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Palma-Duran, S. A.

Publications and source records attributed to Palma-Duran, S. A..

2 recordsLinked to original sources

A palmitoyl transferase chemical genetic system to map ZDHHC-specific S-acylation

The 23 human ZDHHC S-acyltransferases catalyze long-chain S-acylation at cysteine residues across an extensive network of hundreds of proteins important for normal physiology or dysregulated in disease. Here we present a technology platform to directly map the protein substrates of a specific ZDHHC for the first time at the whole proteome level, in intact cells. Structure-guided engineering of paired ZDHHC hole mutants and bumped chemically tagged fatty acid probes enabled probe transfer to specific protein substrates with excellent selectivity over wild type ZDHHCs. Chemical genetic systems were exemplified for five ZDHHCs (3, 7, 11, 15 and 20), and applied to generate the first de novo ZDHHC substrate profiles, identifying >300 unique and shared substrates across multiple cell lines and S-acylation sites for novel functionally diverse substrates. We expect that this powerful and versatile platform will open a new window on S-acylation biology for a wide range of models and organisms.

molecular biology↗

A choline-releasing glycerophosphodiesterase essential for phosphatidylcholine biosynthesis and blood stage development in the malaria parasite

The malaria parasite Plasmodium falciparum synthesizes significant amounts of phospholipids to meet the demands of replication within red blood cells. De novo phosphatidylcholine (PC) biosynthesis via the Kennedy pathway is essential, requiring choline that is primarily sourced from host serum lysophosphatidylcholine (lysoPC). LysoPC also acts as an environmental sensor to regulate parasite sexual differentiation. Despite these critical roles for host lysoPC, the enzyme(s) involved in its breakdown to free choline for PC synthesis are unknown. Here we show that a parasite glycerophosphodiesterase (PfGDPD) is indispensable for blood stage parasite proliferation. Exogenous choline rescues growth of PfGDPD-null parasites, directly linking PfGDPD function to choline incorporation. Loss of PfGDPD reduces choline uptake from lysoPC, resulting in depletion of several PC species in the parasite, whilst purified PfGDPD releases choline from glycerophosphocholine in vitro. Our results identify PfGDPD as a choline-releasing glycerophosphodiesterase that mediates a critical step in PC biosynthesis and parasite survival.

microbiology↗