2B36: Crystal Structure Of Mycobacterium Tuberculosis Enoyl Reductase (inha) Inhibited By 5-pentyl-2-phenoxyphenol

Novel chemotherapeutics for treating multidrug-resistant (MDR) strains of Mycobacterium tuberculosis (MTB) are required to combat the spread of tuberculosis, a disease that kills more than 2 million people annually. Using structure-based drug design, we have developed a series of alkyl diphenyl ethers that are uncompetitive inhibitors of InhA, the enoyl reductase enzyme in the MTB fatty acid biosynthesis pathway. The most potent compound has a Ki' value of 1 nM for InhA and MIC99 values of 2-3 microg mL(-1) (6-10 microM) for both drug-sensitive and drug-resistant strains of MTB. Overexpression of InhA in MTB results in a 9-12-fold increase in MIC99, consistent with the belief that these compounds target InhA within the cell. In addition, transcriptional response studies reveal that the alkyl diphenyl ethers fail to upregulate a putative efflux pump and aromatic dioxygenase, detoxification mechanisms that are triggered by the lead compound triclosan. These diphenyl ether-based InhA inhibitors do not require activation by the mycobacterial KatG enzyme, thereby circumventing the normal mechanism of resistance to the front line drug isoniazid (INH) and thus accounting for their activity against INH-resistant strains of MTB.
PDB ID: 2B36Download
MMDB ID: 38017
PDB Deposition Date: 2005/9/19
Updated in MMDB: 2017/11
Experimental Method:
x-ray diffraction
Resolution: 2.8  Å
Source Organism:
Similar Structures:
Biological Unit for 2B36: tetrameric; determined by author
Molecular Components in 2B36
Label Count Molecule
Proteins (4 molecules)
Enoyl-[acyl-carrier-protein] Reductase [nadh]
Molecule annotation
Chemicals (8 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB