Abstract:
:A heterogeneous subset of extraintestinal pathogenic Escherichia coli (ExPEC) strains, referred to as uropathogenic E. coli (UPEC), causes most uncomplicated urinary tract infections. However, no core set of virulence factors exists among UPEC strains. Instead, the focus of the analysis of urovirulence has shifted to studying broad classes of virulence factors and the interactions between them. For example, the RTX nonfimbrial adhesin TosA mediates adherence to host cells derived from the upper urinary tract. The associated tos operon is well expressed in vivo but poorly expressed in vitro and encodes TosCBD, a predicted type 1 secretion system. TosR and TosEF are PapB and LuxR family transcription factors, respectively; however, no role has been assigned to these potential regulators. Thus, the focus of this study was to determine how TosR and TosEF regulate tosA and affect the reciprocal expression of adhesins and flagella. Among a collection of sequenced UPEC strains, 32% (101/317) were found to encode TosA, and nearly all strains (91% [92/101]) simultaneously carried the putative regulatory genes. Deletion of tosR alleviates tosA repression. The tos promoter was localized upstream of tosR using transcriptional fusions of putative promoter regions with lacZ. TosR binds to this region, affecting a gel shift. A 100-bp fragment 220 to 319 bp upstream of tosR inhibits binding, suggesting localization of the TosR binding site. TosEF, on the other hand, downmodulate motility when overexpressed by preventing the expression of fliC, encoding flagellin. Deletion of tosEF increased motility. Thus, we present an additional example of the reciprocal control of adherence and motility.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Engstrom MD,Alteri CJ,Mobley HLdoi
10.1128/IAI.01608-14subject
Has Abstractpub_date
2014-09-01 00:00:00pages
3644-56issue
9eissn
0019-9567issn
1098-5522pii
IAI.01608-14journal_volume
82pub_type
杂志文章abstract::Although there appears to be little if any role for specific antibodies in protection against intracellular bacteria, such as the model pathogen F. tularensis live vaccine strain (LVS), the role of B cells themselves in primary and secondary infection with such bacteria has not been examined directly. We show here tha...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.11.6002-6007.1999
更新日期:1999-11-01 00:00:00
abstract::The adherence of Treponema denticola GM-1, TD-4, and MS25 to human gingival fibroblasts (HGFs) was studied to serve as an introduction to investigations into the interactions of these oral bacteria with human host cells. Under both aerobic (5% CO2) and anaerobic (85% N2 plus 10% H2 plus 5% CO2) environments, the inter...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.6.1720-1729.1990
更新日期:1990-06-01 00:00:00
abstract::Nontypeable Haemophilus influenzae (NTHi) causes repeated respiratory infections in patients with chronic lung diseases. These infections are characterized by a brisk inflammatory response which results in the accumulation of polymorphonucleated cells in the lungs and is dependent on the expression and secretion of pr...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.8.4430-4440.2000
更新日期:2000-08-01 00:00:00
abstract::A better knowledge on how immune responses are initiated in mucosal tissues would facilitate the design of new mucosal vaccines, as well as improve our understanding on host defense against infection. We investigated the mechanisms of adjuvanticity of the Mycoplasma-derived macrophage-activating 2-kDa lipopeptide (MAL...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.12.6978-6986.2004
更新日期:2004-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.32.1.111-117.1981
更新日期:1981-04-01 00:00:00
abstract::Helicobacter pylori has been directly linked with active chronic gastritis, peptic ulceration, and gastric adenocarcinoma in humans. Although a substantial portion of the human population is colonized with H. pylori, the patterns of transmission of the organism remain in doubt, and reservoir hosts have not been identi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.6.2367-2374.1994
更新日期:1994-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02086-05
更新日期:2006-06-01 00:00:00
abstract::Intestinal mucus is postulated to play a role in preventing colonization of the gastrointestinal tract by microbial pathogens. To evaluate the ability of both crude mucus and purified mucin, a glycoprotein of goblet cell origin, to inhibit mucosal adherence of enteric pathogens, we examined whether mucus and mucin der...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.9.2437-2442.1988
更新日期:1988-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.8.5010-5015.2001
更新日期:2001-08-01 00:00:00
abstract::Serum antibody responses to toxic shock syndrome (TSS) toxin 1 (TSST-1) and staphylococcal enterotoxins A, B, and C were determined by western blot (immunoblot) analysis of acute- and convalescent-phase paired sera from 18 TSS- and 31 non-TSS-associated Staphylococcus aureus infections. Compared with non-TSS cases, se...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.1.231-234.1989
更新日期:1989-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.7.2952-2959.1993
更新日期:1993-07-01 00:00:00
abstract::Pathogenic strains of Yersinia spp. inject a set of Yop effector proteins into eukaryotic cells by using a plasmid-encoded type III secretion system. In this study, we analyzed the inflammatory response of human umbilical vein endothelial cells (HUVECs) after infection with different Yersinia enterocolitica strains. W...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.7.3510-3520.2002
更新日期:2002-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.14.6.1315-1321.1976
更新日期:1976-12-01 00:00:00
abstract::Enteroaggregative Escherichia coli (EAEC) is an emerging cause of diarrheal illness. Clinical data suggest that diarrhea caused by EAEC is predominantly secretory in nature, but the responsible enterotoxin has not been described. Work from our laboratories has implicated a ca. 108-kDa protein as a heat-labile enteroto...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.7.3155-3163.1998
更新日期:1998-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.38.1.53-57.1982
更新日期:1982-10-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01190-06
更新日期:2007-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00025-11
更新日期:2011-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.18.3.775-779.1977
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
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更新日期:2008-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.5.1057-1060.1988
更新日期:1988-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.11.6310-6318.2002
更新日期:2002-11-01 00:00:00
abstract::Vibrio cholerae normally inhabits aquatic habitats but can cause a severe diarrheal illness in humans. Its arsenal of virulence factors includes a secreted hemagglutinin (HA) protease. An HA protease-deficient mutant of V. cholerae was isolated and designated E7946 mpc. E7946 mpc was found to contain a point mutation ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.5.2571-2576.2003
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.70.10.5870-5872.2002
更新日期:2002-10-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01704-07
更新日期:2008-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.74.1.729-733.2006
更新日期:2006-01-01 00:00:00
abstract::Three MudJ prototrophs demonstrated that intracellular replication is a Salmonella virulence trait (K. Y. Leung and B. B. Finlay, Proc. Natl. Acad. Sci. USA, 88:11470-11474, 1991). mutS and mutH are disrupted in mutants 3-11 and 12-23, and ssaQ is disrupted in mutant 17-21. Further analysis revealed that loss of Salmo...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.4.2247-2252.2003
更新日期:2003-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.6.2295-2299.1996
更新日期:1996-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00369-12
更新日期:2012-09-01 00:00:00
abstract::Moraxella catarrhalis expresses surface receptor proteins that specifically bind host transferrin (Tf) and lactoferrin (Lf) in the first step of the iron acquisition pathway. Acute- and convalescent-phase antisera from a series of patients with M. catarrhalis pulmonary infections were tested against Tf and Lf receptor...
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
abstract::Legionella pneumophila multiplied rapidly in guinea pig and rat alveolar macrophages but failed to grow when phagocytic activity was inhibited by pretreatment with 0.5 or 1.0 microgram of cytochalasin D per ml. Attachment was not inhibited by cytochalasin D. No extracellular multiplication occurred when L. pneumophila...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.51.1.31-36.1986
更新日期:1986-01-01 00:00:00