Pleiotropic control of Listeria monocytogenes virulence factors by a gene that is autoregulated.
Evidence for pleiotropic activation of virulence genes in Listeria monocytogenes is presented. A complementation study of a spontaneous prfA-deletion mutant and analysis of cassette and transposon insertion mutants showed that the gene prfA activates the transcription of four independent genes which code for a phosphatidyl-inositol-specific phospholipase C (gene plcA), listeriolysin O (gene hlyA), a metallo-protease (gene prtA) and a lecithinase (gene prtC). Transcription of prfA is not constitutive. During the growth phase, two peaks of prfA transcript accumulation were observed: the first was during exponential growth, and the second was at the beginning of the stationary phase. In addition, two prfA-specific transcripts of 2.2 kb and 1 kb are detected. Early in exponential growth, prfA is co-transcribed with plcA which lies upstream prfA, giving rise to the 2.2 kb plcA-prfA transcript. In late-exponential growth and at the beginning of the stationary phase, prfA transcripts of 1 kb are predominantly detected. Our results demonstrate that since prfA controls plcA transcription, it also regulates its own synthesis.
Mengaud
J
J
Unité de Génie Microbiologique, Institut Pasteur, Paris, France.
Dramsi
S
S
Gouin
E
E
Vazquez-Boland
J A
JA
Milon
G
G
Cossart
P
P
D000595:Amino Acid Sequence; D001427:Bacterial Toxins; D001483:Base Sequence; D002872:Chromosome Deletion; D004252:DNA Mutational Analysis; D004251:DNA Transposable Elements; D015964:Gene Expression Regulation, Bacterial; D005816:Genetic Complementation Test; D006360:Heat-Shock Proteins / Q000235:genetics; D006460:Hemolysin Proteins; D008089:Listeria monocytogenes / Q000235:genetics* / Q000472:pathogenicity; D008666:Metalloendopeptidases / Q000235:genetics; D008969:Molecular Sequence Data; D010740:Phospholipases / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D014158:Transcription, Genetic; D010738:Type C Phospholipases / Q000235:genetics; D014774:Virulence / Q000235:genetics*
D001427:Bacterial Toxins; D004251:DNA Transposable Elements; D006360:Heat-Shock Proteins; D006460:Hemolysin Proteins; D010740:Phospholipases; D010738:Type C Phospholipases; D008666:Metalloendopeptidases; C038705:hlyA protein, Listeria monocytogenes