I'm really kicking myself for saying "a few" genes are shared between archaea & bacteria.
> The proteins that archaea, bacteria and eukaryotes share form a common core of cell function, relating mostly to transcription, translation, and nucleotide metabolism.https://en.wikipedia.org/wiki/Archaea#Genetics
It's really more like hundreds or thousands of genes. And they're around the foundations of translating DNA to RNA and RNA to amino-acid chains.
And we share the genes that are related to DNA maintenance and translating DNA to proteins.
The idea is that, without these shared genes, horizontal gene transfer doesn't even make sense. There would be no shared genetic code. The nucleotides used might not even be the same. Amino-acids have right-handed chirality (which is probably related to our DNA having left-handed chirality). If life independently evolved it would probably use amino acids and nucleotides, but there's no guarantee that the handedness would be the same, or that the genetic code would be the same.
> The proteins that archaea, bacteria and eukaryotes share form a common core of cell function, relating mostly to transcription, translation, and nucleotide metabolism. https://en.wikipedia.org/wiki/Archaea#Genetics
It's really more like hundreds or thousands of genes. And they're around the foundations of translating DNA to RNA and RNA to amino-acid chains.
And we share the genes that are related to DNA maintenance and translating DNA to proteins.
The idea is that, without these shared genes, horizontal gene transfer doesn't even make sense. There would be no shared genetic code. The nucleotides used might not even be the same. Amino-acids have right-handed chirality (which is probably related to our DNA having left-handed chirality). If life independently evolved it would probably use amino acids and nucleotides, but there's no guarantee that the handedness would be the same, or that the genetic code would be the same.