Researchers from the "Balance of the Microverse" Cluster of Excellence and the University of Jena have identified an RNA sponge that controls the dynamics of quorum sensing and associated biofilm formation in the bacterium Vibrio cholerae. Cholera bacteria do not form the disease-causing biofilm until they reach a certain cell density, which they determine by using quorum sensing. The team led by Professor Kai Papenfort published their results in the journal Nature Communications.

In Vibrio cholerae, the causative agent of cholera, a microbial communication mechanism known as quorum sensing, plays a crucial role in the production of virulence factors and thus influence the infectivity of the bacteria. The researchers led by Professor Kai Papenfort from Jena are intensively studying the activities that take place during this bacterial communication process. In the past they discovered several examples of certain small regulatory RNAs (sRNAs) playing a fundamental role in controlling quorum sensing and virulence of Vibrio cholerae.
"The regulatory role of these small RNAs was previously known to us in a rather exemplary manner and global studies on this were lacking," says Papenfort. "In our sequencing, we found numerous unknown interactions, which in turn led us to the discovery of several sRNA sponges," Papenfort adds. These RNA sponges belong to a class of regulators that interact with other small RNAs to abolish their effects.
Papenfort and his team studied one of these sRNA sponges, called QrrX, in more detail. "We found that the QrrX sponge has a significant effect on quorum sensing and biofilm formation of Vibrio cholerae," Papenfort explains. According to the scientist, understanding quorum sensing and thus the communication of the bacteria offers the possibility of being able to actively intervene in their communication: "If we could speak the microorganisms’ language, we could, for example, prevent the cholera bacteria from becoming virulent by fooling them into ‘thinking’ that they have not yet assembled enough other bacteria around them"
With the findings from this study, the scientists around Papenfort are making an important contribution to research in the Cluster of Excellence "Balance of the Microverse" at Friedrich Schiller University Jena. Its goal is to create a holistic understanding of microorganisms, their interaction and communication with each other, as well as with their environment.

Original publication:

Huber M, Lippegaus A, Melamed S, Siemers M, Wucher BR, Hoyos M, Nadell C, Storz G, Papenfort K: An RNA sponge controls quorum sensing dynamics and biofilm formation in Vibrio cholerae, Nature Communications (2022), DOI: https://doi.org/10.1038/s41467-022-35261-x

Author: Alena Gold
Illustration: Kai Papenfort

12/12/2022