Strategies for directed and adapted evolution as part of microbial strain engineering

The industrial production of chemicals by microorganisms usually requires improvements to the enzymes, pathways, and strain that go beyond the capacity of innate enzymes. To achieve these phenotypes and overcome our limited capacity to de novo design these parts, directed and adaptive evolutionary approaches are used to explore new functions. This review highlights the recent advances in both sequence diversity generation and selection strategies from traditional in vitro mutagenesis to novel in vivo continuous evolution applications. The focus here is on comparison of the different gene diversity methods in an attempt to distinguish the best strategy for protein or strain engineering for a given goal. Furthermore, the important role that screening and selection can play in advancing directed and adapted evolution is discussed. (c) 2018 Society of Chemical Industry