Crossing fitness valleys via double substitutions within codons.

ABSTRACT:

Background

Single nucleotide substitutions in protein-coding genes can be divided into synonymous (S), with little fitness effect, and non-synonymous (N) ones that alter amino acids and thus generally have a greater effect. Most of the N substitutions are affected by purifying selection that eliminates them from evolving populations. However, additional mutations of nearby bases potentially could alleviate the deleterious effect of single substitutions, making them subject to positive selection. To elucidate the effects of selection on double substitutions in all codons, it is critical to differentiate selection from mutational biases.

Results

We addressed the evolutionary regimes of within-codon double substitutions in 37 groups of closely related prokaryotic genomes from d

SUBMITTER: Belinky F 

PROVIDER: S-EPMC6916188 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature