Disruption of key NADH-binding pocket residues of the Mycobacterium tuberculosis InhA affects DD-CoA binding ability

Daniel J Shaw, Kirsty Robb, Beatrice V Vetter, Madeline Tong, Virginie Molle, Neil T Hunt, Paul A Hoskisson

Research output: Contribution to journalArticlepeer-review


Tuberculosis (TB) is a global health problem that affects over 10 million people. There is an urgent need to develop novel antimicrobial therapies to combat TB. To achieve this, a thorough understanding of key validated drug targets is required. The enoyl reductase InhA, responsible for synthesis of essential mycolic acids in the mycobacterial cell wall, is the target for the frontline anti-TB drug isoniazid. To better understand the activity of this protein a series of mutants, targeted to the NADH co-factor binding pocket were created. Residues P193 and W222 comprise a series of hydrophobic residues surrounding the cofactor binding site and mutation of both residues negatively affect InhA function. Construction of an M155A mutant of InhA results in increased affinity for NADH and DD-CoA turnover but with a reduction in Vmax for DD-CoA, impairing overall activity. This suggests that NADH-binding geometry of InhA likely permits long-range interactions between residues in the NADH-binding pocket to facilitate substrate turnover in the DD-CoA binding region of the protein. Understanding the precise details of substrate binding and turnover in InhA and how this may affect protein-protein interactions may facilitate the development of improved inhibitors enabling the development of novel anti-TB drugs.

Original languageEnglish
Article number4714
Pages (from-to)4714
JournalScientific Reports
Issue number1
Publication statusPublished - 1 Dec 2017

Bibliographical note

© The Author(s) 2017


  • Acyl Coenzyme A/metabolism
  • Bacterial Proteins/chemistry
  • Binding Sites
  • Catalytic Domain
  • Hydrophobic and Hydrophilic Interactions
  • Kinetics
  • Mutagenesis, Site-Directed
  • Mycobacterium tuberculosis/genetics
  • NAD/genetics
  • Oxidoreductases/chemistry
  • Protein Binding

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