2gp6

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Current revision (09:29, 14 February 2024) (edit) (undo)
 
(15 intermediate revisions not shown.)
Line 1: Line 1:
-
[[Image:2gp6.gif|left|200px]]<br /><applet load="2gp6" size="350" color="white" frame="true" align="right" spinBox="true"
 
-
caption="2gp6, resolution 2.400&Aring;" />
 
-
'''X-ray crystal structure of Mycobacterium tuberculosis beta-ketoacyl acyl carrier protein synthase II (mtKasB)'''<br />
 
-
==Overview==
+
==X-ray crystal structure of Mycobacterium tuberculosis beta-ketoacyl acyl carrier protein synthase II (mtKasB)==
-
Mycolic acids are long chain alpha-alkyl branched, beta-hydroxy fatty acids that represent a characteristic component of the Mycobacterium tuberculosis cell wall. Through their covalent attachment to peptidoglycan via an arabinogalactan polysaccharide, they provide the basis for an essential outer envelope membrane. Mycobacteria possess two fatty acid synthases (FAS); FAS-I carries out de novo synthesis of fatty acids while FAS-II is considered to elongate medium chain length fatty acyl primers to provide long chain (C(56)) precursors of mycolic acids. Here we report the crystal structure of Mycobacterium tuberculosis beta-ketoacyl acyl carrier protein synthase (ACP) II mtKasB, a mycobacterial elongation condensing enzyme involved in FAS-II. This enzyme, along with the M. tuberculosis beta-ketoacyl ACP synthase I mtKasA, catalyzes the Claisen-type condensation reaction responsible for fatty acyl elongation in FAS-II and are potential targets for development of novel anti-tubercular drugs. The crystal structure refined to 2.4 A resolution revealed that, like other KAS-II enzymes, mtKasB adopts a thiolase fold but contains unique structural features in the capping region that may be crucial to its preference for longer fatty acyl chains than its counterparts from other bacteria. Modeling of mtKasA using the mtKasB structure as a template predicts the overall structures to be almost identical, but a larger entrance to the active site tunnel is envisaged that might contribute to the greater sensitivity of mtKasA to the inhibitor thiolactomycin (TLM). Modeling of TLM binding in mtKasB shows that the drug fits the active site poorly and results of enzyme inhibition assays using TLM analogues are wholly consistent with our structural observations. Consequently, the structure described here further highlights the potential of TLM as an anti-tubercular lead compound and will aid further exploration of the TLM scaffold towards the design of novel compounds, which inhibit mycobacterial KAS enzymes more effectively.
+
<StructureSection load='2gp6' size='340' side='right'caption='[[2gp6]], [[Resolution|resolution]] 2.40&Aring;' scene=''>
 +
== Structural highlights ==
 +
<table><tr><td colspan='2'>[[2gp6]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Mycobacterium_tuberculosis Mycobacterium tuberculosis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2GP6 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2GP6 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]] 2.4&#8491;</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=2gp6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2gp6 OCA], [https://pdbe.org/2gp6 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2gp6 RCSB], [https://www.ebi.ac.uk/pdbsum/2gp6 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2gp6 ProSAT], [https://www.topsan.org/Proteins/TBSGC/2gp6 TOPSAN]</span></td></tr>
 +
</table>
 +
== Function ==
 +
[https://www.uniprot.org/uniprot/KASB_MYCTU KASB_MYCTU] Part of the mycobacterial fatty acid elongation system FAS-II, which is involved in mycolic acid biosynthesis. Catalyzes the elongation of long chain acyl-ACP substrates by the addition of two carbons from malonyl-ACP to an acyl acceptor (PubMed:11600501, PubMed:12464486, PubMed:16873379). Involved in extension of the mycolate chains to full lengths and produces longer chain multiunsaturated hydrocarbons averaging 54 carbons in length (PubMed:12464486). Essential for resistance to macrophage antimicrobial activity (PubMed:12950920).<ref>PMID:11600501</ref> <ref>PMID:12464486</ref> <ref>PMID:12950920</ref> <ref>PMID:16873379</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/gp/2gp6_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=2gp6 ConSurf].
 +
<div style="clear:both"></div>
-
==About this Structure==
+
==See Also==
-
2GP6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mycobacterium_tuberculosis Mycobacterium tuberculosis]. Active as [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] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2GP6 OCA].
+
*[[Acyl carrier protein synthase 3D structures|Acyl carrier protein synthase 3D structures]]
-
 
+
== References ==
-
==Reference==
+
<references/>
-
X-ray crystal structure of Mycobacterium tuberculosis beta-ketoacyl acyl carrier protein synthase II (mtKasB)., Sridharan S, Wang L, Brown AK, Dover LG, Kremer L, Besra GS, Sacchettini JC, J Mol Biol. 2007 Feb 16;366(2):469-80. Epub 2006 Nov 7. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17174327 17174327]
+
__TOC__
-
[[Category: Beta-ketoacyl-acyl-carrier-protein synthase I]]
+
</StructureSection>
 +
[[Category: Large Structures]]
[[Category: Mycobacterium tuberculosis]]
[[Category: Mycobacterium tuberculosis]]
-
[[Category: Single protein]]
+
[[Category: Sacchettini J]]
-
[[Category: Sacchettini, J.]]
+
[[Category: Sridharan S]]
-
[[Category: Sridharan, S.]]
+
-
[[Category: TBSGC, TB Structural Genomics Consortium.]]
+
-
[[Category: protein structure initiative]]
+
-
[[Category: psi]]
+
-
[[Category: structural genomics]]
+
-
[[Category: tb structural genomics consortium]]
+
-
[[Category: tbsgc]]
+
-
[[Category: thiolase fold]]
+
-
 
+
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:33:53 2008''
+

Current revision

X-ray crystal structure of Mycobacterium tuberculosis beta-ketoacyl acyl carrier protein synthase II (mtKasB)

PDB ID 2gp6

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools