PDBsum entry 2ieb

Oxidoreductase

PDB id: 2ieb

Contents

Protein chain

268 a.a. *

Ligands

ZID

Waters ×212

* Residue conservation analysis

PDB id:

2ieb

Name:

Oxidoreductase

Title:

Crystal structure of isoniazid-resistant s94a enoyl-acp(coa) reductase mutant enzyme from mycobacterium tuberculosis in complex with nadh- inh

Structure:

Enoyl-[acyl-carrier-protein] reductase [nadh]. Chain: a. Synonym: nadh-dependent enoyl-acp reductase. Engineered: yes. Mutation: yes

Source:

Mycobacterium tuberculosis. Organism_taxid: 1773. Gene: inha. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

Resolution:

2.20Å R-factor: 0.187 R-free: 0.240

Authors:

M.V.B.Dias,A.M.X.Prado,I.B.Vasconcelos,V.Fadel,L.A.Basso,D.S.Santos, W.F.Azevedo Jr.

Key ref:

M.V.Dias et al. (2007). Crystallographic studies on the binding of isonicotinyl-NAD adduct to wild-type and isoniazid resistant 2-trans-enoyl-ACP (CoA) reductase from Mycobacterium tuberculosis. J Struct Biol, 159, 369-380. PubMed id: 17588773

Date:

18-Sep-06 Release date: 24-Jul-07

Protein chain

P9WGR1  (INHA_MYCTU) -  Enoyl-[acyl-carrier-protein] reductase [NADH] from Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv)

Seq: 269 a.a.

Struc: 268 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.1.3.1.9 - enoyl-[acyl-carrier-protein] reductase (NADH).
• Reaction: a 2,3-saturated acyl-[ACP] + NAD⁺ = a (2E)-enoyl-[ACP] + NADH + H⁺

2,3-saturated acyl-[ACP] + NAD(+) (Bound ligand (Het Group name = ZID) matches with 84.62% similarity) = (2E)-enoyl-[ACP] + NADH + H(+)

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

Added reference

J Struct Biol 159:369-380 (2007)

PubMed id: 17588773

Crystallographic studies on the binding of isonicotinyl-NAD adduct to wild-type and isoniazid resistant 2-trans-enoyl-ACP (CoA) reductase from Mycobacterium tuberculosis.

M.V.Dias, I.B.Vasconcelos, A.M.Prado, V.Fadel, L.A.Basso, W.F.de Azevedo, D.S.Santos.

ABSTRACT

The resumption of tuberculosis led to an increased need to understand the molecular mechanisms of drug action and drug resistance, which should provide significant insight into the development of newer compounds. Isoniazid (INH), the most prescribed drug to treat TB, inhibits an NADH-dependent enoyl-acyl carrier protein reductase (InhA) that provides precursors of mycolic acids, which are components of the mycobacterial cell wall. InhA is the major target of the mode of action of isoniazid. INH is a pro-drug that needs activation to form the inhibitory INH-NAD adduct. Missense mutations in the inhA structural gene have been identified in clinical isolates of Mycobacterium tuberculosis resistant to INH. To understand the mechanism of resistance to INH, we have solved the structure of two InhA mutants (I21V and S94A), identified in INH-resistant clinical isolates, and compare them to INH-sensitive WT InhA structure in complex with the INH-NAD adduct. We also solved the structure of unliganded INH-resistant S94A protein, which is the first report on apo form of InhA. The salient features of these structures are discussed and should provide structural information to improve our understanding of the mechanism of action of, and resistance to, INH in M. tuberculosis. The unliganded structure of InhA allows identification of conformational changes upon ligand binding and should help structure-based drug design of more potent antimycobacterial agents.