there is currently ~no risk because generating mirror life is such a monumental task. we dont have a full biological bootstrap sequence currently. even syn1.0 which was a synthetic genome transplant and rebooting operation, required a living host cell to transplant the DNA into, and the genomic dna does go from a computer file, but only the smallest ~100 bp fragments are made by robots and chemistry; intermediate fragments are assembled and amplified in enzyme reactions, bacteria, and yeast.
in principle you could get these to be entirely in vitro, but the yields would be nearly nil. and the expense of mirror dna monomers is... i can't even imagine. you'd probably bankrupt a midsize nation on that. and theres no motivation to decrease the cost because there's not really any other practical use for mirror dna outside of fucking around scientifically. and thats just the DNA. our ability to synthetically make proteins taps out at around 150-200 residues (maybe 2-4x that if you can get clever with native chemical ligation) and the purification and isolation at that length is truly a nightmare, not to mention refolding longer sequences is also hard.
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.
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?
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.
And surely this shouldn't be a difficult question to answer, right? Put an autotroph (the simplest that we know of) in a test tube and give it a ever-stricter diet and observe how far you can go without it dying off.
if its fully autotrophic you dont need to add glucose. i think some forms of nocardia can live on m9 minus glucose.
of course anything that can live on m9 has way more genes in it just to biosynthesize the necessary amino acids and nucleic acids. That's why syn1 is a mycobacterium -- fewer genes because it has almost no metabolism. if you look at the biochemical pathways for mycobacterium its laughable how much is greyed out
- 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 them. It also means it can't attack and decompose our tissues, so it would have no way to enter our bodies.
- With only simple lipids as food, it would need to take all Nitrogen from the atmosphere or inorganic compounds, which means it can't really be a pathogen for humans (or any animals) even if it could somehow enter our organisms. However, it could live on the soil and possibly be a plant pathogen.
- It's "mirrored" toxins won't have any effect on us. (But compounds that are normally benign possibly could be toxic if "mirrored" - I can't say for sure if it's possible.)
doubly so if it’s from a person with no expertise in the relevant field
Let's agree that news and articles that are shocking, scary, but not likely to happen, aka. clickbait, are even more common than comments like mine.
The parts would be similar enough to form bonds and trigger receptors, but different enough to become permanently stuck, unable to be processed.
Most critically, metabolic pathways.
But that isn't to say there isn't already varied chirality in nature [0]. The primary reason life is generally aligned to one chirality is because its very purpose is to interoperate with the living environment around it.
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? What if it out-competed those with predators? That might be game over for life as we know it.
I'm NOT saying this would happen, just that it one of thousands of possible scenarios one can come up with that go very badly. No one can say with certainty which things would or would not happen.