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From another article on the same topic[1]: >The Kyoto researchers identified the gene in the bacteria's DNA that is responsible for the PET-digesting enzyme. T

From another article on the same topic[1]: >The Kyoto researchers identified the gene in the bacteria's DNA that is responsible for the PET-digesting enzyme. They then were able to manufacture more of the enzyme and then demonstrate that PET could be broken down with the enzyme alone. Sounds like this is quite a big step forward in our ability to reduce plastics to more base elements. Has anyone caught what the exact output of this process is? Some waste must be excreted by these microbes, right? [1] http://phys.org/news/2016-03-plastic-munching-bacteria-fuel-recycling-revolution.html#jCp http://phys.org/news/2016-03-plastic-munching-bacteria-fuel-...

x5n1 11y ago
Well if these genes exist somewhere, and we commercialize them. Is it not a matter of time until these genes become more common in bacteria in general and then we can no longer use plastics, I guess then we would have to put some antibacterial in plastics too. Like say a long time period.
- forgotmysn 11y ago
  I'm not a biologist, but I don't think genes are contagious
  - mr_overalls 11y ago
    If they confer a selective advantage, they can quickly spread through a population: https://en.wikipedia.org/wiki/Selective_sweep https://en.wikipedia.org/wiki/Selective_sweep
  - x5n1 11y ago
    Look up horizontal transfer. https://en.wikipedia.org/wiki/Horizontal_gene_transfer https://en.wikipedia.org/wiki/Horizontal_gene_transfer
- tstactplsignore 11y ago
  The sense I have from working in environmental microbiology is absolutely not. There simply isn't that strong of a selective pressure for the degradation of plastics, especially because (a) plastics are incredibly rare compared to other microbial food sources, even in "plastic rich" places like the pacific garbage patch, and (b) it isn't clear that there is any energy advantage for producing this enzyme in most environments- I'm not even sure the end products of the reaction are used in energy production or assimilation at all. Thirdly, even if plastics were abundant and this pathway did provide a useful source of energy, it is almost certainly not as energy efficient as the common enormously successful microbial pathways for energy production and catabolism that exist when their reactants are in high abundance. Fourthly, I'm fairly sure the reaction rate is slow enough that degradation of macroscale plastics would only occur in concentrated bacterial cultures or when exposed to concentrated stock enzyme. Your iPhone case would never be at risk- I also highly, highly doubt that macroscale degradation could occur due to naturally produced enzyme alone even in soil and ocean environments, where there is rich microbial life. Fifthly, because it is a naturally occurring degradation pathway, if there were any significant evolutionary advantages these gene products would already be widespread in the microbial ocean or soil environments. Essentially, I am almost certain that the risk of using concentrated enzyme to remove micro or milli scale environmental plastics, or even seeding local sites with cultures producing this enzyme, are 0. In reality, I don't think that there would be many plans to use this outside of bioreactors, and best case scenario it could clean up local environmental microplastics!
- ktRolster 11y ago
  > I guess then we would have to put some antibacterial in plastics too. Maybe. It's not like plastic products have a particularly long lifetime anyway, there are plenty of things that degrade them (like sun). So as long as the bacteria doesn't act super-quickly, I think we'll be ok.

x5n1 11y ago

Well if these genes exist somewhere, and we commercialize them. Is it not a matter of time until these genes become more common in bacteria in general and then we can no longer use plastics, I guess then we would have to put some antibacterial in plastics too. Like say a long time period.

forgotmysn 11y ago
I'm not a biologist, but I don't think genes are contagious
- mr_overalls 11y ago
  If they confer a selective advantage, they can quickly spread through a population: https://en.wikipedia.org/wiki/Selective_sweep https://en.wikipedia.org/wiki/Selective_sweep
- x5n1 11y ago
  Look up horizontal transfer. https://en.wikipedia.org/wiki/Horizontal_gene_transfer https://en.wikipedia.org/wiki/Horizontal_gene_transfer
tstactplsignore 11y ago
The sense I have from working in environmental microbiology is absolutely not. There simply isn't that strong of a selective pressure for the degradation of plastics, especially because (a) plastics are incredibly rare compared to other microbial food sources, even in "plastic rich" places like the pacific garbage patch, and (b) it isn't clear that there is any energy advantage for producing this enzyme in most environments- I'm not even sure the end products of the reaction are used in energy production or assimilation at all. Thirdly, even if plastics were abundant and this pathway did provide a useful source of energy, it is almost certainly not as energy efficient as the common enormously successful microbial pathways for energy production and catabolism that exist when their reactants are in high abundance. Fourthly, I'm fairly sure the reaction rate is slow enough that degradation of macroscale plastics would only occur in concentrated bacterial cultures or when exposed to concentrated stock enzyme. Your iPhone case would never be at risk- I also highly, highly doubt that macroscale degradation could occur due to naturally produced enzyme alone even in soil and ocean environments, where there is rich microbial life. Fifthly, because it is a naturally occurring degradation pathway, if there were any significant evolutionary advantages these gene products would already be widespread in the microbial ocean or soil environments. Essentially, I am almost certain that the risk of using concentrated enzyme to remove micro or milli scale environmental plastics, or even seeding local sites with cultures producing this enzyme, are 0. In reality, I don't think that there would be many plans to use this outside of bioreactors, and best case scenario it could clean up local environmental microplastics!
ktRolster 11y ago
> I guess then we would have to put some antibacterial in plastics too. Maybe. It's not like plastic products have a particularly long lifetime anyway, there are plenty of things that degrade them (like sun). So as long as the bacteria doesn't act super-quickly, I think we'll be ok.