Identification of the Gene Encoding the Alternative Sigma Factor ς B from Listeria monocytogenes and Its Role in Osmotolerance

• DOI: 10.1128/jb.180.17.4547-4554.1998
• Publication Date: 2019-12-31T16:26:25Z
• Authors: Lynne A. Becker; Mehmet Sevket Çetin; Robert W. Hutkins; Andrew K. Benson
• Keywords: Sigma factor; Regulon; Betaine; rpoS; Osmotic concentration

ABSTRACT Listeria monocytogenes is well known for its robust physiology, which permits growth at low temperatures under conditions of high osmolarity and pH. Although studies have provided insight into the mechanisms used by L. to allay physiological consequences these adverse environments, little about how responses are coordinated. In presented here, we cloned sigB gene several rsb genes from , encoding homologs alternative sigma factor ς B RsbUVWX proteins, govern transcription a general stress regulon in related bacterium Bacillus subtilis . The B. similar sequence physical organization; however, observed that activity was uniquely responsive osmotic upshifting, temperature downshifting, presence EDTA medium. magnitude response greatest after an upshift, suggesting role coordinating A null mutation led substantial defects ability use betaine carnitine as osmoprotectants. Subsequent measurements transport confirmed absence reduced cells accumulate betaine. Thus, coordinates variety chemical signals, function facilitates strength.