Interference of components of the phosphoenolpyruvate phosphotransferase system with the central virulence gene regulator PrfA of Listeria monocytogenes.
Analysis of Listeria monocytogenes ptsH, hprK, and ccpA mutants defective in carbon catabolite repression (CCR) control revealed significant alterations in the expression of PrfA-dependent genes. The hprK mutant showed high up-regulation of PrfA-dependent virulence genes upon growth in glucose-containing medium whereas expression of these genes was even slightly down-regulated in the ccpA mutant compared to the wild-type strain. The ptsH mutant could only grow in a rich culture medium, and here the PrfA-dependent genes were up-regulated as in the hprK mutant. As expected, HPr-Ser-P was not produced in the hprK and ptsH mutants and synthesized at a similar level in the ccpA mutant as in the wild-type strain. However, no direct correlation was found between the level of HPr-Ser-P or HPr-His-P and PrfA activity when L. monocytogenes was grown in minimal medium with different phosphotransferase system (PTS) carbohydrates. Comparison of the transcript profiles of the hprK and ccpA mutants with that of the wild-type strain indicates that the up-regulation of the PrfA-dependent virulence genes in the hprK mutant correlates with the down-regulation of genes known to be controlled by the efficiency of PTS-mediated glucose transport. Furthermore, growth in the presence of the non-PTS substrate glycerol results in high PrfA activity. These data suggest that it is not the component(s) of the CCR or the common PTS pathway but, rather, the component(s) of subsequent steps that seem to be involved in the modulation of PrfA activity.
Mertins
Sonja
S
Lehrstuhl für Mikrobiologie, Biozentrum, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany.
Joseph
Biju
B
Goetz
Monika
M
Ecke
Regina
R
Seidel
Gerald
G
Sprehe
Mareen
M
Hillen
Wolfgang
W
Goebel
Werner
W
Müller-Altrock
Stefanie
S
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D015153:Blotting, Western; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D005947:Glucose / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D008089:Listeria monocytogenes / Q000235:genetics* / Q000378:metabolism; D008957:Models, Genetic; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D010454:Peptide Termination Factors / Q000235:genetics* / Q000378:metabolism; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000235:genetics* / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D014774:Virulence / Q000235:genetics
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D010454:Peptide Termination Factors; D012097:Repressor Proteins; C069286:catabolite control proteins, bacteria; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; D005947:Glucose; D005990:Glycerol