Abstract:
:We previously showed that cytotoxic necrotizing factor 1 (CNF1) contributes to Escherichia coli K1 invasion of human brain microvascular endothelial cells (HBMEC) and interacts with the receptor on the surface of HBMEC. CNF1 is the cytoplasmic protein, and it remains incompletely understood how CNF1 is secreted across the inner and outer membranes in E. coli K1. In order to investigate the genetic determinants for secretion of CNF1 in E. coli K1, we performed Tn5 mutagenesis screening by applying beta-lactamase as a reporter to monitor secretion of CNF1. We identified a Tn5 mutant that exhibited no beta-lactamase activity in the culture supernatant and in which the mutated gene encodes a ferredoxin gene (fdx). In the fdx deletion mutant, there was no evidence of translocation of CNF1 into HBMEC. Western blot analysis of the fdx deletion mutant revealed that ferredoxin is involved in translocation of CNF1 across the cytoplasmic membrane. The fdx mutant exhibited significantly decreased invasion of HBMEC, similar to the decreased HBMEC invasion observed with the CNF1 mutant. The failures to secrete CNF1 and invade HBMEC of the fdx mutant were restored to the levels of the parent strain by complementation with fdx. These findings demonstrate for the first time that ferredoxin is involved in secretion of CNF1 across the inner membrane in meningitis-causing E. coli K1.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Yu H,Kim KSdoi
10.1128/IAI.00674-09subject
Has Abstractpub_date
2010-02-01 00:00:00pages
838-44issue
2eissn
0019-9567issn
1098-5522pii
IAI.00674-09journal_volume
78pub_type
杂志文章abstract::Swine were infected orally with pure cultures of Treponema hyodysenteriae, and the humoral antibody response was measured by a passive hemolysis test (passive hemagglutination test with the use of complement). Antibody to T. hyodysenteriae was detected as early as 1 week and later on at 4 months after exposure. Howeve...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.14.4.1106-1108.1976
更新日期:1976-10-01 00:00:00
abstract::We have reported that P388D1 cell line murine macrophages stimulated with lipopolysaccharide (LPS) from Actinobacillus actinomycetemcomitans release interleukin-1 (IL-1) inhibitor. The IL-1 inhibitor was purified from conditioned media of P388D1 cells stimulated with A. actinomycetemcomitans LPS for 72 h to homogeneit...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.2.390-397.1994
更新日期:1994-02-01 00:00:00
abstract::Assembly of adherent biofilms is the key mechanism involved in Staphylococcus epidermidis virulence during device-associated infections. Aside from polysaccharide intercellular adhesin (PIA), the accumulation-associated protein Aap and the extracellular matrix binding protein Embp act as intercellular adhesins, mediat...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01142-10
更新日期:2011-06-01 00:00:00
abstract::Alternate modalities for the treatment of Mycobacterium tuberculosis are needed due to the rise in numbers of immunosuppressed individuals at risk for serious disease and the increasing prevalence of multidrug-resistant isolates. Interleukin-12 (IL-12) has been shown to improve immune responses against M. tuberculosis...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.5.2976-2988.2004
更新日期:2004-05-01 00:00:00
abstract::(DBA/N[female] X CBA/2[male])F1 males have been reported to be deficient in producing antibodies against a number of antigens, including carbohydrates (I. Scher, Adv. Immunol. 35:1-71, 1982). We show that F1 male mice, in contrast to females, made less lipopolysaccharide (LPS)-specific antibodies after immunization wi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.5.1209-1214.1988
更新日期:1988-05-01 00:00:00
abstract::Previously, we isolated a high-molecular-weight immunogenic polysaccharide (designated PS) from Pseudomonas aeruginosa immunotype 1 (IT-1). The method which we used was modified to permit the isolation of a similar PS from P. aeruginosa IT-2. This antigen was composed primarily of carbohydrate, had a complex monosacch...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.34.2.461-468.1981
更新日期:1981-11-01 00:00:00
abstract::The fliA gene of Legionella pneumophila encoding the alternative sigma(28) factor was inactivated by introducing a kanamycin resistance cassette. Electron microscopy and Western blot analysis revealed that the fliA mutant strain is aflagellate and expresses no flagellin. Reporter gene assays indicated that the flaA pr...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.3.1604-1608.2002
更新日期:2002-03-01 00:00:00
