Lactobacillus plantarum antimicrobial peptide Y8-2: A new strategy against Toxoplasma gondii

Toxoplasma gondii is an important foodborne zoonotic parasite that is estimated to have infected one-third of the world's population. However, there are no specific drugs or vaccines to treat toxoplasmosis in humans. Therefore, there is an urgent need to develop safe and effective ways for toxoplasmosis. The antimicrobial peptide Y8-2 was isolated from the supernatant of Lactobacillus plantarum Y8 fermentation that was involved in this study. Flow cytometry analysis showed that Y8-2 had a significant killing effect on tachyzoites; this result, combined the results of SEM and TEM, suggested that Y8-2 could deform cells, disrupt the integrity and permeability of tachyzoite cell membranes, resulting in cytoplasmic vacuolization and extravasation. In addition, Y8-2 significantly inhibited the proliferation of tachyzoites at 12 h and 24 h and elevated the levels of IL-12p70 and TNF-α after infection with Ana-1 cells. Plaque experiments verified that Y8-2 can inhibit tachyzoites invasion and proliferation and significantly reduce the plaque area. Our study provides a new strategy for developing a safe and effective method for the treatment of toxoplasmosis and provides data to support the treatment of toxoplasmosis with LAB metabolites, thus broadening the prospects for the development and utilization of LAB. • Antimicrobial peptide Y8-2 was isolated from the supernatant of L. plantarum fermentation. • Y8-2 has a killing effect on tachyzoites. • Y8-2 can disrupt the cell membranes and internal structures of tachyzoites. • Y8-2 can inhibit tachyzoites invasion and proliferation, participate in immune regulation. • Our study can promote the development and utilization of lactic acid bacteria.