Quick Facts:
- 22nd genetically encoded amino acid
- α-amino acid not present in humans
- Abundant in methanogenic archaea and bacterium
- Anaerobic microorganisms
- Reduce carbon dioxide and hydrogen gas to methane
- Relevant in energy conservation
- Works to bind, activate, and orient methylamines during protein synthesis
- Present in the last universal common ancestor (3 billion years ago)
- Only persisted in organisms that use methyalmines as energy sources
Synthesis:
- Synthesized from two molecules of L-lysine
- Encoded by mRNA in the UAG region
- Normally an “amber” stop codon
Lysine:
Pyrrolysine: