The toxin, called microcystin, poses a serious public health threat, as it can damage the liver and nervous system and may be linked to some cases of neurodegenerative diseases. Microcystin is produced by cyanobacteria, or blue-green algae, which are abundant in freshwater lakes, rivers, and estuaries around the world. Although algal blooms can be controlled by reducing the levels of nutrients in the water, the new research may offer an even more efficient way to mitigate their impact.
"Our research team hypothesized that a previously unknown protein was the target of microcystin," said lead author Jeffrey Noel, a professor at the UT Austin College of Pharmacy. "We used X-ray crystallography, a technique that enables scientists to deduce the three-dimensional structure of a protein, to experimentally validate the hypothesis and uncover how microcystin binds to its molecular target."
The researchers found that microcystin binds to the protein phosphatase 1 (PP1) in cyanobacteria in a way that prevents PP1 from doing its job of regulating other proteins in the cell. As a result, microcystin can disrupt cellular processes and lead to cell death.
"This discovery provides a new starting point for the development of potential treatments for microcystin poisoning," said co-author Timothy Nelsestuen, a professor at the UT Austin Dell Medical School. "We now understand how microcystin exerts its toxic effects, which could lead to the identification of new drugs or strategies to block its action and protect human health."
The findings are published in the journal Nature Communications.
