1bvr
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M.TB. ENOYL-ACP REDUCTASE (INHA) IN COMPLEX WITH NAD+ AND C16-FATTY-ACYL-SUBSTRATE
OverviewOverview
Enoyl-ACP reductases participate in fatty acid biosynthesis by utilizing, NADH to reduce the trans double bond between positions C2 and C3 of a, fatty acyl chain linked to the acyl carrier protein. The enoyl-ACP, reductase from Mycobacterium tuberculosis, known as InhA, is a member of, an unusual FAS-II system that prefers longer chain fatty acyl substrates, for the purpose of synthesizing mycolic acids, a major component of, mycobacterial cell walls. The crystal structure of InhA in complex with, NAD+ and a C16 fatty acyl substrate, trans-2-hexadecenoyl-(N-acetylcysteamine)-thioester, reveals that the, substrate binds in a general "U-shaped" conformation, with the trans, double bond positioned directly adjacent to the nicotinamide ring of NAD+., The side chain of Tyr158 directly interacts with the thioester carbonyl, oxygen of the C16 fatty acyl substrate and therefore could help stabilize, the enolate intermediate, proposed to form during substrate catalysis., Hydrophobic residues, primarily from the substrate binding loop (residues, 196-219), engulf the fatty acyl chain portion of the substrate. The, substrate binding loop of InhA is longer than that of other enoyl-ACP, reductases and creates a deeper substrate binding crevice, consistent with, the ability of InhA to recognize longer chain fatty acyl substrates.
About this StructureAbout this Structure
1BVR is a Single protein structure of sequence from Mycobacterium tuberculosis with NAD and THT as ligands. Active as [acyl-carrier-protein_reductase_(NADH) Enoyl-[acyl-carrier-protein] reductase (NADH)], with EC number 1.3.1.9 Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of the Mycobacterium tuberculosis enoyl-ACP reductase, InhA, in complex with NAD+ and a C16 fatty acyl substrate., Rozwarski DA, Vilcheze C, Sugantino M, Bittman R, Sacchettini JC, J Biol Chem. 1999 May 28;274(22):15582-9. PMID:10336454 [[Category: Enoyl-[acyl-carrier-protein] reductase (NADH)]]
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