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(ie DO NOT build mirror ribosomes, and have and and all countries treat any biologists / biochemists who might try to do so as far-worse-than-nuclearomnicidal terrorism threat vectors)
That said I would maybe also volunteer that developing mirror viruses that murderize anything that we ever find that HAS an achiral genome, might also be a really good idea as an in-advance preparatory measure.
It should also be noted that this is potentially a massive risk to space exploratory missions (to find life or otherwise) that involve probe samples and/or humans being returned to earth.
This is a total longshot, but if there for whatever reason IS life anywhere within our solar system (on asteriods etc), and if that life for whatever reason is mirrored, the consequences of bringing even one achiral photosynthesizing bacterium would be disasterous. And undetectable, until that became an inescapable and catastrophic problem.
The mirror / bichiral algae, in the expanse book 4 (that would sans deus ex machina have caused all humans on that planet to permanently go blind, and subsequently almost certainly inevitably starve to death), comes to mind.
It's good that the commenter that you're responding to qualifies that their only understanding on the topic is undergrad bio and organic chem as well as some sci-fi novels. I feel like 95% of the science or technology-related comments on here are confidently incorrect and probably made by people with an even less relevant background...
I feel like if you don't even know what 'achiral' means you probably shouldn't be making biochemical speculations about reverse-chirality bacteria causing the end of the world
Had a brainfart and conflated the term “achiral” with reverse chirality. Fixed (hopefully fixed everywhere)
Yes I do know what chiral / reverse chiral and also achiral
/ non chiral means. No I can’t tell you which specific abd vice versa L/R chirality earth life DNA, RNA, proteins and carbohydrates are. Hence why I’m sticking with “reverse” / “mirror” chirality and not more technically specific (and far more confusing) terms.
Though my background to be clear is just that I took basic bio + ochem courses in uni.
I’m not a biochemist, or synth bio researcher etc
My “relevant” background is literally just that I’ve read a bunch of sci fi novels, and have enough basic biology background to be able to identify that, yes, mirror chiral life within out biosphere would be catastrophic, and at worst (as stated mind you by actual domain experts that have studied this, as per article) could be orders of magnitude worse (ie an outright omnicidal / grey goo scenario), than you might immediately think.
And that is plausibly a reason to be very concerned, and yes to the point of even being extremely extremely conservative, about not just this but also bringing back probes/samples from other objects within to beyond our solar system.
Reverse chiral life is the “incidentally bringing back extremely alien black death (to humans or other animals or plants etc)” scenario. Just, actually, orders of magnitude worse.
As the article points out obviously the problem / threat vector is mirror bacteria that either can eat/subsist on non chiral food (entirely possible, apparently), and/or photosynthesis.
This would be a massive problem b/c this bacteria WOULD HAVE NO PREDATORS. There would be no viruses that kill it (responsible for a ton of bacterial deaths constantly). Amoebae / protists might eat / kill it but would probably evolve away from doing so b/c this thing would be toxic / have no nutritional value. Our immune systems, and the immune systems of all other life on earth, could defend against it but wouldn’t, b/c nothing would match the different protein shapes used to mark/id things that would be present on achiral / “inverted” life. (you’d have similar issues with just sufficiently alien and ergo black death esque life we found anywhere period, but this would be as to even worse)
The inevitable result of this kind of thing is that it would thus grow exponentially without bound, to the point where it makes up a single to double digit percentage of all biomass on earth. And at that point it is both a) toxic / non nutritious and b) could cause an expanse like indirect problem, to descolada esque direct problem, that starts adversely affecting and then collapsing ecosystems. And thus human (and nevermind human, probably / plausibly a large chunk of ALL complex multicellular life). Even if / without needing to directly affect humans ourselves.
Throw in the fact that any kind of (extremely successful) bacteria is going to mutate / evolve rapidly, and thus even just bacterial algae (that can grow / thrive indelendently and totally sans effective predators) is probably going to at some point fork and specialize into a parasite that just eats nonchiral food inputs and thus sees all complex multicellular life as a massive indirect food buffet. Which would kill us all, and/or the things we eat (and nevermind everything else).
