4 ms·

Yes and it still doesn't quite explain things clearly. Mercury is an element so even if it gets broken down into other forms that are less toxic, isn't it still

• mint2 4y ago
  Organometallic mercury compounds are extremely toxic, so it seems the enzyme is converting the mercury to some inorganic salt with low bioavailability but yeah it appears it becomes less bioavailable but not much else is stated. It’s not removed so I have the same question you do about the possibility of another natural reaction coming along and converting it back
  • kurthr 4y ago
    Methyl Mercury is one of the most dangerous forms, because it is volatile and easily absorbed (while liquid metallic mercury is relatively benign). One possibility for the fungus is phenol compounds. They are commonly used by plants to inhibit fungus so the ability to excrete/them would be generically useful to a fungus. Also, mercury phenols are notably quite stable.
    • pfdietz 4y ago
      And dimethyl mercury is even worse. There's a famous case of a chemist at Dartmouth who died horribly from a single droplet that permeated through a nitrile glove.
      • pfdietz 4y ago
        Link: https://www.science.org/content/article/mercury-poisoning-kills-lab-chemist https://www.science.org/content/article/mercury-poisoning-ki...
  • idontwantthis 4y ago
    If it’s concentrated in the fungus instead of dispersed in the soil, that sounds easier to remove, process and store/recycle.
    • Jolter 4y ago
      Have you ever tried to remove a fungus from soil? I think it would require machinery to dig up the whole field, process the soil and spit it out - which I think is no less expensive than using traditional chemical methods for binding the mercury in stable compounds.
  • matkoniecz 4y ago
    > so I have the same question you do about the possibility of another natural reaction coming along and converting it back Was it outcome of that compound being eaten by fungus? (some process that resulted in energy extraction?) In such case reverse strategy is possible but less likely
• thaumasiotes 4y ago
  > Mercury is an element so even if it gets broken down into other forms that are less toxic, isn't it still present and not "cleared" as the article claims? Are the new molecules less volitaile/unlikely to revert to their toxic organic forms or more liekly to drain off into waterways? I have zero specific knowledge, but I can talk about the kind of thing that's generally happening with poisons. Mercury is extremely toxic. That is probably because various of your enzymes respond to it as if it were a different organic chemical, and use it as a building block in important molecules that they are responsible for building. (It might also be because mercury naturally reacts with important molecules, expelling important functional parts and taking their place. In either case, you're left with defective functional molecules that have useless mercury where they were supposed to have something important.) Since mercury is an element, it can't be broken down into other forms. But it can be used to build compounds that include mercury atoms. You then have the question of whether these compounds are toxic in the same way that elemental mercury is, whether because they are still (wrongly) recognized as a substitute for something else, or because they still react with proteins to replace important parts of the proteins with mercury atoms, or because the compounds react with something else in the body in a way that ejects their mercury atoms (leaving those atoms free to do their toxic thing). The goal would be to form mercury compounds that are (1) chemically stable, trapping the mercury atoms; and (2) biologically inert. Ideally those compounds would then either filter through the digestive tract and be excreted in feces, or they'd make their way into the bloodstream, get filtered out by the liver/kidneys, and be excreted in urine.
• jandrewrogers 4y ago
  Organic mercury compounds are extremely nasty byproducts of industry. Their badness is largely due to their high bioavailability i.e. they are readily absorbed into our tissues. Inorganic mercury salts, by contrast, tend to have very low bioavailability which limits absorption even in environments with significant background quantities. The toxicity is as much a function of bioavailability as it is presence in the environment. This fungus dramatically changes the bioavailability of mercury compounds in the environment. There are many highly toxic elements in our environment that are effectively a non-issue due to low bioavailability. In one end and out the other with minimal absorption.
  • fergal 4y ago
    Thank you for providing the relevant background science.