查询词典 bacterial toxin

The principal purpose of this study is to set up the isolation methods for diphtheria toxin expressed by genes, to purify the toxin with complete biological activities, and to make researches on its toxicities. In the experiments, the target gene was inserted into the cloning vectors--pET22b, then the vectors were introduced into host cells -BL21(DE3). The expression of the toxin was induced by addition of IPTG. The expression products were purified by His-6 label affinity chromatography. Then the diphtheria toxin expressed was transferred to PVC membrane using semidry blotter to determine the amino acid sequence of N-terminal. The "nicked" diphtheria toxin linked by disulfide bond was gained by protease hydrolysis.

为建立重组基因表达白喉毒素的分离纯化方法，制备出具有生物活性的蛋白质毒素，构建了白喉毒素表达载体pET22b-DT，并转入大肠杆菌BL21(DE3)中诱导表达，以融合表达的His-6作为标签通过亲和层析纯化；表达毒素经蛋白酶酶切后，形成了以二硫键连接的与天然结构相同的带"缺口"的白喉毒素，并测定白喉毒素对豚鼠的急性毒性和细胞毒性。

The book comprehensively reviews the molecular and cellular biology of the most important microbial toxins with a focus on recent advances in the field, covering topics such as toxin ADP-ribosylation of proteins, toxin inhibition of protein synthesis, modulation of actin cytoskeleton, cytolethal distending toxins, cell-damaging/pore-forming toxins, clostridial neurotoxins, toxins of the immune system, streptococcal and staphylococcal toxins, anthrax toxins, Shiga toxin, Yersinia toxin, mycotoxins, and the regulation of toxin expression, as well as the potential of microbial toxins in bioterrorism.

该书全面评论了最重要的微生物毒素的分子与细胞生物学，重点是这一领域中的最新进展，主题包括蛋白质毒素ADP核糖基化，毒素抑制蛋白质合成，肌动蛋白细胞骨架的调控，细胞致死增加毒素，细胞损伤/孔状毒素，梭菌属的神经毒素，免疫系统的毒素，链球菌和葡萄球菌毒素，炭疽毒素，Shiga毒素，Yersinia毒素，毒枝菌素，和毒素表达调节，以及生物恐怖中微生物毒素的潜在可能性。

The results showed:among the 7 isolates, five isolates of HY3、GY1－3、ZJ1－1、HP1、FC3 had same colony shape, irregular shape, liquidlike, slimy, opacity with smooth surface;the other two isolates had same shape, irregular shape, dry, opacity with coarse surface. By inoculating eucalyptus with the 7 isolates, the plants were infected apparently, and the young plants of eucalyptus in control experiment with tap water were not infected. By cultivating eucalyptus cuttings with the bacterial suspensions without EPS, the incidence of disease was very distinct,but compared with the former bacteria suspension,the incidence of disease has decreased at different degrees. By screening out two isolates of strong pathogenicity and two isolates of weak pathogenicity from the 7 isolates,making the bacterial suspensions with them to inoculate the young plants of eucalyptus, two treatments of cutlings and ramets with rats were set with 5 repetitions in every treatment, the results of data analysis showed: for the cutlings, the bacterial contents in upper and middle parts、upper and lower had significant difference;for ramets with roots, the bacterial contents in upper, middle parts, lower had significant difference between each other; For both the cutlings and ramets with roof, the bacterial contents in xylem and phloem had significant difference. The interaction between vertical and horizontal parts for the bacterial content had significant difference. For the two isolates of HY3 and 93B which were screened out at last,their activities of the cellulase were: 1.955ug/ and 1.288ug/ respectively, and had significant difference; the activities of pectase were: 1.325 ug/and 1.24ug/ respectively, and had no significant difference. The content of EPS extracted from the two isolates of HY3 and 93B was very different: 7.08x10-8ug/cell and 5.17x10-8ug/cell.

结果显示：7个菌株中，其中5个菌株HY3、GY1－3、ZJ1－1、HP1、FC3的菌落形态相同：不规则形状、流体、粘性、不透明、表面光滑；另外2个菌株93B、GN1菌落形态相同：不规则形状、干燥、不透明、表面粗糙；用7个菌株接种剪根桉树苗，发病情况非常明显，而自来水对照实验中桉树苗却不发病；无EPS菌悬液培养桉树剪根苗，发病率也很明显，但是相比原菌液，则发病率有不同程度的下降；从7个菌株中间筛选出来2个强致病性菌株和2个弱致病性菌株，用它们配制菌悬液培养桉树苗，设置剪根和不剪根两个处理，每个处理设置五个重复，数据分析结果显示：对于剪根苗，上部和中部、上部和下部的含菌量有显著的差异，中部和下部含菌量差异不显著；带根苗，上部、中部、下部含菌量彼此之间差异显著；不管是剪根苗还是带根苗，木质部和韧皮部含菌量之间的差异都非常显著；上中下与木韧交互作用中，含菌量差异非常显著；最后筛选出来的强弱2个菌株HY3和93B，它们的纤维素酶活性分别为：1.955ug/和1.288ug/，具有显著的差别；果胶酶的活性分别为：1.325 ug/和1.24ug/，没有显著的差别，而且HY3和93B两个菌株细胞分泌的胞外多糖的含量差异很显著，分别为：7.08×10-8ug/cell和5.17×10-8ug/cell。

