Bacterial_Transformation
微生物英文名词解释
微生物英文名词解释1.Mycoplasma：The mycoplasma are a group of the smallest organisms withoutcell wall that can be free-living in nature, can pass through bacterial filter and also grow on laboratory media.2.Chlamydia：Chlamydia are small Gram-negative bacteria which are obligateintercellular parasites like virus, but differ from them in that they have both RNA and DNA, ribosome, cell wall, and divided by binary fission.3.L forms of bacteria：In osmotically protective media, removal of the bacterialwall with lysozyme or penicillin liberate protoplasts from Gram-positive cells and spheroplasts from Gram-negative cells. If such wall-defective cells are able to grow and divide, they are called L forms. L forms are difficult to cultivate. They require a special media. Some L form can revert tothe normal bacillary form. L form in the host may produce chronic infection that are relatively resistant to antibiotic treatment.4.Capsule：Many bacteria synthesize large amounts of extracellular polymer whengrowing in their natural environments. When the polymer forms a condensed, well-defined layer closely surrounding the cell, it is called the capsule. With one known exception (the polypeptide capsule), the polymer is polysaccharide.5.Pyrogen：This is a fever-producing substance synthesized by bacteria. In fact, itis the lipopolysaccharide of Gram-negative bacteria. For the injectable medicament, it is especially important to avoid the contamination of pyrogen in the course of pharmic production.6.Exotoxin：Exotoxins are proteins produced inside Gram-positive bacteria cellsand secreted into the environment. These toxins are some of the strongest poisons known to man and cause violent reactions in host organisms.7.Endotoxin：Endotoxins are made up of lipids and carbohydrates associated withthe outer membrane of gram-negative bacteria. These toxins usually produce fever, weakness, and capillary damage.8.Disinfection: Reduce or eliminate pathogens病原体in or on inanimate无生命的objects to a safe level, which are no longer health hazard危险.9.Sterilization: A physical or chemical process that completely destroys orremoves all microbial life，including bacteria spore and viruses.10.Antisepsis: Use chemical agents to inhibit or destroy the growth ofmicroorganisms on skin or other living tissue.11.Plasmids：Plasmids are small genetic elements that replicate independently of thebacterial chromosome. Most plasmids are circular, double-stranded DNA molecules varying from 1,500 to 400,000 base pairs. Like the bacterial chromosomal DNA, they can autonomously replicate and as such are referred to as replicons.12.Transformation：It is the process by which bacteria take up fragments of nakedDNA and incorporate them into their genomes. During transformation, DNAfragments from a dead degraded bacterium bind to DNA binding proteins on the surface of a competent recipient bacterium.13.Conjugation：Conjugation is the transfer of DNA directly from a living donorbacterium to a recipient bacterium during the mating of the bacteria. A sex pilus produced by the donor bacterium (or male) binds to the recipient (or female). The sex pilus then retracts, bringing the two bacteria in contact and the transferred DNA passes through the sex pilus.14.Transduction：Transduction is mediated by a bacteriophage, which pick upfragments of DNA and package them into bacteriophage particles. The DNA is delivered to infected cells and becomes incorporated into the bacterial genomes.15.Normal flora:The various bacteria and fungi that are permanent residents ofcertain body sites, especially the skin, oropharynx, colon, and vagina.16.Dysbacteriosis：If flora disequilibrium occurs, for example, when the residentflora is disturbed, some little significant microorganisms may colonize, proliferate and produce diseases, which are called