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Proton-Translocating Nicotinamide Nucleotide Transhydrogenase: A Structural Perspective
Qinghai Zhang1, Pius S Padayatti1, Josephine H Leung1
1Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, United States.
Frontiers in Physiology
|January 10, 2018
Summary
Nicotinamide nucleotide transhydrogenase (TH) produces NADPH using proton gradients, crucial for cellular redox balance and health. Structural studies reveal its complex mechanism, offering insights into aging and disease.
Area of Science:
- Biochemistry
- Structural Biology
- Mitochondrial Physiology
Background:
- Nicotinamide nucleotide transhydrogenase (TH) is a key mitochondrial enzyme.
- It couples proton gradients to NADPH production, vital for cellular redox homeostasis.
- Dysfunction is linked to aging and human diseases.
Purpose of the Study:
- To review structural findings on Nicotinamide nucleotide transhydrogenase (TH).
- To elucidate the complex domain coupling mechanism of TH.
- To discuss challenges in understanding TH's enzymatic function.
Main Methods:
- 3D crystallization of isolated soluble domains.
- Structural characterization of the transmembrane domain.
- Holo-enzyme structural determination from *Thermus thermophilus*.
Main Results:
- Detailed structural insights into TH's three-domain architecture.
- Conservation of domain architecture across species despite compositional differences.
- Recent structural data on the holo-enzyme and transmembrane domain.
Conclusions:
- Structural data provides a foundation for understanding TH mechanism.
- Further research is needed to fully elucidate the complex domain coupling.
- Understanding TH is critical for addressing aging and related diseases.
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