Abstract:
:The type III secretion system (TTSS) of Pseudomonas aeruginosa is induced in vivo upon contact with eukaryotic cells and in vitro by calcium depletion in culture medium. We have observed a previously identified protein, PsrA, necessary for full activation of TTSS gene expression in P. aeruginosa. Electrophoretic mobility shift assays showed that recombinant PsrA could bind to the exsCEBA promoter region. A mutant with a deletion in the psrA gene was constructed. Using transcriptional fusions, we demonstrated that PsrA is required for the full activation of transcription of the TTSS regulatory operon exsCEBA and effector exoS, although the deletion mutant still responded to calcium depletion, to serum, and to host cell contact. The psrA mutant showed a marked decrease in the secretion of the type III effectors and weak resistance to phagocyte-like PLB-985 cells. The defect in TTSS transcription and secretion in the psrA mutant could be complemented by expression in trans of psrA. PsrA was previously identified as a transcriptional activator of RpoS, a central regulator during stationary phase. We confirmed with our strain that RpoS has a negative effect on TTSS gene expression. Taken altogether, these results suggest that PsrA is a newly identified activator that is involved in the expression of the TTSS by enhancing the exsCEBA transcriptional level.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Shen DK,Filopon D,Kuhn L,Polack B,Toussaint Bdoi
10.1128/IAI.74.2.1121-1129.2006keywords:
subject
Has Abstractpub_date
2006-02-01 00:00:00pages
1121-9issue
2eissn
0019-9567issn
1098-5522pii
74/2/1121journal_volume
74pub_type
杂志文章abstract::Isolated Bacteroides gingivalis 2561 vesicles aggregated suspensions of Actinomyces viscosus and Actinomyces naeslundii of all taxonomy clusters. Vesicles bound near A. viscosus cell walls and among its surface fibrils. Tritiated vesicles bound slightly better to saliva-coated hydroxyapatite (SHA) than to SHA coated w...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.5.1618-1620.1989
更新日期:1989-05-01 00:00:00
abstract::Two hybrid clones producing monoclonal antibodies (MAbs) raised against the purified enterotoxic hemolysin-phospholipase C (HlyPC) bifunctional molecule of a Vibrio cholerae O139 strain were used to study its enterotoxicity in relation to its hemolytic and enzymatic activities. Fab fragments of MAbs from ascites produ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.8.3974-3977.1998
更新日期:1998-08-01 00:00:00
abstract::Although protective immunity in C57BL/6 mice induced by a single dose of the radiation-attenuated schistosome vaccine is believed to be mediated by Th1-type immune responses, we here report that in BALB/c mice protection can also depend upon signaling via the interleukin-4 (IL-4) receptor which conventionally governs ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.1.228-236.2001
更新日期:2001-01-01 00:00:00
abstract::On incubation of rabbit polymorphonuclear leukocytes with the S component of staphylococcal leukocidin at 37 degrees C, the 3H-labeled methyl group of S-adenosyl[methyl-3H]methionine was rapidly incorporated into phospholipid. Subsequently, the methylated phosphatidylcholine was degraded by activated phospholipase A2....
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.50.1.142-145.1985
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.00648-09
更新日期:2009-12-01 00:00:00
abstract::Cross-reactive humoral immune responses between antigens of different developmental stages of the worm Schistosoma mansoni have previously been demonstrated. In contrast, information on antigenic cross-reactivity at the T-cell level is still very sparse. The present study examined the cross-reactive T-cell responses t...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.9.3237-3242.1991
更新日期:1991-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00449-08
更新日期:2009-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.4.1478-1479.1994
更新日期:1994-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00518-09
更新日期:2009-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.9.3309-3315.1995
更新日期:1995-09-01 00:00:00
abstract::Mycobacterium marinum grows at an optimal temperature of 33 degrees C, far lower than that for M. tuberculosis. Consequently, M. marinum infection of mammals is restricted largely to the cooler surfaces of the body, such as the extremities, but it causes a systemic infection in a large number of poikilothermic animals...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.2.767-773.1997
更新日期:1997-02-01 00:00:00
abstract::Advanced human periodontitis is considered to be a B-cell lesion, but the cellular infiltrate contains several cell types, the distribution of which has not been determined. This experiment was designed to characterize and identify the immunocompetent cells on histological sections and in eluates from diseased human g...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.41.1.365-374.1983
更新日期:1983-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.5.3.311-318.1972
更新日期:1972-03-01 00:00:00
