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1.
C型肉毒梭菌毒素的稳定性研究 总被引:1,自引:0,他引:1
报道了保存肉毒毒素经常会遇到的某些因素对C型肉毒梭菌C6514培养滤液稳定性的影响观察结果。结果表明,提高环境温度及介质酸碱度、日光照射、激烈震荡都能使毒素的毒力下降。甘油或明胶磷酸盐缓冲剂对于保存C型肉毒毒素都是较好的活性稳定剂。含甘油或明胶磷酸盐缓冲剂的毒素在4℃下保存12个月后,毒力的变动甚微。此二法都不需要特殊设备,材料易得,操作简便,比较实用。 相似文献
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对首次自E型肉毒中毒食品中分离到的一株神经毒素原性酪酸梭菌(LCL155)所产生的神经毒素,同E型肉毒梭菌(E153)所产生的神经毒素进行了精制及特性比较,发现(1)两菌神经毒素的分子量,Native-PAGE测试均为320kDa;SDS-PAGE测试则均为147kDa,非毒性非血凝素部分均为128kDa;用胰蛋白酶激活神经毒素后发现两菌神经毒素均由分子量为103kDa的H链和48kDa的L链组成。(2)两菌神经毒素柱层析图像基本一致,但在菌体毒素提取效果及精制效果诸方面,分离的酪酸梭菌却都较差。(3)胰蛋白酶激活试验表明:两菌神经毒素达到最大毒力所需激活时间不等。在相同温度下,分离的酪酸梭菌毒素只需5min,而E型肉毒梭菌毒素却需30min,提示两菌神经毒素激活动力学上存在差异。(4)琼脂双扩散试验结果表明两菌神经毒素的抗原性是一致的,没有发现沉淀线呈交叉或部分交叉现象。 相似文献
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C型肉毒毒素与C型肉毒中毒 总被引:1,自引:1,他引:0
傅思武 《微生物学免疫学进展》1994,22(3):51-54
本文介绍了C型肉毒毒素的纯化、生物学特性,并从流行病学角度对动物C型肉毒中毒的发生、中毒机理及临床表现、诊断、治疗及预防等进行了概述。对近年来C型肉毒毒素在分子水平、作用机理等方面的研究进展做了简要介绍。 相似文献
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王成怀 《微生物学免疫学进展》2009,37(2)
为了纪念兰州生物制品研究所建所75周年,本刊对献身祖国大西北、为生物制品事业作出贡献的科技人员的业绩,组织编写了一批文章,现刊出首篇,以飨读者,并将陆续发表,望关注,提出宝贵意见。 相似文献
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C型肉毒梭菌毒素杀灭高原鼠兔的研究 总被引:8,自引:2,他引:8
本文报道用C型肉毒梭菌毒素杀灭高原鼠兔的试验,冬季灭鼠效果达98%。作为一种新的杀鼠剂,具有毒性强、用量少、成本低、残效期短、无二次中毒、不污染环境、对人畜安全、使用方便等优点。是我国首次用生物毒素灭鼠成功的试验,打开了生物灭鼠的新途径。 相似文献
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从我国东海地区的海泥培养物中,分离出一株厌氧性芽孢杆菌。经细菌学、毒素血清学.细菌代谢产物的气相色谱分析及DNA中G+ct001%测定,鉴定为D型肉毒梭菌,编号为D85501。与国际参考菌株D359对照,D85 501菌株具有D型肉毒梭菌的总特性,还有自身的特点,是D型肉毒梭菌中的一新株,是我国分离的首株D型肉毒梭菌。 相似文献
8.
对小鼠、豚鼠、兔、猫和恒河猴进行了A型肉毒梭菌毒素敏感性的比较,实验发现不同种动物对A型毒素的敏感性有很大不同。其中家兔最敏感,豚鼠次之,小鼠与恒河猴中等敏感度、猫最不敏感。显示出动物对A型毒素的敏感性与动物种类有关而与体重无直接关系。 相似文献
9.
