VERMILLION — A research team at the University of South Dakota led by microbiologist Michael Chaussee, Ph.D., is working on a possible therapeutic treatment for patients with Streptococcus pyogenes that does not utilize antibiotics. Human infection with Streptococcus pyogenes ranges in clinical severity from asymptomatic infection and uncomplicated “strep throat” to life-threatening diseases such as toxic shock syndrome.
Chaussee’s goal is to better understand why some people are asymptomatic whereas others will die, because the bacteria look almost identical in both situations.
When bacteria become invasive by entering the blood, lung or deep tissue, mortality rates can be up to 50 percent. The current treatment for these types of invasive diseases is to use a variety of antibiotics, but unfortunately, bacteria can become either resistant or tolerant to said antibiotics.
The USD research team has found a peptide that controls bacteria’s ability to produce toxins and it also interrupts the bacteria’s ability to communicate utilizing signaling pathways. The research team can disrupt bacteria’s ability to survive in blood by artificially adding this peptide.
“We envision the treatment would be IV administration for patients with life-threatening invasive Streptococcus pyogenes infections,” said Chaussee. “The therapeutic is a small molecule and specifically targets Streptococcus pyogenes, which means it would not disrupt the normal microbiome, which is beneficial.”
The next steps for this research project involve characterizing how the peptide affects toxin production and testing it in vivo. It is also possible that this therapeutic could target other bacterial species, such as Streptococcus pneumoniae, the most common bacterial cause of pneumonia.