Anti-Protozoan Activities of Polar Fish-Derived Polyalanine Synthetic Peptides.

Chagas disease, sleeping sickness and malaria are infectious diseases caused by protozoan parasites that kill millions of people worldwide. Here, we performed in vitro assays of , , and synthetic polyalanine peptides derived from the polar fish toward , and activities. We demonstrated that the peptides and were effective to inhibit growth. In addition, structural analyses using molecular dynamics (MD) studies showed that penetrates deeper into the membrane and interacts more with phospholipids than , corroborating the previous in vitro results showing that acts within the cell, while acts via membrane lysis. In conclusion, polyalanine and presented activity against bloodstream forms of , thus encouraging further studies on the application of these peptides as a treatment for sleeping sickness.