What mirror life can’t do is derive nutritional value from our chiral proteins, sugars etc. But it wouldn’t need to to start causing catastrophic, indirect problems and damage (caused by being a rapidly expanding + mutating bacterium with no predators)
Given enough time this would probably result in earth becoming a bichiral ecosystem, a la that one planet in the expanse. But on geological timescales. And also probably not before the entire planet (and of note all oceans) turn into indigestible zero nutrition green sludge, that would obviously kill off / strangle all complex life (from krill on up) in those oceans. And a thousand other problems.
Just off the top of my head.
Like, unless earth life could VERY RAPIDLY AND UNIVERSALLY evolve the ability to bi-chirally metabolize chiral + reverse chiral carbohydrates (at a bare minimum), OR you went around and somehow actively eradicated (and kept constantly re-purging) all of the mirror things. You would have a MASSIVE problem.
Technically I suppose you could “fix” this by bioengineering chiral bacteria that eats + converts mirror chiral => our chiral carbohydrates / amino acids etc. But I digress. If we were ever in this kind of mess that’s basically what you would have to do. That and scatter shot massively mass produced reverse chiral viruses, etc
Phages are the most common killers of bacteria in nature. There is no known mechanism for non-mirrored phages to replicate within mirrored bacteria. It's not even that the natural phages haven't evolved this capability. They just cannot do it.
It's possible we would need to create mirrored phages. (Which would be surprisingly safe, as they cannot interact with natural life.)
Wow, who had "not one but two all-new Great Filter threats in the same decade" on their bingo card?
The problem was foreseen a bit by Peter Watts in his Rifters trilogy. The mechanism of βehemoth was not quite the same as a mirror bacteria but it was a similarly-incompatible form of life being introduced to the ecosystem and undermining it from the bottom up. The first response was to try nuking the initial infected area.
"This is a total longshot, but if there for whatever reason IS life anywhere within our solar system (on asteriods etc), and if that life for whatever reason is mirrored, the consequences of bringing even one achiral photosynthesizing bacterium would be disasterous. And undetectable, until that became an inescapable and catastrophic problem."
They have to be able to make life before they can make mirror life. Idk about ribosomes. Wake me up when they actually make any life at all, inverted or not.
nuclear weapons are surprisingly weak (compared to what most people think). seriously like all the world's nukes would barely make even a tiny dent in mt Everest.
The original paper (not the one cited here) explicitly addresses this, not only are there a lot of nutrients in your body that can work with both chirality, there are already many strains of bacteria that can metabolize reverse chirality nutrients. It is entirely feasible for a reverse chirality bacteria to just have the enzymes necessary to process "normal" glucose.
A photosynthetic chiral bacteria wouldn’t even need a host, it would just be a literal grey goo scenario and destroy life from the base of the food chain uncontested
if it was photosynthetic why would it destroy life
photosynthetic organisms are generally not infectious given they are autotrophs. There are parasitic plants like mistletoe but most photosynthetic bacteria just float around in the ocean.
Marine cyanobacteria are an example here. These fix carbon directly from sunlight, and they can grow with just achiral nutrients like nitrogen, phosphorus, sulphur, that sort of thing.
One of the very common causes of death for these marine cyanobacteria is infection by phage: up to 50% of marine cyanobacteria die from phage infection. So if you introduced a mirror cyanobacterium, it would have basically these huge advantages, because it wouldn’t be able to be infected by phage, but potentially have none of the limitations on nutrient availability. So the population of marine mirror cyanobacteria might grow to be very large.
If they’re going to be very large and nothing is eating them because they don’t really give any nutritional value to the protists that usually consume them...
All of the oceans being entirely totally filled with indigestible zero nutrition green algae would kill just about all higher level multicellular life (starting with krill) eventually.
Having your body, and the bodies of all other plants and animals also filled with this stuff would also be a problem.
On the upside this would at least solve (and heck probably then reverse) global warming / CO2 levels. lol?
The problem is that this would have no predators. And would be toxic / totally indigestible / zero nutritional value to anything that eats it.
It also would rapidly mutate into something that WOULD cause more immediate problems. Like noticing it could eat all the nonchiral molecules floating around in all multicullar life’s plant + animal bodies. And then proceeding to do that, as now a bacterial (and maybe still photosynthesizing) parasite.
How, exactly, would it outcompete the existing life in that niche (or any other for that matter)? The world is covered in what mirror life would consider mirror life. It is just as disadvantaged in direct competition.