dysbacteriosis. Dysbacteriosis mainly result from long term and large bacteriosis mainly result from long term and large bacteriosis mainly result from long term and large doses antibiotics taken. Antibiotics can suppress the drug-susceptible components of fecal flora.Soon thereafter the counts of fecal flora rise again to normal or higher than normal levels, principally of organisms selected out because of relative resistance to the drugs employed. The drug susceptible microorganisms are replaced by drug-resistant ones and cause correlative disease, microbial selection and substitution.17.Toxemia：Bacteria multiply at invading location and do not enter blood stream,but the exotoxins enter blood and cause corresponding toxic symptoms.18.Endotoxemia：Gram-negative bacteria multiply at location or in blood stream,release a lot of amount endotoxin released from bacterial cell rupture.19.Protein A ：Protein A is a cell wall component of many S. aureus strains thatbinds to the Fc portion of IgG molecules except IgG3. The Fab portion of IgG bound to protein A is free to combine with a specific antigen. Protein A has become an important reagent in immunology and diagnostic laboratory technology; for example, protein A with attached IgG molecules directed againsta specific bacterial antigen will agglutinate bacteria that have that antigen(“coagglutination”). Protein A probably contributes to the virulence of S. aureus by interfering with opsonization.20.Elementary body（EB）：Elementary body（EB）are small round cells about0.2～0.4μm with an electron-dense nucleoid. They possess a cell wall. They areextracellular form and the environmentally stable infectious particle ，and metabolically inactive. The EB have a high affinity for host epithelial cells and rapidly enter them，creating a protected membrane-bound environment around the chlamydiae，and the Elementary body is reorganized into a larger one called metabolically active Reticulate body（RB）.21.Reticulate body（RB）：The intracellular large form known as the reticulate bodyMeasuring about 0.5～1μm and devoid of an electron-dense nucleoid. Itspresence will reflect the stage of replication. Within the membrane-bound vacuole，the elementary grows in size and divides into repeatedly by binary fission. Eventually，the entire vacuole becomes filled with elementary bodies derived from reticulate bodies to form a cytoplasmic inclusion. The newly formed elementary bodies may be liberated from the host cell to infect new cells. The developmental cycle takes 24-48 hours.22.nucleocapsid：The simplest of virus particles consists of a protein coat (capsid)which surrounds a strand of nucleic acid and are thus called naked viruses or nucleocapsid.23.Abortive Infections：Not all infections lead to new progeny virus. Productiveinfections occur in permissive cells and result in the production of infectious virus. Abortive infections fail to produce infectious progeny, either because the cell may be nonpermissive and unable to support the expression of all viral genes or because the infecting virus may be defective, lacking some functional viral gene.24.defective virus：A defective virus is one that lacks one or more functional genesrequired for viral replication. Defective viruses require helper activity from another virus for some step in replication or maturation. One type of defective virus lacks a portion of its genome (i.e., deletion mutant). The extent of loss by deletion may vary from a short base sequence to a large amount of the genome.Deletion mutants may arise spontaneously or may be constructed in the laboratory using biochemical techniques.25.Interferons (IFN s)：Interferons (IFN s)are proteins made and released by hostcells in response to the presence of pathogens such as viruses, bacteria, parasites or tumor cells. They allow for communication between cells to trigger the protective defences of the immune system that eradicate pathogens or tumors. 