> Hemoglycin (previously termed hemolithin) is a space polymer that is the first polymer of _amino acids_ found in meteorites.
I’m done, have a great day! (Monomers)
Edit: My apologies for being dismissive. I’d like to get into the specifics of why amino acids (amino and carboxylic groups specifically) are special, and interesting exceptions like hydroxy and alpha-hydroxy acids, but I’ve got to get to work and I could spend an entire year explaining the nuances. The deeper you get into the details, the more the anthropic principle rears its ugly head.
https://en.wikipedia.org/wiki/Hemoglycin