2gp6
From Proteopedia
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|GENE= kasB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1773 Mycobacterium tuberculosis]) | |GENE= kasB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1773 Mycobacterium tuberculosis]) | ||
|DOMAIN=<span class='plainlinks'>[http://www.ncbi.nlm.nih.gov/Structure/cdd/cddsrv.cgi?uid=PRK07910 PRK07910], [http://www.ncbi.nlm.nih.gov/Structure/cdd/cddsrv.cgi?uid=cd00834 KAS_I_II]</span> | |DOMAIN=<span class='plainlinks'>[http://www.ncbi.nlm.nih.gov/Structure/cdd/cddsrv.cgi?uid=PRK07910 PRK07910], [http://www.ncbi.nlm.nih.gov/Structure/cdd/cddsrv.cgi?uid=cd00834 KAS_I_II]</span> | ||
| - | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2gp6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2gp6 OCA], [http://www.ebi.ac.uk/pdbsum/2gp6 PDBsum | + | |RELATEDENTRY=[[1kas|1KAS]], [[1j3n|1J3N]], [[1e5m|1E5M]] |
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2gp6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2gp6 OCA], [http://www.ebi.ac.uk/pdbsum/2gp6 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=2gp6 RCSB]</span> | ||
}} | }} | ||
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[[Category: thiolase fold]] | [[Category: thiolase fold]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 03:19:37 2008'' |
Revision as of 00:19, 31 March 2008
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| , resolution 2.400Å | |||||||
|---|---|---|---|---|---|---|---|
| Gene: | kasB (Mycobacterium tuberculosis) | ||||||
| Activity: | Beta-ketoacyl-acyl-carrier-protein synthase I, with EC number 2.3.1.41 | ||||||
| Domains: | PRK07910, KAS_I_II | ||||||
| Related: | 1KAS, 1J3N, 1E5M
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
X-ray crystal structure of Mycobacterium tuberculosis beta-ketoacyl acyl carrier protein synthase II (mtKasB)
Overview
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.
About this Structure
2GP6 is a Single protein structure of sequence from Mycobacterium tuberculosis. Full crystallographic information is available from OCA.
Reference
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:17174327
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