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1.
Enzyme-linked immunosorbent assay for detection of Clostridium botulinum toxin type A. 总被引:11,自引:0,他引:11
The enzyme linked immunosorbent assay using the so-called "double-sandwich technique" has been applied to determine botulinum toxin type A. By this assay, 50-100 mouse ip LD50 of toxin type A can be detected. No cross-reaction occurs with botulinum toxins of other types tested. In all probability this is due to the high specificity of the antiserum prepared against the toxic component of type A toxin. 相似文献
2.
The enzyme-linked immunosorbent assay using the "double-sandwich" technique was utilized to determine Clostridium botulinum type E toxin. With this technique, about 80 mouse intraperitoneal 50% lethal doses of toxin could be detected. Cross-reaction was hardly observed with C. botulinum type A and B toxins. No cross-reaction was observed with culture supernatants of C. botulinum type C or other Clostridium strains. In all probability this was due to the high specificity of the antiserum prepared aginst the toxic component of type E toxin. 相似文献
3.
Enzyme-linked immunosorbent assay for detection of Clostridium botulinum type E toxin. 总被引:2,自引:2,他引:2 下载免费PDF全文
The enzyme-linked immunosorbent assay using the "double-sandwich" technique was utilized to determine Clostridium botulinum type E toxin. With this technique, about 80 mouse intraperitoneal 50% lethal doses of toxin could be detected. Cross-reaction was hardly observed with C. botulinum type A and B toxins. No cross-reaction was observed with culture supernatants of C. botulinum type C or other Clostridium strains. In all probability this was due to the high specificity of the antiserum prepared aginst the toxic component of type E toxin. 相似文献
4.
S Kozaki J Dufrenne A M Hagenaars S Notermans 《Japanese journal of medical science & biology》1979,32(4):199-205
The enzyme-linked immunosorbent assay using different techniques has been applied to determine botulinum type B toxin. With the so-called "sandwich" technique, about 5,000 mouse ip LD50 of type B toxin can be detected. With the "double-sandwich" technique, about 400 mouse ip LD50 of toxin is detected and different commerical antisera are useful. For accurate quantification of botulinum toxins in culture filtrates, addition of EDTA to samples seems to be necessary. Cross-reactivity of the assay depends on the specificity of the antisera against botulinum type B toxin used and is almost eliminated with antiserum prepared against the toxic component of type B toxin. 相似文献
5.
Detection of T-2 toxin in Fusarium sporotrichioides-infected corn by enzyme-linked immunosorbent assay. 总被引:6,自引:6,他引:0 下载免费PDF全文
A competitive enzyme-linked immunosorbent assay was used to screen for T-2 toxin in Fusarium sporotrichioides -infected corn. The assay detected T-2 toxin in diluted methanol extracts of corn samples at concentrations of 0.05 ng/ml. In infected corn samples, enzyme-linked immunosorbent assay and gas-liquid chromatography estimations of T-2 toxin concentrations were similar. 相似文献
6.
Summary The purification and crystallization of type C botulinum toxin along with its physical characteristics are described. The
shape of Clostridium botulinum type C toxin molecule is globular like a pressed ball with a 7.4 nm diameter and a 4.3 urn thickness. The molecular volume
is approximately 185 nl and the molecular weight is 141 000. The toxin molecule is composed of two parts, which are separable
under appropriate conditions. These parts have some differences in the electrophoretic properties, amino acid distribution,
immunological, and functional characteristics.
The toxin molecule can be reconstituted by association of S-S bond between the two chains. The expression of the toxicity
requires that the fragments of the polypeptide chain carrying the necessary information be functionally organized for the
proper development of the specific tertiary structure for active conformation. 相似文献
7.
Difficulties of molecular dissociation of Clostridium botulinum type G progenitor toxin 总被引:1,自引:0,他引:1
Masafumi Nukina Yumi Mochida Sumiko Sakaguchi Genji Sakaguchi 《FEMS microbiology letters》1991,79(2-3):165-170
Clostridium botulinum type G progenitor toxin was chromatographed on DEAE-Sephadex and Q-Sepharose equilibrated with 0.05 M Tris-HCl buffer, pH 8.0, containing 0.2 M urea. The toxin was eluted in a single protein peak from DEAE-Sephadex, but it was eluted in four protein peaks from Q-Sepharose; the third peak was toxic and the others were nontoxic. The third peak, appearing to be the toxic component, had a molecular mass of 150,000. In SDS-polyacrylamide gel electrophoresis, purified type G progenitor toxin migrated in six bands, with molecular masses of 150,000, 140,000, 58,000, 10,800, 10,600, and 10,400. Type G progenitor toxin may be composed of a toxin component with a molecular mass of 150,000 and a nontoxic component in a manner similar to progenitor toxins of other types. Type G toxic component, whether it was reduced or not, migrated in a single band to the same relative positions in SDS-PAGE; type A toxic component reduced with 2-mercaptoethanol migrated in two bands. 相似文献
8.
