An autoinducible trp‐T7 expression system for production of proteins and biochemicals in Escherichia coli. Issue 5 (18th February 2020)

• Record Type: Journal Article
• Authors: Landberg, Jenny; Mundhada, Hemanshu; Nielsen, Alex Toftgaard
• Is Part Of: Biotechnology and bioengineering. Volume 117:Issue 5(2020)
• Page Start: 1513
• Page End: 1524
• Publication Date: 2020-02-18
• Subjects: Escherichia coli -- inducible promoter -- l‐serine -- tryptophan; Biotechnology -- Periodicals; Bioengineering -- Periodicals; 660.6
• DOI: 10.1002/bit.27297
• Languages: English
• ISSNs: 0006-3592

Abstract

Abstract: Inducible expression systems can be applied to control the expression of proteins or biochemical pathways in cell factories. However, several of the established systems require the addition of expensive inducers, making them unfeasible for large‐scale production. Here, we establish a genome integrated trp‐T7 expression system where tryptophan can be used to control the induction of a gene or a metabolic pathway. We show that the initiation of gene expression from low‐ and high‐copy vectors can be tuned by varying the initial concentration of tryptophan or yeast extract, and that expression is tightly regulated and homogenous when compared with the commonly used lac‐T7 system. Finally, we apply the trp‐T7 expression system for the production of l ‐serine, where we reach titers of 26 g/L in fed‐batch fermentation. Abstract : Inducible expression of biochemicals and proteins is widely used. Here, a tryptophan‐controlled, tightly regulated and tuneable T7‐based induction system is described and shown to be compatible with fed‐batch fermentation.