中国的E型肉毒中毒及其病原菌的特点 总被引:2,自引:1,他引:2
本世纪30年代中期,几乎同时在原苏联与美国分别发现海鱼引起的肉毒中毒并认定其病原菌为一新型即E型的肉毒梭菌之后,世界各地也相继发现E型肉毒中毒发生,且多为沿海地区居民因食用处理不当的鱼,鱼子及各种海栖动物肉所导致。而我国的E型肉毒中毒及其病原菌的地理分布状态以及中毒诱因等方面在国际间具有某些独特之处。在我国,除大连新金县罐头鱼引起的一起E型肉毒中毒之外,E型中毒主要发生在海拔4~5千米的青藏高原或远隔海域的东北平原和华北平原;中毒均为食物中毒型,原因食品及发病因素基本上都是生吃冬藏肉或豆谷类发酵食品。我国的E型肉毒梭菌也多分布于黄土高原或内陆平原,而在沿海的泥沙和鱼类中则很少能检出该菌。华北平原微山湖周边几个县发生的3起食物中毒型E型肉毒中毒已经证实均系酪酸梭菌产生的E型神经毒素所引起,并又查明该湖周围土壤中确有E型神经毒素原性酪酸梭菌存在,此乃世界上最早的发现 相似文献
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Many spores (1-60/g) of Clostridium botulinum type F were detected in different containers of honey products of the same brand. Microbiological and physicochemical properties of the contaminated honey were compared with those of the negative one. No difference in pH, hydroxymethyl furfural contents or diastase activity was found between them. The total counts of anaerobes other than C. botulinum and of yeast were also similar, whereas the aerobe counts, which were proportionally related with the C. botulinum counts, were higher in the positive honey than in the negative one. Motile colony-forming Bacillus alvei was predominant among the aerobes. B. alvei stimulated the toxin production by C. botulinum type F in culture medium incubated under aerobic conditions. The high count of C. botulinum in the honey might have been due to the possible stimulation of growth by B. alvei or some other microorganisms at some stage of honey ripening. 相似文献
12.
Alison K. East P.T. Richardson D. Allaway M.D. Collins T.A. Roberts Daphne E. Thompson 《FEMS microbiology letters》1992,96(2-3):225-230
Primers designed to conserved regions of botulinum and tetanus clostridial toxins were used to amplify DNA fragments from non-proteolytic Clostridium botulinum type F (202F) DNA using polymerase chain reaction technology. The fragments were cloned and the complete nucleotide sequence of the gene encoding type F toxin determined. Analysis of the nucleotide sequence demonstrated the presence of an open frame encoding a protein of 1274 amino acids, similar to other botulinum neurotoxins. Upstream of the toxin gene is the end of an open reading frame which encodes the C-terminus of a protein with homology to non-toxic-non-hemagglutinin component of type C progenitor toxin. 相似文献
13.
将F型肉毒梭菌经适宜条件产毒培养后,以硫酸铵盐析和酸沉两种不同工艺制备的F型肉毒毒素,用分段脱毒法脱毒制备类毒素,分别免疫豚鼠、马匹后测定免疫血清抗体效价。结果显示,两种工艺制备的毒素其类毒素都具有较好的免疫原性。 相似文献
14.
Charlotte E Ellisa Marie Hammana Henry Harrisa Rulis de Bruina 《FEMS immunology and medical microbiology》1999,24(3):369-372
Reagents were prepared for use in ELISAs to determine the concentration of the antigenic components of Clostridium botulinum type C and D. The results obtained were compared with the L+dose assay and a good correlation was found between the two assays for measurement of the C and D neurotoxin concentration. These ELISAs were also used to determine the concentration of the neurotoxins in toxoid form. The relationship between the C neurotoxin dose, in toxoid form, and the immune response in guinea pigs could be deduced from the data obtained. The relationship for the D neurotoxin was not that clear, as the same concentration of the antigen resulted in variable potency values. However, these ELISAs can be used to formulate the concentration of the C and D components in the final bivalent vaccine. Replacement of the preliminary potency assay on the monovalent components after production with the in vitro assays will shorten the total production time of the vaccine by about 60 days. The economical and ethical implications are the reduction in the use of animals to evaluate the vaccine. 相似文献
15.
Neurotoxins of Clostridium botulinum are needed in basic neurologic research, but as therapeutic agent for certain neuromuscular disorders like strabism as well. A method for the production and purification of botulinum neurotoxins C and D is reported using a two-step hollow-fiber cross flow filtration and a newly developed chromatographic purification procedure. Hollow-fiber filtration proved to be a rapid and safe concentration and pre-purification step, which can easily be scaled up. The chromatographic purification included hydrophobic interaction, anion exchange and size exclusion chromatography runs. Botulinum neurotoxins C and D could be recovered with an overall yield of 12.6% and 10.6%, respectively. A specific toxicity of 1.86 x 10(7) minimal lethal dose mg(-1) (type C) and 5.26 x 10(7) minimal lethal dose mg(-1) (type D) was determined in the mouse bioassay. 相似文献
16.
