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Doc-mediated cell killing in Shigella flexneri using a C1/LacI controlled expression system.

David A Schofield·Caroline Westwater·Joseph W Dolan·James S Norris·Michael G Schmidt
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Abstract

In this report we describe the development of a highly stringent and dually regulated promoter system for Shigella flexneri. Dual regulation was provided by utilizing a promoter susceptible to control by the bacteriophage P1 temperature-sensitive C1 repressor that in turn was under the transcriptional control of LacI. The level of induction/repression ratios observed was up to 3700-fold in S. flexneri. The general utility of this promoter system was evaluated by demonstrating that the bacteriophage P1 post-segregational killer protein Doc mediates a bactericidal effect in S. flexneri. This represents the first report of Doc (death on curing)-mediated killing in this Gram-negative species.

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Bacterial ProteinsBacteriophage P1Escherichia coli ProteinsGene Expression Regulation, BacterialGenetic VectorsLac RepressorsPromoter Regions, GeneticRepressor ProteinsShigella flexneriViral ProteinsEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov't

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David A Schofield, Caroline Westwater, Joseph W Dolan, James S Norris, Michael G Schmidt. 2002-10-08. Doc-mediated cell killing in Shigella flexneri using a C1/LacI controlled expression system.. https://doi.org/10.1111/j.1574-6968.2002.tb11396.x

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