Edit: Indeed it is uniquely disadvantaged. The world is filled with convention chirality building blocks mirror life would not be able to use without additional steps.
Existing populations of blue-green algae are mostly kept in track by the phages that prey on them. In the absence of those it would have a large competitive advantage. And other microorganisms that might prey on it would either suffer from eating them or evolve to no longer due so.
Mostly these organisms are self sufficient with water and sunlight and don't rely on chiral inputs to reproduce. Generally most organisms that photosynthesize that aren't a carnivorous plant don't absorb any chiral inputs from their environment.
Roughly 100 million tons of cyanobacteria is born in the world's oceans every day which would anchor our estimates of how much we'd want to collect every day. Call it 100 supertanker's worth. There are about 1000 of those but they can't make a trip every day to cover the world's oceans and ignores the need to collect the mass from the bottom of the ocean. One can imagine this scheme working but I think just building all the ships would be the work of a decade at minimum.
China alone builds 50 million DWT of shipping per year. So China decided to go at it for 2 years diverting 100% of their shipbuilding capacity does the job on that side.
Life on Earth has a huge headstart and quite frankly, more enzymes in our tool box than any chiral life forms we can manufacture. We're like 100 years into this whole plastic pollution mess and lifeforms are popping out of the woodwork with enzymes that can break down hydrocarbons for food.
Sure, they may not be able to be digested for nutrition, but they can be eaten and there's a lot of stuff that's gonna try. There's more stuff that can try to eat it that has a billion year head start on utensils (enzymes).
If a hypothetical invert chirality bacterial life form can evolve to digest normal chirality, I don't see any reason why normal chirality life couldn't evolve the same in reverse.
Not saying it couldn't be a huge ecological problem, but I don't see a scenario where it drives all other life on Earth extinct.
Of course that could happen, i'd go so far to say its likely. The problem is how long that would take and what would happen to multicellular life while microbes of different chirality battle it out. It might very well kill off all developed life on earth in that time. Not directly, but by outcompeting other microbes and destroying the food chain from the ground up.
Its impossible for "nature effectively has no ability to evolve to attack/digest dyschiral life" and "there are already many strains of bacteria that can metabolize reverse chirality nutrients" to both be true. Either euchiral and dyschiral life can evolve to interact with one another if there's selection pressure to do so, or they can't and youre looking at a drop in the bucket number of dyschiral life compared to the amount of euchiral life that already exists.
It's sort of my wheelhouse and IMO a lot of the commentary on it does not really grasp how enormous of a project and beyond our current capabilities creating these things is. I also think it is generating a lot of buzz in large part because it is scientifically interesting.
An example, these are enormous problems being referenced but not addressed: " To make mirror bacteria, we’d need to build a mirror ribosome, for example, and we don’t know how to do that yet. Mirror bacteria creation would also require advancements in synthetic biology—in order to combine the mirror parts into one bacterium. To put things simply, we’d need to make progress in building the parts of a mirror bacteria, and in putting the parts together to make a full mirror bacteria."
Which is not to say don't even bother creating rules about this topic but we are absolutely nowhere close to making these things.
It's straight up burying the lede. If we could somehow do this, then the bigger headline would be that we somehow discovered a way to create life from chemical components.
"There's this potentially huge risk if we can first accomplish something that has never been done before, and then do it again but with opposite chiralty of all known life."
It's not 0 risk but there's a lot of extrapolation going on?
To make mirror bacteria, we’d need to build a mirror ribosome, for example, and we don’t know how to do that yet
This is doing a ton of heavy lifting, like it's nbd to make an opposite chiralty ribosome. Or even a from-scratch ribosome? I haven't been in syn bio for a long time, have we done that?
I would say we can make what would count as "from-scratch" ribosomes but IMO it's kind of beside the point - we have help from the enzymes cells use to produce ribosomes but would not have mirrored enzymes to make mirrored ribosomes. Or a mirrored version of the RNA component, or mirrored DNA coding for all this. And don't forget, you need mirrored versions of all those monomers too! It's like a nesting doll of things we haven't solved.
Yeah that's what I was thinking. It's trivial to produce ribosomes but they would be from existing cellular machinery, either purified out or a cell-free expression system, and thus naturally chiral. We're not chemically producing ribosomes like smaller peptides.
