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6co9
From Proteopedia
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| - | '''Unreleased structure''' | ||
| - | + | ==Crystal structure of Rhodococcus jostii RHA1 IpdAB COCHEA-COA complex== | |
| + | <StructureSection load='6co9' size='340' side='right'caption='[[6co9]], [[Resolution|resolution]] 1.60Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[6co9]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Rhodococcus_jostii_RHA1 Rhodococcus jostii RHA1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6CO9 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6CO9 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]] 1.602Å</td></tr> | ||
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=F8G:S-{(3R,5R,9R)-1-[(2R,3S,4R,5R)-5-(6-amino-9H-purin-9-yl)-4-hydroxy-3-(phosphonooxy)tetrahydrofuran-2-yl]-3,5,9-trihydroxy-8,8-dimethyl-3,5-dioxido-10,14-dioxo-2,4,6-trioxa-11,15-diaza-3lambda~5~,5lambda~5~-diphosphaheptadecan-17-yl}+(5R,10R)-7-hydroxy-10-methyl-2-oxo-1-oxaspiro[4.5]dec-6-ene-6-carbothioate+(non-preferred+name)'>F8G</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=6co9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6co9 OCA], [https://pdbe.org/6co9 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6co9 RCSB], [https://www.ebi.ac.uk/pdbsum/6co9 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6co9 ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/IPDA_RHOJR IPDA_RHOJR] Involved in the final steps of cholesterol and steroid degradation (PubMed:28377529, PubMed:29581275). Opens the last steroid ring of cholesterol by catalyzing the hydrolysis of (3E)-2-(2-carboxylatoethyl)-3-methyl-6-oxocyclohex-1-ene-1-carboxyl-CoA (COCHEA-CoA) to 6-methyl-3,7-dioxodecanedioyl-CoA (MeDODA-CoA) (Probable) (PubMed:29581275).<ref>PMID:28377529</ref> <ref>PMID:29581275</ref> <ref>PMID:28377529</ref> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | Mycobacterium tuberculosis (Mtb) grows on host-derived cholesterol during infection. IpdAB, found in all steroid-degrading bacteria and a determinant of pathogenicity, has been implicated in the hydrolysis of the last steroid ring. Phylogenetic analyses revealed that IpdAB orthologs form a clade of CoA transferases (CoTs). In a coupled assay with a thiolase, IpdAB transformed the cholesterol catabolite (R)-2-(2-carboxyethyl)-3-methyl-6-oxocyclohex-1-ene-1-carboxyl-CoA (COCHEA-CoA) and CoASH to 4-methyl-5-oxo-octanedioyl-CoA (MOODA-CoA) and acetyl-CoA with high specificity (kcat/Km = 5.8 +/- 0.8 x 10(4) M(-1)s(-1)). The structure of MOODA-CoA was consistent with IpdAB hydrolyzing COCHEA-CoA to a beta-keto-thioester, a thiolase substrate. Contrary to characterized CoTs, IpdAB exhibited no activity toward small CoA thioesters. Further, IpdAB lacks the catalytic glutamate residue that is conserved in the beta-subunit of characterized CoTs and a glutamyl-CoA intermediate was not trapped during turnover. By contrast, Glu105(A), conserved in the alpha-subunit of IpdAB, was essential for catalysis. A crystal structure of the IpdAB.COCHEA-CoA complex, solved to 1.4 A, revealed that Glu105(A) is positioned to act as a catalytic base. Upon titration with COCHEA-CoA, the E105A(A) variant accumulated a yellow-colored species (lambdamax = 310 nm; Kd = 0.4 +/- 0.2 muM) typical of beta-keto enolates. In the presence of D2O, IpdAB catalyzed the deuteration of COCHEA-CoA adjacent to the hydroxylation site at rates consistent with kcat Based on these data and additional IpdAB variants, we propose a retro-Claisen condensation-like mechanism for the IpdAB-mediated hydrolysis of COCHEA-CoA. This study expands the range of known reactions catalyzed by the CoT superfamily and provides mechanistic insight into an important determinant of Mtb pathogenesis. | ||
| - | + | IpdAB, a virulence factor in Mycobacterium tuberculosis, is a cholesterol ring-cleaving hydrolase.,Crowe AM, Workman SD, Watanabe N, Worrall LJ, Strynadka NCJ, Eltis LD Proc Natl Acad Sci U S A. 2018 Mar 26. pii: 1717015115. doi:, 10.1073/pnas.1717015115. PMID:29581275<ref>PMID:29581275</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | [[Category: | + | </div> |
| - | [[Category: | + | <div class="pdbe-citations 6co9" style="background-color:#fffaf0;"></div> |
| - | [[Category: | + | == References == |
| - | [[Category: | + | <references/> |
| - | [[Category: | + | __TOC__ |
| - | [[Category: | + | </StructureSection> |
| - | [[Category: | + | [[Category: Large Structures]] |
| + | [[Category: Rhodococcus jostii RHA1]] | ||
| + | [[Category: Crowe AM]] | ||
| + | [[Category: Eltis LD]] | ||
| + | [[Category: Strynadka NCJ]] | ||
| + | [[Category: Watanabe N]] | ||
| + | [[Category: Workman SD]] | ||
| + | [[Category: Worrall LJ]] | ||
Current revision
Crystal structure of Rhodococcus jostii RHA1 IpdAB COCHEA-COA complex
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