Abstract:
:The Toll-like receptor 5 (TLR5) binding site has been predicted to be in the N terminus of the flagellin molecule. In order to better define the interaction between the N-terminal amino acids of Pseudomonas aeruginosa flagellin and TLR5, site-specific mutations were generated between residues 88 and 97 of P. aeruginosa PAK flagellin as well as outside of this region. The mutant flagellins were expressed in Escherichia coli BL21(plysS), purified by affinity chromatography, and passed through a polymyxin B column to remove contaminating lipopolysaccharide (LPS). Their ability to stimulate interleukin-8 (IL-8) release from A549 cells was examined. The cloned mutated genes were used to complement a PAK fliC mutant in order to test for effects on motility and on IL-8 release by purified flagellar preparations. All the mutations, single or double, in the predicted TLR5 binding region reduced IL-8 signaling to less than 95% of the wild-type flagellin levels, but the single mutation outside the binding region had no effect. Changes made at two amino acid sites resulted in loss/reduction of motility; however, changes made at single sites, i.e., Q83A, L88A, R90A, M91A, L94A, and Q97A, had no effect on motility. The mutated genes encoding two of the motile but poorly signaling flagellins had no compensatory mutations to allow motility. Thus, while it is speculated that pathogen-associated molecular patterns (PAMPs) have evolved in locations that are essential to maintain function, it appears that there is tolerance for at least single amino acid changes in the PAMP of P. aeruginosa flagellin. The purpose of flagellin glycosylation in P. aeruginosa is unknown. In order to examine its role, if any, in signaling an inflammatory response, we used whole flagella from the motile chromosomal mutant strains PAKrfbC and PAO1rfbC, which are defective in flagellin glycosylation. IL-8 release from A549 cells stimulated with nonglycosylated flagellar preparations (having less then 1 picogram of LPS/mug) was significantly reduced compared to their respective wild-type flagellar preparations, indicating a role of flagellar glycosylation in the proinflammatory action of Pseudomonas flagellin. The basis of the latter activity is unknown, since the glycosylation sites are found in the D3 domain of flagellins and the TLR5 binding site is located in the D1 domain. Thus, P. aeruginosa flagellin has evolved additional flagellar signaling mechanisms over that described for Salmonella flagellin.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Verma A,Arora SK,Kuravi SK,Ramphal Rdoi
10.1128/IAI.73.12.8237-8246.2005keywords:
subject
Has Abstractpub_date
2005-12-01 00:00:00pages
8237-46issue
12eissn
0019-9567issn
1098-5522pii
73/12/8237journal_volume
73pub_type
杂志文章abstract::The in vivo role of endogenous interleukin 12 (IL-12) in modulating intrapulmonary growth of Legionella pneumophila was assessed by using a murine model of replicative L. pneumophila lung infection. Intratracheal inoculation of A/J mice with virulent bacteria (10(6) L. pneumophila cells per mouse) resulted in inductio...
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
abstract::Previous studies have shown that a mutant (designated C4) of Streptococcus mutans 6715 wild type (WT) is defective in glucosyltransferase (GTF)-synthesized insoluble glucan and is avirulent in gnotobiotic rats. This study investigated the factors which would render this mutant virulent in gnotobiotic rats. Microbial a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.27.3.915-921.1980
更新日期:1980-03-01 00:00:00
abstract::Of 51 patients with herpes simplex labialis, 50 had detectable interferon (IFN) in samples of lesion vesicle fluid. The median titer of vesicle fluid IFN was 8,200 U. and the range of values was 400 to 63,600 U. The amount of vesicle fluid IFN was correlated with lesion age (r = 0.32, P = 0.024) and vesicle fluid viru...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.36.3.907-910.1982
更新日期:1982-06-01 00:00:00
abstract::Raising the magnesium level from 0.4 to 1.5 mM in a medium containing only amino acids (2.08%), salts, and vitamins increased enterotoxin B production by Staphylococcus aureus S-6 by about 80%. The level of phosphates in the medium was lowered to one-tenth (to 2.87 mM) the original amount without adversely affecting g...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.20.1.158-160.1978
更新日期:1978-04-01 00:00:00
abstract::Brucella abortus is recognized by several Toll-like receptor (TLR)-associated pathways triggering proinflammatory responses that affect both the nature and intensity of the immune response. Previously, we demonstrated that B. abortus-mediated dendritic cell (DC) maturation and control of infection are dependent on the...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01356-12
更新日期:2013-05-01 00:00:00
