FeedER: a feedback-regulated enzyme-based slow-release system for fed-batch cultivation in microtiter plates

Area of Science:

• Biotechnology
• Bioprocess Engineering
• Microbial Cultivation

Background:

• Microcultivation systems are crucial for strain phenotyping and bioprocess engineering.
• Existing systems primarily support batch processes, limiting their application for industrial fed-batch cultivations.
• Fed-batch processes are more prevalent in industrial bioprocessing due to their efficiency.

Purpose of the Study:

• To develop a novel microscale system for realizing exponential fed-batch cultivations.
• To enable automated, parallel fed-batch experiments for accelerated bioprocess development.
• To overcome limitations of current microcultivation systems in performing fed-batch processes.

Main Methods:

• Development of a feedback-regulated enzyme-based slow-release system (FeedER).
• Integration of a customized process control system with Mini Pilot Plant technology.
• Automated dosage of Amyloglucosidase for dextrin cleavage and glucose release, with pH control via ammonium hydroxide addition.

Main Results:

• Successful demonstration of fed-batch growth for Corynebacterium glutamicum, Pichia pastoris, and Escherichia coli.
• Achieved two times higher product yields in a C. glutamicum GFP producer strain under fed-batch versus batch conditions.
• Enabled 48 parallel, automated, and miniaturized fed-batch experiments.

Conclusions:

• FeedER system effectively enables exponential fed-batch microcultivations.
• The system accelerates industrial bioprocess development at the screening stage.
• Automated fed-batch cultivation in microscale significantly enhances product yield for microbial strains.