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Is it possible for me to locate, without too much difficulty, and culture, at home, a bacteria (like yeast) on plastic?

I tried a similar process with yeast and I was able to culture it on extremely harsh medications at my home. However, I believe due to the lack of food they died.

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Although you should be able to find bacteria that can grow on plastic, I think your criteria of 'not difficult to find' might be a challenging one to meet. Poly(ethylene terephthalate) (PET) is a commonly used plastic, and in 2016 Yoshida et al. discovered a species of bacteria, Ideonella sakaiensis, which can grow using PET as its carbon source. This study was significant enough to be published in the journal Science, and has since been cited over 700 times. Therefore, using impact as a proxy for 'difficulty', it could be said that this was a difficult bacteria to find!

In terms of how they did it, here is an extract from their paper:

We collected 250 PET debris–contaminated environmental samples including sediment, soil, wastewater, and activated sludge from a PET bottle recycling site. Using these samples, we screened for microorganisms that could use low-crystallinity (1.9%) PET film as the major carbon source for growth.

Similarly, only last year Espinosa et al. isolated a strain that was able to grow on Polyurethane, from their paper:

For the isolation of bacteria from soil, three samples from a site rich in brittle plastic waste (Paunsdorf, Leipzig, Germany) were used. ... 150 μL of the diluted soil solutions were added to agar plates containing mineral medium and different concentrations of 2,4-TDA (2, 5, and 10 mM) as sole carbon and energy source.

In both of these studies they isolated bacteria that could grow on plastic, rather than evolving bacteria to grow on it. These bacteria at some point did evolve to grow on plastic, so in theory you could probably evolve a strain that did as well, but it would be easier, although still difficult, to isolate bacteria that already grow on plastic.

EDIT: Adding information on Yeast to respond to question edit

Yeast are actually a member of the fungal kingdom, and are not a type of bacteria. What most people refer to as 'yeast' is a species of yeast, Saccharomyces cerevisiae, which is used in the brewing industry. As far as I am aware, no-one has engineered this yeast, or another yeast, to grow on plastic. However, in 2020 Chen et al displayed the enzyme, PETase, on the surface of the yeast Pichia pastoris. This is the enzyme that the bacteria I mentioned above use to degrade PET. This enabled the yeast to break down PET into other compounds, however the yeast cannot grow using these compounds. If you wanted to engineer a yeast to grow on plastic you would need more enzymes, such as a MHETase, to further break down these compounds into something the yeast can grow on.

As you are looking to use microorganisms to break down plastic for environmental purposes, Taniguchi et al., have written a review, Biodegradation of PET: Current Status and Application Aspects, which discusses the problem. This is from 2019, however, so doesn't include recent developments. You can read a news article from the Guardian, here, that discusses the impressive improvements made in 2020. A key thing to note about the most recent efforts is that they involve using the enzymes that degrade plastic, but not the microbes themselves.

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  • $\begingroup$ Thank you so much for your response, I am also a new contributor so it was really helpful $\endgroup$ – Mikul Rai Feb 25 at 7:19
  • $\begingroup$ Will it be possible to grow yeast to eat plastic? That's what I am trying to research as these researches do say that microbes are slow for now. Would it be possible to contact you? $\endgroup$ – Mikul Rai Feb 25 at 7:25
  • $\begingroup$ By harsh chemicals, I meant, Calcarea hypophosphorosa, Budesonide, Alcohol solution, lactic acid capsules, etc. I also added some other substances for promoting growth - Vitamin E & B, Cod liver oil, milk, etc. $\endgroup$ – Mikul Rai Feb 25 at 7:27
  • $\begingroup$ I would say that you should edit your original question to remove reference to harsh chemicals. This should probably be a separate question. You can also edit your original question to add your additional question about yeast, and I will edit my answer to reflect that. As for contacting me, this is not the StackExchange way as it hides information from the community (see here: meta.stackexchange.com/questions/431/…). $\endgroup$ – Noah Sprent Feb 25 at 11:04
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    $\begingroup$ @MikulRai To be clear, I agree with the link that moving questions to a private forum is not the best way to serve the community. If you have further questions you can post them and I can try to answer, or you can edit your original question. I've also suggested some edits to your question to make it clearer and I'll edit my answer once they're approved. $\endgroup$ – Noah Sprent Feb 26 at 15:03

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