abstract::Type 14 is one of the common types isolated from patients of all ages with infections caused by Streptococcus pneumoniae. Its capsular polysaccharide (Pn14) is composed of a neutrally charged tetrasaccharide repeat unit. Pn14 does not elicit protective levels of antibodies in infants and children and is a less than op...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.9.3528-3532.1992
更新日期:1992-09-01 00:00:00
abstract::K99 prepared by acid precipitation hemagglutinated guinea pig erythrocytes, whereas K99 prepared by chromatography on diethylaminoethyl-Sephadex did not. K99 purified by either procedure hemagglutinated horse erythrocytes. K99 prepared by acid precipitation contained a second antigen not presnet in the K99 prepared by...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.22.2.555-559.1978
更新日期:1978-11-01 00:00:00
abstract::The biological activity of C-ASWS, an alkali-soluble, water-soluble cell wall antigen isolated from mycelial-phase cells of Coccidioides immitis, was compared with that of a commercial coccidioidin (CDN; Cutter Laboratories); CDN-TS, a toluene-induced lysate of mycelial-phase cells; and spherulin, a spherule-derived e...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.15.3.751-755.1977
更新日期:1977-03-01 00:00:00
abstract::Although Salmonella enterica serovar Typhimurium can undergo phase variation to alternately express two different types of flagellin subunit proteins, FljB or FliC, no biological function for this phenomenon has been described. In this investigation, we constructed phase-locked derivatives of S. enterica serovar Typhi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.5.3021-3030.2001
更新日期:2001-05-01 00:00:00
abstract::During the systemic phase of murine infection with Salmonella enterica serovar Typhimurium, bacterial virulence is correlated with the ability to grow and survive within host macrophages. Salmonella pathogenicity island 2 (SPI-2), encoding a type three secretion system, has emerged as an important contributor to Salmo...
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
abstract::Three-month-old male Crl:CD1(ICR)BR and C3H/HeJ mice were fed chow containing Candida albicans for 14 days, while similar control mice were fed regular food. Stool cultures were done for all mice before and after administration of the special diet. Stool cultures were repeated 48 h, 1 week, and 1 and 3 months after st...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.6.1514-1517.1990
更新日期:1990-06-01 00:00:00
abstract::The 120-kDa rickettsial outer membrane protein (rOmpB) is encoded by a gene with the capacity to encode a protein of approximately 168 kDa. The carboxy-terminal end of the molecule is apparently cleaved to yield 120- and 32-kDa products. Both polypeptides are surface exposed and remain associated with the outer membra...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.1.159-165.1992
更新日期:1992-01-01 00:00:00
abstract::Antiserum and purified immunoglobulin directed against Mycoplasma pneumoniae membrane protein P1 were examined for their influence on mycoplasma viability, metabolism, and cytadsorption. Anti-P1 immunoglobulin inhibited adherence of M. pneumoniae to hamster tracheal rings in vitro by up to 80% and inhibited hemadsorpt...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.39.3.1180-1186.1983
更新日期:1983-03-01 00:00:00
abstract::Salmonella enterica subspecies I serovars are common bacterial pathogens causing diseases ranging from enterocolitis to systemic infections. Some serovars are adapted to specific hosts, whereas others have a broad host range. The molecular mechanisms defining the virulence characteristics and the host range of a given...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.74.1.632-644.2006
更新日期:2006-01-01 00:00:00
abstract::Insertional inactivation of the Streptococcus mutans spaP gene was used to construct an isogenic mutant (834) of strain NG8 (serotype c) which lacked the major cell surface-associated protein referred to as P1 (15). Results of several studies suggest that P1 is involved in the adherence of S. mutans to saliva-coated a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.12.4606-4609.1991
更新日期:1991-12-01 00:00:00
abstract::Normal ICR mice were infected intravenously, intraperitoneally, or aerogenically with Pasteurella multocida strains isolated from a turkey (S68), calf (V90), or rabbit (J20) lung. Both the turkey and calf isolates were highly virulent for mice and multiplied logarithmically in the lungs, liver, and spleen, resulting i...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.39.2.779-784.1983
更新日期:1983-02-01 00:00:00
abstract::Escherichia coli O157:H7 is an important pathogen of humans. Cattle are most frequently identified as the primary source of infection, and therefore, reduction in E. coli O157:H7 prevalence in cattle by vaccination represents an attractive strategy for reducing the incidence of human disease. H7 flagella have been imp...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01452-07
更新日期:2008-06-01 00:00:00
