Plasmodium falciparum LipB mutants display altered redox and carbon metabolism in asexual stages and cannot complete sporogony in Anopheles mosquitoes

Biddau, Marco and Kumar, T.R. Santha and Henrich, Philipp and Laine, Larissa M. and Blackburn, Gavin J. and Chokkathukalam, Achuthanunni and Li, Tao and Lee Sim, Kim and King, Lewis and Hoffman, Stephen L. and Barrett, Michael P. and Coombs, Graham H. and McFadden, Geoffrey I. and Fidock, David A. and Müller, Sylke and Sheiner, Lilach (2021) Plasmodium falciparum LipB mutants display altered redox and carbon metabolism in asexual stages and cannot complete sporogony in Anopheles mosquitoes. International Journal for Parasitology, 51 (6). pp. 441-453. ISSN 0020-7519

[thumbnail of Biddau-etal-IJP-2021-lasmodium-falciparum-LipB-mutants-display-altered-redox-and-carbon-metabolism]
Preview
Text (Biddau-etal-IJP-2021-lasmodium-falciparum-LipB-mutants-display-altered-redox-and-carbon-metabolism)
Biddau_etal_IJP_2021_lasmodium_falciparum_LipB_mutants_display_altered_redox_and_carbon_metabolism.pdf
Accepted Author Manuscript
License: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 logo

Download (2MB)| Preview

    Abstract

    Malaria is still one of the most important global infectious diseases. Emergence of drug resistance and a shortage of new efficient antimalarials continue to hamper a malaria eradication agenda. Malaria parasites are highly sensitive to changes in the redox environment. Understanding the mechanisms regulating parasite redox could contribute to the design of new drugs. Malaria parasites have a complex network of redox regulatory systems housed in their cytosol, in their mitochondrion and in their plastid (apicoplast). While the roles of enzymes of the thioredoxin and glutathione pathways in parasite survival have been explored, the antioxidant role of α-lipoic acid (LA) produced in the apicoplast has not been tested. To take a first step in teasing a putative role of LA in redox regulation, we analysed a mutant Plasmodium falciparum (3D7 strain) lacking the apicoplast lipoic acid protein ligase B (lipB) known to be depleted of LA. Our results showed a change in expression of redox regulators in the apicoplast and the cytosol. We further detected a change in parasite central carbon metabolism, with lipB deletion resulting in changes to glycolysis and tricarboxylic acid cycle activity. Further, in another Plasmodium cell line (NF54), deletion of lipB impacted development in the mosquito, preventing the detection of infectious sporozoite stages. While it is not clear at this point if the observed phenotypes are linked, these findings flag LA biosynthesis as an important subject for further study in the context of redox regulation in asexual stages, and point to LipB as a potential target for the development of new transmission drugs.