Abstract:
:In Brucella abortus, a gene encoding a major cell envelope protein, omp2, is duplicated within a short segment of the large chromosomal DNA. Although both genes contain open reading frames, encoding proteins of high identity, expression from only one, omp2b, has been detected in laboratory-grown B. abortus. In the present study, we wished to determine whether omp2b encodes the previously studied Brucella porin and to characterize the omp2a gene product. Experiments were performed with Escherichia coli transformants expressing either omp2a or omp2b. Our results indicated that both gene products localized to the outer membrane of E. coli. Initial rates of transport of [14C]maltose and growth rates in the presence of maltodextrins of defined size indicated an increased hydrophilic permeability of transformants expressing omp2a. These cells were also shown to grow on maltotetraose, a molecule with a molecular mass of 667 Da. Activity consistent with the formation of pores could not be demonstrated in transformants expressing omp2b. However, Omp2b formed oligomers resistant to heat denaturation up to 70 degrees C in sodium dodecyl sulfate buffer, a property characteristic of bacterial porins. Overall, these results suggest that the omp2a gene product has pore-forming activity and that the omp2b gene encodes the previously characterized Brucella porin.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Marquis H,Ficht TAdoi
10.1128/IAI.61.9.3785-3790.1993subject
Has Abstractpub_date
1993-09-01 00:00:00pages
3785-90issue
9eissn
0019-9567issn
1098-5522journal_volume
61pub_type
杂志文章abstract::Killing of Salmonella minnesota and Salmonella typhimurium S and R strains in serum of nonimmune humans and guinea pigs was drastically reduced in the selective absence of C1q, C1r, Ca2+, C4, or C2, the components of the classical complement pathway. Binding of C1 and C1q to the S form and six different core-deficient...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.37.3.935-939.1982
更新日期:1982-09-01 00:00:00
abstract::Development of hemolytic uremic syndrome (HUS) after infection by Shigella dysenteriae 1 or enterohemorrhagic Escherichia coli has been associated with the production of Shiga toxins (verotoxins). The putative target of Shiga toxins in HUS is the renal microvascular endothelium. This report shows that preincubation of...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.9.3886-3891.1993
更新日期:1993-09-01 00:00:00
abstract::Minicells are small, anucleate cells resulting from aberrant cell divisions at the polar ends of bacilli. We have isolated minicell-producing mutant strains of Shigella flexneri 2a (MC-I) and Shigella dysenteriae 1 (MC-V) after mutagenesis with N-methyl-N'-nitro-N-nitrosoguanidine. Microscopically, broth cultures of M...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.30.1.297-302.1980
更新日期:1980-10-01 00:00:00
abstract::Gram-negative bacterial cells exposed to a complement source may carry membrane attack complexes containing variable numbers of C9 molecules per C5b-8 site. In order to investigate the assembly of this complex, the ability of C9 molecules to bind to C5b-8 complexes was compared with the binding characteristics of C9 f...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.7.2800-2805.1994
更新日期:1994-07-01 00:00:00
abstract::The mechanism by which recombinant murine gamma interferon (rMuIFN-gamma) and bacterial lipopolysaccharide (LPS) activate mouse resident splenic macrophages to inhibit the intracellular growth of the fungus Histoplasma capsulatum was examined. Growth inhibition depended on L-arginine metabolism. The growth inhibitory ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.5.1940-1945.1994
更新日期:1994-05-01 00:00:00
abstract::Platelets aggregate in response to an adhesin and the platelet aggregation-associated protein (PAAP) expressed on the cell surfaces of certain strains of Streptococcus sanguis. We sought to identify the corresponding PAAP receptor and accessory adhesin binding sites on platelets. Since the adhesion(s) of S. sanguis fo...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.9.3628-3633.1995
更新日期:1995-09-01 00:00:00
abstract::A gene encoding a heat-stable enterotoxin (ST) from an Escherichia coli strain isolated from a human with diarrhea was cloned and characterized by nucleotide sequence analysis. The gene was found to be partially homologous to a previously characterized ST gene from an E. coli strain of bovine origin. Hybridization stu...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.39.3.1167-1174.1983
更新日期:1983-03-01 00:00:00
