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Updated: Jul 10, 2026
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Generic Protocol for Optimization of Heterologous Protein Production Using Automated Microbioreactor Technology
Published on: December 15, 2017
Lactococcus lactis, an efficient cell factory for recombinant protein production and secretion
E Morello1, L G Bermúdez-Humarán, D Llull
1Unité des Bactéries Lactiques et pathogènes Opportunistes (UBLO), INRA, Jouy-en-Josas, France.
Journal of Molecular Microbiology and Biotechnology
|October 25, 2007
Summary
Lactococcus lactis offers an efficient system for heterologous protein production. Enhancements like HtrA inactivation and SecDF complementation boost protein yields, making it a valuable cell factory.
Area of Science:
- Microbiology
- Biotechnology
- Molecular Biology
Background:
- Gram-positive bacteria are suitable for heterologous protein production due to secretion and purification ease.
- Lactococcus lactis is a promising alternative to Bacillus subtilis for protein expression.
Purpose of the Study:
- To review expression and secretion systems for heterologous protein production in L. lactis.
- To present novel tools for enhancing protein yield in L. lactis.
Main Methods:
- Inactivation of the HtrA protease.
- Complementation of the Sec machinery with Bacillus subtilis SecDF.
- Development of a novel expression/secretion system using P(Zn)zitR and SP(Exp4).
Main Results:
- HtrA inactivation and SecDF complementation increased heterologous protein yield.
- The P(Zn)zitR and SP(Exp4) system achieved staphylococcal nuclease production comparable to existing systems.
- Developed tools enhance L. lactis as a protein cell factory.
Conclusions:
- Lactococcus lactis is a viable and improvable platform for industrial protein production.
- Specific genetic modifications and expression systems significantly enhance protein yield.
- The developed toolbox expands L. lactis's utility in biotechnology.
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