Researchers have discovered a new mechanism in which Gram-negative bacterium communicates with our bodies and makes us sick.
The study was based on understanding the way through which Gram-negative bacterium can be blocked and the release of toxins can be controlled. It reasoned the mechanism of bacteria communicating with human bodies through the transportation of small molecules. These molecules facilitate the production of outer membrane vesicles.
The initial assumption that this production happens by controlling gene expression turned out to be wrong. It was, in reality, found that these molecules get bud off from the surface of the bacterium and constitute highly concentrated toxins.
The production of these toxin delivery vehicles is empowered when the communication molecule get inserted into the membrane of bacteria.
The lead researchers of the study, created a model to understand this mechanism in detail. The model helped them to know how the molecule in a very short period of time, interacted with the membrane.
Jeffrey W. Schertzer, an assistant professor from the Department of Biological Sciences said, “Our most important finding is that the communication molecule needs to enter the membrane in a very specific way. It folds itself like a book, then will expand once it has entered the membrane.”
He also said, “This study was a testament to how beneficial interdisciplinary work can be. We had reached a limit with what could be done experimentally and needed Dr. Yong’s model to develop a rationale for how the molecule was interacting with the membrane. Most importantly, this work has generated a wealth of new questions that we are now continuing to investigate.”
Xin Yong, an assistant Professor from the Department of Mechanical Engineering said, “Gram-negative bacteria likely all have similar types of communication molecules. We focused on the PQS [Pseudomonas Quinolone Signal] molecule of Pseudomonas aeruginosa because it was the first discovered and is the best studied. Other Gram-negative species, such as E. coli, may be transferring their own communication molecules in a similar way.”
They found that the communication molecule had a very flexible head and tail. In their further studies, they aim at finding out how the tail reacts in the absence or modification of the head and how the head reacts if the tail is removed or modified.
This study could help researchers in understanding multispecies interactions which could in turn help in controlling the risk of infections because of these interactions.