It is a well-known fact that bacteria are very resourceful in adapting to new environments. A team of researchers has discovered a new way bacteria can adapt to certain environments: a sponge that absorbs certain messengers. The study was published in the journal Molecular Cell.
This study was conducted at the Institute for Molecular Infection Biology at the University of Wurzburg as well as at the Helmholtz Institute for RNA based Infection Research. Professor Jorg Vogel, who was the Chair of Molecular Infection Biology I (JMU) and Managing Director for the HIRI, discovered new details about these signalling pathways. A study published in “The Lancet” earlier revealed that at least 1.27million people die each year from infections with bacteria that is resistant to standard antibiotics. The authors were concerned that this number could rise up to ten millions by 2050.
This made it urgent to search for new compounds that can be used to combat resistant bacterial strains. Programmable RNA-based antibiotics could be a possible option. This required a thorough understanding of the key RNA-based signalsling pathways and mechanisms involved in an infection. Gianluca Matera is a Ph.D. student at IMIB and provided additional information about the background of the paper he coauthored with Jorg Vogel. He explained that many bacteria, including Salmonella enterica and Escherichiacoli, have a cell membrane consisting of an inner and outer membrane. This envelope serves two main purposes: it protects the bacteria from the environment, but it also needs to allow the bacteria to access nutrients that they need to thrive.
Many RNA entities interact to control which substances can pass through cells and which are blocked at a time. This allows bacteria to protect themselves from antibiotics. Researchers have identified an “RNA sponge” as a new protagonist in Salmonella enterica. These sponges belong to the “smallRNA” category. The Wurzburg study revealed that OppX, an RNA sponge, mimicked the binding target of a special, sRNA (the so-called MicF, sRNA) in the bacterial outer membrane and intercepted it before it reached its destination. It absorbed it like an sponge.
The MicF sRNA was a key component of the processes within the bacterial envelope. “The outer membrane and inner membranes of a bacterial envelope cannot function independently. There must be mechanisms that allow them to communicate with one another. Gianluca Mattera explained that MicF, a small non-codingRNA, is one type of such regulators. The Hebrew University of Jerusalem developed a new technique that allowed the junior scientist to identify all the interacting partners of all the sRNAs found in Salmonella. This was done in one step.
Matera stated that OppX was a method of increasing membrane permeability. This is done by increasing the expression one of the main pores within the bacterial membrane. OmpF is the scientific term for this pore. The OppX sponge will limit the growth of the bacterium, especially in a nutrient poor environment. However, if enough OppX is available, the OmpF pores within the membrane become more active and increase the uptake of nutrients.
When bacteria is attacked by antibiotics, the OmpF pores play a crucial role. The substances use them to enter the cells. Matera stated, “Indirectly OppX may have an impact on antibiotic efficacy through boosting OmpF formation and thus the uptake the antibiotic itself.” OppX is the first known regulator for MicF activity. The recently published data supports the idea that OppX may be the most important, if certainly the only, sponge for MicF sRNA. According to the study authors, it is important to understand the cellular activity MicF.
These new findings are based on laboratory-based studies of bacteria that was grown in vitro. The next challenge for scientists will be to extend these studies into more “realistic” conditions, according to Jorg Vogel. Jorg Vogel explained that the first step in this direction was already taken. “We are currently decoding RNA interactomes of Salmonella in infected hosts cells.” “Antibiotic resistance” is a major threat to our health. Our basic research aims to help develop new therapeutics. (ANI)
(This story was not edited by Devdiscourse staff. It is generated automatically from a syndicated feed.
