New study details long-sought mechanisms and structures

Bacterial infections pose significant challenges to agriculture and medicine, especially as cases of antibiotic-resistant bacteria continue to rise. In response, scientists at Texas A&M AgriLife Research are elucidating the ways that bacteria-infecting viruses disarm these pathogens and ushering in the possibility of novel treatment methods.
In their recent study published in Science, Lanying Zeng, Ph.D., a professor, and Junjie Zhang, Ph.D., an associate professor, both in the Texas A&M College of Agriculture and Life Sciences Department of Biochemistry and Biophysics, detailed a precise mechanism by which phages disable bacteria.
The collaborative effort also involved:

• Yiruo Lin, Ph.D., research assistant professor in the Texas A&M College of Engineering Department of Computer Science and Engineering.
• Matthias Koch, Ph.D., assistant professor in the Texas A&M College of Arts and Sciences Department of Biology.
• Zemer Gitai, Ph.D., and Joshua Shaevitz, Ph.D., professors in the Princeton University Department of Molecular Biology and Department of Physics, respectively.
• Yinghao Wu, Ph.D., associate professor in the Albert Einstein College of Medicine Department of Systems and Computational Biology.

Together, the team worked to explain a series of interactions scientists have sought to understand since the early 1970s.

The need for new treatments

Pseudomonas aeruginosa is a type of bacteria that can cause infections in the blood, lungs and occasionally other parts of the body. These infections are especially common in healthcare settings, which often encounter drug-resistant bacteria. According to the Centers for Disease Control and Prevention, there were over 30,000 cases of multi-drug resistant P. aeruginosa infections among hospitalized patients in 2017.
The prevalence of antibiotic-resistant Pseudomonas infections makes them a practical point of focus for phage therapy, a type of treatment method using bacteriophages, or phages, that researchers at the Texas A&M Center for Phage Technology are exploring as an alternative to typical drugs.
Zeng and Zhang, co-directors at the center along with Jason Gill, Ph.D., associate professor in the Department of Animal Science, are exploring the usefulness of phages, even beyond phage therapy, by diving into the structures and mechanisms at play.

Targeting the pilus

One of the factors that allows P. aeruginosa to transmit antimicrobial-resistant genes among each other, as well as move around and create difficult-to-treat structures called biofilms, is an appendage called a pilus, named after the Latin word for spear. These cylindrical structures extend from the surface of bacteria.
Some phages make use of bacterial pili by attaching to them and allowing bacteria to reel the phage to the surface, where the phage can start infecting the bacteria.
In their study in Science, co-first authored by Texas A&M graduate students Jirapat Thongchol and Zihao Yu, the researchers studied this process step by step using fluorescence microscopy, cryogenic-electron microscopy and computational modeling. They observed how a phage called PP7 infects P. aeruginosa by attaching to the pilus, which then retracts and pulls the phage to the cell surface.
This content is taken from Texas A&M AgriLife Communications

List of Referenes

Cite This Article as

"Researchers resolve old mystery of how phages disarm pathogenic bacteria", MachPrinciple, April 17, 2024, https://machprinciple.com/post/Researchers-resolve-old-mystery-of-how-phages-disarm-pathogenic-bacteria