Abstract:
:The study of how bacteria respond to and obtain divalent metal ions provides insight into the regulation of virulence factors in the host environment. Regulation of metal permease operons in gram-positive bacteria may involve the binding of metal-responsive repressors to palindromic domains in their control regions. The Streptococcus parasanguis fimA operon, which encodes an ATP-binding cassette (ABC) transporter system with sequence homology to the LraI family of metal transporters, possesses a palindromic regulatory region with high homology to that of the Streptococcus gordonii ScaR binding domain. Mapping of the promoter and regulatory regions of fimA and the divergently transcribed pepO gene, which encodes a zinc metalloendopeptidase, indicated that their promoter and regulatory elements overlap. fimA had one transcriptional start site, whereas pepO had three. Analysis of truncated versions of the pepO promoter suggested that all three transcriptional start sites are functional. Analysis of promoter activity under various environmental conditions indicated that the fimA operon promoter and the pepO promoter are not coordinately regulated. The fimA operon is responsive to changes in Mn(2+) concentration, but the pepO promoter is not. A S. parasanguis fimA mutant showed a growth deficiency under conditions of limiting Mn(2+). This deficiency was not alleviated by compensation with either Mg(2+) or Fe(3+). Wild-type S. parasanguis could take up Mn(2+) and Fe(3+), while the fimA mutant showed a marked reduction in this ability. These data suggested that FimA is a component of a metal transporter system capable of transporting both Mn(2+) and Fe(3+). FimA expression itself was shown to be responsive to Mn(2+) concentration, but not to availability of Fe(3+) or Mg(2+).
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Oetjen J,Fives-Taylor P,Froeliger EHdoi
10.1128/iai.70.10.5706-5714.2002keywords:
subject
Has Abstractpub_date
2002-10-01 00:00:00pages
5706-14issue
10eissn
0019-9567issn
1098-5522journal_volume
70pub_type
杂志文章abstract::Shiga toxin-producing Escherichia coli (STEC) strains are responsible for causing hemolytic-uremic syndrome (HUS), and systemic administration of Shiga toxin (Stx)-specific human monoclonal antibodies (HuMAbs) is considered a promising approach for prevention or treatment of the disease in children. The goal of the pr...
journal_title:Infection and immunity
pub_type: 杂志文章
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journal_title:Infection and immunity
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doi:10.1128/IAI.65.6.2396-2401.1997
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journal_title:Infection and immunity
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pub_type: 杂志文章
doi:10.1128/IAI.5.4.595-605.1972
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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.68.12.6519-6525.2000
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.40.1.190-197.1983
更新日期:1983-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.16.1.99-106.1977
更新日期:1977-04-01 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
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.23.3.706-710.1979
更新日期:1979-03-01 00:00:00
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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.61.9.3928-3932.1993
更新日期:1993-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.9.3550-3554.1995
更新日期:1995-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.1.117-123.1992
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pub_type: 杂志文章
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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.43.2.600-606.1984
更新日期:1984-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.47.3.605-612.1985
更新日期:1985-03-01 00:00:00
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journal_title:Infection and immunity
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更新日期:2008-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.3.810-816.1989
更新日期:1989-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.45.3.768-774.1984
更新日期:1984-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.24.1.276-281.1979
更新日期:1979-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02810-14
更新日期:2015-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01458-06
更新日期:2007-02-01 00:00:00
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pub_type: 杂志文章
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更新日期:2014-10-01 00:00:00