Rumraket
July 24, 2022, 6:24pm
74
Giltil:
This is probably not the case for the folds. Is there any evidence that a given fold such as, say, the immunoglobulin fold, can evolve by combining functional sub fragments?
You should watch this lecture:
The late protein biochemist Dan Tawfik(died recently in a mountain climbing accident) did this extremely interesting lecture back in 2020, on his research group’s work on very early protein evolution:
[Structural Biology | D2S4 12/21 Protein Evolution – From So Simple a Beginning - Dan Tawfik]
Highly worth watching for anyone else interested in this subject of protein evolution. And highly relevant to the question of the origin of enzymes.
He talks about attempts to reconstruct the earliest stages in the emergence of enzymes from short peptide sequences, what functions they might have had before they worked as catalysts, how they assemble into larger tertiary and quaternary structures, and later evolved into more complex and folding protein structures with bona fide enzymatic activities.
Of particular interest (at least to me) is what he says starting at about 13:48, where he explains how phosphate binding seems to have evolved about 300 times independently in the histor…
There is a considerable literature now on fold-evolution and the many different connections between known protein folds.
While I don’t know whether the IG itself owes it’s origin to such a process(haven’t looked into it), the IG fold has itself lend fragments to the emergence of other protein folds:
Author summary Judged by sequence and structure, about 2,500 different protein evolutionary lineages have been identified to date. Since proteins are central to life, understanding where they came from and how they continue to change is a key...
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