For further understanding the effect of the strain on K-bearing silicate mineral, an experiment with KO2 strain cultured in nitrogen-containing and nitrogen-free medium was conducted. By putting mineral powders into the medium and measuring the concentration of capsular polysaccharides, we concluded that the strain can accelerate the weathering rate of silicate minerals. The results showed that the polysaccharides secreted by the strain in the growth process could help the bacterial to adhere to the mineral surface effectively, and created the bacterium-mineral complex, which formed a mircro-enviorment avail the release of potassium. Another result was that there was higher level of Carbonic Anhydrase activity, which revealed that some exo-protein or enzyme produced by the bacterial had postive impact on the process of releasing potassium ion. We carried out the bacterial fermentation for larger scale production of the bacterial secretion, which was used to sperate, and identify the small molecules related to the mineral-bacterial interaction. After the analysis, it was found that the strain can produce many kinds of small molecules, such as 2-Hydroxybenzoic acid, 4-Hydroxyphenylacetic acid, methyl-4-hydroxybenzoate, etc.

分别将菌株接入含有不同矿粉的培养基中培养，检测其在有氮、无氮培养基中荚膜多糖含量的变化，并在以钾长石和黑云母为矿源的情况下，比较研究了菌株在有氮、无氮培养基中对矿物的风化能力，通过一系列的实验，证实胶质芽孢杆菌在生长过程中所分泌的粘稠胞外聚糖可帮助细菌有效黏附在矿物表面，形成细菌-矿物复合体，并改变及维持该复合体内部的微环境，有助于该菌的解钾作用，而且细菌分泌的胞外蛋白质在该菌对含钾硅酸盐矿物的解钾作用过程中发挥重要作用；将胶质芽孢杆菌接入以钾长石和黑云母为矿源的有氮、无氮培养基中培养，检测到该菌碳酸酐酶活性的变化，并进行批量发酵后小分子酸性分泌产物的提取、分离、纯化与鉴定等方面的研究，结果表明，该菌可产生2-羟基苯甲酸，4-羟基苯乙酸，4-羟基苯甲酸甲酯等小分子物质。

PAL activity, chitinase activity, total Polyphenol content and total Flavonoids content in soybean leaves induced by the same crude toxin and race were similar, it stated that the crude toxin is an important factor which can induce resistant substances, but the induced speed and the induced intensity by the crude toxin and conidium were different. Firstly, the induced speed of crude toxin which induced PAL activity and total Flavonoids content of resistant soybean varieties was faster than speed of C.

同一生理小种的粗毒素与灰斑病菌对大豆叶片内PAL活性、总多酚类含量、总黄酮含量以及几丁质酶活性等几种生化指标均表现出相似的诱导作用，由此可推断粗毒素是诱导大豆叶片内的PAL活性、总多酚含量、总黄酮含量以及几丁质酶活性产生变化的主要生物因子，只是二者在对抗性不同的大豆品种的诱导速度及强度上存在一定的差异。

Purification and analysis of AT-toxin Firstly, we detected the components of protein and nonprotein, the results showed that AT-toxin is a nonprotein. We have carried out the liquid chromatogram analysis of the toxin. The result indicates that there are many components in this toxin and there are four kinds of components which content is more than others. At last, we have the experiment of separating the cpmpositions with the silica gel and we get four components which are active.

AT-毒素的初步纯化与分析为确定AT-毒素的组分，首先对毒素的蛋白质和非蛋白质组分的毒性进行了测定，结果表明：AT-毒素活性组分为非蛋白质；对毒素进行硅胶G薄层层析，初步分离得到10种组分，其中四种组分具有活性：组分Ⅵ、Ⅶ、Ⅷ、Ⅸ，初步说明了该毒素含有多种组分；进一步对该毒素进行液相色谱分析，也发现该毒素含多种组分，其中四种组分峰高和峰面积较大，含量较高；其致毒活性可能是由这些组分协同作用的结果，它们之间可能存在正协同或负协同作用关系。

In this dissertation, firstly, the conditions of isolation and purification of specific toxin fractions produced by Exserohilum turcicum has been studied, and a high-efficient method has been established;secondly, the toxins were analysed by UV-Vis spectrophotometry;then the effect of specific toxin on death rate of corn leaves protoplast was studied by FDA as a tinct reagent;finally, using ANS as a probe and SDS-PAGE to study the membrane protein of the corn leaves with Htl gene. In a word, the aim of the research is to search some existent evidences of the toxin binding site on protoplasmic membrane, and provide proofs for nosogenesis of specific toxin in terms of cytology and the molecular biology.

