Abstract:
:In gram-negative bacteria, the RNA-binding protein Hfq has emerged as an important regulatory factor in a variety of physiological processes, including stress resistance and virulence. In Escherichia coli, Hfq modulates the stability or the translation of mRNAs and interacts with numerous small regulatory RNAs. Here, we studied the role of Hfq in the stress tolerance and virulence of the gram-positive food-borne human pathogen Listeria monocytogenes. We present evidence that Hfq is involved in the ability of L. monocytogenes to tolerate osmotic and ethanol stress and contributes to long-term survival under amino acid-limiting conditions. However, Hfq is not required for resistance to acid and oxidative stress. Transcription of hfq is induced under various stress conditions, including osmotic and ethanol stress and at the entry into the stationary growth phase, thus supporting the view that Hfq is important for the growth and survival of L. monocytogenes in harsh environments. The stress-inducible transcription of hfq depends on the alternative sigma factor sigmaB, which controls the expression of numerous stress- and virulence-associated genes in L. monocytogenes. Infection studies showed that Hfq contributes to pathogenesis in mice, yet plays no role in the infection of cultured cell lines. This study provides, for the first time, information on the role of Hfq in the stress tolerance and virulence of a gram-positive pathogen.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Christiansen JK,Larsen MH,Ingmer H,Søgaard-Andersen L,Kallipolitis BHdoi
10.1128/JB.186.11.3355-3362.2004keywords:
subject
Has Abstractpub_date
2004-06-01 00:00:00pages
3355-62issue
11eissn
0021-9193issn
1098-5530pii
186/11/3355journal_volume
186pub_type
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journal_title:Journal of bacteriology
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doi:10.1128/JB.105.1.445-448.1971
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journal_title:Journal of bacteriology
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journal_title:Journal of bacteriology
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更新日期:1970-01-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:2002-08-01 00:00:00
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pub_type: 杂志文章
doi:10.1128/jb.175.8.2292-2303.1993
更新日期:1993-04-01 00:00:00
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