View source for 2ggh


==The mutant A68C-D72C-NLQ of Deinococcus Radiodurans Nacylamino acid racemase==
<StructureSection load='2ggh' size='340' side='right'caption='[[2ggh]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2ggh]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Deinococcus_radiodurans Deinococcus radiodurans]. This structure supersedes the now removed PDB entries [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=2fkr 2fkr] and [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=2ba8 2ba8]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2GGH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2GGH 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]] 2.2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NLQ:N~2~-ACETYL-L-GLUTAMINE'>NLQ</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=2ggh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ggh OCA], [https://pdbe.org/2ggh PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ggh RCSB], [https://www.ebi.ac.uk/pdbsum/2ggh PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ggh ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/NSAR_DEIRA NSAR_DEIRA] Acts as a N-succinylamino acid racemase (NSAR) that catalyzes the racemization of N-succinyl-L-phenylglycine and N-succinyl-D/L-phenylalanine (PubMed:24872444, PubMed:25875730). Can catalyze the racemization of a broad range of N-acylamino acids, including N-acetyl-D/L-methionine, N-acetyl-D/L-phenylalanine, N-acetyl-L-glutamine, N-acetyl-L-tryptophan, N-acetyl-L-leucine, N-formyl-D-methionine, N-formyl-D-norleucine, N-carbamoyl-D-methionine and N-carbamoyl-D-norleucine (PubMed:15313614, PubMed:16650857, PubMed:25875730). Also converts 2-succinyl-6-hydroxy-2,4-cyclohexadiene-1-carboxylate (SHCHC) to 2-succinylbenzoate (OSB) (PubMed:24872444). Catalyzes both N-succinylamino acid racemization and OSB synthesis at equivalent rates (PubMed:24872444). However, NSAR activity is probably the protein's biological function, because menaquinone biosynthesis genes are missing in this species (Probable).<ref>PMID:15313614</ref> <ref>PMID:16650857</ref> <ref>PMID:24872444</ref> <ref>PMID:25875730</ref> <ref>PMID:16740275</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/gg/2ggh_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=2ggh ConSurf].
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== Publication Abstract from PubMed ==
N-Acylamino acid racemase (NAAAR) and N-carbamoyl-D-amino-acid amidohydrolase (D-NCAase) are important biocatalysts for producing enantiopure alpha-amino acids. NAAAR forms an octameric assembly and displays induced fit movements upon substrate binding, while D-NCAase is a tetramer that does not change conformation in the presence of a ligand. To investigate the effects of introducing potentially stabilizing S-S bridges in these different multimeric enzymes, cysteine residues predicted to form inter or intra-subunit disulfide bonds were introduced by site-directed mutagenesis. Inter-subunit S-S bonds were formed in two NAAAR variants (A68C-D72C and P60C-Y100C) and two d-NCAase variants (A302C and P295C-F304C). Intra-subunit S-S bonds were formed in two additional NAAAR variants (E149C-A182C and V265C). Crystal structures of NAAARs variants show limited deviations from the wild-type overall tertiary structure. An apo A68C-D72C subunit differs from the wild-type enzyme, in which it has an ordered lid loop, resembling ligand-bound NAAAR. The structures of A222C and A302C D-NCAases are nearly identical to the wild-type enzyme. All mutants with inter-subunit bridges had increases in thermostability. Compared with the wild-type enzyme, A68C-D72C NAAAR showed similar kcat/Km ratios, whereas mutant D-NCAases demonstrated increased kcat/Km ratios at high temperatures (A302C: 4.2-fold at 65 degrees C). Furthermore, molecular dynamic simulations reveal that A302C substantially sustains the fine-tuned catalytic site as temperature increases, achieving enhanced activity.

Structure-stability-activity relationship in covalently cross-linked N-carbamoyl D-amino acid amidohydrolase and N-acylamino acid racemase.,Chiu WC, You JY, Liu JS, Hsu SK, Hsu WH, Shih CH, Hwang JK, Wang WC J Mol Biol. 2006 Jun 9;359(3):741-53. Epub 2006 Apr 18. PMID:16650857<ref>PMID:16650857</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Deinococcus radiodurans]]
[[Category: Large Structures]]
[[Category: Chiu WC]]
[[Category: Wang WC]]