Cytidine diphosphate diacylglycerol synthase (CDS) diverts phosphatidic acid towards the biosynthesis of CDP-DAG, an obligatory liponucleotide intermediate in anionic phospholipid biosynthesis. The 78kDa predicted Plasmodium falciparum CDS (PfCDS) is recovered as a 50 kDa conserved C-terminal cytidylyltransferase domain (C-PfCDS) and a 28kDa fragment that corresponds to the unusually long hydrophilic asparagine-rich N-terminal extension (N-PfCDS). Here, we show that the two fragments of PfCDS are the processed forms of the 78 kDa pro-form that is encoded from a single transcript with no alternate translation start site for C-PfCDS. PfCDS, which shares 54% sequence identity with Plasmodium knowlesi CDS (PkCDS), could substitute for PkCDS in P. knowlesi. Experiments to disrupt either the full-length or the N-terminal extension of PkCDS indicate that not only the C-terminal cytidylyltransferase domain but also the N-terminal extension is essential to Plasmodium spp. PkCDS and PfCDS introduced in P. knowlesi were processed in the parasite, suggesting a conserved parasite-dependent mechanism. The N-PfCDS appears to be a peripheral membrane protein and is trafficked outside the parasite to the parasitophorous vacuole. Although the function of this unusual N-PfCDS remains enigmatic, the study here highlights features of this essential gene and its biological importance during the intra-erythrocytic cycle of the parasite.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.ijpara.2010.03.006 | DOI Listing |
Commun Biol
January 2025
Faculty of Science, Ibaraki University, Mito, Japan.
Halorhodospira (Hlr.) halophila strain BN9622 is an extremely halophilic and alkaliphilic purple phototrophic bacterium and has been widely used as a model for exploring the osmoadaptive and photosynthetic strategies employed by phototrophic extreme halophiles that enable them to thrive in hypersaline environments. Here we present the cryo-EM structures of (1) a unique native Hlr.
View Article and Find Full Text PDFUnlabelled: Bactofilins are a recently discovered class of cytoskeletal protein, widely implicated in subcellular organization and morphogenesis in bacteria and archaea. Several lines of evidence suggest that bactofilins polymerize into filaments using a central β-helical core domain, flanked by variable N- and C-terminal domains that may be important for scaffolding and other functions. However, a systematic exploration of the characteristics of these domains has yet to be performed.
View Article and Find Full Text PDFJ Biol Chem
December 2024
Department of Molecular Biology and Biophysics, UCONN Health, Farmington, CT 06032, USA. Electronic address:
Biochem Biophys Res Commun
January 2025
Center of Protein Studies, Faculty of Biology, Havana University, Havana, Cuba.
Sticholysin I and II (St I/II) belong to the actinoporins family; these proteins form pores in host cell membranes by binding their N-terminal segment to the membrane, leading to protein-lipid (toroidal) pores. Peptides derived from actinoporins pore-forming domains replicate their folding properties and permeabilizing effects. Despite the advances in understanding how these proteins and peptides mediate pore formation, the role of different N-terminal segments in inducing membrane curvature is still unclear.
View Article and Find Full Text PDFUnlabelled: The chloroplast Twin Arginine Transport (cpTAT) protein translocation pathway is one of the thylakoid membrane's two protein transport pathways for getting proteins into the lumen. The cpTAT system distinguishes itself by transporting fully folded proteins across the thylakoid, using the sole energy source of the proton motive force (PMF). The cpTAT pathway is evolutionarily conserved with the TAT pathway found in many bacteria and archaea.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!