UM students discover a new protein while investigating the question: “Why does Streptococcus make you sick?”
Strep throat, something we’ve all had at some point in our lives, is caused by the bacteria Streptococcus pyogenes. Infection by Streptococcus can be fatal in serious cases and is the leading cause of death among flesh-eating diseases resulting in over half a million deaths annually. That scratchy, sore feeling at the back of your throat is a result of Streptococcus pyogenes infected by viruses called bacteriophages. These “phages” carry the genes for toxins that are responsible for strep throat, and when they invade Streptococcus pyogenes, they transfer these genes, enhancing the bacterium’s ability to cause infection.
However, many people carry Streptococcus pyogenes on their bodies, and it doesn’t make them sick. Some of the big questions in the field are when, how and why does it make you sick? And why does Streptococcus become a pathogen?
In answering these questions and to understand how phages transform Streptococcus into a deadly pathogen, Dr. Gerd Prehna and his lab have been studying the phage protein paratox (Prx). Two graduate students, Tasneem Hassan Muna and Nicole Rutbeek from the Prehna Lab have discovered that phages use paratox to control the metabolism of Streptococcus, redirecting DNA processing pathways for the benefit of the phage. With help from undergraduate student Julia Horne, the team was able to demonstrate that paratox also likely regulates when it is time for the phage to leave Streptococcus and go on to infect new bacteria. Muna and Horne now have a protein named after them, JM3 which stands for Julia Muna construct 3.
Prehna goes on to tell us that this discovery, published in the Journal of Nucleic Acids Research, has opened many doors for future research projects.
“What’s neat about this project is that it just keeps giving and it keeps opening more doors. We’ve discovered that it binds a whole bunch of other proteins. However many of these proteins are in regulatory pathways that control the biology of Streptococcus in ways that are completely unstudied and not understood at all. Now we have to characterize all these new brand-new proteins and brand-new pathways and understand how they affect the biology and metabolism of Streptococcus”, says Prehna.
Watch the complete interview on the Faculty of Science’s YouTube channel.