26.Antigenic drift: Antigenic drift is constantly occurring in both influenza A andinfluenza B viruses. The HA and/or NA of the new strain are sufficiently different to evade (at least partially) the pre-existing human immunity. This leads to the seasonal epidemics.27.Antigenic shift:Antigenic shift occurs only in influenza A virus. It describes theemergence of an entirely new virus sub type. When this new sub type emerges, it causes a pandemic because there is no pre-existing immunity in humans.。
实验 14以质体DNA对大肠杆菌进转型作用(Transformation)
實驗 14以質體DNA 對大腸桿菌進行轉型作用(Transformation)概述很多分子生物策略之所以成功，是與能有效地取得感興趣之DNA載體有關。
進行細菌轉型作用最常用的一種方法是加入大量的calcium chloride，導致大腸桿菌的細胞壁發生結構上的變化，而有利於質體DNA(載體)進入細菌細胞內。
另一種較迅速的方法是在LB培養液中加入冰的10%(w/v)PEG,5%(w/v) dimethyl sulfoxide(DMSO)，及50mM magnesium chloride，只須一個步驟就可以製備出勝任細胞(Compentent cell)，之後可以保存直至有需要時再拿出來用(Chung et al,1989)。
一般來說，將質體DNA引入細胞中有三個主要步驟:(1)勝任細胞之製備；(2)使勝任細胞轉型;(3)篩選轉型細胞。
大部份大腸桿菌品系的轉型效率在105-108之間(即每ug質體中轉型細胞之數目)。
影響此效率之因子與勝任細胞狀況或吸收DNA之能力有關。
而這兩項因子又愛○1是否用對數生長期之細胞○2處理時是否將細胞保持在4°C下○3曝露於冰的calcium chloride的時間等所影響。
勝任細胞製備完成後，利用熱休克處理，使細胞外梢的油脂變性而刺激轉型作用。
爾後給予一段時間恢復後，可用對抗生素之抗性標記，進行篩選工作。
不同的細胞品系和載體之理想轉型作用效率，有不同的係數和條件。
有些因子如質體的大小，DNA的異構現象(緊密的，直線狀的，或有缺口的)及抗生素標記的篩選等，都會影響轉型作用之實驗結果。
試劑/工具名稱規格數量一瓶氯化鈣(Calcium ChlorideSolution)離心管10-15ml 數支大腸桿菌LE 392 一瓶LB平板(LB培養液加20g洋菜/L)一瓶含氨卡青黴素(ampicillin)的平板一瓶LB培養液一瓶一瓶含氨卡青黴素(ampicillin)的LB培養基pRY121 DNA 一瓶TE緩衝液一瓶試管13x100mm 數支氯化鈣離心管大腸桿菌LE 392 LB平板含氨卡青黴素的平板LB培養液含氨卡青黴素的LB培養基 pRY121 DNATE緩衝液試管儀器/設備名稱規格數量4°C離心機一台37°C培養箱一台分光光度計一台37°C恆溫振盪器一台45°C水浴一台4°C離心機37°C培養箱分光光度計37°C恆溫振盪器45°C水浴導師注意事項1﹒以無菌方法將大腸桿菌LE 392移到含5ml LB液體培養基的試管中，並在37°C下振盪培養一個晚上。
电感受态细胞制备
根据诸多文献，提出如下红球菌电转化感受态细胞制备方案：1.接种一环红平红球菌/紫红红球菌到LB培养基里，30°C，170转/min 过夜培养。
2.取1.0-1.5ml过夜培养菌液，4000转/min离心3min,无菌水洗涤，重新离心一次，重悬浮于1.0ml无菌水中。
3.转移100uL上述菌悬液到一个装有100mlMB培养基的培养瓶中(MB medium (5 g/l酵母膏, 15 g/l胰蛋白胨,5 g/l大豆蛋白胨, 5 g/l NaCl, 2.0%甘氨酸, 1.8%蔗糖，pH7.2。
灭菌后加入0.25ug/m L青霉素G)试验最佳生长培养基：LB含0.5M蔗糖；LB含0.5M山梨醇；LB含0.5M甘露醇；LB+0.5M 蔗糖+0.5M山梨醇；LB+0.5M蔗糖+0.5M甘露醇；LB+0.5M山梨醇 +0.5M甘露醇；MB培养基4. 30°C，170转/min 振荡培养过夜或者O.D.600值达到0.8-1.0之间。
5.用灭菌的离心管（10ml）或者50 ml锥形管和适当的适配器在GSA转子里以 4 000 rpm 的速度离心10分钟（如果细胞没有沉淀下来，改变离心时间和转速为4000g/min，10min）6. 倒掉上清，加入6mL预冷的蒸馏灭菌水，轻轻洗涤，4 000 rpm的速度离心10分钟。
7. 倒掉上清，再次将细胞沉淀加入到6mL预冷的5%甘油蒸馏灭菌，水轻轻洗涤，4 000 rpm 的速度离心10分钟。
8. 用6ml的10%灭菌的冰冻甘油洗涤细胞沉淀一次，4000 rpm的速度离心10分钟。
（重复一次）9. 用6ml的10%灭菌的冰冻甘油洗涤细胞沉淀一次，4000 rpm的速度离心10分钟。
10. 用5ml（20倍浓缩）或更少（40倍浓缩）的灭菌冰冻甘油对细胞沉淀进行重悬浮11. 按120μl等份装入灭菌的微型离心管中于-80°C储藏电转化：1.取400uL冷冻红球菌感受态细胞2.加入1uL质粒DNA(0.5ug),轻轻混匀，冰上放置30min(500ng/400ul=125ng/ul)3.将上述感受态细胞—质粒DNA混合物转移到预冷的0.2cm的电击杯内4.设置电击参数为：电压2.5kV,电抗400Ω，电容25.0uF,脉冲7.0ms5.电转后立即加入1mLLB培养基，30℃培养3h6.适当稀释后涂布LB培养基。
接合、转化、转染、转导的区别
接合、转化、转染、转导的区别转化，转导，转染的区别是什么--------------------------------------------------------------------------------转化(transformation)指将质粒或其他外源DNA导入处于感受态的宿主细胞，并使其获得新的表型的过程。
转染（transfection）采用与质粒DNA转化受体细胞相似的方法，即宿主菌先经过CaCl2，电穿孔等处理成感受态细菌，再将重组噬菌体DNA直接导入受体细胞，进入感受态细菌的噬菌体DNA可以同样复制和繁殖，这种方式称为转染。
转染是转化的一种特殊形式。
转导Transduction 是指通过病毒将一个宿主的DNA转移到另一个宿主的细胞中而引起的基因重组现象。
如果供体DNA未与受体DNA发生重组则称此转导过程为流产转导.1、Conjugation 中文翻译为“结合”Conjugation is the mechanism by which genetic material is transferred between two bacterial cells by plasmids. A cell containing a conjugativeplasmid(F+,fertility+)forms a mating pair with a cell that does not contain a conjugative-plasmid(F-)by means of an F-pilus on the surface of the cell.The pilus contracts,pulling the two cells into contact, and the conjugative plasmids(typified by the F plasmid of E.coli ) is transferred from the plasmid-containing cell, the donor, to the recipient(in some cases,pieces of chromosomal DNA is also transfered to the recipient). The tra genes, carried on the F plasmid, contain all the information for the conjugative process.《Instant notes in Microbiology》p125说明：Conjugation 发生在原核生物，这个定义里面的关键是“ The pilus contracts,pulling the two cells into contact”这种细胞间的直接接触。
