Chagas Parasite Secretes Strange String of Beads

By Jennifer Frazer on February 16, 2016

"Sleeping Sickness parasite Secretes Strange String of Beads

A sinister string of beads made by the organisms that cause sleeping sickness helps the parasite both elude our defenses and make us sick.

What you are about to see is something I have never seen any single-celled organism do before: deploy what appears to be a knotted rope."

In this video a trypanosome is caught spewing out a string of pearls. It's clear, microscopic, and a little hard to see... still pics on the website are very sharp though.


"But what is it doing in that video? Scientists at the University of Georgia, the Pacific Northwest National Laboratory, and the University of Texas at El Paso tried to find out, and reported their results in Cell last month. What they discovered was unsettling both in what implied about how trypanosomes make us sick, but also about their ability to elude our defenses.

To understand why, you need to know a little bit about trypanosome biology. Humans are actually immune to many trypanosome diseases by virtue of a suite of molecules called trypanosome lytic factors (TLF). These molecules circulate in our blood and blow up trypanosomes by punching holes in their sides, more or less (hence “lytic”).

However, the trypanosome that causes sleeping sickeness – Trypanosoma brucei rhodesiense – produces a virulence factor that allows it to get around these defenses by binding to and neutralizing TLF. This factor is called the serum-resistance associated protein (SRA). Unfortunately, biologists, like engineers, are lovers of alphabet soup. So I’ll sum up to help clarify: SRA made by trypanosomes allows them to defeat defensive TLFs made by humans --- got it?"

More info and pics:
http://blogs.scientificamerican.com/artful-amoeba/sleeping-sickness-parasite-...