abstract::Cryptococcus neoformans is surrounded by an antiphagocytic polysaccharide capsule whose primary constituent is glucuronoxylomannan (GXM). Three prominent structural features of GXM are single xylosyl and glucuronosyl side chains and O acetylation of the mannose backbone. Isogenic pairs of O-acetyl-positive and O-acety...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.5.2868-2875.2003
更新日期:2003-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.6.2541-2543.1992
更新日期:1992-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.6.2396-2401.1997
更新日期:1997-06-01 00:00:00
abstract::The enteric pathogens enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli employ a type 3 secretion system (T3SS) to manipulate the host inflammatory response during infection. Previously, it has been reported that EPEC, in a T3SS-dependent manner, induces an early proinflammatory response through a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02131-14
更新日期:2014-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.2.882-890.2003
更新日期:2003-02-01 00:00:00
abstract::Chlamydia trachomatis is a strict human pathogen producing infections that cause medically important chronic inflammatory diseases, such as blinding trachoma and tubal factor infertility. Isolates exist as serotypes that fall into distinct biologic and pathological groups corresponding to differences in infection tiss...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.12.7063-7072.2004
更新日期:2004-12-01 00:00:00
abstract::Arg-gingipain (Rgp) and Lys-gingipain (Kgp) are Porphyromonas gingivalis cysteine proteinases implicated as major virulence factors in pathologies of periodontitis. We purified a 660-kDa cell-associated gingipain complex existing as a homodimer of two catalytically active monomers which comprises their catalytic and a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.2.883-893.2005
更新日期:2005-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.1.64-70.1988
更新日期:1988-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.7.3822-3829.2000
更新日期:2000-07-01 00:00:00
abstract::The response of the intracellular pathogen Rhodococcus equi to H(2)O(2) treatment, a situation potentially encountered after the oxidative burst of alveolar macrophages, was analyzed. Compared to other bacteria, including Deinococcus radiodurans, R. equi showed exceptionally high resistance to this stress. A proteomic...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.7.3768-3776.2002
更新日期:2002-07-01 00:00:00
abstract::Mice with disrupted beta 2-microglobulin (beta 2m-/-), I-A (class II-/-), or CD4 (CD4-/-) genes were examined for their capacity to resolve Chlamydia trachomatis genital tract infection. C57BL/6 and beta 2m-/- mice resolved infection similarly and were culture negative by 4 to 5 weeks following infection. Conversely, ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.12.4661-4668.1995
更新日期:1995-12-01 00:00:00
abstract::B-cell-deficient C57B1/6J mice (suppressed from birth with goat anti-mu) and controls (treated from birth with normal goat serum) were infected with Trypanosoma rhodesiense. There was a significant (P less than 0.01) decrease in duration of survival of the mu-suppressed mice compared with that of controls. Whereas bot...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.18.2.434-438.1977
更新日期:1977-11-01 00:00:00
abstract::Addition of a monoclonal antibody which binds the Cryptococcus neoformans capsule to suspensions of human monocytes, T lymphocytes, and cryptococcal cells (i) enhances interleukin-1beta (IL-1beta), tumor necrosis factor alpha, and IL-2 production; (ii) reduces IL-10 secretion; and (iii) promotes T-cell proliferation. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.3.1244-1247.1998
更新日期:1998-03-01 00:00:00
abstract::In mammals, the natural resistance-associated macrophage protein 1 gene, Nramp1, plays a major role in resistance to mycobacterial infections. Chesapeake Bay striped bass (Morone saxatilis) is currently experiencing an epizootic of mycobacteriosis that threatens the health of this ecologically and economically importa...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.3.1626-1636.2004
更新日期:2004-03-01 00:00:00
abstract::Immunization with avirulent Salmonella typhimurium strain SL3235, a smooth, aroA- derivative, was shown to induce high levels of resistance to challenge with virulent S. typhimurium in innately hypersusceptible C3H/HeJ mice and inherently resistant C3H/HeNCrlBR mice. Strain SL3235 is one of a class of avirulent aroA- ...
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
abstract::Immune responses of mice to Streptococcus mutans serotype c were analyzed by means of the enzyme-linked immunospot assay to determine the predominant specificities of the antibodies developed. In general, the numbers of splenic antibody-secreting cells correlated with serum antibody levels. A low dose (10(8) CFU) of k...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.53.2.317-323.1986
更新日期:1986-08-01 00:00:00
abstract::Immunocompromised patients are more susceptible to recurrent nontyphoidal Salmonella (NTS) bacteremia. A key manifestation of HIV infection is the loss of CD4 T cells, which are crucial for immunity to Salmonella infection. We characterized the consequences of CD4 T cell depletion in mice where virulent Salmonella est...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00417-20
更新日期:2020-12-15 00:00:00