Abstract:
:Most strains of Shigella flexneri 2a and enteroaggregative Escherichia coli carry a highly conserved chromosomal locus which encodes a 109-kDa secreted mucinase (called Pic) and, on the opposite strand in overlapping fashion, an oligomeric enterotoxin called ShET1, encoded by the setA and setB genes. Here, we characterize the genetic regulation of these overlapping genes. Our data suggest that pic and the setBA loci are transcribed as complementary 4-kb mRNA species. The major pic promoter is maximally activated at 37 degrees C in exponential growth phase. Our data suggest that the setB gene is transcribed from a promoter which lies more than 1.5 kb upstream of the setB structural gene; setA may be transcribed via readthrough of the setB transcript and possibly by its own promoter. The long leader of the setB gene provides a strong silencing effect on setB transcription. The signals which provide relief from setB silencing are not clear, but significant induction is observed in a continuous anaerobic culture of human fecal bacteria, suggesting that some complex characteristics of the human intestine act to lift repression of setB expression. Our studies provide the first insights into the mechanisms affecting expression of this unusual virulence locus.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Behrens M,Sheikh J,Nataro JPdoi
10.1128/iai.70.6.2915-2925.2002keywords:
subject
Has Abstractpub_date
2002-06-01 00:00:00pages
2915-25issue
6eissn
0019-9567issn
1098-5522journal_volume
70pub_type
杂志文章abstract::When rabbit peritoneal exudate cells were incubated for 24 and 48 h with phytohemagglutinin-activated lymphocytes or their culture supernatants, two times as many cells remained adherent to culture slides as in the controls. More spreading cells were found among the adherent cells in the stimulated cultures. Eighty pe...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.13.5.1442-1448.1976
更新日期:1976-05-01 00:00:00
abstract::The appearance of lymphotoxin in the culture fluid of phytohemagglutinin (PHA)-stimulated mouse spleen cells required two cell fractions that were separated by adherence to plastic. Upon stimulation with PHA, neither cell fraction alone produced significant amounts of lymphotoxin; however, when the cell fractions were...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.36.3.1028-1035.1982
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journal_title:Infection and immunity
pub_type: 杂志文章
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journal_title:Infection and immunity
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更新日期:2000-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.7.3093-3097.1993
更新日期:1993-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.10.4075-4081.1997
更新日期:1997-10-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.1.289-294.1993
更新日期:1993-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.5.1051-1057.1987
更新日期:1987-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.37.3.1112-1118.1982
更新日期:1982-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.8.3793-3799.1999
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.67.11.5634-5641.1999
更新日期:1999-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.52.2.421-427.1986
更新日期:1986-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01439-15
更新日期:2016-07-21 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.5.2618-2627.2004
更新日期:2004-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.21.1.333-336.1978
更新日期:1978-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.15.2.444-452.1977
更新日期:1977-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.31.2.554-559.1981
更新日期:1981-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.10.4067-4073.1996
更新日期:1996-10-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.7.4354-4362.2005
更新日期:2005-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.12.5267-5282.1992
更新日期:1992-12-01 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:1992-10-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.1.65-69.1998
更新日期:1998-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.50.1.304-309.1985
更新日期:1985-10-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.8.3054-3061.1995
更新日期:1995-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.7.3857-3865.2003
更新日期:2003-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00487-15
更新日期:2015-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.53.3.553-559.1986
更新日期:1986-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.4.909-915.1987
更新日期:1987-04-01 00:00:00
abstract::Altogether 171 serum specimens from 58 patients with heterophil antibody-positive infectious monomucleosis were studied for antibody response to Epstein-Barr virus (EBV). The sera were tested for fluorescent immunoglobulin G (IgG) and IgM gel-precipitating (GP) and complement-fixing (CF) antibodies to EBV. All 58 pati...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.11.1.42-51.1975
更新日期:1975-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.12.3793-3797.1989
更新日期:1989-12-01 00:00:00