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Generic Protocol for Optimization of Heterologous Protein Production Using Automated Microbioreactor Technology
Published on: December 15, 2017
Ornithine cyclodeaminase-based proline production by Corynebacterium glutamicum
Jaide Vold Korgaard Jensen1, Volker Fritz Wendisch
1Genetics of Prokaryotes, Faculty of Biology & CeBiTec, University of Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany.
Microbial Cell Factories
|June 29, 2013
Summary
This study engineered Corynebacterium glutamicum to produce L-proline, an amino acid. By introducing a specific enzyme, researchers successfully expanded the bacterium
Area of Science:
- Microbiology
- Metabolic Engineering
- Biotechnology
Background:
- Corynebacterium glutamicum is a versatile soil bacterium known for glutamate production.
- Proline biosynthesis can occur via glutamate or ornithine pathways.
- An ornithine-overproducing strain (ORN1) was previously developed.
Purpose of the Study:
- To engineer the ORN1 strain for L-proline production.
- To investigate the efficacy of heterologous ornithine cyclodeaminase (ocd) expression.
- To enhance proline yields through metabolic engineering.
Main Methods:
- Heterologous expression of ocd from Pseudomonas putida in C. glutamicum ORN1.
- Overexpression of a feedback-alleviated N-acetylglutamate kinase.
- Fermentation and analysis of proline production and by-products.
Main Results:
- Plasmid-based expression of C. glutamicum ocd did not yield proline.
- Expression of P. putida ocd resulted in proline production (0.31 g/g glucose).
- Enhanced proline yield (0.36 g/g glucose) and reduced by-products via feedback-alleviation.
Conclusions:
- The product spectrum of C. glutamicum ORN1 was successfully expanded to include L-proline.
- This engineering approach demonstrates potential for industrial amino acid production.
- Further development could enable production of glutamate family amino acids and diamines.
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