Abstract:
:We have previously identified mgrA (rat) as a regulator of autolysis in Staphylococcus aureus. Besides its effect on autolytic activity, we recently found alterations in the expression of regulator and target virulence genes in the mgrA mutant. Northern analysis and transcription fusion assays showed that inactivation of mgrA has led to the downregulation of RNAIII of agr and hla and upregulation of sarS and spa. Although both SarA and agr are activators of alpha-hemolysin and a repressors of protein A synthesis, we found that the transcription of sarA was not affected in the mgrA mutant and vice versa, indicating that MgrA likely regulates hla and spa in a SarA-independent manner. Previously we have shown that SarT, a SarA homolog, is a repressor of hla and an activator of spa, presumably by activating SarS, however, analysis of the double sarT mgrA mutant for hla and spa transcription indicated that the mgrA-mediated effect is not mediated via sarT. Our results further demonstrated that the mgrA gene product regulates hla and spa expression in a dual fashion, with the first being agr dependent and the second agr independent. In the agr-independent pathway, MgrA binds directly to hla and the sarS promoter to modulate alpha-hemolysin and protein A expression. Thus, our studies here have defined the nature of interaction of mgrA with other regulators such as agr, sarS, and sarT and its role in regulating hla and spa transcription within the virulence regulatory network of S. aureus.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Ingavale S,van Wamel W,Luong TT,Lee CY,Cheung ALdoi
10.1128/IAI.73.3.1423-1431.2005keywords:
subject
Has Abstractpub_date
2005-03-01 00:00:00pages
1423-31issue
3eissn
0019-9567issn
1098-5522pii
73/3/1423journal_volume
73pub_type
杂志文章abstract::Engerotoxins isolated from Vibrio cholerae and toxigenic Escherichia coli cause permeability alterations in rabbit skin. Firm induration and erythema are observed within 18 to 24 h, and visualization of the reaction may be enhanced by intravenous injection of Pontamine sky blue dye. Two skin permeability factors (PF) ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.14.3.671-679.1976
更新日期:1976-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.9.2274-2280.1987
更新日期:1987-09-01 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: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.00441-13
更新日期:2013-10-01 00:00:00
abstract::Salmonella enterica serovar Typhimurium, similar to various facultative intracellular pathogens, has been shown to respond to the hostile conditions inside macrophages of the host organism by inducing stress proteins, such as DnaK. DnaK forms a chaperone machinery with the cochaperones DnaJ and GrpE. To elucidate the ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.3.1364-1373.2004
更新日期:2004-03-01 00:00:00
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journal_title:Infection and immunity
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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
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doi:10.1128/IAI.01497-15
更新日期:2016-03-24 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.50.2.442-448.1985
更新日期:1985-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.2.774-781.2004
更新日期:2004-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.10.5742-5748.2000
更新日期:2000-10-01 00:00:00
abstract::Lipopolysaccharides (LPS), either in the free form or complexed to CD14, a LPS receptor, are elicitors of the immune system. Lactoferrin (Lf), a LPS-chelating glycoprotein, protects animals against septic shock. Since optimal protection requires administration of Lf prior to lethal doses of LPS, we hypothesized that i...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.12.6519-6525.2000
更新日期:2000-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.6.3187-3194.2004
更新日期:2004-06-01 00:00:00
abstract::Rinderpest virus infection was shown to induce marked suppression of both humoral antibody response and cell-mediated immunity in rabbits. The virus exhibited a suppressive effect on primary antibody response as indicated by a decrease in numbers of plaque-forming cells (immunoglobulin [Ig]M) and hemagglutinating anti...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.9.2.206-211.1974
更新日期:1974-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.12.3863-3868.1989
更新日期:1989-12-01 00:00:00
abstract::In vivo expression of pili by Escherichia coli in the urine of 41 adults with lower urinary tract infections was analyzed by immunostaining with polyclonal antiserum to type 1 and P pili. Type 1 pili were detected in 31 of 41 urine specimens, while P pili were detected in 6 of 18 specimens. The piliation status of bac...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.6.1656-1662.1989
更新日期:1989-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.4.1684-1693.2002
更新日期:2002-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00135-18
更新日期:2018-06-21 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.4.1461-1466.1996
更新日期:1996-04-01 00:00:00
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pub_type: 杂志文章
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更新日期:2004-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.10.3360-3365.1991
更新日期:1991-10-01 00:00:00
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journal_title:Infection and immunity
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abstract::Stimulation of the rabbit reticuloendothelial system with viable Mycobacterium bovis (strain BCG), and other agents, had no effect on the development of syphilitic lesions after intradermal or intravenous inoculation with graded doses of Treponema pallidum (virulent Nichol's strain; mean infective doses less than 10)....
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.12.5.1029-1036.1975
更新日期:1975-11-01 00:00:00
abstract::Group A streptococcal pyrogenic exotoxins A, B, and C (also known as scarlet fever toxins and erythrogenic toxins) were evaluated for relatedness to another streptococcus-derived lymphocyte mitogen, blastogen A. Streptococcal pyrogenic exotoxin A and blastogen A were immunologically cross-reactive and shared the same ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.6.1865-1867.1989
更新日期:1989-06-01 00:00:00
abstract::Total and insoluble dextransucrase activities were measured in cell-associated and supernatant fractions of Streptococcus mutans GS-5 grown in several media. Although the amount of cell-associated and supernatant activity varied greatly as a function of medium, the total activity appeared constant. The distribution of...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.18.3.629-635.1977
更新日期:1977-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.3.1.187-188.1971
更新日期:1971-01-01 00:00:00
abstract::The proinflammatory cytokine tumor necrosis factor alpha (TNF-alpha) induces lethal hepatitis when injected into D-(+)-galactosamine-sensitized mice on the one hand or systemic inflammatory response syndrome (SIRS) in normal mice on the other hand. We studied whether serum amyloid P component (SAP), the major acute-ph...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.9.5026-5029.2000
更新日期:2000-09-01 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:2007-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.05048-11
更新日期:2011-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00778-15
更新日期:2015-11-01 00:00:00
abstract::Genomics revealed the sequence of 3924 genes of the H37Rv strain of Mycobacterium tuberculosis. Proteomics complements genomics in showing which genes are really expressed, and here we show the expression of six genes not predicted by genomics, as proved by two-dimensional electrophoresis and matrix-assisted laser des...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.69.9.5905-5907.2001
更新日期:2001-09-01 00:00:00