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Iorillo, O.

Publications and source records attributed to Iorillo, O..

2 recordsLinked to original sources

Complexome profile of mitochondrial complexes in the myzozoan parasite of oysters, Perkinsus marinus

Mitochondrial complexes, such as the mitochondrial electron transport chain (mETC), the F1Fo-ATP synthase and the mitochondrial ribosome, are centrally important for mitochondrial function. Recently, an unexpected diversity in the composition of these complexes across unicellular eukaryotic lineages, with the apicomplexan parasites featuring prominently, has been revealed. However, whether the observed enlarged and divergent mitochondrial complexes are conserved across the wider Myzozoan lineage has not been investigated. Here, using a complexome profiling proteomic approach, we have characterised the composition of the mitochondrial complexes of the myzozoan parasite of oysters, Perkinsus marinus. We show that it shares with Plasmodium and Toxoplasma huge ATP synthase and mETC complexes. Moreover, the Perkinsus mitoribosome possesses many of the divergent features recently discovered in apicomplexans, such as an expanded subunit repertoire and the inclusion of RAP-domain and ApiAP2-like proteins as ribosomal proteins. Our study reveals the divergent subunit composition of mitochondrial complexes is an ancestral and highly conserved feature of Myzozoa.

microbiology↗

Subcellular proteomics of Paradiplonema papillatum reveals digestive capacity of the cell membrane and the plasticity of peroxisomes across euglenozoans

Diplonemids are among the most diverse and abundant protists in the deep ocean, have extremely complex and ancient cellular systems, and exhibit unique metabolic capacities. Despite this, we know very little about this major group of eukaryotes. To establish a model organism for comprehensive investigation, we performed subcellular proteomics on Paradiplonema papillatum and localized 4,870 proteins to 22 cellular compartments. We additionally confirmed the predicted location of several proteins by epitope tagging and fluorescence microscopy. To probe the metabolic capacities of P. papillatum, we explored the proteins predicted to the cell membrane compartment in our subcellular proteomics dataset. Our data revealed an accumulation of many carbohydrate active enzymes (CAZymes). Our predictions suggest that these CAZymes are exposed to extracellular space, supporting proposals that diplonemids may specialize in breaking down carbohydrates in plant and algal cell walls. Further exploration of carbohydrate metabolism revealed an evolutionary divergence in the function of glycosomes (modified peroxisomes) in diplonemids versus kinetoplastids. Our subcellular proteome provides a resource for future investigations into the unique cell biology of diplonemids.

cell biology↗