Journal
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
Volume 60, Issue 2-3, Pages 261-268Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/S0168-1605(00)00316-0
Keywords
glycine betaine; salt stress; betL; sigma(B)
Categories
Ask authors/readers for more resources
Survival of the food-borne pathogen Listeria monocytogenes in environments of elevated osmolarity and reduced temperature is attributed, at least in part, to the accumulation of the trimethylammonium compound glycine betaine. Previously we identified betL, a gene encoding the secondary glycine betaine transporter BetL, which we linked to the salt tolerance of Listeria. In this report, we demonstrate that betL, preceded by a consensus sigma(B)-dependent promoter, is regulated by osmotic up-shock, at least in part at the level of transcription. Using allelic exchange mutagenesis we constructed an in-frame deletion in betL, and used this mutant to determine the role of BetL in contributing to the growth and survival of L. monocytogenes, both in a high risk food (Camembert cheese) and animal model. Our results indicate that while BetL plays an important role in glycine betaine mediated osmoprotection, mutating the gene does not significantly effect either the cryotolerance or virulence of the organism. (C) 2000 Elsevier Science B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available