abstract::Heat-labile enterotoxins from Escherichia coli strains of porcine and human origin polymerize on heating to form high-molecular-weight aggregates, "procoligenoids," analogous to procholeragenoid derived from the cholera enterotoxin. This aggregation is accompanied by loss of biological activity (toxicity). Further hea...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.45.2.518-521.1984
更新日期:1984-08-01 00:00:00
abstract::By subcutaneous treatment with an aqueous solution of 6-O-stearoyl-N-acetylmuramyl-L-alanyl-D-isoglutamine [6-O-CH3-(CH2)16-CO-MurNAc-L-Ala-D-isoGln] [referred to here as L18-MDP(Ala)], an augmentation of the resistance of mice to Escherichia coli, Pseudomonas aeruginosa. Staphylococcus aureus, and Candida albicans in...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.37.1.292-300.1982
更新日期:1982-07-01 00:00:00
abstract::In malarial infections of primates, the spleen has been shown to modulate parasite antigen expression on the surfaces of infected erythrocytes. The processes affected include cytoadherence, which is central to the pathophysiology of severe falciparum malaria, and the related phenomenon of rosette formation. In this st...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.6.2225-2228.1992
更新日期:1992-06-01 00:00:00
abstract::The hemolytic and sphingomyelinase C activities of supernatants of cultures of Leptospira interrogans serovar pomona tended to copurify when isoelectric fractionation was carried out. Both activities focused primarily at pH 8.1. Considered in conjunction with other circumstantial evidence, the results led to the concl...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.54.1.262-264.1986
更新日期:1986-10-01 00:00:00
abstract::The abilities of six strains of Mycobacterium bovis strain BCG to replicate in vivo and to cause spleen enlargement in the CDF(1) male mouse were compared. The strains were grown in synthetic medium and harvested soon after complete pellicles were produced on liquid medium. In addition, two freeze-dried commercially a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.8.5.736-742.1973
更新日期:1973-11-01 00:00:00
abstract::The ocular surface is continuously exposed to potential pathogens, including free-living amoebae. Acanthamoeba species are among the most ubiquitous amoebae, yet Acanthamoeba keratitis is remarkably rare. The pathogenesis of Acanthamoeba keratitis is a complex, sequential process. Here we show that Acanthamoeba kerati...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.2.1061-1068.2005
更新日期:2005-02-01 00:00:00
abstract::We found that thiols reduced the amount of cholera toxin produced by Vibrio cholerae 569B in vitro. A sulfhydryl group at least was necessary for the reduction of cholera toxin production by thiols. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.53.3.700-701.1986
更新日期:1986-09-01 00:00:00
abstract::The endothelium is a specific target for Bartonella henselae, and endothelial cell infection represents an important step in the pathogenesis of cat scratch disease and bacillary angiomatosis. Mechanisms of Bartonella-endothelial cell interaction as well as signaling pathways involved in target cell activation were an...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.8.5088-5097.2001
更新日期:2001-08-01 00:00:00
abstract::Several strains of gram-negative bacteria (seven genera, eight species) isolated from patients with urinary tract infections were found to hydrolyze myeloma immunoglobulin A (IgA) protein. Human IgG and IgM and colostrum IgA were not degraded by these organisms. Examination of cleavage digests showed two fragments of ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.43.1.11-13.1984
更新日期:1984-01-01 00:00:00
abstract::Natural antibodies are those immunoglobulin molecules found in mammalian serum that arise in the absence of exposure to environmental pathogens and may comprise an early host defense against invading pathogens. The spirochete Borrelia burgdorferi first encounters natural antibodies when its arthropod vector, Ixodes sc...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.10.6456-6462.2001
更新日期:2001-10-01 00:00:00
abstract::The protective efficacy of Mycobacterium bovis BCG can be markedly augmented by stable integration of Mycobacterium tuberculosis genomic region RD1. BCG complemented with RD1 (BCG::RD1) encodes nine additional proteins. Among them, 10-kDa culture filtrate protein (CFP-10) and ESAT-6 (6-kDa early secreted antigenic tar...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.4.2170-2176.2004
更新日期:2004-04-01 00:00:00
