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| | ==Succinyl-CoA:acetate CoA-transferase (AarCH6) in complex with citrate (subunit B) or unliganded (subunit A)== | | ==Succinyl-CoA:acetate CoA-transferase (AarCH6) in complex with citrate (subunit B) or unliganded (subunit A)== |
| - | <StructureSection load='4eu3' size='340' side='right' caption='[[4eu3]], [[Resolution|resolution]] 1.58Å' scene=''> | + | <StructureSection load='4eu3' size='340' side='right'caption='[[4eu3]], [[Resolution|resolution]] 1.58Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[4eu3]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/"acetimonas_aceti"_(pasteur_1864)_orla-jensen_1909 "acetimonas aceti" (pasteur 1864) orla-jensen 1909]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4EU3 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4EU3 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[4eu3]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Acetobacter_aceti Acetobacter aceti]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4EU3 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4EU3 FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CIT:CITRIC+ACID'>CIT</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene></td></tr> | + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CIT:CITRIC+ACID'>CIT</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene></td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4eu4|4eu4]], [[4eu5|4eu5]], [[4eu6|4eu6]], [[4eu7|4eu7]], [[4eu8|4eu8]], [[4eu9|4eu9]], [[4eua|4eua]], [[4eub|4eub]], [[4euc|4euc]], [[4eud|4eud]]</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=4eu3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4eu3 OCA], [https://pdbe.org/4eu3 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4eu3 RCSB], [https://www.ebi.ac.uk/pdbsum/4eu3 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4eu3 ProSAT]</span></td></tr> |
| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">aarC ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=435 "Acetimonas aceti" (Pasteur 1864) Orla-Jensen 1909])</td></tr>
| + | |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Succinyl-CoA:acetate_CoA-transferase Succinyl-CoA:acetate CoA-transferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.8.3.18 2.8.3.18] </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=4eu3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4eu3 OCA], [http://pdbe.org/4eu3 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4eu3 RCSB], [http://www.ebi.ac.uk/pdbsum/4eu3 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4eu3 ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | + | == Function == |
| | + | [https://www.uniprot.org/uniprot/SCACT_ACEAC SCACT_ACEAC] Utilizes succinyl-CoA to convert toxic acetate to acetyl-CoA and succinate. Required for growth on acetic acid and for resistance to high levels of acetic acid. Has also low activity with acetoacetate as substrate.<ref>PMID:18502856</ref> <ref>PMID:23030530</ref> <ref>PMID:18502856</ref> [REFERENCE:3] |
| | <div style="background-color:#fffaf0;"> | | <div style="background-color:#fffaf0;"> |
| | == Publication Abstract from PubMed == | | == Publication Abstract from PubMed == |
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| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Succinyl-CoA:acetate CoA-transferase]] | + | [[Category: Acetobacter aceti]] |
| - | [[Category: Kappock, T J]] | + | [[Category: Large Structures]] |
| - | [[Category: Mullins, E A]] | + | [[Category: Kappock TJ]] |
| - | [[Category: Transferase]] | + | [[Category: Mullins EA]] |
| Structural highlights
Function
SCACT_ACEAC Utilizes succinyl-CoA to convert toxic acetate to acetyl-CoA and succinate. Required for growth on acetic acid and for resistance to high levels of acetic acid. Has also low activity with acetoacetate as substrate.[1] [2] [3] [REFERENCE:3]
Publication Abstract from PubMed
CoA-transferases catalyze transthioesterification reactions involving acyl-CoA substrates, using an active-site carboxylate to form covalent acyl anhydride and CoA-thioester adducts. Mechanistic studies of class I CoA-transferases suggested that acyl-CoA binding energy is used to accelerate rate-limiting acyl transfers by compressing the substrate thioester tightly against the catalytic glutamate [White, H., and Jencks, W. P. (1976) J. Biol. Chem. 251, 1688-1699]. The class I CoA-transferase succinyl-CoA:acetate CoA-transferase is an acetic acid resistance factor (AarC) with a role in a variant citric acid cycle in Acetobacter aceti. In an effort to identify residues involved in substrate recognition, x-ray crystal structures of a C-terminally His(6) tagged form (AarCH6) were determined for several wild-type and mutant complexes, including freeze-trapped acetylglutamyl anhydride and glutamyl-CoA thioester adducts. The latter shows the acetate product bound to an auxiliary site that is required for efficient carboxylate substrate recognition. A mutant in which the catalytic glutamate was changed to an alanine crystallized in a closed complex containing dethiaacetyl-CoA, which adopts an unusual curled conformation. A model of the acetyl-CoA Michaelis complex demonstrates the compression anticipated four decades ago by Jencks and reveals that the nucleophilic glutamate is held at a near-ideal angle for attack as the thioester oxygen is forced into an oxyanion hole composed of Gly388 NH and CoA N2. CoA is nearly immobile along its entire length during all stages of the enzyme reaction. Spatial and sequence conservation of key residues indicates that this mechanism is general among class I CoA-transferases.
Crystal structures of Acetobacter aceti succinyl-coenzyme A (CoA):acetate CoA-transferase (AarC) reveal specificity determinants and illustrate the mechanism used by class I CoA-transferases.,Mullins EA, Kappock TJ Biochemistry. 2012 Oct 2. PMID:23030530[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Mullins EA, Francois JA, Kappock TJ. A specialized citric acid cycle requiring succinyl-coenzyme A (CoA):acetate CoA-transferase (AarC) confers acetic acid resistance on the acidophile Acetobacter aceti. J Bacteriol. 2008 Jul;190(14):4933-40. Epub 2008 May 23. PMID:18502856 doi:10.1128/JB.00405-08
- ↑ Mullins EA, Kappock TJ. Crystal structures of Acetobacter aceti succinyl-coenzyme A (CoA):acetate CoA-transferase (AarC) reveal specificity determinants and illustrate the mechanism used by class I CoA-transferases. Biochemistry. 2012 Oct 2. PMID:23030530 doi:10.1021/bi300957f
- ↑ Mullins EA, Francois JA, Kappock TJ. A specialized citric acid cycle requiring succinyl-coenzyme A (CoA):acetate CoA-transferase (AarC) confers acetic acid resistance on the acidophile Acetobacter aceti. J Bacteriol. 2008 Jul;190(14):4933-40. Epub 2008 May 23. PMID:18502856 doi:10.1128/JB.00405-08
- ↑ Mullins EA, Kappock TJ. Crystal structures of Acetobacter aceti succinyl-coenzyme A (CoA):acetate CoA-transferase (AarC) reveal specificity determinants and illustrate the mechanism used by class I CoA-transferases. Biochemistry. 2012 Oct 2. PMID:23030530 doi:10.1021/bi300957f
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