Enhancing ectoine production by recombinant Escherichia coli through step-wise fermentation optimization strategy...

Area of Science:

• Biotechnology
• Microbial Fermentation
• Metabolic Engineering

Background:

• Ectoine is a valuable osmoprotectant with diverse applications.
• Current ectoine production methods require optimization for industrial scalability.
• Recombinant Escherichia coli offers a promising platform for ectoine biosynthesis.

Purpose of the Study:

• To construct a recombinant Escherichia coli strain for ectoine production.
• To systematically investigate and optimize fermentation parameters for enhanced ectoine yields.
• To develop a scalable fermentation strategy for commercial ectoine manufacturing.

Main Methods:

• Construction of recombinant Escherichia coli ET01 by introducing the ectABC operon.
• Optimization of fermentation using pH-feedback and glucose-controlled feeding strategies.
• Investigation of dissolved oxygen (DO) levels and development of a DO control strategy.

Main Results:

• Initial optimization achieved an ectoine titer of 25.5 g/L, an 8.8-fold increase.
• A two-stage fermentation strategy, incorporating DO control, resulted in a record 47.8 g/L ectoine.
• The developed fermentation regulation strategy significantly improved ectoine production in E. coli.

Conclusions:

• The engineered E. coli strain and optimized fermentation strategy are highly effective for ectoine production.
• The study presents the highest ectoine yield achieved via E. coli fermentation to date.
• The developed fermentation regulation strategy holds potential for the commercial-scale production of ectoine.