Open AccessThe Listeria monocytogenes prfA P2 promoter is regulated by sigma B in a growth phase dependent manner
Author(s) -
Schwab Ute,
Bowen Barbara,
Nadon Celine,
Wiedmann Martin,
Boor Kathryn J.
Publication year - 2005
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/j.femsle.2005.03.025
Subject(s) - listeria monocytogenes , sigma factor , microbiology and biotechnology , listeria , phase (matter) , sigma , chemistry , bacteria , biology , promoter , genetics , gene , gene expression , physics , organic chemistry , quantum mechanics
Listeria monocytogenes prfA , encoding positive regulatory factor A, is transcribed from three promoters ( prfA P1, prfA P2, and P plcA ). The prfA P2 promoter was previously proposed to be sigma B (σ B )‐dependent. This hypothesis was tested by creating prfA promoter‐ gus transcriptional fusions in both L. monocytogenes wild‐type (wt) and Δ sigB backgrounds and then measuring (i) β‐glucuronidase (GUS) activities; (ii) gus mRNA transcript levels; and (iii) the presence or absence of GUS in cells by immunofluorescence staining. prfA P2‐directed expression increased as the wt L. monocytogenes strain entered stationary phase, whereas prfA P2‐directed expression was greatly reduced in the Δ sigB strain, confirming both growth phase‐ and σ B ‐dependent transcription of prfA P2. We conclude that prfA P2 is directly regulated by σ B .