Vegetables rotting? Check bacteria conversation

May 30, 2017

Bacteria "conversation" may be an early trigger for plant pathogens virulence, show scientists from Instituto Gulbenkian de Ciencia (IGC, Portugal). In a study published now in the open access journal mBio*, the research team led by Karina Xavier discovered that the virulence of pathogenic bacteria is precipitated in the presence of other pathogenic species that release chemical signals to the environment.

Karina Xavier's laboratory has been investigating how bacteria "talk" to each other in order to adjust their behaviour to environmental changes or presence of other species. "Bacteria use a 'language' made of small chemical molecules. When present in high numbers, bacteria start releasing these molecules, which will then be sensed by other bacteria, either from the same or different species. These molecules work as signals triggering bacterial behaviours that are only productive when bacteria are working together as a group boosting their virulence, for instance", explains Karina Xavier.

In this study, the IGC team focused on Pectobacterium wasabiae, a bacteria species included in an important group of plant pathogens. The virulence of these pathogens is characterised by the production of enzymes that degrade the cell wall of cells rooting plant tissue. The researchers were interested in understanding how this bacterium integrates different signals to regulate its virulence.

Using a genetic approach that enabled them to inhibit genes involved in the mechanism that induce virulence, the research team could observe what happened to the behaviour of this species. Typically, Pectobacterium wasabiae needs to be at a high density to produce the chemical molecules that will activate their virulence response. But now, the IGC team discovered that its virulence response could be triggered earlier, even at low densities, if these bacteria eavesdrop on signals released by other pathogenic species present in the environment.

Karina Xavier explains: "The molecules produced by different bacteria species in order to communicate to each other and to help them sense the status of their surroundings are the key players in the virulence response of bacteria. Blocking these signals and inhibiting the communication established between bacteria, is a strategy that needs to be further explored and taken into consideration to prevent pathogens' virulence".
-end-
This study was conducted in the IGC and funded by Fundacao para a Ciencia e a Tecnologia, and the Howard Hughes Medical Institute.

*Valente RS, Nadal-Jimenez P, Carvalho AFP, Vieira FJD, Xavier KB. 2017. Signal integration in quorum sensing enables cross-species induction of virulence in Pectobacterium wasabiae. mBio 8:e00398-17. https://doi.org/10.1128/mBio.00398-17

Instituto Gulbenkian de Ciencia

Related Bacteria Articles from Brightsurf:

Siblings can also differ from one another in bacteria
A research team from the University of Tübingen and the German Center for Infection Research (DZIF) is investigating how pathogens influence the immune response of their host with genetic variation.

How bacteria fertilize soya
Soya and clover have their very own fertiliser factories in their roots, where bacteria manufacture ammonium, which is crucial for plant growth.

Bacteria might help other bacteria to tolerate antibiotics better
A new paper by the Dynamical Systems Biology lab at UPF shows that the response by bacteria to antibiotics may depend on other species of bacteria they live with, in such a way that some bacteria may make others more tolerant to antibiotics.

Two-faced bacteria
The gut microbiome, which is a collection of numerous beneficial bacteria species, is key to our overall well-being and good health.

Microcensus in bacteria
Bacillus subtilis can determine proportions of different groups within a mixed population.

Right beneath the skin we all have the same bacteria
In the dermis skin layer, the same bacteria are found across age and gender.

Bacteria must be 'stressed out' to divide
Bacterial cell division is controlled by both enzymatic activity and mechanical forces, which work together to control its timing and location, a new study from EPFL finds.

How bees live with bacteria
More than 90 percent of all bee species are not organized in colonies, but fight their way through life alone.

The bacteria building your baby
Australian researchers have laid to rest a longstanding controversy: is the womb sterile?

Hopping bacteria
Scientists have long known that key models of bacterial movement in real-world conditions are flawed.

Read More: Bacteria News and Bacteria Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.