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| | ==X-ray crystal structure of R46A,R161A mutant of Mycobacterium tuberculosis FabH== | | ==X-ray crystal structure of R46A,R161A mutant of Mycobacterium tuberculosis FabH== |
| - | <StructureSection load='2ahb' size='340' side='right' caption='[[2ahb]], [[Resolution|resolution]] 2.00Å' scene=''> | + | <StructureSection load='2ahb' size='340' side='right'caption='[[2ahb]], [[Resolution|resolution]] 2.00Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[2ahb]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_tuberculosis"_(zopf_1883)_klein_1884 "bacillus tuberculosis" (zopf 1883) klein 1884]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AHB OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2AHB FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[2ahb]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/"bacillus_tuberculosis"_(zopf_1883)_klein_1884 "bacillus tuberculosis" (zopf 1883) klein 1884]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AHB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2AHB FirstGlance]. <br> |
| - | </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1m1m|1m1m]], [[1hzp|1hzp]]</td></tr> | + | </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[1m1m|1m1m]], [[1hzp|1hzp]]</div></td></tr> |
| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">fabH ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1773 "Bacillus tuberculosis" (Zopf 1883) Klein 1884])</td></tr> | + | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">fabH ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1773 "Bacillus tuberculosis" (Zopf 1883) Klein 1884])</td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Beta-ketoacyl-[acyl-carrier-protein]_synthase_I Beta-ketoacyl-[acyl-carrier-protein] synthase I], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.3.1.41 2.3.1.41] </span></td></tr> | + | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Beta-ketoacyl-[acyl-carrier-protein]_synthase_I Beta-ketoacyl-[acyl-carrier-protein] synthase I], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.3.1.41 2.3.1.41] </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=2ahb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ahb OCA], [http://pdbe.org/2ahb PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2ahb RCSB], [http://www.ebi.ac.uk/pdbsum/2ahb PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=2ahb ProSAT]</span></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=2ahb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ahb OCA], [https://pdbe.org/2ahb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2ahb RCSB], [https://www.ebi.ac.uk/pdbsum/2ahb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2ahb ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/FABH_MYCTU FABH_MYCTU]] Catalyzes the condensation reaction of fatty acid synthesis by the addition to an acyl acceptor of two carbons from malonyl-ACP. Catalyzes the first condensation reaction which initiates fatty acid synthesis and may therefore play a role in governing the total rate of fatty acid production. Possesses both acetoacetyl-ACP synthase and acetyl transacylase activities. Has some substrate specificity for long chain acyl-CoA such as myristoyl-CoA. Does not use acyl-CoA as primer. Its substrate specificity determines the biosynthesis of mycolic acid fatty acid chain, which is characteristic of mycobacterial cell wall.<ref>PMID:10840036</ref> | + | [[https://www.uniprot.org/uniprot/FABH_MYCTU FABH_MYCTU]] Catalyzes the condensation reaction of fatty acid synthesis by the addition to an acyl acceptor of two carbons from malonyl-ACP. Catalyzes the first condensation reaction which initiates fatty acid synthesis and may therefore play a role in governing the total rate of fatty acid production. Possesses both acetoacetyl-ACP synthase and acetyl transacylase activities. Has some substrate specificity for long chain acyl-CoA such as myristoyl-CoA. Does not use acyl-CoA as primer. Its substrate specificity determines the biosynthesis of mycolic acid fatty acid chain, which is characteristic of mycobacterial cell wall.<ref>PMID:10840036</ref> |
| | == Evolutionary Conservation == | | == Evolutionary Conservation == |
| | [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
| | Check<jmol> | | Check<jmol> |
| | <jmolCheckbox> | | <jmolCheckbox> |
