About the Protein Space Vastness

Jorge A. Vila

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arXiv · 2008.11602

About the Protein Space Vastness

Jorge A. Vila

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Abstract

An accurate estimation of the Protein Space size, in light of the factors that govern it, is a long-standing problem and of paramount importance in evolutionary biology, since it determines the nature of protein evolvability. A simple analysis will enable us to, firstly, reduce an unrealistic Protein Space size of ~10^130 sequences, for a 100-residues polypeptide chain, to ~10^9 functional proteins and, secondly, estimate a robust average-mutation rate per amino acid (x ~1.23) and infer from it, in light of the protein marginal stability, that only a fraction of the sequence will be available at any one time for a functional protein to evolve. Although this result does not solve the Protein Space vastness problem, frames it in a more rational one.

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Jorge A. Vila. 2020-08-26. About the Protein Space Vastness. https://arxiv.org/abs/2008.11602

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