Proteostasis is a master modulator of molecular evolution in bacteria

The bacterial protein quality control (PQC) network comprises a set of genes that promote proteostasis (proteome homeostasis) through proper protein folding and function via chaperones, proteases, and protein translational machinery. It thus participates in vital cellular processes and impacts organismal development and evolution. In this review, we examine how the PQC network influences the shape of genotype-phenotype maps and their influence on epistasis, evolvability, the navigability of protein space, and other important topics in contemporary evolutionary biology. We further examine a suite of secondary areas where proteostasis affects aspects of evolution, ecology, and physiology, including host-parasite interactions, and bioengineering. Summarizing, we highlight the centrality of PQC in modulating how functional protein forms arise from genotypic information. This examination aims to provide a richer mechanistic understanding of molecular evolution and highlights the possibility of manipulating information flow through the central dogma towards proteins with desirable phenotypes.