abstract::Bordetella bronchiseptica secreted a hydroxamate siderophore when grown in Fe-depleted medium. A Tn5lac insertion mutant of B. bronchiseptica, DBB22, did not produce this hydroxamate siderophore and was incapable of using lactoferrin as an Fe source. Our data suggest that B. bronchiseptica uses a siderophore for remov...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.6.2698-2702.1993
更新日期:1993-06-01 00:00:00
abstract::Pathogenic leptospires have the ability to survive and disseminate to multiple organs after penetrating the host. Several pathogens, including spirochetes, have been shown to express surface proteins that interact with the extracellular matrix (ECM). This adhesin-mediated binding process seems to be a crucial step in ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00460-06
更新日期:2006-11-01 00:00:00
abstract::Random-bred mice were immunized with a nonliving antigen prepared from mixed-blood forms of Plasmodium berghei, strain NYU-2, in combination with Corynebacterium parvum and/or living BCG. A high proportion of intravenously immunized mice survived virulent challenge, but subcutaneous vaccination was less effective. Vac...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.22.3.798-803.1978
更新日期:1978-12-01 00:00:00
abstract::HbhA of Mycobacterium tuberculosis is a multifunctional binding protein, binding to both sulfated sugars such as heparin and to human complement component C3. HbhA may therefore interact with host molecules and/or host cells during M. tuberculosis infection and play a role in the pathogenesis of this bacterium. The pu...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.12.6751-6760.2002
更新日期:2002-12-01 00:00:00
abstract::The mouse system provides an excellent model for studying host resistance to Naegleria fowleri, the agent of primary amoebic meningoencephalitis. Innate resistance to infection with N. fowleri was examined with respect to infecting dose and the age, sex, and strain of mice. Intravenous inoculation with 10(7) amoebae p...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.20.1.73-77.1978
更新日期:1978-04-01 00:00:00
abstract::Helicobacter pylori infection is thought to be involved in the development of several gastric diseases. Two H. pylori virulence factors (vacuolating cytotoxin A and cytotoxin-associated gene A) reportedly interact with lipid rafts in gastric epithelial cells. The role of Toll-like receptor (TLR)-mediated signaling in ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.05856-11
更新日期:2012-05-01 00:00:00
abstract::Some strains of Streptococcus mutans were found to recognize and bind collagen type I. Binding of 125I-labeled collagen type I was specific in that collagen types I and II, but not unrelated proteins, were able to inhibit binding of the labeled ligand to bacteria. Collagen binding to S. mutans was partially reversible...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.10.4119-4125.1993
更新日期:1993-10-01 00:00:00
abstract::Previous studies indicated that inorganic pyrophosphatase of Ascaris suum (AsPPase) plays an important role in larval survival in the host. Here we describe a precise role for AsPPase in larval molting and development and also describe the potential role of recombinant AsPPase (rAsPPase) in protective immunity to A. s...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.4.1995-2004.2005
更新日期:2005-04-01 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::The identification of genes with increased expression in vivo may lead to the identification of novel or unrecognized virulence traits and/or recognition of environmental signals involved in modulating gene expression. Our laboratory is studying an extraintestinal isolate of Escherichia coli as a model pathogen. We ha...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.10.5306-5314.1999
更新日期:1999-10-01 00:00:00
abstract::In order to further understand Epstein-Barr virus (EBV)-lymphocyte interactions, we investigated a chain of events including: (i) EBV binding to human lymphocyte subpopulations; (ii) the earliest appearance of EBV-determined nuclear antigen (EBNA) in the lymphocytes after EBV infection; and (iii) establishment of cont...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.13.2.303-310.1976
更新日期:1976-02-01 00:00:00
abstract::We produced anti-idiotype antibodies to antibody to lipid A from Eikenella corrodens. The ALA-1 monoclonal antibody (immunoglobulin M [IgM] isotype), which had already been produced in our laboratory (T. Kato, I. Takazoe, and K. Okuda, Infect. Immun. 57:656-659, 1989), had reacted strongly with lipid A from E. corrode...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.2.416-420.1990
更新日期:1990-02-01 00:00:00
abstract::The interactions between Capnocytophaga ochracea ATCC 33596 and Streptococcus sanguis H1, Actinomyces naeslundii PK984, or Actinomyces israelii PK16 are dependent on specific recognitions between heat-sensitive adhesins on C. ochracea and heat-stable structures (probably carbohydrate-containing receptors) on the surfa...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.5.1198-1202.1987
更新日期:1987-05-01 00:00:00