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A xylose-inducible expression system for Lactococcus lactis.

Anderson Miyoshi·Emmanuel Jamet·Jacqueline Commissaire·Pierre Renault·Philippe Langella·Vasco Azevedo
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Abstract

A new controlled production system to target heterologous proteins to cytoplasm or extracellular medium is described for Lactococcus lactis NCDO2118. It is based on the use of a xylose-inducible lactococcal promoter, P(xylT). The capacities of this system to produce cytoplasmic and secreted proteins were tested using the Staphylococcus aureus nuclease gene (nuc) fused or not to the lactococcal Usp45 signal peptide. Xylose-inducible nuc expression is tightly controlled and resulted in high-level and long-term protein production, and correct targeting either to the cytoplasm or to the extracellular medium. Furthermore, this expression system is versatile and can be switched on or off easily by adding either xylose or glucose, respectively. These results confirm the potential of this expression system as an alternative and useful tool for the production of proteins of interest in L. lactis.

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Gene Expression Regulation, BacterialGenetic VectorsLactococcus lactisMicrococcal NucleasePromoter Regions, GeneticRecombinant Fusion ProteinsXyloseJournal ArticleResearch Support, Non-U.S. Gov't

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Anderson Miyoshi, Emmanuel Jamet, Jacqueline Commissaire, Pierre Renault, Philippe Langella, Vasco Azevedo. 2004-10-15. A xylose-inducible expression system for Lactococcus lactis.. https://doi.org/10.1016/j.femsle.2004.08.018

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