3细菌的遗传和变异
病原生物学Pathogen Biology第三章细菌的遗传和变异概述•遗传（heredity）是指生物子代与亲代之间的性状相同性；•变异（variation）则是指生物子代与亲代之间性状的差异性。
–遗传性变异(基因型变异),是不可逆的，产生的新性状可稳定的遗传给子代–非遗传性变异(表型变异),不能遗传。
•遗传使细菌的种属性状相对稳定,变异可使细菌产生变种和新种。
一、细菌的遗传物质(Genetic materials of bacteria)1.染色体(chromosome)2.质粒(plasmid)3.前噬菌体(prophage)4.转座子(transposon, Tn)真核和原核生物染色体的区别*霍乱弧菌有两条染色体，大的含2961146bp，小的含1072314bp*细菌rRNA编码基因是多拷贝以装备大量核糖体满足细菌生长需求真核和原核生物染色体的区别操纵子（operon）：指包含结构基因、操纵基因以及启动基因等相邻基因组成的DNA片段，其中结构基因的表达受到操纵基因的调控。
主要见于原核生物，其大多数基因表达调控是通过操纵子机制实现的。
第二节细菌遗传变异的物质基础基因组：染色体和染色体外遗传物质质粒转位因子一条环状双螺旋DNA长链,反复卷曲缠绕形成松散的网状结构,外无核膜包裹,仅附着在横隔中介体上或细胞膜上.1. 细菌的染色体(Bacterial chromosome)1.1 多种形式•一条环状双链DNA：大多数（>90%）细菌，大小范围在580kbp～5220kbp之间•两条环状dsDNA：少数细菌（如霍乱弧菌，问号钩端螺旋体，马耳他布鲁菌）•三条环状dsDNA：paracoccusdernitrificans•线性dsDNA：疏螺旋体属（Borrella）伯氏疏螺旋体、迦氏疏螺旋体、埃氏疏螺旋体和radyrhizobiunjaponicum 等1. 细菌的染色体(Bacterial chromosome)1.2 染色体上有耐药基因(drug resistance gene)和致病岛(pathogenicity island)的存在，细菌种内和种间可交换pathogenic island：指菌基因组中编码与细菌毒力相关因子的外源DNA（1～200kb），两侧有重复序列、插入序列或tRNA。
鱼类生殖细胞移植的研究进展及应用前景
在鱼类胚胎发育早期，体细胞系和生殖细 胞系就发生了分离，形成了生殖细胞的祖细 胞，即PGCs。随后，PGCs迁移到达生殖原基， 增殖、分化为精原细胞或卵原细胞，接着开始 配子发生。在精巢中，精原细胞发育为精子需 要经过3个阶段：有丝分裂(精原细胞增殖)、减 数分裂(初级和次级精母细胞形成)、精子生成[36-37]。 在有丝分裂阶段，具有干细胞特性的未分化A型 精原细胞(Aund)通过有丝分裂产生分化的A型精 原细胞(Adiff)，同时伴随着自我更新能力的大幅 降低，然后Adiff继续分裂产生B型精原细胞；通 常把Aund称为精原干细胞[36, 。 38-39] 卵巢中，卵原 细胞经过有丝分裂增殖后，快速进入到减数分 裂阶段，成为初级卵母细胞，经过初级、次级 生长及卵黄生成后，发育成为卵子。在卵原细 胞增殖过程中，部分卵原细胞保持干细胞特
水产学报, 2020, 44(2): 321−337
JOURNAL OF FISHERIES OF CHINA DOI: 10.11964/jfc.20190511781
·综述·
鱼类生殖细胞移植的研究进展及应用前景
叶 欢1， 危起伟1， 徐冬冬2， 岳华梅1， 竹内裕3， 阮 瑞1， 杜 浩1， 李创举1*
鱼类生殖细胞移植技术首先在斑马鱼daniorerio中建立10经过十多年的发展该技术取得了一系列突破性的进展包括先后建立了以胚胎仔鱼和成鱼为受体的生殖细胞移植模式41011供体生殖细胞的选择从pgcs拓展到精原和卵原干细胞46受体的选择与制备等1215
文章编号: 1000-0615(2020)02-0321-17
2 鱼类生殖细胞移植
鱼类生殖细胞移植主要包括供体细胞、受 体的选择与制备，以及二者的亲缘关系等关键 科学与技术问题。
全基因组CRISPRCas9高通量筛选人体细胞中的功能基因组学
全基因组CRISPRCas9高通量筛选人体细胞中的功能基因组学点击左上方蓝字“HACS”！全基因组CRISPR/Cas9高通量筛选人体细胞中的功能基因组学英文名：《Genome-Wide CRISPR/Cas9 Screening for High-Throughput Functional Genomics in Human Cells》简单说就是利用CRISPR/Cas9技术对人类的基因组（23对染色体上的全部基因，大约两万个）进行筛查，看看这些基因到底有哪些功能。
摘要基因作为生命的本质，基因的具体功能一直是科学家的研究方向。
我们知道人体的基因组大约有两万个基因，研究一个基因的工作量就已经很大，这意味我们不可能一个一个地研究每一个基因。
如果能以高通量的方式鉴定基因的功能，那么我们就可能进行全基因组基因功能研究，而近几年来的CRISPR/Cas9系统已经可以满足这样的需求，这也是目前研究的热点。
在这里，我们介绍一种可以产生覆盖全人类基因组的慢病毒单链引导RNA (sgRNA)文库的通用方法。
CRISPR/Cas9系统有两个重要组成部分，包括Cas9蛋白并sgRNA，前者可以切割DNA，相当于一个士兵；后者起到引导作用，将CRISPR/Cas9这个编辑器引导到靶位点，相当于指挥官；sgRNA可以覆盖全基因组就意味着CRISPR/Cas9这个编辑器可以对全基因组进行编辑。
因为可以覆盖全基因组，而且具有普适性，这个实验方法将成为各种模式动物，各种生物活动相关基因研究的有力工具。
关键词 CRISPR-Cas9系统，高通量，敲除，筛选，sgRNA。
一. 背景介绍CRISPR/Cas9系统是古菌和细菌常用的一种防御系统[1]。
不过这并不重要，毕竟英雄不问出处。
目前，应用最最广泛的工程设计CRISPR/Cas体系由Cas9核酸酶和单链引导RNA (sgRNA)组成。
引导 RNA (sgRNA) 是一段长度为20bp的核糖核酸序列。
遗传学名词解释
遗传学名词解释●law of segregation（分离定律）：一个遗传性状的两个等位基因在配子形成过程中是分离的，最终形成不同的配子●law of independent assortment（自由组合定律）：应当具有两对（或更多对）相对性状的亲本进行杂交，在子一代产生配子时，在等位基因分离的同时，非同源染色体上的非等位基因表现为自由组合。
●The Law of Dominance（显性定律）：在杂合子中，一个等位基因可以隐藏另一个等位基因的存在。
●allele（等位基因）：是指位于一对同源染色体相同位置上控制同一性状不同形态的基因。
●test cross（测交）：是一种特殊形式的杂交，是杂交子一代个体(F1)再与其隐性或双隐性亲本的交配，是用以测验子一代个体基因型的一种回交。
●monohybrid（单因子杂种）：指只有1对等位基因不同的两个（同质的）亲本所形成的杂种。
●dihybrid（双基因杂种）：二对等位基因不同的两亲间的杂种。
●Complete dominance（完全显性）：发生在杂合子和显性纯合子表型相同的情况下。
●incomplete dominance（不完全显性）：f1杂种的表型介于两个亲本的表型之间。
●codominance（共显性）：两个显性等位基因以不同的方式影响表型。
●multiple allele（复等位基因）：一个基因有两个以上的等位基因。
●allele frequency（等位基因频率）：基因的每个等位基因占基因拷贝总数的一个百分比，这个百分比称为等位基因频率。
●monomorphic genes（单型的基因）：这种基因只有一种常见的野生型等位基因。
●polymorphic genes（多态性基因）：有些基因有一个以上的等位基因。
●Pleiotropy（多效性）：一个基因可能导致几个特征。
●Recessive epistasis（隐性上位）隐性等位基因需要隐藏另一个基因的作用，这种掩蔽现象称为隐性上位。
非等位基因
非等位基因概述非等位基因是指同一基因座上的不同等位基因。
等位基因是指在某个给定的基因座上，可以存在多种不同的变体。
每个个体继承了一对等位基因，一对等位基因可能会导致不同的表型表达。
非等位基因的存在使得遗传学研究更加复杂，因为不同的等位基因会对个体的表型产生不同的影响。
背景在生物学中，基因座是指染色体上一个特定的位置，该位置上的基因决定了某个特征的表达方式。
每个基因座上可以有多种不同的等位基因。
等位基因是指在某个特定基因座上的不同基因变体。
每个个体都会继承一对等位基因，通过这对等位基因的不同组合，决定了个体的表型。
然而，并非所有基因座上的等位基因都具有相同的表现型。
