Apicoplast lipoic acid protein ligase B is not essential for Plasmodium falciparum
Abstract
Lipoic acid (LA) is an essential cofactor of alpha-keto acid dehydrogenase complexes (KADHs) and the glycine cleavage system. In Plasmodium, LA is attached to the KADHs by organelle-specific lipoylation pathways. Biosynthesis of LA exclusively occurs in the apicoplast, comprising octanoyl-[acyl carrier protein]: protein N-octanoyltransferase (LipB) and LA synthase. Salvage of LA is mitochondrial and scavenged LA is ligated to the KADHs by LA protein ligase 1 (LplA1). Both pathways are entirely independent, suggesting that both are likely to be essential for parasite survival. However, disruption of the LipB gene did not negatively affect parasite growth despite a drastic loss of LA (> 90%). Surprisingly, the sole, apicoplast-located pyruvate dehydrogenase still showed lipoylation, suggesting that an alternative lipoylation pathway exists in this organelle. We provide evidence that this residual lipoylation is attributable to the dual targeted, functional lipoate protein ligase 2 (LplA2). Localisation studies show that LplA2 is present in both mitochondrion and apicoplast suggesting redundancy between the lipoic acid protein ligases in the erythrocytic stages of P. falciparum.
Citation
Guenther , S , Wallace , L , Patzewitz , E-M , McMillan , P J , Storm , J , Wrenger , C , Bissett , R , Smith , T K & Mueller , S 2007 , ' Apicoplast lipoic acid protein ligase B is not essential for Plasmodium falciparum ' , PLoS Pathogens , vol. 3 , no. 12 , e189 , pp. 1938-1949 . https://doi.org/10.1371/journal.ppat.0030189
Publication
PLoS Pathogens
Status
Peer reviewed
ISSN
1553-7366Type
Journal article
Rights
© 2007 Günther et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.