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PubMed · 15490155

Using Lactococcus lactis for glutathione overproduction.

Yin Li·Jeroen Hugenholtz·Wilbert Sybesma·Tjakko Abee·Douwe Molenaar
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Abstract

Glutathione and gamma-glutamylcysteine were produced in Lactococcus lactis using a controlled expression system and the genes gshA and gshB from Escherichia coli encoding the enzymes gamma-glutamylcysteine synthetase and glutathione synthetase. High levels of gamma-glutamylcysteine were found in strains growing on chemically defined medium and expressing either gshA alone or both gshA and gshB. As anticipated, glutathione was found in a strain expressing gshA and gshB. The level of glutathione production could be increased by addition of the precursor amino acid cysteine to the medium. The addition of cysteine led to an increased activity of glutathione synthetase, which is remarkable because the amino acid is not a substrate of this enzyme. The final intracellular glutathione concentration attained was 358 nmol mg(-1) protein, which is the highest concentration reported for a bacterium, demonstrating the suitability of engineered L. lactis for fine-chemical production and as a model for studies of the impact of glutathione on flavour formation and other properties of food.

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Cloning, MolecularCulture MediaCysteineCytosolDipeptidesEscherichia coliGene Expression Regulation, BacterialGenes, BacterialGlutamate-Cysteine LigaseGlutathioneGlutathione SynthaseLactococcus lactisOxidative StressJournal ArticleResearch Support, Non-U.S. Gov't

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Yin Li, Jeroen Hugenholtz, Wilbert Sybesma, Tjakko Abee, Douwe Molenaar. 2004-10-13. Using Lactococcus lactis for glutathione overproduction.. https://doi.org/10.1007/s00253-004-1762-8

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