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.

Species-specific differences in the activity of PrfA, the key regulator of listerial virulence genes.

PrfA, the master regulator of LIPI-1, is indispensable for the pathogenesis of the human pathogen Listeria monocytogenes and the animal pathogen Listeria ivanovii. PrfA is also present in the apathogenic species Listeria seeligeri, and in this study, we elucidate the differences between PrfA proteins from the pathogenic and apathogenic species of the genus Listeria. PrfA proteins of L.