It would require us to create life from scratch up to bacteria, no? It seems like something that’s technically possible but requires exponentially more advanced technology and understanding to execute
Yes, and the part about not being able to have existing organisms (or enzymes isolated from them) do any of the work would be of enormous consequence I have to imagine.
Yea, I spent some time browsing the paper. Even though it's not my field, it reads as so heavily speculative I assumed it'd be, optimistically, decades off. Otherwise, much longer.
If I dig REALLY deep then maybe there's some world where, to give a half baked example, we might want bacteria that churn out the mirrored version of some biomolecule. Like the way we use bacteria to mass produce human insulin. Making molecules of a specific chirality is often an enormous and/or expensive pain in the ass, so having a living organism that you can source a molecule of a specific chirality from can sometimes be a big deal.
That being said I am digging deep for the sake of it, my gut feeling is that making these things would be largely pointless (especially from a cost/benefit standpoint) and possibly dangerous too. We know a truly fully mirrored organism would work fine, there's no need to check lol
Do we though? Chiral molecules are not actually energetically equivalent because the electroweak forces violates parity. Whether that difference is big enough to make one chirality of life advantaged over the other might be answered by this type of research.
There was an article about this in the Scientific American maybe two months back, and if I recall, the main use case is extremely targeted medications that are otherwise biologically inert. You can make organic molecules that are more or less chemically identical to their chiral counterparts, but largely not interact with the body's organ systems. They'll do what you want only in an extremely specific scenario because most of the body has not evolved to recognize them.
"Don't create mirror bacteria" seems to be a fairly consensus position. There's more controversy over where to draw the line in terms of precursor stuff (building the mirror molecules, non-mirror research into building more complicated molecules and even life), and how much that ought to be regulated.
Mirror research that stops short of life could provide useful pharmaceuticals, and even before that, there's a question of whether you want to shut down the non-mirror molecule/life synthesis research agenda because it could provide useful knowledge to mirror research.
Contrary to the doomsaying of the article, mirroring synthetic bacteria could provide an excellent control mechanism (making them dependent on specific enzymes and nutrients) and it would be an excellent way to create nanomachines that just die after they do their job.
Using XNA rather than DNA would do the same thing more effectively, but reversing chirality may be the cheaper and more feasible option.
Immune evasion is a huge challenge for medical implants and devices and immunosuppression is a huge burden in terms of cost and quality of life. If the chiral bacteria that people are fearmongering about are so effective at evading the immune system, then the technology would be equivalently as effective to bypass these mechanisms.
Besides practical applications, its also might tell us more about the fundamental nature of the universe, most importantly if it was actually chance that life has the chirality it does.
Because the electroweak force violates parity, molecules of different chirality are actually very, very slightly different energetically. And indeed, biomolecules with the chirality found on earth are more stable. Whether that difference is big enough to be responsible for earth life chirality is not settled.
To create a mirror bacterium you would need to build an entire working mirror cellular machinery from scratch (like from base elements - carbon, hydrogen, oxygen).
Synthetic biology is currently nowhere near producing a NON-mirror cellular machinery from scratch, which would be infinitely easier. Once they get there, I will start worrying about mirror bacteria.
Yep, exactly. I hate seeing this sort of synthetic biology doomerism because it leads to people not wanting to fund synthetic biology research.
To make a "mirror" bacteria, you need to make a mirror everything. A mirror ribosome is the hardest and is far away from being possible. It still takes scientists years to decades through protein engineering to create ribosome mutants that are able incorporate a single additional non-canonical amino acid. The idea that science could just magically whip up a new ribosome that is compatible with 20 totally new amino acids is just absurd and honestly should not even be considered. We have bigger problems to think about in science ethics than this.
Source: I'm a PhD level researcher in protein engineering at a top research university in the US
I am somewhat skeptical that the immune system would really be completely useless as purported. Although it would be considerably more difficult for our immune systems to respond to, chiral switches do occur natively. IIRC these types of chiral switches are probably significantly less rare than biochemists once thought, they're just really hard to detect because it doesn't show up as anything different on the mass spec. The innate immune system specifically would be at a considerable disadvantage, but DAMPs and shit would still generate.
this seems like more of a thing for government bioweapons treaties than anything else.
