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A cell-cell signaling peptide activates the PlcR virulence regulon in bacteria of the Bacillus cereus group.

ABSTRACT: PlcR is a pleiotropic regulator that activates the expression of genes encoding various virulence factors, such as phospholipases C, proteases and hemolysins, in Bacillus thuringiensis and Bacillus cereus. Here we show that the activation mechanism is under the control of a small peptide: PapR. The papR gene belongs to the PlcR regulon and is located 70 bp downstream from plcR. It encodes a 48-amino-acid peptide. Disruption of the papR gene abolished expression of the PlcR regulon, resulting in a large decrease in hemolysis and virulence in insect larvae. We demonstrated that the PapR polypeptide was secreted, then reimported via the oligopeptide permease Opp. Once inside the cell, a processed form of PapR, presumably a pentapeptide, activated the PlcR regulon by allowing PlcR to bind to its DNA target. This activating mechanism was found to be strain specific, with this specificity determined by the first residue of the penta peptide.

SUBMITTER: Slamti L

PROVIDER: S-EPMC126190 | biostudies-literature | 2002 Sep

REPOSITORIES: biostudies-literature

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A cell-cell signaling peptide activates the PlcR virulence regulon in bacteria of the Bacillus cereus group.

Slamti Leyla L Lereclus Didier D

The EMBO journal 20020901 17

PlcR is a pleiotropic regulator that activates the expression of genes encoding various virulence factors, such as phospholipases C, proteases and hemolysins, in Bacillus thuringiensis and Bacillus cereus. Here we show that the activation mechanism is under the control of a small peptide: PapR. The papR gene belongs to the PlcR regulon and is located 70 bp downstream from plcR. It encodes a 48-amino-acid peptide. Disruption of the papR gene abolished expression of the PlcR regulon, resulting in ...[more]

PMID: 12198157

Similar Datasets

The PlcR virulence regulon of Bacillus cereus.

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| S-EPMC2464732 | biostudies-literature

A spontaneous translational fusion of Bacillus cereus PlcR and PapR activates transcription of PlcR-dependent genes in Bacillus anthracis via binding with a specific palindromic sequence.

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Unusual group II introns in bacteria of the Bacillus cereus group.

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PapR peptide maturation: role of the NprB protease in Bacillus cereus 569 PlcR/PapR global gene regulation.

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Divergence of the SigB regulon and pathogenesis of the Bacillus cereus sensu lato group.

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Project description:In this study we developed a multilocus sequence typing (MLST) scheme for bacteria of the Bacillus cereus group. This group, which includes the species B. cereus, B. thuringiensis, B. weihenstephanensis, and B. anthracis, is known to be genetically very diverse. It is also very important because it comprises pathogenic organisms as well as bacteria with industrial applications. The MLST system was established by using 77 strains having various origins, including humans, animals, food, and soil. A total of 67 of these strains had been analyzed previously by multilocus enzyme electrophoresis, and they were selected to represent the genetic diversity of this group of bacteria. Primers were designed for conserved regions of housekeeping genes, and 330- to 504-bp internal fragments of seven such genes, adk, ccpA, ftsA, glpT, pyrE, recF, and sucC, were sequenced for all strains. The number of alleles at individual loci ranged from 25 to 40, and a total of 53 allelic profiles or sequence types (STs) were distinguished. Analysis of the sequence data showed that the population structure of the B. cereus group is weakly clonal. In particular, all five B. anthracis isolates analyzed had the same ST. The MLST scheme which we developed has a high level of resolution and should be an excellent tool for studying the population structure and epidemiology of the B. cereus group.

| S-EPMC321270 | biostudies-literature

Population structure of the Bacillus cereus group as determined by sequence analysis of six housekeeping genes and the plcR Gene.

Project description:The population structure of the Bacillus cereus group (52 strains of B. anthracis, B. cereus, and B. thuringiensis) was investigated by sequencing seven gene fragments (rpoB, gyrB, pycA, mdh, mbl, mutS, and plcR). Most of the strains were classifiable into two large subgroups in six housekeeping gene trees but not in the plcR tree. In addition, several consistent clusters were identified, which were unrelated to species distinction. Moreover, interrelationships among these clusters were incongruent in each gene tree. The incongruence length difference test and split decomposition analyses also showed incongruences between genes, suggesting horizontal gene transfer. The plcR gene was observed to have characteristics that differed from those of the other genes in terms of phylogenetic topology and pattern of sequence diversity. Thus, we suggest that the evolutionary history of the PlcR regulon differs from those of the other chromosomal genes and that recombination of the plcR gene may be frequent. The homogeneity of B. anthracis, which is depicted as an independent lineage in phylogenetic trees, is suggested to be of recent origin or to be due to the narrow taxonomic definition of species.

| S-EPMC517475 | biostudies-literature

The YvfTU two-component system is involved in plcR expression in Bacillus cereus.

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| S-EPMC2588459 | biostudies-literature

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