Sharma SK Ferreira JL Eblen BS Whiting RC 《Applied and environmental microbiology》2006,72(2):1231-1238
An amplified enzyme-linked immunosorbent assay (ELISA) for the detection of Clostridium botulinum complex neurotoxins was evaluated for its ability to detect these toxins in food. The assay was found to be suitable for detecting type A, B, E, and F botulinum neurotoxins in a variety of food matrices representing liquids, solid, and semisolid food. Specific foods included broccoli, orange juice, bottled water, cola soft drinks, vanilla extract, oregano, potato salad, apple juice, meat products, and dairy foods. The detection sensitivity of the test for these botulinum complex serotypes was found to be 60 pg/ml (1.9 50% lethal dose [LD50]) for botulinum neurotoxin type A (BoNT/A), 176 pg/ml (1.58 LD50) for BoNT/B, 163 pg/ml for BoNT/E (4.5 LD50), and 117 pg/ml for BoNT/F (less than 1 LD50) in casein buffer. The test could also readily detect 2 ng/ml of neurotoxins type A, B, E, and F in a variety of food samples. For specificity studies, the assay was also used to test a large panel of type A C. botulinum, a smaller panel of proteolytic and nonproteolytic type B, E, and F neurotoxin-producing Clostridia, and nontoxigenic organisms using an overnight incubation of toxin production medium. The assay appears to be an effective tool for large-scale screening of the food supply in the event of a botulinum neurotoxin contamination event. 相似文献
9.
Evidence for plasmid-mediated toxin and bacteriocin production in Clostridium botulinum type G. 总被引:3,自引:1,他引:2 下载免费PDF全文
A single 81-megadalton plasmid was previously isolated from each of six toxigenic strains of Clostridium botulinum type G (M. S. Strom, M. W. Eklund, and F. T. Poysky, Appl. Environ. Microbiol. 48:956-963, 1984). In this study, nontoxigenic derivatives isolated from each of the toxigenic strains following consecutive daily transfers in Trypticase (BBL Microbiology Systems, Cockeysville, Md.)-yeast extract-glucose broth at 44 degrees C simultaneously ceased to produce type G neurotoxin and to harbor the resident 81-megadalton plasmid. The nontoxigenic derivatives also ceased to produce bacteriocin and lost their immunity to the bacteriocin produced by the toxigenic strains. In contrast, all of the toxigenic isolates continued to carry the resident plasmid and to produce both bacteriocin and type G neurotoxin. This is the first evidence suggesting that the production of neurotoxin and bacteriocin by C. botulinum is mediated by a plasmid. 相似文献
10.
Bluetongue virus: Detection of antiviral immunoglobulin G by means of enzyme-linked immunosorbent assay 总被引:1,自引:0,他引:1
An enzyme-linked immunosorbent assay was developed to detect antiviral IgG in the sere of sheep exposed to bluetongue virus.
It was found that the enzyme-linked immunosorbent assay is a rapid and sensitive method for the detection of anti-bluetongue
virus antibody. Bluetongue virus antigen prepared from extracts of virus infected BHK and Vero cells were equally effective.
Antigen prepared from uninfected cells when used as coating antigen did not bind IgG from either exposed or unexposed animals.
Sera raised against each of the four individual BTV serotypes, 10, 11, 13, and 17, found in the United States reacted equally
with all four bluetongue virus serotype antigen preparations. Thus, any of the four serotypes can be used as the bluetongue
virus antigen for the detection of anti-bluetongue virus antibody in the bluetongue virus-enzymelinked immunosorbent assay
system. Antiviral IgG was readily detectable 6 days postinoculation. The anti-bluetongue virus antibody concentration continued
to increase through the 35-day postinoculation test period. At 35 days postexposure, antibody titers of 1:1,600 to >1:3,200
were found. The rapid and sensitive nature of the bluetongue virus enzyme-linked immunosorbent assay indicates that this system
should significantly extend serological studies on bluetongue virus. 相似文献
11.
12.
