Metabolic engineering of E. coli for β-alanine production using a multi-biosensor enabled approach

Area of Science:

• Biotechnology
• Metabolic Engineering
• Synthetic Biology

Background:

• Beta-alanine (β-alanine) is a crucial biomolecule with applications in nutraceuticals, pharmaceuticals, and chemical synthesis.
• Eco-friendly bioproduction of β-alanine is gaining traction as a sustainable alternative to petroleum-based chemical synthesis.

Purpose of the Study:

• To develop high-throughput screening platforms for enhancing de novo β-alanine biosynthesis.
• To engineer E. coli for improved β-alanine production from glucose.

Main Methods:

• Development of two in vivo high-throughput screening platforms.
• Identification of ribonuclease E (rne) and a redox-cofactor balancing module for enhanced biosynthesis.
• Rational engineering of upstream and downstream metabolic modules.
• Optimization of fermentation conditions using screening platforms.

Main Results:

• Engineered E. coli showed a 3.4-fold increase in β-alanine yield (0.85 mol/mol glucose) and a 6.6-fold increase in specific production (0.74 g/L/OD600).
• The highest yielding strain achieved 1.08 mol β-alanine/mol glucose, representing 81.2% of the theoretical yield.
• The final strain produced 6.98 g/L β-alanine in batch bioreactors and 34.8 g/L via whole-cell catalysis.

Conclusions:

• Biosensor-enabled high-throughput screening is effective for optimizing β-alanine production.
• Metabolic engineering strategies significantly improved β-alanine yield and productivity.
• The developed platform offers a sustainable and efficient bioproduction route for β-alanine.