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Mirror bacteria research poses significant risks, scientists warn

the-scientist.com

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Re: Mirror bacteria research poses significant risks, scientists warn

#141

Post by roywiggins »

aeternum wrote: post #130
scotty79 wrote: post #23

How much achiral food would be available for these bacteria anyways in nature? They'd have to compete for it with all other life.

Seems like some kind of achiral algae would actually be the most dangerous. People forget that blue-green algae caused a global climate apocalypse, polluted the oceans and atmosphere with deadly oxygen, caused all exposed iron to rust massively changing ocean chemistry, and threw the entire globe into an ice-age that lasted 300 million years. I wonder how we would stop something like that. It'd be like the algae bloo…

The report goes into a green goo scenario, a photosynthetic mirror bacterium eating the bottom of the oceanic food web and sending stuff up the chain extinct. One scenario that they deem less likely is it sucking enough co2 out of the atmosphere to doom us to an ice age, though they couldn't rule it out.

Re: Mirror bacteria research poses significant risks, scientists warn

#142

Post by roywiggins »

throwawaymaths wrote: post #64
ninininino wrote: post #61

Earlier quoted context omitted.

I don't think anyone is worried about mirror proteins by themselves, they are worried about someone assembling a self-replicating/self-propagating mirror life, no? In which case, the fear is that you can't just run around ozone-ing every little colony of chiral-mirror version of cyanobacteria under every rock in remote Siberia or wherever.

1. > Should work be started on developing mirror immune system cells, just in case? 2. by way of direct response to your question. mirror nutrients (like scavenged AAs, even for autotrophs) are liable to be very scarce so they'll have one hell of a disadvantage makimg it on this world.

Not if you engineer your mirror bacterium to eat normal nutrients to get them started. Or they scavenge enough non-chiral molecules to eat that they get the opportunity to evolve the capability on their own.

Re: Mirror bacteria research poses significant risks, scientists warn

#143

Post by [deleted] »

roywiggins wrote: post #141
aeternum wrote: post #130

Earlier quoted context omitted.

Seems like some kind of achiral algae would actually be the most dangerous. People forget that blue-green algae caused a global climate apocalypse, polluted the oceans and atmosphere with deadly oxygen, caused all exposed iron to rust massively changing ocean chemistry, and threw the entire globe into an ice-age that lasted 300 million years. I wonder how we would stop something like that. It'd be like the algae bloo…

The report goes into a green goo scenario, a photosynthetic mirror bacterium eating the bottom of the oceanic food web and sending stuff up the chain extinct. One scenario that they deem less likely is it sucking enough co2 out of the atmosphere to doom us to an ice age, though they couldn't rule it out.

[deleted]

Re: Mirror bacteria research poses significant risks, scientists warn

#144

Post by roywiggins »

phkahler wrote: post #50
Qem wrote: post #21

Earlier quoted context omitted.

Mirror life would have no interoperability with normal life, in biochemical terms. Say, if a predator attacked a mirror bacteria, and ate it, it would be just like eating an inedible microplastic particle. A technological analogue would be to change tensions in electric outlets at random, between 115V and 230V standards, with no indication of which outlet has which tension. People would start blowing equipment left a…

>> Mirror life would have no interoperability with normal life, in biochemical terms. That sounds like a good thing but... Our food chain starts at the bottom with bacteria turning nutrients into bio-molecules right? These bacteria are eaten by other things going up the food chain ultimately to us. What if some bacteria got loose at that bottom level and started eating all the nutrients with no natural predators? Wha…

The report's scenario is a photosynthetic mirror bacterium eating the bottom out from under the oceanic food web. The existing predators would not be able to eat them, and so they would grow fast, and their predators would then shrink in population and that interaction would ripple upwards sending marine animals extinct.

Re: Mirror bacteria research poses significant risks, scientists warn

#145

Post by roywiggins »

joshuaissac wrote: post #5

Why not create mirror viruses to infect these mirror bacteria? And mirror predators to consume the mirror bacteria. Or compound microbes that can eat both mirror bacteria and regular bacteria, so that we can deploy them before we create mirror bacteria. For example, there is already a bacterium that can eat L-sugar, which is a mirror of regular sugar. https://en.wikipedia.org/wiki/L-Glucose Once the mirror creature i…

The report suggests releasing mirror phages, but they could only control the bacteria, not eliminate them. And they would likely evolve resistance so we'd have to somehow boot up an entire ecosystem of phages to keep things under control.

Re: Mirror bacteria research poses significant risks, scientists warn

#146

Post by ashoeafoot »

baranul wrote: post #139
andrewflnr wrote: post #135

Earlier quoted context omitted.

> an antibody to a correct-handed antigen would not automatically bind the mirror I wouldn't expect it to, but rather I'd expect the immune system to learn the new antigen just like it learned the old one.

Unfortunately, seems the only way to figure this out is by testing. But on the flip, nobody can really trust that it won't accidentally or purposefully escape from labs.

Thus we can conclude military will make them. And they will escape.

Re: Mirror bacteria research poses significant risks, scientists warn

#148

Post by nmstoker »

geysersam wrote: post #147

If this is such a powerful niche for an organism to be in, why haven't they already emerged naturally over the 3 billion year history of life on earth?

Life forms are effectively locked into the current set of chiral molecules. For a cell to flip, it would need all the corresponding mirror changes to happen as well, since the behaviours are interlinked - this makes it something that would be highly unlikely to occur due to evolution and why it's only realistic if carried out by people all at once.

Re: Mirror bacteria research poses significant risks, scientists warn

#149

Post by slumpt_ »

foobiekr wrote: post #119
M95D wrote: post #72

Earlier quoted context omitted.

A completely "mirrored" organism is not that dangerous. - It would still have antigenic properties, just not the ones we are familiar with, because antigens are proteins or proteins bound to sugars. Both have "left" vs "right" variants. - It can't eat any ordinary food, except simple fats. Common proteins and sugars won't fit it's enzymes. That means it can't digest sugars, proteins or any combination that contains t…

So much confidence about how this thing we’ve never encountered will not be a problem.

that’s fairly on brand for hackernews

doubly so if it’s from a person with no expertise in the relevant field

Re: Mirror bacteria research poses significant risks, scientists warn

#150

Post by jtwaleson »

notfed wrote: post #133
throwawaymaths wrote: post #64

Earlier quoted context omitted.

1. > Should work be started on developing mirror immune system cells, just in case? 2. by way of direct response to your question. mirror nutrients (like scavenged AAs, even for autotrophs) are liable to be very scarce so they'll have one hell of a disadvantage makimg it on this world.

I'm really curious to know the details here. What is the minimal set of dependencies for the simplest autotroph? Clearly there was an original self-replicating cell and it was successful, so assuming we constructed the necessary proteins, why do you think it would be difficult the second time?

This is the big question about abiogenesis. If it was easy then life in the universe could be very common. If it is exceedingly difficult, we might be alone.

What is the smallest set of molecules needed to self-replicate, and how common are the ingredients (& nutrients)? I believe all of this is completely unknown, but I havent looked into the research for years now.

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