非等位基因的影响非等位基因的存在导致不同等位基因会对个体表型产生不同的影响。
有些非等位基因会表现出显性效应，也就是说，当个体继承了一个突变的等位基因时，即使同时继承了一个正常的等位基因，但显性效应会使得突变的等位基因的表型表达得到体现。
相反，有些非等位基因会表现出隐性效应，当个体继承了两个突变的等位基因时，才会表现出突变的表型。
除了显性和隐性效应之外，非等位基因还可能发生两种其他类型的表型效应。
一种是共显效应，当个体继承了两个不同的突变等位基因时，在表型表达上会表现出一种新的特征，这个特征并不是单个突变等位基因所能导致的。
另一种是部分显性效应，当个体继承了两个不同的突变等位基因时，表型表达将介于两个单独突变等位基因的表型之间。
重组和非等位基因重组是指两个不同的染色体交换部分基因序列的过程。
在重组的过程中，非等位基因可能会发生改变，导致新的等位基因组合形成。
这一过程使得非等位基因的表型效应更加复杂，因为新的等位基因可能将不同基因座的效应组合起来。
非等位基因的重要性非等位基因对生物的适应性和多样性起着重要作用。
通过对等位基因的各种组合的研究，人们可以更好地理解基因与表型之间的关系，并揭示遗传变异对物种适应环境的重要性。
总结非等位基因是指同一基因座上的不同等位基因。
突变基因与呼吸系统疾病的联系
突变基因与呼吸系统疾病的联系突变基因是指在个体遗传物质DNA序列中发生突变，导致基因功能的改变。
这些突变可能与许多疾病的发生和发展有着密切的联系，尤其是与呼吸系统疾病相关的基因突变。
本文将探讨突变基因与呼吸系统疾病之间的关联。
1. 突变基因与哮喘哮喘是一种慢性炎症性呼吸系统疾病，其特征是支气管高反应性、气道炎症和气流受限。
研究表明，多个基因突变与哮喘的遗传易感性密切相关。
例如，人类第5号染色体上的Cys-Leu突变与阻塞性空气道疾病（包括哮喘）的发生有关。
此外，Toll样受体4基因（TLR4）的D299G和T399I突变与哮喘的风险增加相关。
2. 突变基因与慢性阻塞性肺疾病（COPD）慢性阻塞性肺疾病是一种气道慢性炎症反应导致的进行性气流受限性呼吸系统疾病。
研究发现，一些突变基因与COPD的发生和发展相关。
例如，人类第6号染色体上的α1-抗胰蛋白酶（α1-antitrypsin）基因的突变导致该蛋白的缺乏，增加了COPD的风险。
3. 突变基因与肺癌肺癌是最常见的恶性肿瘤之一，并且与吸烟、环境污染等因素密切相关。
然而，研究表明，某些突变基因也与肺癌的发生有关。
例如，表皮生长因子受体（EGFR）基因突变可以导致癌细胞的无限增殖和肿瘤的发展。
此外，KRAS和TP53等基因的突变也与肺癌发生有关。
4. 突变基因与囊性纤维化囊性纤维化是一种影响多个器官的遗传性疾病，最常见的受累部位是肺部。
该疾病是由囊性纤维化转膜调节子（CFTR）基因的突变导致的。
不同的突变会导致CFTR蛋白的结构和功能发生改变，从而引起黏液的增加和器官功能损害。
总结起来，突变基因与呼吸系统疾病之间存在着紧密的联系。
这些基因突变可能会影响呼吸系统的发育和功能，导致呼吸系统的疾病发生和发展。
深入研究突变基因与呼吸系统疾病之间的关联有助于我们更好地理解这些疾病的发病机制，并为相关疾病的预防和治疗提供新的思路和方法。
参考文献：1. Marinho S, Simpson A. Cracking the case of childhood wheeze: could genetics hold the key? Archives of disease in childhood. 2019;104(2):195-196.2. Zhou H, Zhang L, Chen D, et al. Toll-like receptor 4 D299G andT399I polymorphisms are associated with increased risk of asthma: An updated meta-analysis. Medicine. 2020;99(14):e19677.3. Müller T, Müller G, Steinbach L, Fehrenbach H, Fühner T. Decoding the role of α1-antitrypsin deficiency in chronic obstructive pulmonary disease. Annals of the American Thoracic Society. 2016;13 Suppl 4:S317-s325.4. Shi J, Hua X, Zhu B, Ravichandran S, Wang M, Nguyen C. Lung cancer epidemiology, risk factors, and prevention. J Thorac Dis.2016;8(9):E981-e989.5. Alton EW, Stern M, Farley R, et al. Cystic fibrosis gene therapy: a new era in treatment for the UK CF gene therapy consortium. human gene therapy. 2013;24(5):440-452.。
质粒转化流程
质粒转化流程Transforming plasmids, also known as plasmid transformation, is the process by which foreign DNA is introduced into a bacterial cell. This process is essential in genetic engineering and molecular biology research, allowing scientists to manipulate the genetic makeup of bacterial cells for various purposes.质粒转化，也称为质粒转化，是外源DNA被引入细菌细胞的过程。
这个过程在基因工程和分子生物学研究中是至关重要的，它使科学家能够操纵细菌细胞的遗传结构，用于各种目的。
The first step in plasmid transformation is the preparation of competent bacterial cells. Competent cells are capable of taking up DNA from their environment, and preparing them involves treating them with various chemicals to increase their permeability to DNA.质粒转化的第一步是准备具有自主吸收DNA能力的细菌细胞。
将它们进行处理，使细胞对DNA的通透性增加。
The next step in the process is the addition of the plasmid DNA to the bacterial cells. This can be achieved through a variety of methods, including heat shock, electroporation, or chemical transformation. Each method has its pros and cons, and the choice of method depends on the specific needs of the experiment.接下来的步骤是将质粒DNA加入细菌细胞。
伯氏疏螺旋体 英文
