From laboratory to pilot plant E. coli fed-batch cultures: optimizing the cellular environment for protein...

Area of Science:

• Biotechnology
• Molecular Biology
• Biochemical Engineering

Background:

• Post-induction conditions critically impact recombinant protein production quantity and quality in E. coli fed-batch cultures.
• Understanding cellular environment factors is key to optimizing recombinant aldolase (RhuA) production.

Purpose of the Study:

• To analyze operational modes for E. coli fed-batch cultures to improve recombinant RhuA production.
• To investigate the effects of constant vs. exponential addition profiles and amino acid supplementation on RhuA production.

Main Methods:

• Fed-batch cultivation of E. coli for recombinant RhuA production.
• Analysis of constant and exponential substrate addition profiles.
• Supplementation with leucine to assess impact on protein quality and metabolic overload.

Main Results:

• A constant addition profile yielded higher specific aldolase production compared to an exponential profile.
• Leucine supplementation improved RhuA protein quality (activity units per mg RhuA), mitigating metabolic overload.
• Scaled-up pilot plant production achieved double the laboratory yield (45,000 U L⁻¹) with high protein quality (11.3 U mg⁻¹ RhuA).

Conclusions:

• Constant addition profiles offer a more stable cellular environment for enhanced recombinant protein production.
• Amino acid supplementation, specifically leucine, is a viable strategy to improve protein quality and alleviate metabolic stress.
• The optimized process demonstrates significant improvements in both yield and quality for RhuA production at a pilot scale.