Abstract:
:An enterotoxin produced by Bacteroides fragilis was purified to homogeneity and characterized as to its biological activity and basic molecular properties. Toxin preparations were prepared by growing B. fragilis VPI 13784 in brain heart infusion broth to early stationary phase, immediately precipitating the culture supernatant fluid with 70% ammonium sulfate, and stabilizing the precipitate with the protease inhibitor TPCK (tolylsulfonyl phenylalanyl chloromethyl ketone). The toxin was sequentially purified by anion-exchange chromatography on Q-Sepharose, hydrophobic interaction chromatography on phenyl-agarose, and high-resolution ion-exchange chromatography on Mono Q. The toxin appeared homogeneous as judged by polyacrylamide gel electrophoresis. The estimated molecular weight of the highly purified toxin as determined by gel filtration chromatography on Superose-12 and sodium dodecyl sulfate-polyacrylamide gel electrophoresis is 19,000. It has an isoelectric point of approximately 4.5 and is stable at pHs 5 to 10. The purified toxin is stable at -20 and 4 degrees C and upon freeze-drying, but it is unstable at temperatures above 55 degrees C. It is sensitive to proteinase K and Streptomyces protease but is resistant to trypsin and chymotrypsin. The activity of the purified toxin is neutralized by antiserum to a toxigenic strain of B. fragilis but not by antiserum to nontoxigenic strains. N-terminal amino acid analysis reveal an unambiguous sequence of Ala-Val-Pro-Ser-Glu-Pro-Lys-Thr-Val-Tyr-Val-Ile-Xxx-Leu-Arg-Glu-Asn-Gly- Ser-Thr . The highly purified toxin induced a strong fluid accumulation response in the lamb ileal-loop assay as well as a cytotoxic response (cell rounding) on HT-29 colon carcinoma cells. Thus, the purified toxin can cause both enterotoxic and cytotoxic activities.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Van Tassell RL,Lyerly DM,Wilkins TDdoi
10.1128/IAI.60.4.1343-1350.1992keywords:
subject
Has Abstractpub_date
1992-04-01 00:00:00pages
1343-50issue
4eissn
0019-9567issn
1098-5522journal_volume
60pub_type
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.10.3418-3423.1991
更新日期:1991-10-01 00:00:00
abstract::Protection against colibacillosis in neonatal piglets was obtained by immunization of pregnant dams with procholeragenoid. Procholeragenoid is a stable high-molecular-weight aggregate of cholera toxin formed during the heating of cholera toxin. Procholeragenoid retained approximately 1% of the toxicity of native toxin...
journal_title:Infection and immunity
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doi:10.1128/IAI.35.3.887-894.1982
更新日期:1982-03-01 00:00:00
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abstract::The kinetics of cytotoxic T lymphocyte antigen 4 (CTLA-4) expression on T cells responding to Cryptococcus neoformans and its role in regulating the T-cell response were examined. Using peripheral blood mononuclear cells stimulated with encapsulated or acapsular C. neoformans we showed that (i) the encapsulated strain...
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doi:10.1128/IAI.69.3.1508-1514.2001
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abstract::Staphylococcus aureus is one of the pathogens most frequently isolated in device-related infections. S. aureus is equipped with surface-associated proteins promoting specific binding to matrix molecules. Clumping factor A (ClfA, encoded by clfA) mediates adhesion to fibrinogen. Whereas the contribution of ClfA to path...