伯氏疏螺旋体英文Title: Borrelia burgdorferi: An Insight into the Lyme Disease PathogenBorrelia burgdorferi, also known as Lyme disease spirochete, is a bacterial species belonging to the genus Borrelia within the spirochete family. It is a Gram-negative, microaerophilic organism that possesses a unique helical shape, characterized by 3 to 10 sparse spirals under microscopic examination. These spirochetes arefurther distinguished by their flagella, visible under electron microscopy, with 7 to 15 flagella at each end.The significance of Borrelia burgdorferi lies in its role as the causative agent of Lyme disease, a tick-borne infection that affects humans and other animals. Lyme disease is a multisystemic illness that can manifest with a range of symptoms, including skin rashes, arthritic pain, neurological problems, and cardiac abnormalities. The spirochete is transmitted to humans through the bite of infected ticks, primarily the Ixodes species.The lifecycle of Borrelia burgdorferi is intricately linked to its arthropod hosts. It spends part of its lifecycle within the tick, undergoing multiple stages of development before being transmitted to a new host. Once inside the host, the spirochete can disseminate throughout the body, invading various tissues and organs.The pathogenesis of Lyme disease involves complex interactions between Borrelia burgdorferi and the host's immune system. The spirochete possesses various virulence factors that enable it to evade immune clearance andpersist within the host. These factors include adhesinsthat facilitate attachment to host cells, proteases that degrade host proteins, and antigenic variation that allows the spirochete to evade immune recognition.The diagnosis of Lyme disease can be challenging due to the variable presentation of symptoms and the absence of a single, reliable diagnostic test. However, a combination of clinical symptoms, serological testing, and, in some cases, molecular detection methods can aid in the diagnosis. Treatment typically involves the administration ofantibiotics, which can effectively eliminate the spirochete in the early stages of infection.The ecology and epidemiology of Borrelia burgdorferi are also fascinating aspects of its biology. The spirochete is endemic in certain geographical regions, particularly those with high tick populations. Climate change and other environmental factors have been implicated in the expansion of tick habitats and, consequently, the increasing incidence of Lyme disease.Moreover, Borrelia burgdorferi exhibits genetic diversity, with multiple strains and subspecies identified. This diversity contributes to the variable clinical manifestations of Lyme disease and poses challenges for vaccine development and therapeutic strategies.Research into Borrelia burgdorferi and Lyme disease continues to evolve, with scientists seeking to better understand the spirochete's biology, pathogenesis, andhost-parasite interactions. This knowledge is crucial for developing more effective diagnostic tools, treatment options, and, ultimately, prevention strategies againstthis debilitating disease.In conclusion, Borrelia burgdorferi, the causativeagent of Lyme disease, is a complex and fascinatingorganism that holds significant implications for public health. Its unique biology and ability to evade immune clearance make it a challenging pathogen to combat. However, through continued research and innovation, we may one day find the key to preventing and effectively treating this debilitating disease.。
医学微生物经典问答题
（1）细菌生长可分为四个时期：迟缓期、对数期、稳定期、衰亡期。
各期特点：a.迟缓期：细菌进入新环境后的适应阶段，为大量繁殖作准备；对数期：生长迅速；形态、染色性、生理活性典型,因此, 采用此期观察细菌的性状(形态染色、生化反应、药物敏感试验等)；稳定期:由于营养物质消耗,有害代谢产物积聚,pH下降以及需氧菌菌数过密通气不良所致。
细菌的芽胞和外毒素、抗生素等代谢产物在此期产生；衰亡期:形态多样不典型（2）根据DNA片段的来源及交换方式不同，将转移与重组的方式分为：转化、接合、转导、溶原性转换和原生质体融合等。
转化(transformation)：是供体菌裂解游离的DNA片段被受体菌直接摄取，供受体菌获得新的性状。
接合（conjugation）：是细菌通过性菌毛相互连接沟通，将遗传物质（主要是质粒DNA）从供菌转移给受菌。
转导（transduction）：是以噬菌体为载体，将供菌的遗传物质转移到受菌中去，使受菌获得新的性状。
溶原性转换（lysogenic conversion）：是侵入细菌的噬菌体在溶原期可以前噬菌体形式在细菌内与细菌的染色体发生重组，导致细菌的基因型发生改变。
溶原性细菌可因此而获得新的性状（如白喉毒素、致热外毒素、肉毒毒素和α毒素）。
（3）一、细菌耐药性的概念细菌耐药性（drug resistance）亦称抗药性，是指细菌对某抗菌药物（抗生素或消毒剂）的相对抵抗性。
指病原体或肿瘤细胞对反复应用的化学治疗药物敏感性降低或消失的现象。
耐药性的程度用某药物对细菌的最小抑菌浓度（MIC）表示。
临床上有效药物治疗剂量在血清中浓度大于最小抑菌浓度称为敏感，反之称为耐药。
二、细菌耐药性的遗传机制遗传学上把细菌耐药性分为固有耐药性和获得耐药性。
(一)固有耐药（intrinsic resistance）固有耐药性指细菌对某些抗菌药物的天然不敏感。
固有耐药性细菌称为天然耐药性细菌，其耐药基因来自亲代，由细菌染色体基因决定而代代相传的耐药性，存在于其染色体上，具有种属特异性。