abstract::F1651 and the pyelonephritis-associated pili (Pap) are two members of the type P family of adhesive factors. They play a key role in establishing disease caused by extraintestinal pathogenic Escherichia coli (ExPEC) strains in animals and humans. Both F1651 and Pap are under the control of an epigenetic and reversible...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02510-14
更新日期:2015-05-01 00:00:00
abstract::Treatment of mouse embryo fibroblasts (MEF) grown in vitro with purified staphylococcal exfoliative toxin (ET) increased the concanavalin A (Con A) agglutinability of MEF 3.5-fold over control cells. Possible explanations for this phenomenon were investigated. ET lacked proteolytic activity on denatured casein. Con A,...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.10.6.1260-1265.1974
更新日期:1974-12-01 00:00:00
abstract::The binding of cryptococcal polysaccharide to a non-encapsulated strain of Cryptococcus neoformans was studied. Binding of purified polysaccharide to the yeast was determined by inhibition of phagocytosis and by indirect immunofluorescence techniques. The ability of cryptococcal polysaccharide to prevent phagocytosis ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.16.1.99-106.1977
更新日期:1977-04-01 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::Chlamydia trachomatis is an obligately intracellular bacterial parasite of eucaryotic cells that undergoes a biphasic life cycle within a parasitophorous vacuole (PV) called an inclusion. The parasitophorous vacuolar membrane (PVM) constitutes a barrier between the replicating bacteria and the nutrient-rich environmen...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.3.1088-1094.1997
更新日期:1997-03-01 00:00:00
abstract::The mechanism of adsorption of the Streptococcus mutans enzymes responsible for the synthesis of insoluble dextran-levan to the S. mutans cell-wall binding sites has been studied. Certain characteristics of these binding sites are presented. The adsorption of these enzymes to the cell surface occurred rapidly without ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.9.2.419-429.1974
更新日期:1974-02-01 00:00:00
abstract::Spotted fever group rickettsiae are known to produce distinct plaque phenotypes. Strains that cause lytic infections in cell culture form clear plaques, while nonlytic strains form opaque plaques in which the cells remain intact. Clear plaques have historically been associated with more-virulent species or strains of ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00048-11
更新日期:2011-04-01 00:00:00
abstract::Gender is a significant factor in determining the susceptibility to and severity of pulmonary diseases in both humans and animals. Murine respiratory mycoplasmosis (MRM), due to Mycoplasma pulmonis infection, is an excellent animal model for evaluation of the role of various host factors on the development of acute or...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.5.2865-2871.2001
更新日期:2001-05-01 00:00:00
abstract::The gene encoding the 35-kDa immunogenic Treponema pallidium subsp. pallidum (T. pallidum) membrane protein C, TmpC, was cloned, sequenced, and expressed in Escherichia coli. The deduced amino acid sequence carries on N-terminal signal sequence with a four-amino-acid motif, which is characteristic for bacterial lipopr...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.10.3536-3546.1991
更新日期:1991-10-01 00:00:00
abstract::Free-living amoebae of the genus Acanthamoeba can cause severe and chronic infections in humans, mainly localized in immune privileged sites, such as the brain and the eye. Monocytes/macrophages are thought to be involved in Acanthamoeba infections, but little is known about how these facultative parasites influence t...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00345-16
更新日期:2016-09-19 00:00:00
abstract::The character of the antibody response in the rabbit to Salmonella typhimurium somatic (O) antigen was similar to the response to each of several serotypes of Shigella flexneri O antigens, namely a predominance of production of immunoglobulin M (IgM) antibody. Lipopolysaccharide protein (LPSP) and lipopolysaccharide (...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1970-03-01 00:00:00
abstract::The bacterial pathogen Clostridium difficle synthesizes two high-molecular-weight toxins (A and B), which exhibit toxic effects in vivo and in vitro. Here, we present evidence that the major intracellular targets of these two toxins are the Rho GTPases. Overexpression of RhoA, RhoB, or RhoC GTPases in transfected HeLa...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.10.4063-4071.1995
更新日期:1995-10-01 00:00:00