A2: Microbes in the News – Amoeba can help kill bacteria protected by biofilm

Article:  Study finds amoeba “grazing,’ killing bacteria usually protected by film (April 17, 2017)

Source: University of Wisconsin-Madison

Study finds amoeba “grazing,” killing bacteria usually protected by film


An Amoeba species called Dictyostelids  is capable of penetrating biofilm in order to eat the bacteria within. Bacteria tested were  Pseudomonas aeruginos,  Pseudomonas syringae,  Klebsiella oxytoca and  Erwinia amylovora.  All these bacteria are capable of creating biofilms and were harmful to humans or plants. This also opens up further studies of methods of killing bacteria without resorting to antibiotics, which the bacteria may grow resistances to.

We’ve learned about how certain microbes can create biofilms to protect and help with survival. This article is about how we can get around that. Also my isolate happened to be a bacteria capable of creating biofilms (S.epidermidis)

Critical Analysis:

Most of the article was regarding the scientists’ steps in finding out about this amoeba rather than the actual science behind it. However, it did use many quotes by the scientists so it did give assurances on the accuracy of the report.


What is the molecular mechanism of how the amoeba can “eat” biofilm?

Will using amoeba to kill bacteria be safe for humans/plants in vivo?


5 Comments for “A2: Microbes in the News – Amoeba can help kill bacteria protected by biofilm”



I agree with your analysis, in that they could have used more detailed explanations about how the amoeba actually breaks down the biofilm. I am curious to see whether this can be adapted to be used to treat humans. In response to your second question about whether the amoeba is safe for humans, they do address the fact that the amoeba is not known to be pathogenic. They also go on to say that they have had successful trials in mice. Though mice are very different from humans, this is still a promising sign.

If it turns out that the amoeba are harmful to humans, maybe we can instead recreate their way of deteriorating the biofilms. If we can figure out what chemical combinations they use to break down the biofilms, maybe we can incorporate that into our medical treatment rather than using the amoebas themselves.

Katrina Dowell


I read another article covering the same subject, it mentions that the amoeba are not pathogenic… I’m thinking that once they’re done having a snack, they will simply die off or clear from the system – given there isn’t another type of fodder they’re interested in. They eat by surrounding tiny particles of food with pseudopods, forming a bubble-like food vacuole which then digests the food.



This was a very interesting article – I like how it presents an unconventional approach to destroying biofilms. When thinking about amoeba this as a treatment to remove biofilms in animals and plants we should consider if any byproducts of this process could be toxic to the hosts. If it is pretty harmless it would be an interesting idea to use harmless amoeba to remove unwanted biofilms in plants and animals.



I agree with you that the credibility of the methods of the scientists wasn’t in question, but I feel that that would kind of lose the majority of the public that may try to learn about science. I think it should have talked even more about implications of what this research could yield for our favor rather than notifying how it was discovered, and that would pique the interest of laymen more. I did like the honesty during the paper where they basically wouldn’t have come across their finding if they felt more confident in their knowledge of the field as they would have felt they would have known too much. As an answer to the second question, I feel that results could be promising to use on plants or animals in vivo. As long as the benefits of killing the bacteria outweigh the side effects, it is a good option! Methods don’t have to be perfect to be useful. We still use chemotherapy, which kills us over time, because the ends outweigh the side affects for the time being and therefore it is successful, in my eyes. This could be along the same lines.



I love the idea presented in this article! Wouldn’t that be great if we could harness amoebas to fight against pathogens?

Yes, I noted as well that the article primarily focused on how they came to their conclusions that this organism could be used to break down biofilms produced by bacteria which negatively impact both humans and plants. I do wish that they had included a bit more about what they knew concerning its mechanisms of action.

You have some good questions… I do wonder if perhaps the amoeba produces a certain type of enzyme which plays a role in breaking down biofilm? I noted there were some studies which mentioned some other interesting enzymes that it can produce, so I imagine that could be part of its mechanism of action in this situation as well. I also noted that, in the article with the quotes from the main investigator, he did mention that this amoeba has not been shown to cause harm in the animal testing thus far. He also mentioned that this amoeba could potentially be used in removing populations of methicillin-resistant Staphylococcus aureus (MRSA) from the nasal passages, so I am assuming that it is safe to use, at the very least in specific areas of the body. In addition, he also mentioned using it to disinfect surgical sites prior to surgery, indicating that he is assuming that this amoeba is also safe to get into the bloodstream.

I hope they release more research on this soon!