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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, RESULTS. Meshes: Amino Acid Sequence, Animals, Bacillaceae Infections, Bacillus cereus, Bacterial Proteins, Gene Expression Profiling, Gene Expression Regulation, Bacterial, Genes, Bacterial, Genes, Reporter, Lepidoptera, Molecular Sequence Data, Mutation, Plasmids, Proteomics, RNA, Bacterial, Regulon, Reverse Transcriptase Polymerase Chain Reaction, Sequence Alignment, Sequence Analysis, DNA, Trans-Activators, Transcription, Genetic, Virulence, Virulence Factors.
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Is the YvfTU two-component system involved in plcR expression in Bacillus cereus? Context: Most extracellular virulence factors produced by Bacillus cereus are regulated by the pleiotropic transcriptional activator PlcR. Among strains belonging to the B. cereus group, the plcR gene is always located in the vicinity of genes encoding the YvfTU two-component system. The putative role of YvfTU in the expression of the PlcR regulon was therefore investigated. Expression of the plcR gene was monitored using a transcriptional fusion with a lacZ reporter gene in a yvfTU mutant and in its B. cereus ATCC 14579 parental strain. Two hours after the onset of the stationary phase, a stage at which the PlcR regulon is highly expressed, the plcR expression in the yvfTU mutant was only 50% of that of its parental strain. In addition to the reduced plcR expression in the yvfTU mutant, a few members of the PlcR regulon showed a differential expression, as revealed by transcriptomic and proteomic analyses. The virulence of the yvfTU mutant in a Galleria mellonella insect model was slightly lower than that of the parental strain.
assistant
The YvfTU two-component system is not required for the expression of most of the virulence factors belonging to the PlcR regulon. However, YvfTU is involved in expression of plcR, a major regulator of virulence in B. cereus. Final Decision: yes