Abstract:
:Biofilm formation by the periodontal pathogen Aggregatibacter actinomycetemcomitans is dependent upon autoinducer-2 (AI-2)-mediated quorum sensing. However, the components that link the detection of the AI-2 signal to downstream gene expression have not been determined. One potential regulator is the QseBC two-component system, which is part of the AI-2-dependent response pathway that controls biofilm formation in Escherichia coli. Here we show that the expression of QseBC in A. actinomycetemcomitans is induced by AI-2 and that induction requires the AI-2 receptors, LsrB and/or RbsB. Additionally, inactivation of qseC resulted in reduced biofilm growth. Since the ability to grow in biofilms is essential for A. actinomycetemcomitans virulence, strains that were deficient in QseC or the AI-2 receptors were examined in an in vivo mouse model of periodontitis. The DeltaqseC mutant induced significantly less alveolar bone resorption than the wild-type strain (P < 0.02). Bone loss in animals infected with the DeltaqseC strain was similar to that in sham-infected animals. The DeltalsrB, DeltarbsB, and DeltalsrB DeltarbsB strains also induced significantly less alveolar bone resorption than the wild type (P < 0.03, P < 0.02, and P < 0.01, respectively). However, bone loss induced by a DeltaluxS strain was indistinguishable from that induced by the wild type, suggesting that AI-2 produced by indigenous microflora in the murine oral cavity may complement the DeltaluxS mutation. Together, these results suggest that the QseBC two-component system is part of the AI-2 regulon and may link the detection of AI-2 to the regulation of downstream cellular processes that are involved in biofilm formation and virulence of A. actinomycetemcomitans.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Novak EA,Shao H,Daep CA,Demuth DRdoi
10.1128/IAI.01376-09subject
Has Abstractpub_date
2010-07-01 00:00:00pages
2919-26issue
7eissn
0019-9567issn
1098-5522pii
IAI.01376-09journal_volume
78pub_type
杂志文章abstract::Clostridium botulinum neurotoxins (BoNTs) are the most toxic proteins for humans. The current clostridial-derived vaccines against BoNT intoxication have limitations including production and accessibility. Conditions were established to express the soluble receptor binding domain (heavy-chain receptor [HCR]) of BoNT s...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.10.6998-7005.2005
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.7.2952-2959.1993
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.11.5107-5112.1998
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.5.3.337-338.1972
更新日期:1972-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.5.2690-2697.2005
更新日期:2005-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.39.2.565-568.1983
更新日期:1983-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
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更新日期:2005-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01695-07
更新日期:2008-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00795-13
更新日期:2013-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00019-08
更新日期:2008-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01343-09
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.40.3.917-923.1983
更新日期:1983-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.5.3.324-331.1972
更新日期:1972-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.5.1630-1635.1993
更新日期:1993-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.2.610-618.1993
更新日期:1993-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.2.399-410.1993
更新日期:1993-02-01 00:00:00
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journal_title:Infection and immunity
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更新日期:1985-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.20.1.130-135.1978
更新日期:1978-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
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更新日期:1999-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.3.1092-1099.1998
更新日期:1998-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.5.1770-1777.1996
更新日期:1996-05-01 00:00:00
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journal_title:Infection and immunity
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doi:10.1128/IAI.00344-19
更新日期:2019-09-19 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
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更新日期:2013-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.45.2.458-463.1984
更新日期:1984-08-01 00:00:00
abstract::The interferon-inducing capabilities of the three molecular segments of bacteriophage phi6 double-stranded ribonucleic acid increased with increasing molecular weight. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.10.1.284-285.1974
更新日期:1974-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.54.2.435-443.1986
更新日期:1986-11-01 00:00:00