How the bacterial pathogen Listeria monocytogenes mediates the switch from environmental Dr. Jekyll to pathogenic Mr. Hyde - PubMed (original) (raw)

FIG. 1.

(A) Map of the L. monocytogenes plcA-prfA region, not drawn to scale. The heavy line at the bottom of the panel represents the DNA sequence, with gene coding regions indicated as boxes; the four lines above the gene coding region represent possible mRNA transcripts, including a 1.1-kb plcA transcript, a 2.1-kb plcA_-prfA bicistronic transcript, and 0.9- and 0.8-kb prfA transcripts (11, 13, 42, 67, 73, 91). Transcriptional start sites are indicated by bent arrows, and the plcA transcription terminator is indicated by a stem-loop. (B) DNA sequence of the prfA promoter region (46, 91). Triangles indicate transcriptional start sites identified for P1_prfA and P2_prfA_. The σA-dependent P1_prfA_ promoter is in boldface and underlined once. Two adjacent transcriptional start sites, possibly reflecting transcription from either the σA-dependent or σB-dependent promoter comprising the P2_prfA_ region, are marked by triangles (46). In the P2_prfA_ region, the σB-dependent promoter is in boldface and underlined twice; the proposed σA-dependent promoter is marked by double lines above the sequence, and the PrfA binding box (100), which is immediately upstream of the P2 promoter region, is marked by a dotted line beneath the sequence.