本研究对玉米大斑病菌1号小种毒素的特异性组分进行分离，建立了高效的特异性毒素分离纯化方法，并对其进行了紫外波谱分析；用荧光素双醋酸酯染色法，测定了毒素特异性组分对原生质体死亡率的影响；进而用1-苯胺基-8-萘磺酸荧光探针标记法和SDS-PAGE电泳法对特异性毒素组分与Htl基因玉米细胞互作过程中的质膜蛋白进行了研究，旨在证明Htl基因玉米细胞质膜上存在特异性毒素组分结合蛋白，为从细胞和分子生物学角度阐明毒素的致病机理提供证据。

The main reasons were that the algae and organism in the water decreased the ability of removing pollutants by coagulations, the algae which grown again in the open sedimentation tank weakened the removal effect of algae by coagulation; because of the accumulation of algae and algae toxin in the filtration tank, the concentration of algae toxin in the effluent increased; by the function of fluid chlorine, the algae and organisms after the filtration will release microalgae toxin and produce a lot of byproduct such as microalgae toxin, sobomyl and so on, meanwhile, the chlorination produce considerable halide and halo-acetic acid and other disinfection byproduct.

主要表现在藻类和溶解性有机物的存在降低了混凝去除污染物的能力；藻类在露天平流沉淀池中再生长，抵消了混凝除藻效果；藻类和藻毒素在滤池中积累，导致滤后藻毒素升高；穿透滤池的藻类和有机物在液氯作用下，释放微囊藻毒素、土臭素和二甲基异冰片等胞内物质，同时生成数量可观的卤代烃和卤乙酸等消毒副产物。

For example,1889-1890 years, the people studies the diphtheria toxin and the tetanus infection toxins with the immunology technique, using it again later on to study the plant toxin, such as the castor toxin, the croton toxin and snake poison, spider poison within the animal toxins.

例如，1889～1890年，人们用免疫学技术研究白喉毒素和破伤风毒素，随后又用它来研究植物毒素，如蓖麻毒素、巴豆毒素和动物毒素中的蛇毒、蜘蛛毒。

Material and method the 1.1 objects that monitor in January 2005 ~2007 year in December, nantong city disease accuses a center to monitor bar of hall of inn of the inn inside the area, communal bathroom, tonsorial hairdressing, song to wait public 771, every random and draw-out a certain number of the sample of public articles for use that the preparation after cleaning disinfection uses in all 4 960 portion. Crock of pool of the tea service of the 1.2 content that monitor and methodological inn, towel, bed sheet, face, bath, chamber pot undertakes group testing of bacterial gross, coliform measures; the towel of communal bathroom, bathrobe undertakes group testing of bacterial gross, coliform measure, slipper undertakes mould and microzyme detect the tea service of; public place of entertainment undertakes group testing of bacterial gross, coliform measures; the towel of tonsorial hairdressing place, scissors undertakes bacterial gross, coliform group detect with coccus of golden yellow grape.

梗概： 为了解南通市近几年公共场所卫生状况，客观评价公共场所卫生水平，为今后的卫生监督监测提供科学依据，对2005年~2007年南通市公共场所公共用品(茶杯、口杯、床上用品等)的细菌总数、大肠菌群等微生物检测进行了分析，结果报告如下。1材料和方法1.1监测对象2005年1月~2007年12月，南通市疾控中心监测区内的旅店、公共浴室、理发美容店、歌厅酒吧等公共场所771家，每家随机抽取若干件清洗消毒后预备使用的公共用品样品共4 960份。1.2监测内容和方法旅店的茶具、毛巾、被单、面池、浴缸、便桶进行细菌总数、大肠菌群检测；公共浴室的毛巾、浴衣进行细菌总数、大肠菌群检测，拖鞋进行霉菌和酵母菌检测；娱乐场所的茶具进行细菌总数、大肠菌群检测；理发美容场所的毛巾、剪刀进行细菌总数、大肠菌群和金黄色葡萄球菌检测。

More direct, directer ; most direct, directest

径直的，笔直的

Do you know how to use a chain saw?

你知道如何使用链锯吗？