This work aimed to evaluate a method to detect the residual ricin in animal tissues. Immunoprecipitation and sandwich enzyme-linked immunosorbent assay (ELISA) were used to detect ricin in the tissues of intoxicated mice. The monoclonal antibodies (Mabs) 4C13 and 3D74 were used to assay the whole ricin molecules via sandwich ELISA. Mab 4C13 was conjugated with Sepharose 4B to capture ricin or ricin A chain by immunoprecipitation. Mice injected intravenously with ricin at the dosage of 5 μg/mouse were killed at different time points after intoxication. The serum, liver, kidney, lung, and intestine were harvested. High levels of ricin were found in serum and liver samples at each poisoning time point by sandwich ELISA, suggesting the possibility of determining ricin intoxication by detecting residual ricin in the serum. However, this method turned out to be ineffective for examining ricin in the kidney, lung, and intestine of poisoned mice. Although the same tissue samples of intoxicated mice were analyzed by immunoprecipitation, positive bands were found. This indicated that some components in the kidney, lung, and intestine could bind with ricin and interfere in its binding activity with the coated antibody. Immunoprecipitation could be used to measure the existence of ricin in these samples. 相似文献
13.
M W Eklund F T Poysky L M Mseitif M S Strom 《Applied and environmental microbiology》1988,54(6):1405-1408
A single 81-megadalton plasmid was previously isolated from each of six toxigenic strains of Clostridium botulinum type G (M. S. Strom, M. W. Eklund, and F. T. Poysky, Appl. Environ. Microbiol. 48:956-963, 1984). In this study, nontoxigenic derivatives isolated from each of the toxigenic strains following consecutive daily transfers in Trypticase (BBL Microbiology Systems, Cockeysville, Md.)-yeast extract-glucose broth at 44 degrees C simultaneously ceased to produce type G neurotoxin and to harbor the resident 81-megadalton plasmid. The nontoxigenic derivatives also ceased to produce bacteriocin and lost their immunity to the bacteriocin produced by the toxigenic strains. In contrast, all of the toxigenic isolates continued to carry the resident plasmid and to produce both bacteriocin and type G neurotoxin. This is the first evidence suggesting that the production of neurotoxin and bacteriocin by C. botulinum is mediated by a plasmid. 相似文献
14.
Effect of water activity and pH on growth and toxin production by Clostridium botulinum type G. 下载免费PDF全文
The combined effect of water activity (aw) and pH on growth and toxin production by Clostridium botulinum type G strain 89 was investigated. The minimum aw at which growth and toxin formation occurred was 0.965, for media in which the pH was adjusted with either sodium chloride or sucrose. The minimum pH (at the optimum aw) for growth and toxin production of C. botulinum type G was found to be 5.6. Optimum conditions for toxin activation were a trypsin concentration of 0.1%, a pH of the medium of 6.5, and an incubation for 45 min at 37 degrees C. These data did not show evidence of heat-labile spores, since a heat shock of 75 degrees C for 10 min did not significantly decrease the spore count of strain 89G in media at pH 7.0 or 5.6. It was frequently observed that cells grown at reduced aw or pH experienced severe morphological changes. 相似文献
15.
16.
Twelve strains of Clostridium botulinum type A and seven strains of Clostridium sporogenes were screened for plasmids by agarose gel electrophoresis of cleared lysates of cells from 5 ml of mid-log-phase culture. Nine type A strains had one or more plasmids of 4.3, 6.8, or 36 megadaltons (MDa); several strains showed a large plasmid of 61 MDa, but it was not consistently recovered. Four C. sporogenes strains had one or more plasmids of 4.3, 5.6 or 36 MDa. Isolates obtained from cultures of plasmid-containing C. botulinum type A strains grown in ionic detergent broth and from spontaneously arising variants were screened both for toxin production and for plasmid content. Toxigenicity of C. botulinum could not be correlated with the presence of any one plasmid. 相似文献
17.
In the culture fluid of a hemagglutinin-positive strain of Clostridium botulinum type C, two toxins of different molecular size, hemagglutinin positive and negative, were separated by sucrose density gradient centrifugation. 相似文献
18.
Observations on toxin and hemagglutinin produced by Clostridium botulinum type C. 总被引:3,自引:0,他引:3 下载免费PDF全文
In the culture fluid of a hemagglutinin-positive strain of Clostridium botulinum type C, two toxins of different molecular size, hemagglutinin positive and negative, were separated by sucrose density gradient centrifugation. 相似文献
19.
Studies of toxin of Clostridium botulinum type D 总被引:5,自引:0,他引:5