaliana (AtDAP-AT). Seven additional crystal structures of AtDAP-AT and its variants are reported here as part of an investigation into the mechanism of substrate recognition and catalysis. Two structures are of AtDAP-AT with reduced external aldimine analogues: N-(5'-phosphopyridoxyl)-L-glutamate (PLP-Glu) and N-(5'-phosphopyridoxyl)- LL-Diaminopimelate (PLP-DAP) bound in the active site. Surprisingly, they reveal that both L-glutamate and LL-DAP are recognized in a very similar fashion by the same sets of amino acid residues; both molecules adopt twisted V-shaped conformations. With both substrates, the alpha-carboxylates are bound in a salt bridge with Arg404, whereas the distal carboxylates are recognized via hydrogen bonds to the well-conserved side chains of Tyr37, Tyr125 and Lys129. The distal C(epsilon) amino group of LL-DAP is specifically recognized by several non-covalent interactions with residues from the other subunit (Asn309*, Tyr94*, Gly95*, and Glu97* (Amino acid designators followed by an asterisk (*) indicate that the residues originate in the other subunit of the dimer)) and by three bound water molecules. Two catalytically inactive variants of AtDAP-AT were created via site-directed mutagenesis of the active site lysine (K270N and K270Q). The structures of these variants permitted the observation of the unreduced external aldimines of PLP with L-glutamate and with LL-DAP in the active site, and revealed differences in the torsion angle about the PLP-substrate bond. Lastly, an apo-AtDAP-AT structure missing PLP revealed details of conformational changes induced by PLP binding and substrate entry into the active site. Mechanism of substrate recognition and PLP-induced conformational changes in LL-diaminopimelate aminotransferase from Arabidopsis thaliana.,Watanabe N, Clay MD, van Belkum MJ, Cherney MM, Vederas JC, James MN J Mol Biol. 2008 Dec 31;384(5):1314-29. Epub 2008 Oct 15. PMID:18952095[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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