2qx1
From Proteopedia
| |||||||
| , resolution 2.60Å | |||||||
|---|---|---|---|---|---|---|---|
| Sites: | , and | ||||||
| Ligands: | , | ||||||
| Gene: | fabH (Mycobacterium tuberculosis) | ||||||
| Activity: | Beta-ketoacyl-acyl-carrier-protein synthase I, with EC number 2.3.1.41 | ||||||
| Related: | 1U6S, 1HZP, 1U6E, 1HNJ, 1HNK
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of the complex between mycobacterium tuberculosis beta-ketoacyl-acyl carrier protein synthase III (FABH) and decyl-COA disulfide
Overview
The dimeric Mycobacterium tuberculosis FabH (mtFabH) catalyses a Claisen-type condensation between an acyl-CoA and malonyl-acyl carrier protein (ACP) to initiate the Type II fatty acid synthase cycle. To analyze the initial covalent acylation of mtFabH with acyl-CoA, we challenged it with mixture of C(6)-C(20) acyl-CoAs and the ESI-MS analysis showed reaction at both subunits and a strict specificity for C(12) acyl CoA. Crystallographic and ESI-MS studies of mtFabH with a decyl-CoA disulfide inhibitor revealed a decyl chain bound in acyl-binding channels of both subunits through disulfide linkage to the active site cysteine. These data provide the first unequivocal evidence that both subunits of mtFabH can react with substrates or inhibitor. The discrepancy between the observed C(12) acyl-CoA substrate specificity in the initial acylation step and the higher catalytic efficiency of mtFabH for C(18)-C(20) acyl-CoA substrates in the overall mtFabH catalyzed reaction suggests a role for M. tuberculosis ACP as a specificity determinant in this reaction.
About this Structure
2QX1 is a Single protein structure of sequence from Mycobacterium tuberculosis. Full crystallographic information is available from OCA.
Reference
Probing reactivity and substrate specificity of both subunits of the dimeric Mycobacterium tuberculosis FabH using alkyl-CoA disulfide inhibitors and acyl-CoA substrates., Sachdeva S, Musayev F, Alhamadsheh MM, Neel Scarsdale J, Tonie Wright H, Reynolds KA, Bioorg Chem. 2008 Apr;36(2):85-90. Epub 2007 Dec 21. PMID:18096200
Page seeded by OCA on Mon Mar 31 04:54:21 2008
Categories: Beta-ketoacyl-acyl-carrier-protein synthase I | Mycobacterium tuberculosis | Single protein | Alhamadsheh, M. | Musayev, F. | Reynolds, K A. | Sachdeva, S. | Scarsdale, J N. | Wright, H T. | Acyltransferase | Cytoplasm | Enzyme inhibitor complex | Fatty acid biosynthesis | Lipid synthesis | Mechanism based inhibitor | Multifunctional enzyme | Myobacterium tuberculosis | Structural basis for substrate specificity | Transferase