| - | <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ah/2ahb_consurf.spt"</scriptWhenChecked> | + | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ah/2ahb_consurf.spt"</scriptWhenChecked> |
| | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> |
| | <text>to colour the structure by Evolutionary Conservation</text> | | <text>to colour the structure by Evolutionary Conservation</text> |
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| | </div> | | </div> |
| | <div class="pdbe-citations 2ahb" style="background-color:#fffaf0;"></div> | | <div class="pdbe-citations 2ahb" style="background-color:#fffaf0;"></div> |
| | + | |
| | + | ==See Also== |
| | + | *[[Acyl carrier protein synthase 3D structures|Acyl carrier protein synthase 3D structures]] |
| | == References == | | == References == |
| | <references/> | | <references/> |
| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| | + | [[Category: Large Structures]] |
| | [[Category: Besra, G S]] | | [[Category: Besra, G S]] |
| | [[Category: Brown, A K]] | | [[Category: Brown, A K]] |
| Structural highlights
Function
[FABH_MYCTU] Catalyzes the condensation reaction of fatty acid synthesis by the addition to an acyl acceptor of two carbons from malonyl-ACP. Catalyzes the first condensation reaction which initiates fatty acid synthesis and may therefore play a role in governing the total rate of fatty acid production. Possesses both acetoacetyl-ACP synthase and acetyl transacylase activities. Has some substrate specificity for long chain acyl-CoA such as myristoyl-CoA. Does not use acyl-CoA as primer. Its substrate specificity determines the biosynthesis of mycolic acid fatty acid chain, which is characteristic of mycobacterial cell wall.[1]
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 PubMed
Mycolic acids are the dominant feature of the Mycobacterium tuberculosis cell wall. These alpha-alkyl, beta-hydroxy fatty acids are formed by the condensation of two fatty acids, a long meromycolic acid and a shorter C(24)-C(26) fatty acid. The component fatty acids are produced via a combination of type I and II fatty acid synthases (FAS) with FAS-I products being elongated by FAS-II toward meromycolic acids. The beta-ketoacyl-acyl carrier protein (ACP) synthase III encoded by mtfabH (mtFabH) links FAS-I and FAS-II, catalyzing the condensation of FAS-I-derived acyl-CoAs with malonyl-acyl carrier protein (ACP). The acyl-CoA chain length specificity of mtFabH was assessed in vitro; the enzyme extended longer, physiologically relevant acyl-CoA primers when paired with AcpM, its natural partner, than with Escherichia coli ACP. The ability of the enzyme to use E. coli ACP suggests that a similar mode of binding is likely with both ACPs, yet it is clear that unique factors inherent to AcpM modulate the substrate specificity of mtFabH. Mutation of proposed key mtFabH residues was used to define their catalytic roles. Substitution of supposed acyl-CoA binding residues reduced transacylation, with double substitutions totally abrogating activity. Mutation of Arg(46) revealed its more critical role in malonyl-AcpM decarboxylation than in the acyl-CoA binding role. Interestingly, this effect was suppressed intragenically by Arg(161) --> Ala substitution. Our structural studies suggested that His(258), previously implicated in malonyl-ACP decarboxylation, also acts as an anchor point for a network of water molecules that we propose promotes deprotonation and transacylation of Cys(122).
Probing the mechanism of the Mycobacterium tuberculosis beta-ketoacyl-acyl carrier protein synthase III mtFabH: factors influencing catalysis and substrate specificity.,Brown AK, Sridharan S, Kremer L, Lindenberg S, Dover LG, Sacchettini JC, Besra GS J Biol Chem. 2005 Sep 16;280(37):32539-47. Epub 2005 Jul 22. PMID:16040614[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Choi KH, Kremer L, Besra GS, Rock CO. Identification and substrate specificity of beta -ketoacyl (acyl carrier protein) synthase III (mtFabH) from Mycobacterium tuberculosis. J Biol Chem. 2000 Sep 8;275(36):28201-7. PMID:10840036 doi:http://dx.doi.org/10.1074/jbc.M003241200
- ↑ Brown AK, Sridharan S, Kremer L, Lindenberg S, Dover LG, Sacchettini JC, Besra GS. Probing the mechanism of the Mycobacterium tuberculosis beta-ketoacyl-acyl carrier protein synthase III mtFabH: factors influencing catalysis and substrate specificity. J Biol Chem. 2005 Sep 16;280(37):32539-47. Epub 2005 Jul 22. PMID:16040614 doi:10.1074/jbc.M413216200
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