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Six putative two-component regulatory systems isolated from Lactococcus lactis subsp. cremoris MG1363.

Mary O'Connell-Motherway·Douwe van Sinderen·Françoise Morel-Deville·Gerald F Fitzgerald·S Dusko Ehrlich·Patrice Morel
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Abstract

The genetic elements specifying six putative two-component regulatory systems (2CSs) were identified on the chromosome of Lactococcus lactis MG1363. These 2CSs appear to represent distinct loci, each containing a histidine kinase and response-regulator-encoding gene pair. Transcriptional analysis of the six 2CSs was performed either by generating transcriptional fusions to a reporter gene or by primer extension. Two of the systems appeared to be expressed constitutively at a high level, whilst the remaining four exhibited growth-phase-dependent expression. Insertional mutagenesis established that the two constitutively expressed 2CSs are necessary for normal cell growth and/or survival. Mutational analysis of the remaining four systems revealed that they are implicated in susceptibility to extreme pH, osmotic or oxidative conditions, or the regulation of phosphatase activity in L. lactis.

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Amino Acid SequenceBase SequenceGene Expression Regulation, BacterialLactococcus lactisMolecular Sequence DataSequence AlignmentSignal TransductionJournal ArticleResearch Support, Non-U.S. Gov't

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Mary O'Connell-Motherway, Douwe van Sinderen, Françoise Morel-Deville, Gerald F Fitzgerald, S Dusko Ehrlich, Patrice Morel. 2000. Six putative two-component regulatory systems isolated from Lactococcus lactis subsp. cremoris MG1363.. https://doi.org/10.1099/00221287-146-4-935

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