Advances in construction of acetic acid tolerance Escherichia coli

Abstract:

Acetic acid is a promising carbon source, as a common by-product in microbial fermentation. It widely exists in non-food fermentation feedstock media such as lignin-cellulose hydrolysates. However, high concentrations of acetic acid or acetate in media inhibit cell growth, biomass, yield and productivity. It is significant to transform acetic acid into value-added chemicals efficiently through engineered strains with improved acetic acid tolerance. This paper reviews the state-of-the-art progresses in the strategies of improving Escherichia coli acetic acid tolerance via metabolic engineering, adaptive laboratory evolution, global transcription machine engineering and CRISPR traceable genome engineering. Furthermore, we summarize the acetic acid tolerance response mechanisms in E. coli, including acetic acid assimilation metabolism, amino acid-dependent metabolism, ion transport system regulation, and cell membrane component modification in E. coli. Finally, we discuss the application of improved acetic acid tolerance strains and the future direction in this field.