Extracellular vesicles proteomics analysis virulence of different Toxoplasma gondii strains and reveals a novel SAG-related sequences protein SRS49D that play an role in Toxoplasma gondii fitness using CRISPR/cas9

We performed TMT (tandem mass tag) analysis to compare Ev’s protein changes of RH (type I) and PRU (type II) strain, with the aim of elucidating the complex relationship between proteomic variations and parasites virulence.A total of 1377 T. gondii proteins were detected and according to the standard criteria (adjusted p-value of <0.05 and > 1.5 or < 0.67-fold change), 180 upregulated and 160 downregulated proteins were identified in RH-Evs compared with PRU-Evs. DEPs including secretory proteins, SRS protein and metabolic enzymes. Functional enrichment analyses revealed roles for DEPs in targeting parasite protein export and metabolism-related signaling pathways.We constructed the knockout strains of SRS46 and SRS49D in type I RH strains using the CRISPR-Cas9 system and characterized their functional role in vitro.