The NMR solution structure of Mycobacterium tuberculosis F‐ATP synthase subunit ε provides new insight into energy coupling inside the rotary engine
Abstract
Mycobacterium tuberculosis (Mt) F1F0 ATP synthase (α3:β3:γ:δ:ε:a:b:b′:c9) is essential for the viability of growing and nongrowing persister cells of the pathogen. Here, we present the first NMR solution structure of Mtε, revealing an N‐terminal β‐barrel domain (NTD) and a C‐terminal domain (CTD) composed of a helix‐loop‐helix with helix 1 and ‐2 being shorter compared to their counterparts in other bacteria. The C‐terminal amino acids are oriented toward the NTD, forming a domain‐domain interface between the NTD and CTD. The Mtε structure provides a novel mechanistic model of coupling c‐ring‐ and ε rotation via a patch of hydrophobic residues in the NTD and residues of the CTD to the bottom of the catalytic α3β3‐headpiece. To test our model, genome site‐directed mutagenesis was employed to introduce amino acid changes in these two parts of the epsilon subunit. Inverted vesicle assays show that these mutations caused an increase in ATP hydrolysis activity and a reduction in ATP synthesis. The structural and enzymatic data are discussed in light of the transition mechanism of a compact and extended state of Mtε, which provides the inhibitory effects of this coupling subunit inside the rotary engine. Finally, the employment of these data with molecular docking shed light into the second binding site of the drug Bedaquiline.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 06, 2018
- Source ID
- 10.1111/febs.14392
Entities
People
- Gerhard Grüber
- Lavanya Sundararaman
- Malathy S. S. Manimekalai
- Nebojša Bogdanović
- Priya Ragunathan
- Shin Joon
- Subhashri Kundu
- Thomas Dick
- Wilson Nartey
Organizations
- Ministry of Health
- Nanyang Technological University
- National Research Foundation
- National University of Singapore
- Naval Medical Research Center
- Neurosciences Research Foundation
- Nottingham Trent University
- Rutgers University