abstract::Several viruses were categorized on the basis of their ability to spread from cell to contiguous cell and form plaques in the presence of antiviral antibody. Herpes simplex virus, cytomegalovirus, and vaccinia, measles, and foamy viruses were able to spread in the presence of neutralizing antibody, whereas coxsackievi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.14.5.1172-1178.1976
更新日期:1976-11-01 00:00:00
abstract::Immunity to reinfection in the genital tract of female guinea pigs with the agent of guinea pig inclusion conjunctivitis was found to be dependent upon an intact humoral immune response. Cell-mediated immunity in the absence of humoral immunity had no apparent role in resistance to challenge infection. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.39.1.463-465.1983
更新日期:1983-01-01 00:00:00
abstract::Vibrio parahaemolyticus, a gram-negative marine bacterium, is an important pathogen causing food-borne gastroenteritis or septicemia. Recent genome sequencing of the RIMD2210633 strain (a Kanagawa phenomenon-positive clinical isolate of serotype O3:K6) revealed that the strain has two sets of gene clusters that encode...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.74.2.1032-1042.2006
更新日期:2006-02-01 00:00:00
abstract::The mig gene of Streptococcus dysgalactiae, a major bovine mastitis pathogen, encodes two plasma protein-binding receptors, alpha2-macroglobulin (alpha2-M) and immunoglobulin G (IgG). In this study, the mig gene from one S. dysgalactiae isolate was cloned and expressed in Escherichia coli. The IgG receptor region enco...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.10.6030-6037.2001
更新日期:2001-10-01 00:00:00
abstract::The nucleotide sequence of the chromosomal DNA flanking the Actinomyces naeslundii (formerly A. viscosus) T14V type 1 fimbrial structural subunit gene (fimP) was determined. Six open reading frames (ORFs), in the order 5' ORF3, ORF2, ORF1,fimP, ORF4, ORF5, ORF6 3', were identified. ORF1 encoded a protein of 408 amino ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.7.2629-2639.1997
更新日期:1997-07-01 00:00:00
abstract::Both Streptococcus pyogenes and Streptococcus pneumoniae are widely thought to rapidly die outside the human host, losing infectivity following desiccation in the environment. However, to date, all literature investigating the infectivity of desiccated streptococci has used broth-grown, planktonic populations. In this...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01310-13
更新日期:2014-03-01 00:00:00
abstract::Tubercle bacilli failed to grow in iron-void media enriched with solutions of iron-containing transferrin (Tr) or ferritin (F) because these substances do not provide the bacilli with iron, which is essential for their growth. Animal serum and macrophages possessed no iron carrier with an ability to satisfy the need o...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.9.1.34-40.1974
更新日期:1974-01-01 00:00:00
abstract::The heat-labile enterotoxin (LT) of Escherichia coli is localized in the periplasm of the bacterial cell. Growth of an LT-producing strain of E. coli in the presence of bile salts, in concentrations within the range found in the human small intestine, caused leakage of LT into the culture medium. This leakage could be...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.1.168-171.1991
更新日期:1991-01-01 00:00:00
abstract::Preexisting antivector immunity can severely compromise the ability of Salmonella enterica serovar Typhimurium live vaccines to induce protective CD8 T-cell frequencies after type III secretion system-mediated heterologous protein translocation in orally immunized mice. To circumvent this problem, we injected CpG DNA ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00700-09
更新日期:2009-12-01 00:00:00
abstract::Mice injected intravenously with a commercially available extract of Coxiella burnetii prepared for use as the antigen in the complement fixation diagnostic test for Q fever were subsequently resistant to infection with Babesia microti, Babesia rodhaini, and Plasmodium vinckei petteri. The parasites appeared to die in...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.24.2.319-325.1979
更新日期:1979-05-01 00:00:00
abstract::Adherence of blastoconidia to epidermal corneocytes is an early event in Candida colonization and infection of the skin. Pathogenic species adhere more avidly than nonpathogenic species, transform to hyphal growth, and invade the stratum corneum of the skin. Adherence was studied by scanning electron microscopy of exp...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.8.1942-1949.1988
更新日期:1988-08-01 00:00:00
abstract::Diarrhea and amebic liver abscesses due to invasive Entamoeba histolytica infections are an important cause of morbidity and mortality in the developing world. Entamoeba histolytica adherence and cell migration, two phenotypes linked to virulence, are both aberrant in trophozoites deficient in the metallosurface prote...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02490-14