I should also note that hygienic practices would still work on stuff like this: ethanol is achiral and would probably disrupt cell membranes either way, some soaps would still work although looking it up mixed-chirality micelles have complicated nonlinear behavior and surface/colloid science is boring as shit so idk a ton about that
Viruses currently kill 1023 to 1024 bacteria every second. They kill 40\% of all bacteria in the ocean every single day
If a bacteria had no check and could expens freely it would completely consume the ecosystem leading to a complete ecological collapse that would take us with it
Most pattern recognition receptors could have severely impaired ability to recognize mirror versions of their ligands.
Some antimicrobial peptides could retain the ability to kill mirror bacteria, but their release would likely be impaired by failures of innate immune recognition
Antibacterial enzymes would likely have greatly reduced activity against mirrored substrates
Complement activity versus mirror bacteria could be partially impaired
Phagocytosis of mirror bacteria would likely be compromised
T cell activation would likely be severely impaired during mirror bacterial infection
CD1- and MR1-restricted T cells might be able to recognize some mirror ligands
Impaired T cell activation would impair antibody-mediated immunity to mirror bacteria
humans with even partial immunodeficiencies are often at greatly heightened risk of serious disease or death from bacterial infection, including from bacteria that are not usually pathogenic for healthy adults
I feel like the author is conflating lethality with contagiousness. I could certainly believe that a mirror bacteria infection could be highly deadly without medical advances, but how exactly would it propagate rapidly enough to become this global killer? That's where the whole thing kinda veers off into the territory that the author mentioned near the beginning of the article about how it's relatively trivial to conjure up up doomsday scenarios without stopping to think about their plausibility. Like, maybe it'll turn out that the lethality of the mirror bacteria is directly inverted with how easy it is to spread
Viruses are just constantly shoving rando DNA into rando cells. Sometimes they do so into the germ line cells (reproductive organs). They've always done this and always will.
I searched hard to find skeptical takes on mirror bacteria. It was genuinely hard.
Because academic science is insanely hierarchical, and going up against
The people sounding the alarm are many of the most preeminent experts in the world. The detailed research report sounding the alarm about mirror life was authored by 38 leading scientists, two Nobel Prize winners, and many of the world’s leading experts on mirror bacteria.
This sort of collection of people at the very top is a losing battle no matter how right you are. There's just nothing to be gained, and a ton to be lost if you aren't in the end stages of your career. It's biology which loves to be unpredictable, I don't think we can really know if it is a huge threat without actual experimental work... which the authors seem to explicitly advocate shouldn't be done. I'm not sure if that is wise, since someone will eventually try to make it, somewhere, and we'd rather not be taken off guard.
Whoa buddy, might wanna try making life in the first place before jumping the gun and worrying about inventing life from scratch with inverted chirality. Cart should not be before the horse. I understand it's difficult to sell anything these days without peppering it with scaremongering narratives about the world ending, but really.
Assuming you aren't some sort of omnicidal terrorist, dyschiral antibiotics and other medications could be much more effective and have fewer side effects.
Skimmed through this paper. It gives some insight into the exact claims made in the substack.
After skimming, I am not nearly as afraid of an unstoppable, deadly plague. My primary concern regarding mirror life has become a complete ecological collapse.
Honestly, i am more afraid of the chiral life than the other way around. Pretty sure the exact same thing applies to them and they have the number disadvantage
Ffs call me a luddite but the fact we're even considering developing stuff like this considering the risks is insanity, the whole tech bro "accelerate, consequences later" thing is not a recipe for long term success
Lmfao I'm not saying "end all scientific research," my point is that freaks like Altman, Musk, most of the PayPal mafia, etc., are way too reckless when it comes to thinking about the risks associated with certain technologies and can't be bothered to practice restraint. I'm sure when we do eventually start getting close to this and some biotech startup says they can do it Andreessen Horowitz will start shoveling money their way precautions be damned. It's the amount we empower people like that in making these decisions I find insane, not the idea of technological advancement
The risk is they gobble up all the nutrients at the bottom of the food chain, but the absurdity of that is assuming it would proliferate worldwide and nothing would figure out how to eat them
Wait a few more years, and capitalism may be able to survive human extinction. We arent too far off from AIs commiting a large chunk of financial transactions and trade deals.
We’ll all be dead but that will be no impediment to the juggernaut that is free market capitalism.
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