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.3.949-954.1991
更新日期:1991-03-01 00:00:00
abstract::Vaccination with recombinant outer surface protein A (OspA) has been shown to protect mice from infection with Borrelia burgdorferi, the Lyme disease agent. To determine whether antibodies to B. burgdorferi proteins other than OspA are involved in protective immunity, antibodies to OspA were removed from protective an...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.2.657-661.1992
更新日期:1992-02-01 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
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.48.3.676-685.1985
更新日期:1985-06-01 00:00:00
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journal_title:Infection and immunity
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更新日期:1995-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.8.2696-2698.1990
更新日期:1990-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.37.2.656-661.1982
更新日期:1982-08-01 00:00:00
abstract::Alpha-toxin, the major cytolysin of Staphylococcus aureus, preferentially attacks human platelets and cultured monocytes, thereby promoting coagulation and the release of interleukin-1 and tumor necrosis factor. Titers of naturally occurring antibodies in human blood are not high enough to substantially inhibit these ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.10.3214-3220.1989
更新日期:1989-10-01 00:00:00
abstract::Legionella pneumophila organisms are able to infect and multiply within the ciliated protozoan Tetrahymena pyriformis. This ability may be associated with virulence, because an attenuated strain of L. pneumophila fails to multiply within this protozoan, whereas a virulent strain increases 10,000-fold in number when co...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.53.3.553-559.1986
更新日期:1986-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.35.3.1032-1040.1982
更新日期:1982-03-01 00:00:00
abstract::Evidence is presented to indicate that Plasmodium berghei merozoites, but not trophozotites, have an antiphagocytic capsule. The capsule appears to form around the developing merozoties of the schizont in the parasitophorous vacuole. Serum from animals immune to P. berghei reacts with this capsule. After reaction with...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.20.3.827-835.1978
更新日期:1978-06-01 00:00:00
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::Ureaplasma urealyticum is a common commensal of the female lower urogenital tract, yet it has been shown to be an important cause of chorioamnion infection, respiratory and central nervous system disease, and death in premature infants. It has been suggested that only certain serovars are capable of producing invasive...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.3.891-898.1995
更新日期:1995-03-01 00:00:00
abstract::Pneumolysin is a 471-amino-acid toxin produced by Streptococcus pneumoniae which has both cytolytic and complement activation properties. We have constructed a derivative of the type 2 S. pneumoniae strain D39 in which the portion of the pneumolysin gene encoding amino acids 55 to 437 has been deleted in-frame. The vi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.2.981-985.1999
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pub_type: 杂志文章
doi:10.1128/IAI.02701-14
更新日期:2015-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.10.4.742-746.1974
更新日期:1974-10-01 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
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journal_title:Infection and immunity
pub_type: 杂志文章
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更新日期:2003-03-01 00:00:00
abstract::Henle 407 and HeLa cells were compared as hosts for Shigella dysenteriae at a low multiplicity of infection. Efficiency of attachment and invasion without centrifugation, as well as selectivity for pathogenic over nonpathogenic S. dysenteriae without Congo red, were much greater for Henle 407 cells than for HeLa cells...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.7.2401-2403.1990
更新日期:1990-07-01 00:00:00
abstract::Four classes of mutants of type III group B streptococcus were isolated by serial subculture of the wild-type strain in the presence of type III-specific rabbit antiserum. Class I mutants no longer synthesized sialic acid but still elaborated the core antigen. Class II mutants maintained the ability to synthesize sial...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.42.1.141-151.1983
更新日期:1983-10-01 00:00:00
abstract::Ninety-six Aeromonas hydrophila isolates were tested for cytotoxin and hemolysin production. Sixty-six (69%) of the isolates were both cytotoxic and hemolytic, whereas the rest produced neither cytotoxin nor hemolysin. No evidence of a separate cytotonic activity could be found in any of the isolates. Cytotoxin activi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.23.3.829-837.1979
更新日期:1979-03-01 00:00:00
abstract::Nitration of protein A with tetranitromethane incompletely blocks its Fc-binding ability for immunoglobulin G when measured by more sensitive methods of immunoprecipitation and when tested in the enzyme-linked immunosorbent assay. In addition, binding of protein A and blockage by nitration is heterogeneous and depends...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.21.2.659-662.1978
更新日期:1978-08-01 00:00:00
abstract::Ocular toxoplasmosis is a potentially blinding intraocular inflammation. The intent of this study was to investigate the role of Fas-FasL interaction in a murine model of acquired ocular toxoplasmosis induced by intracameral inoculation of Toxoplasma gondii. Intraocular inflammation, Fas and FasL expression on lymphoc...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.2.928-935.1999
更新日期:1999-02-01 00:00:00
abstract::Toxic shock syndrome-associated staphylococcal and streptococcal exotoxins were tested for an ability to induce the production of tumor necrosis factor (TNF). Staphylococcal enterotoxins B and C1, along with streptococcal pyrogenic exotoxin A, all induced TNF production in a dose-dependent manner, with production peak...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.1.291-294.1989
更新日期:1989-01-01 00:00:00
abstract::An apparent inhibition of induction of mouse hepatic tryptophan oxygenase by endotoxin has been reported previously, as evidenced by low catalytic activity. This could be due either to decreased tryptophan oxygenase levels or to inactivation of existing enzyme molecules. To resolve this question, the enzyme was quanti...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.8.4.534-539.1973
更新日期:1973-10-01 00:00:00