更新日期:2015-02-01 00:00:00
abstract::Colony variants of Neisseria gonorrhoeae differ in their interactions with eucaryotic cells. When gonococci were cultivated with HeLa cell monolayers, the opacity phenotype (Op) became increasingly dominant in the subpopulation of organisms which adhered to the HeLa cells. Once bound, Op organisms displayed very low l...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.54.1.154-160.1986
更新日期:1986-10-01 00:00:00
abstract::In order to evaluate during experimental Trypanosoma brucei infections the potential role of tumor necrosis factor alpha (TNF-alpha) in the host-parasite interrelationship, C57BL/6 TNF-alpha knockout mice (TNF-alpha-/-) as well as C57BL/6 wild-type mice were infected with pleomorphic T. brucei AnTat 1.1 E parasites. I...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.6.3128-3132.1999
更新日期:1999-06-01 00:00:00
abstract::An "immunogenic" ribonucleic acid (Im-RNA) has been extracted from peritoneal exudate (PE) cells of rats that were immunized with sheep erythrocytes (SRBC). Following multiple phenol extractions and deoxyribonuclease treatment, the material obtained from PE cells was eluted from diethylaminoethyl-cellulose at 0.55 M N...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.8.2.215-221.1973
更新日期:1973-08-01 00:00:00
abstract::Monoclonal antibodies were produced against the HAR-13 strain (A) of Chlamydia trachomatis. By an indirect immunofluorescence technique, three clones (1-7, 2-8, 9F) were found to produce antibody that reacted only with serotype A strains. Clone 3-5 produced antibody that cross-reacted with serotypes A, C, H, I, and J....
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.38.3.1273-1278.1982
更新日期:1982-12-01 00:00:00
abstract::Hamster respiratory epithelial cells were cultured in a monolayer format, and 20% of the cells were ciliated. Mycoplasma pneumoniae attached to the epithelial cells in a neuraminidase-specific fashion and induced ciliostasis and cytonecrosis. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.21.1.333-336.1978
更新日期:1978-07-01 00:00:00
abstract::Ehrlichia chaffeensis and Anaplasma phagocytophilum are agents of human monocytic and granulocytic ehrlichioses, respectively. They are extremely sensitive to mechanical stress and are pleomorphic gram-negative bacteria. Membrane incorporation of cholesterol from the eukaryotic host is known to be essential for other ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.9.5324-5331.2003
更新日期:2003-09-01 00:00:00
abstract::Strain superinfection occurs when a second pathogen strain infects a host already infected with a primary strain. The selective pressures that drive strain divergence, which underlies superinfection, and allow penetration of a new strain into a host population are critical knowledge gaps relevant to shifts in infectio...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02537-14
更新日期:2014-12-01 00:00:00
abstract::The recently introduced choleragen-induced rat foot edema model has been employed as a bioassay for evaluating the immunogenicity of three purified preparations containing cholera exo-enterotoxin antigen, choleragen, choleragenoid, and Formalin-treated choleragen (formagen). The results indicated that choleragen evoke...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.1.5.468-473.1970
更新日期:1970-05-01 00:00:00
abstract::We have examined the ability of peptidoglycan (PepG) and lipoteichoic acid (LTA) isolated from Staphylococcus aureus to induce the release of tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), and IL-10 in whole human blood and identified the cellular origins of these cytokines. Both PepG and LTA induced t...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.7.3965-3970.2000
更新日期:2000-07-01 00:00:00
abstract::Mice with a null deletion mutation in the gamma interferon (IFN-gamma) receptor gene were used to study the role of IFN-gamma responsiveness during experimental pulmonary cryptococcosis. Cryptococcus neoformans was inoculated intratracheally into mice lacking the IFN-gamma receptor gene (IFN-gammaR-/-) and into contro...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.3.1788-1796.2005
更新日期:2005-03-01 00:00:00
abstract::Resistance to phagocytosis is a hallmark of virulent Streptococcus pyogenes (group A streptococcus). Surface-bound C5a peptidase reduces recruitment of phagocytes to the site of infection, and hyaluronic acid capsules and/or the M protein limit the uptake of streptococci. In this study the relative impact of M and M-l...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.11.5399-5405.1998
更新日期:1998-11-01 00:00:00