Question: If you interrupt the bacteria’s conversations and stop bacteria, will the bacteria become extinct?

Katie Fala answered on 13 Nov 2019:

That’s a great question, the honest answer is that at the moment we are not sure. Some people say no, because stopping them from talking to one another does not kill them, just makes them less effective at surviving. In theory they would still be alive, but would not make biofilms or harm humans by causing active infection. Other people say that it could because by stopping a bacterial cell from shielding itself in a biofilm or infecting a human, you are blocking the two main ways in which it lives in the world.

It’s a really interesting question to think about because, as we understand antibiotic resistance, while your drug might kill 99.9% of bacteria, the odds are that 0.1% will randomly survive, perhaps due to developing a mutation or picking up genes from other bacteria that make them resistant to the antibiotic. So while you killed most of them, that 0.1% can then go on, multiply, and in the blink of an eye you have a massive population of antibiotic-resistant bacteria. We think of killing as a strong selective pressure, while other methods such as quorum quenching (interrupting bacterial conversations) that don’t kill the bacteria have weaker selective pressure because in theory there is a wider gene pool in the bacterial population and less incentive for a bacteria to develop resistance.

More widely, not all bacteria communicate with one another (although there is evidence that many of them do) and I don’t think that bacteria would become extinct, I think that would be a very bad thing for different microbiomes and ecosystems. I hope that the compounds that I am studying can be targeted to just control those bacteria that can cause disease or economic loss, while leaving the benign or neutral bacteria intact.

Let me know if anything in that didn’t make sense or if you have any follow-up questions 🙂