Comment by dekhn

People have been making grand statements about the structure of the protein universe for quite some time (I've seen a fair number of papers on this, such as https://faseb.onlinelibrary.wiley.com/doi/abs/10.1096/fasebj... and https://faseb.onlinelibrary.wiley.com/doi/abs/10.1096/fasebj... from a previous collaborator of mine).

Google didn't solve the structure of the protein universe (thank you for saying that). But the idea of the protein structure universe is fairly simple- it's a latent space that allows for direct movement over what is presumably the rules of protein structures along orthogonal directions. It would encompass all the "rules" in a fairly compact and elegant way. Presumably, superfamilies would automagically cluster in this space, and proteins in different superfamilies would not.