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1.
Abstract We describe a simplified method for obtaining highly purified flagellin, suitable for biochemical analysis using HPLC-gel permeation. Amino acid composition and N-terminal sequence analyses were performed on flagellins from serologically distinct isolates. The amino acid composition of flagellin from 10 strains was very similar. The N-terminal amino acid sequence is highly conserved. Significant sequence homology was found with flagellin of Bacillus subtilis .  相似文献   
2.
Abstract Using ligand blotting, it was found that partially purified cytolethal distending toxin prepared from and enterotoxigenic strain of Campylobacter jejuni , bound to two peptides of molecular masses of approximately 59 kDa and 45 kDa and to a single peptide of 59 kDa in protein blots prepared from HeLa and CHO cell membranes, respectively. In contrast, labile toxin of Escherichia coli and cholera toxin bound to a single peptide of the same molecular mass (15 kDa) on protein blots prepared from both CHO and HeLa cell crude membranes resolved by gel electrophoresis. This banding pattern was identical using SDS-solubilized membrane, with or without heat treatment, but no band was obtained when reduced (treatment with 2-mercaptoethanol) samples were used for the gel electrophoresis. The differences between receptors of cytolethal distending toxin and cholera toxin/labile toxin were exploited to develop a receptor-based enzyme-linked immunosorbent assay for detection of cytolethal distending toxin which involved the consecutive addition of either solubilized CHO or HeLa membranes, antigen and antibody. This enzyme-linked immunosorbent assay consistently detected crude cytolethal distending toxin diluted up to 16-fold. The receptor-based enzyme-linked immunosorbent assay for detection of cytolethal distending toxin developed in this study is a suitable alternative assay which can be performed easily in laboratories with minimal facilities and, more importantly, the results are available within a few hours as compared to times of up to 5 days in the conventional tissue culture detection of cytolethal distending toxin.  相似文献   
3.
Abstract A combined polymerase chain reaction and restriction endonuclease (RE) enzyme assay was developed to discriminate between Campylobacter coli and Campylobacter jejuni . Amplimers of the FlaA gene obtained by PCR were digested with Alu I and Hin fI to distinguish C. coli from C. jejuni . With Alu I digestion C. jejuni -specific bands were observed at 110, 140 and 160 bp and C. coli -specific bands at 293 and 147 bp. C. jejuni -specific bands of 349 and 109 bp were found by Hin fI digestion but Hin fI did not digest the Fla A amplimer of C. coli . This combined technique is fast and easy to perform, and distinguishes the two campylobacters unequivocally.  相似文献   
4.
From plate cultures of Campylobacter jejuni grown in room air a particulate protein of 62 kDa was isolated by ion-exchange chromatography. The protein had a square shape from the side view but when viewed from the top it had a star-shaped structure. The molecular size of the whole particle determined by gel filtration was 850 kDa which suggested the presence of 14 subunits of 62 kDa in each particle. The N-terminal 37 amino residues showed more than 80% homology with the sequence of these heat shock protein (HSP) 60 homologs of Chlamydia trachomatis, Helicobacter pylori, and Escherichia coli (GroEL). This protein is immunologically cross-reactive with the antiserum for the 60-kDa HSP of Yersinia enterocolitica. Production of the 62-kDa protein increased under heat stress and growth in an aerobic atmospheric environment. From these observations we concluded that the 62-kDa protein is a Campylobacter stress protein (Cj62) which belongs to the HSP 60 family.  相似文献   
5.
肉及肉制品中空肠弯曲菌的污染情况调查   总被引:9,自引:0,他引:9  
我们对辽宁地区肉及肉制品进行弯曲杆菌属检查,发现12.9%(23/177)的样品为弯曲杆菌属阳性.经API Campy鉴定系统鉴定,其中26.1%(6/23)为空肠弯曲菌(C.jejuni)阳性,同时发现1株大肠弯曲菌.该调查证实,辽宁地区进出口的肉及肉制品中,存在空肠弯曲菌的污染,如果销售不当或再加工卫生不良,会对消费者的健康构成潜在威胁.  相似文献   
6.
Similarly to Helicobacter pylori but unlike Vibrio cholerae O1/O139, Campylobacter jejuni is non‐motile at 20°C but highly motile at ≥37°C. The bacterium C. jejuni has one of the highest swimming speeds reported (>100 μm/s), especially at 42°C. Straight and spiral bacterial shapes share the same motility. C. jejuni has a unique structure in the flagellate polar region, which is characterized by a cup‐like structure (beneath the inner membrane), a funnel shape (opening onto the polar surface) and less dense space (cytoplasm). Other Campylobacter species (coli, fetus, and lari) have similar motility and flagellate polar structures, albeit with slight differences. This is especially true for Campylobacter fetus, which has a flagellum only at one pole and a cup‐like structure composed of two membranes.  相似文献   
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Recently there has been an increase in the number of cases reported of Guillain-Barré syndrome (GBS) developed after Campylobacter jejuni infection. To investigate the role of a C.jejuni GroEL-type heat-shock protein (CjHsp60) in the infection and induction of GBS, we examined the antibody level against CjHsp60 in 27 human sera, including GBS and non-GBS patients, by an enzyme-linked immunosorbent assay. Sera from patients with C. jejuni infection, despite the development of GBS, had a higher titer of anti-CjHsp60 antibody than those of patients without the infection and healthy control subjects. The patients with C. jejuni infection followed by GBS had slightly higher levels of this antibody than did the patients with infection who did not develop GBS, but there was no statistical significance. In conclusion, CjHsp60 is found to be one of the major immunogenic antigens in actual C. jejuni infection, but no evidence that supports the direct relationship between this protein and C. jejuni-associated GBS was found in this study.  相似文献   
10.
AIMS: To evaluate the survival of Campylobacter jejuni relative to that of Escherichia coli in groundwater microcosms varying in nutrient composition. METHODS AND RESULTS: Studies were conducted in groundwater and deionized water incubated for up to 470 days at 4 degrees C. Samples were taken for culturable and total cell counts, nutrient and molecular analysis. Die-off in groundwater microcosms was between 2.5 and 13 times faster for C. jejuni than for E. coli. Campylobacter jejuni had the lowest decay rate and longest culturability in microcosms with higher dissolved organic carbon (4 mg l(-1)). Escherichia coli survival was the greatest when the total dissolved nitrogen (12.0 mg l(-1)) was high. The transition of C. jejuni to the coccoid stage was independent of culturability. CONCLUSION: The differences in the duration of survival and response to water nutrient composition between the two organisms suggest that E. coli may be present in the waters much longer and respond to water composition much differently than C. jejuni. SIGNIFICANCE AND IMPACT OF THE STUDY: The data from these studies would aid in the evaluation of the utility of E. coli as an indicator of C. jejuni. This study also provided new information about the effect of nutrient composition on C. jejuni viability.  相似文献   
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