Ideas for ammonia-based life

Microbe Stage
The microbe stage should mainly be the same, except the timescale will be longer, perhaps. While ammonia is flammable in oxygen in reality, it would be a bad idea if everything burst into flames because you (or even the AI) upgraded your cell to photosynthesis.
Awakening Stage
It may be possible for an underammonia civilization to obtain metals by distilling them from the ocean.
Does anyone else have ideas?

Do you have any scientific references to ammonia-based life being plausible?
It looks like wikipedia has some stuff on this:

Before checking that page I had only heard about silicon based life being a plausible alternative to carbon.

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speaking of xenobiochemistry; here are some stuff i’ve found previously.

and:

http://arcana.wikidot.com/alien-biochemistry

the bottom link talks about some interesting topics rarely discussed: heres one example


Amino acids are the building blocks of protein and enzymes.

  • 20 different amino acids, in various sequences, define almost every protein on Earth.
  • However, a large number of other amino acids exist in addition to those twenty, but occur relatively rarely in our biosphere.
  • Theoretically, other amino acids might exist in the universe that have not been documented on Earth.

Given those latter facts, Alien life might be based on different amino acids than terrestrial life. Organisms based on a slightly different mix of amino acids might have tissues chemically dissimilar to our own, and have properties distinct from those of earth life. They may have increased or diminished tolerances to temperatures, chemicals, pressures, etc. These alternate versions of the amino acids don’t particularly require any specific conditions on the other planet. Even an otherwise fairly earth-like planet could have life focused on a different subset of amino acids, and thus use very different proteins than those seen on earth.

Going one step further (and this is where it gets interesting) the Chirality of those amino acids could be reversed as well (or instead). Basically, this would mean a mirrored or inverted structure to how the amino acids are constructed, sort of a subatomic analogy to the difference between your left and right hand. The particular chirality arrangement common in amino acids here on earth is often called “left-handed” amino acids, and the arrangement common in sugars (cellular fuel) is “right-handed”. With the inverse, “right handed” amino acids and “left-handed” sugars, you’d end up with life that couldn’t interact biochemically with ours, and would be biologically incompatible with our own.

Among other effects, it would mean that such life couldn’t derive nourishment from earth foods, and we can’t digest foods native to their planet, either. Eating chiraly-mirrrored food would be like eating plastic, you could starve to death with a full stomach. This would also prevent crossbreeding or hybridization between the species, and even splicing genes via genetic engineering would likely be doomed to failure. The incompatibility could be far worse than this however, as laboratory tests have shown that some right-handed amino acids are actually toxic to plants and bacteria on earth. On the plus side this makes it unlikely for a virus or bacteria to be able to jump species and affect life from both worlds - though there are a few extremely simple Archaea here on earth that seem able to handle right-handed or mixed aminos, so that assumption is far from guaranteed.

Amino Acids have been found in meteorites and the tail of at least one comet, suggesting that the source and cause of life is likely to be found in abiogenesis, exogenesis or panspermia theories. However, the amino acids found in meteorites do not always have the same chirality as those here on earth. Currently, no one really knows why life on Earth chose for left-handed amino acids and right-handed sugars. One evidentiary link is water - meteorites with ice / water content tend to have mostly left-handed amino acids. Meteorites that appear to have never had any water content tend to have a mix of right- and left-handed versions. When both left-handed and right-handed amino acids are dissolved in solution, the right-handed ones tend to break down. Other proposed mechanisms for the dominance of left-handed amino acids on earth include the nature of the weak force, and the direction of the orbital spin of our planet and solar system.

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Thanks for the links, Deathpacitoast. I found this page particularly interesting, as it gives examples of Earth life that exploits unusual chemistry. That Pitch Lake is a peculiar place!

This insect uses electricity! Life is amazing.

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