Reposted by University of Arizona EEB
We identified protein domains in LUCA (Last Universal Common Ancestor). Their distinctive amino acid usage reveals the order amino acids were added to the genetic code, based mostly on size. Older proteins hint at earlier alternative codes. 1/15 @seekingluca.bsky.social www.pnas.org/doi/10.1073/...
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Order of amino acid recruitment into the genetic code resolved by last universal common ancestor’s protein domains | PNAS
The current “consensus” order in which amino acids were added to the genetic code
is based on potentially biased criteria, such as the absence of s...