Title:
Building-to-understand: artificial vs. biological proteins

Abstract:
Nature has explored only a tiny part of all possible sequences that can be constructed from the canonical amino acid alphabet. Our group explores the structure/function potential of the artificial protein sequences to examine whether the biological structural repertoire is a biophysical consequence of the amino acid pool or whether it represents a bias created by evolutionary adaptation. It has been assumed that existing proteins adopt specific folds because natural selection has evolved rare sequences with such ability, while it was implied that unevolved sequences would likely be mostly disordered and probably toxic to life. However, our recent results are not completely supportive of these hypotheses and suggest that random protein sequences (especially if they are highly disordered in structure) can be good progenitors for evolution of specific structure/function.