各种培养基
Bacterial E.coli Growth MediaCommonly used bacterial E.coli growth mediaLB (Luria Bertani) Miller broth (1%NaCl): 1% peptone, 0.5% yeast extract, and1% NaClLB (Luria Bertani) Lennox Broth (0.5% NaCl): 1% peptone, 0.5% yeast extract,and 0.5% NaClSOB medium (Super Optimal Broth): 2% peptone, 0.5% Yeast extract, 10mMNaCl, 2.5mM KCl, 10mM MgCl2 , 10mM MgSO4SOC medium (Super Optimal broth with Catabolic repressor): SOB + 20mMglucose2x YT broth (2x Yeast extract and Tryptone): 1.6% peptone, 1% yeast extract, and0.5% NaClHPO4,TB (Terrific Broth) medium: 1.2% peptone, 2.4% yeast extract, 72 mM K17 mM KH2PO4 and 0.4% glycerolSB (Super Broth) medium: 3.2% peptone, 2% yeast extract, and 0.5% NaClBacterial E.coli growth media: LB Miller broth/LBLennox brothLB broth is the most commonly used medium in molecular biology for E.coli cell culture. Easy to make, fast growth rate of most E.coli strains, readily available andsimple compositions contribute the popularity of LB broth. LB broth contains the enzymatic digestion product of casein commonly known as peptone (some vendors term it Tryptone), yeast extract, and sodium chloride. Peptone is rich in amino acids and peptides. Its amino acid and peptide compositions reflect those of casein. In addition to amino acids and peptides, yeast extract also contains nucleic acids, lipids and other nutrients which are needed for bacterial growth. LB can support E.coli growth OD600 2 to 3 under normal shaking incubation condition (250 rpm). The LB Miller Broth and LB Lennox Broth contain higher and lower sodium chloride levels respectively. There are minimal differences between the two formulations in most molecular biology studies with commonly used E.coli strains. Different bacteria strains may require different salt concentrations. The low salt formula is more often used in salt-sensitive antibiotic selections.Bacterial E.coli growth medium SOB 2% peptone, 0.5% Yeast extract, 10mM NaCl, 2.5mM KCl, 10mMMgCl2, 10mM MgSO4注意：氯化镁，硫酸镁可以单独灭菌，但是不能和前面的一起灭，否则可能会形成沉淀。
细菌转化(bacterial transformation)原理和操作
细菌转化（bacterial transformation）原理和操作1．目的学会质粒DNA转化感受态受体菌的技术。
2．原理质粒DNA粘附在细菌细胞表面，经过42°C短时间的热击处理，促进吸收DNA。
然后在非选择培养基中培养一代，待质粒上所带的抗菌素基因表达，就可以在含抗菌素的培养基中生长。
3．器材旋涡混合器，微量移液取样器，移液器吸头，1.5ml 微量离心管，双面微量离心管架，干式恒温气浴（或恒温水浴锅），制冰机，恒温摇床，培养皿（已铺好固体LB-Amp），超净工作台，酒精灯，玻璃涂棒，恒温培养箱。
4．试剂LB培养基（不加抗菌素），LB培养基（加抗菌素），无菌ddH2O，IPTG，X- gal。
5．实验准备无菌ddH2O，1.5ml离心管装入铝制饭盒（灭菌）、移液器吸头装入相应的吸头盒（灭菌），20%IPTG（M/V），2% X-gal（M/V，用N,N-二甲基甲酰胺配）。
6．操作步骤（1）事先将恒温水浴的温度调到42℃。
（2）从-70℃ 超低温冰柜中取出一管（100μl）感受态菌，立即用手指加温融化后插入冰上，冰浴5~10min。
（3）加入5μl连接好的质粒混合液（DNA含量不超过100ng），轻轻震荡后放置冰上20min。
（4）轻轻摇匀后插入42℃水浴中1~2min进行热休克，然后迅速放回冰中，静置3~5min。
（5）在超净工作台中向上述各管中分别加入500μl LB培养基（不含抗菌素）轻轻混匀，然后固定到摇床的弹簧架上37℃震荡1h。
（6）在超净工作台中取上述转化混合液100~300μl，分别滴到含合适抗菌素的固体LB平板培养皿中，用酒精灯烧过的玻璃涂布棒涂布均匀（注意：玻璃涂布棒上的酒精熄灭后稍等片刻，待其冷却后再涂）。
（7）如果载体和宿主菌适合蓝白斑筛选的话，滴完菌液后再在平板上滴加40μl 2% X-gal，8μl 20% IPTG，用酒精灯烧过的玻璃涂布棒涂布均匀。
（8）在涂好的培养皿上做上标记，先放置在37℃恒温培养箱中30-60 min直到表面的液体都渗透到培养基里后，再倒置过来放入37℃恒温培养箱过夜。
Bacterial Communities in Bioreactors
Bacterial Communities in Bioreactors Bacterial communities in bioreactors play a crucial role in various industrial and environmental processes. These communities, also known as biofilms, are complex and dynamic ecosystems consisting of diverse microbial populations. Understanding the composition, structure, and function of these bacterial communities is essential for optimizing bioreactor performance and harnessingtheir potential for biotechnological applications. In this article, we will explore the significance of bacterial communities in bioreactors from multiple perspectives, including their role in wastewater treatment, bioremediation, and bioprocessing. From the perspective of wastewater treatment, bacterial communities in bioreactors are instrumental in removing organic pollutants and nutrients from wastewater. These communities consist of