Hwang HJ Lee JC Yamamoto Y Sarker MR Tsuchiya T Oguma K 《FEMS microbiology letters》2007,270(1):82-89
The structural genes for strain C-Stockholm (c-st) phage particles, a representative type C toxin-converting phage of Clostridium botulinum, have been determined. First, by determining the N-terminal amino acid sequences of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) bands of c-st phage particles, it became clear that four proteins, 14, 25, 32 and 42 kDa, are the products of the ORFs, cst166, cst165, cst160 and cst164, respectively, of the c-st phage genome. The Western blot analyses reacting these phage bands with an antiphage serum prepared previously indicated that the products of cst165 and cst160 are the main proteins of the phage particles. Then, six candidates for the phage structural proteins, including cst165 and cst160 gene products, were prepared as recombinant proteins. Also, the protein corresponding to the cst164 gene product was excised from SDS-PAGE gels. The antibodies against these seven proteins were prepared in rabbits, and finally, the reaction of these antibodies to the c-st phage particles was analyzed by electron microscopy. It was concluded that a sheath protein and a head protein of the c-st phage are the products of genes cst160 and cst165, respectively, and that these two proteins are conserved in the other three converting phages, but not in the nonconverting phage. 相似文献
17.
将C型肉毒梭菌经适宜条件的产毒培养后纯化,并进行相关鉴定。制备的C型肉毒毒素用分段脱毒法脱毒,并进行类毒素保护力的初步研究。以不同蛋白含量C型肉毒类毒素免疫小鼠后攻毒,结果显示,蛋白含量为0.625μg的类毒素免疫2针或蛋白含量为1.25μg的类毒素免疫1针均可保护50LD50的C型肉毒毒素攻击。蛋白含量为5μg的C型肉毒类毒素与福氏不完全佐剂配制的抗原免疫小鼠3次所得抗血清的保护力(Anti LD50/ml)为4.3×104。说明用该纯化工艺制备的C型肉毒类毒素具有很好的免疫原性,作为抗原成分用于C型肉毒疫苗和C型肉毒抗毒素的研究和生产具有较好的应用潜力。 相似文献
18.
Abstract Clostridium botulinum type E derivative toxin directly bound to gangliosides GT1b , GD1a , and GQ1b but not to GM1 or GD1b at pH 5.0 or above, At the same pH values, it bound to negatively charged phospholipids but not to noncharged ones. At pH 4.0, it bound to any of gangliosides and phospholipids including GM1 , GD1a , and non-charged phospholipids. It bound to ceramide, a hydrophobic component of ganglioside and also to sphingomyelin, a phospholipid containing a ceramide moiety, only at pH 4.0. It bound to ceramide and sphingomyelin less firmly than to other phospholipids at pH 4.0. We assume that botulinum toxin adheres to the neural cell surface mainly by sialic acid-specific and charge-dependent binding possibly aided by nonspecific hydrophobic(toxin)-hydrophobic(lipids, mainly phospholipids) interaction. 相似文献
19.
A型肉毒神经毒素(BoNT/A)基因序列分析及其B细胞表位预测 总被引:2,自引:0,他引:2
比较GenBank中4个不同毒株的A型肉毒神经毒素(BoNT/A)的基因组序列,发现其基因序列的一致性高迭92.2%-99.9%。基于保守性高的BoNT/A氨基酸序列,根据BioSun和LaserGene软件包中的表住分析相关参数,辅以对BoNT/A蛋白的二级结构的分析,综合预测BoNT/A的B细胞表位。结果表明,BoNT/A轻链的142-150、284-292区段,轻链的284-292,重链的440-450、465-480、538-549、699-710、751-760、1087-1095、1224-1231、1263-1270区段是B细胞表位优势区的可能性较大。多参数方案井结合不同软件综合预测BoNT/A蛋白的B细胞表位,为进一步实验鉴定BoNT/A的B细胞表位及其多表位疫苗设计和研究奠定了基础。 相似文献
20.
Shunji Kozaki Yasuhiro Oga Yoichi Kamata Genji Sakaguchi 《FEMS microbiology letters》1985,27(2):149-154
Abstract Clostridium botulinum type B and E derivative toxins were activated with lysyl endopeptidase or endoproteinase Lys-C, which splits only the bond involving the carboxyl group of a lysine residue. Type B toxin was more efficiently activated with lysyl endopeptidase; type E toxin was more efficiently activated with trypsin. Type B toxin was split by the lysine-specific protease into 2 fragments of molecular sizes indistinguishable from those induced with trypsin. Type E toxin was split by the same protease into 3 fragments, 2 of which had M r identical to those obtained with trypsin, the other having an M r less than that of the heavy chain but greater than that of the light chain. These results attest that both activation and nicking of type B and E derivative toxins are ascribable to cleavage, not of an arginyl, but of a lysyl bond. 相似文献