Project description:Background Sporothrix brasiliensis and Sporothrix schenckii are the main etiological agents of sporotrichosis. These pathogens release extracellular vesicles (EVs), which are key transport structures involved in virulence and host–pathogen interactions. EVs from S. brasiliensis and S. schenckii have been exclusively under liquid culture conditions, with analyses focused on their protein composition and functional roles. However, noinformation is currently available regarding the small molecule composition of Sporothrix EVs, and the extent to wich S. schenckii and S. brasiliensis share or differ in their EVs cargo remain unknown. Methods We isolated EVs from S. brasiliensis (strain 5110) and S. schenckii (strain 1099-18) following cultivation on solid medium, and characterized the samples using a combination of nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), proteomics, and small molecule identification. Based on the EV composition, subsequent analyses included biochemical assay to assess cell-assocaited enzyme activity and a functional model of Sporothrix adhesion to type I collagen in the presence of isoleucine-proline-isoleucine (IPI), a peptide component found in EVs produced by both S. schenckii and S. brasiliensis. Results EVs from both S. brasiliensis and S. schenckii exhibited a high protein diversity, encompassing components related to essential cellular processes and virulence mechanisms. Only a small fraction of the identified proteins was shared between the two species, and a similar pattern was observed for the small molecules. Among the common molecules was IPI, previously described in Cryptococcus EVs. IPI is an inhibitor of dipeptidyl peptidase IV (DPP4), which was detected on the surface of S. brasiliensis and S. schenckii. Both IPI and an antibody against DPP4 effectively reduced Sporothrix adhesion to type I collagen, a major component of the host extracellular matrix. Conclusion Our study reveals an unprecedented level of proteomic and metabolomic complexity in Sporothrix EVs, uncovering novel molecular features and identifying IPI as an inhibitor of fungal adhesion to collagen.
