Rhodoquinone biosynthesis in C.elegans requires precursors generated by the kynurenine pathway
- University of Toronto, Canada
Abstract
Parasitic helminths infect over a billion humans. To survive in the low oxygen environment of their hosts, these parasites use unusual anaerobic metabolism - this requires rhodoquinone (RQ), an electron carrier that is made by very few animal species. Crucially RQ is not made or used by any parasitic hosts and RQ synthesis is thus an ideal target for anthelmintics. However, little is known about how RQ is made and no drugs are known to block RQ synthesis. C.elegans makes RQ and can use RQ-dependent metabolic pathways - here, we use C.elegans genetics to show that tryptophan degradation via the kynurenine pathway is required to generate the key amine-containing precursors for RQ synthesis. We show that C.elegans requires RQ for survival in hypoxic conditions and, finally, we establish a high throughput assay for drugs that block RQ-dependent metabolism. This may drive the development of a new class of anthelmintic drugs. This study is a key first step in understanding how RQ is made in parasitic helminths.
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All data in manuscript and supporting files
Article and author information
Author details
Samantha Del Borrello
Funding
Canadian Institutes of Health Research (501584)
- Andrew G Fraser
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Del Borrello et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Rhodoquinone biosynthesis in C.elegans requires precursors generated by the kynurenine pathway
eLife 8:e48165.
https://doi.org/10.7554/eLife.48165
Further reading
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- Biochemistry and Chemical Biology
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In the bacterium M. smegmatis, an enzyme called MftG allows the the cofactor mycofactocin to transfers electrons released during ethanol metabolism to the electron transport chain.
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