Microbes in the news (num 2/3): Microbial Predation

Link: Predatory bacteria can wipe out superbugs, study says (bbc.co.uk)

Publish date: 24 Nov 2016

Synopsis: A study out of the Medical Research Centre CMBI and Nottingham University (paper) has found that inoculation of  Bdellovibrio bacteriovorans into zebrafish infected with  Shigella flexneri allowed the fish to clear the infection without the use of antibiotics. B. bacteriovorans is a parasitic bacterium that reproduces inside host bacterial cells before lysing the host cell and releasing the  daughter cells similar to viral lytic cycle.  The authors propose  that the mechanism is that the lysed  Shigella cell wall pieces attract the attention of the infected organism’s immune system to recruit phagocytes and clear the infection. They suggest that  B. bacteriovorans may be useful to treat multidrug-resistant infections in humans as it has not yet been reported to cause disease in humans.

Connections: In addition to the lytic viral life cycle, we recently discussed how the innate immune system detects and responds to potential pathogens. We have also discussed antibiotics, antibiotic resistance, and the use of phage therapy to combat it.

Critical thinking: The use of parasitic bacteria to cure an infection is reminiscent of phage therapy to destroy multidrug-resistant bacteria. It sounds absurd, but this seems to me the most effective way to move into the post-antibiotic era: intentional “infections” to stave off worse infections.

Question: Does this sound like a promising therapy or an absurd act of desperation?

4 Comments for “Microbes in the news (num 2/3): Microbial Predation”



I found your post to be very interesting, and when I read the news article I got even more intrigued. I think the prospect of this is very interesting and especially in the light of what is happening with antibiotics and antibiotic resistance, and I do agree it does sound absurd, but also extremely efficient.

To try and answer your question, I do think it is promising, and with more research and more trials it might work out. and slowly but surely start replacing some of the use of antibiotics, which would be great. I do think a lot of the research done on methods to try and replace antibiotics can be more an act of desperation than they are functional, but the more we try the closer we get to solving the problem.



This is very interesting, especially about how the bacterium acts like a virus. We have not really looked at that as a lifestyle for bacteria, so to see that is interesting. The future applications to this will be interesting, but it will basically be like a antibiotic. Once mechanisms to combat it arise in the target bacterium, it will have a much lesser effect. The applications of it look promising though, but we should treat it like another antibiotic.



I like the idea that some bacterium would be able to assist us in killing off harmful bacterial species mostly because unlike antimicrobial drugs the bacterium is in a host-parasite relationship with the other bacterium, and has the ability to change in response to a change in the microbes it consumes potentially leading to a cure that will work for long enough that antimicrobial-resistant microbes will go away and we can alternate treatments for a long time to come.
To answer your question, I believe that this could be a really good way to treat antimicrobial-resistant microbes as a potential treatment, but I imagine the bacterium does not kill many different microbes and we would need multiple different microbes to kill off various harmful microbes, which becomes impractical at some point, so all I can say is that it looks good on paper.



The idea that harmful bacteria could be eliminated from a body without the use of antibiotics is very interesting. It could be a great way to treat antibiotic resistant bacteria or just to simply lower the use of antibiotics in a society. How open would society be to this idea? There is obviously still a lot more research to be conducted. This article raises many questions. Would there ever be a risk to health of the organism being treated? Could this potentially be used in humans and would the risks outweigh the benefits? Microbes could potentially be artificially altered in some way to allow them to target a specific harmful bacterium while still remaining safe to the host. This is a very interesting prospect.