Rhamnose-Inducible Gene Expression in Listeria monocytogenes

• Published in: PloS one Vol. 7; no. 8; p. e43444
• Main Authors: Fieseler, Lars, Schmitter, Sibylle, Teiserskas, Justinas, Loessner, Martin J.
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 22.08.2012; Public Library of Science (PLoS)
• Subjects: Acid production; Antigens; Biology; Cancer; Carbohydrates; Catabolite repression; Cell Line; Cloning; Cytosol; Deoxyribonucleic acid; DNA; Drug resistance; E coli; Food contamination & poisoning; Food processing industry; Gene expression; Gene Expression Regulation, Bacterial - drug effects; Genes, Bacterial - genetics; Genes, Reporter - genetics; Genetic aspects; Genetic Vectors - genetics; Glucose; Humans; Intracellular; Intracellular Space - drug effects; Intracellular Space - genetics; Listeria; Listeria monocytogenes; Listeria monocytogenes - cytology; Listeria monocytogenes - drug effects; Listeria monocytogenes - genetics; Listeria monocytogenes - physiology; Macrophages; Macrophages - physiology; Metabolism; Nutrition; Phenotypes; Physiological aspects; Promoter Regions, Genetic - drug effects; Promoter Regions, Genetic - genetics; Proteins; Rhamnose; Rhamnose - pharmacology; Transcription initiation; Transcription, Genetic - drug effects; Vaccines; Switzerland
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0043444

Acid production from rhamnose is a characteristic phenotype of Listeria monocytogenes. We report the identification of the rhamnose transport and utilization operon located at lmo2846 to lmo2851, including the rhamnose-dependent promoter P(rha). Expression of reporter genes under control of P(rha) on a single copy integration vector demonstrated its suitability for inducible gene expression in L. monocytogenes. Transcription initiation from P(rha) is dose dependent, and a concentration as low as 100 µM rhamnose was found sufficient for induction. Moreover, P(rha) is subject to glucose catabolite repression, which provides additional options for strict control of expression. Infection of human THP1 macrophages revealed that P(rha) is repressed in intracellular L. monocytogenes, which is explained by the absence of rhamnose in the cytosol and possible interference by catabolite repression. The P(rha) promoter provides a novel and useful tool for triggering gene expression in extracellular L. monocytogenes, whereas intracellular conditions prevent transcription from this promoter.