various bacterial species that work synergistically to degrade organic matter and convert nitrogen and phosphorus compounds into less harmful forms. The metabolic activities of these bacteria contribute to the purification of wastewater, making it suitable for discharge or reuse. Moreover, the resilience of these bacterial communities enables them to adapt to fluctuating environmental conditions, ensuring consistent treatment performance over time. This aspect highlights the importance of maintaining a healthy and diverse bacterial community within bioreactors for efficient wastewater treatment. In the context of bioremediation, bacterial communities in bioreactors play a critical role in the degradation of environmental contaminants. Bioremediation processes leverage the metabolic capabilities of bacteria to break down pollutants such as hydrocarbons, heavy metals, and pesticides. By harnessing the diverse enzymatic activities ofdifferent bacterial species, bioreactors can facilitate the transformation of hazardous compounds into less toxic or inert forms. The adaptability of bacterial communities allows them to thrive in contaminated environments and contribute to the restoration of ecosystems. As such, the study and manipulation of these microbial communities are essential for developing effective bioremediation strategies to mitigate environmental pollution. In bioprocessing applications, bacterial communities in bioreactors are utilized for the production of various valuable compounds, including enzymes, biofuels, and pharmaceuticals. Themetabolic diversity of bacterial populations enables the synthesis of a wide range of biochemical products through fermentation processes. By optimizing the composition and dynamics of bacterial communities, bioprocess engineers can enhance product yields, minimize by-product formation, and improve process stability. The intricate interactions within these microbial ecosystems offer opportunities for bioengineering approaches to tailor bacterial communities for specific bioprocessing objectives, ultimately contributing to the sustainable production of bio-based materials. Despite the significant contributions of bacterial communities in bioreactors to various industrial and environmental processes, several challenges and research gaps persist. The complexity of these microbial ecosystems poses difficulties in fully understanding their dynamics and interactions. Furthermore, the influence of operational parameters, such as temperature, pH, and substrate availability, on the stability and performance of bacterial communities requires further investigation. Additionally, the potential emergence of antimicrobial resistance within bioreactor communities raises concerns regarding the long-term sustainability of biotechnological applications reliant on these microbial populations. Addressing these challenges necessitates interdisciplinary efforts encompassing microbiology, bioprocess engineering, environmental science, and bioinformatics. In conclusion, bacterial communities in bioreactors play a multifaceted and indispensable role in various industrial and environmental contexts. Their impact spans from wastewater treatment and bioremediation to bioprocessing, offering diverse opportunities for sustainable resource management and biotechnological innovation. The intricate interplay of microbial species within these communities underscores the need for comprehensive research and technological advancements to harness their potential effectively. By gaining a deeper understanding of bacterial communities in bioreactors and their complex dynamics, we can unlock new possibilities for addressing pressing environmental challenges and advancing bioprocessing capabilities.。
会员群体为商城带来的价值及价值识别模型
2021年第20卷第4期会员群体为商城带来的价值及价值识别模型□马梦影【内容摘要】对于会员群体给商家带来的价值问题，根据中国数据网查到的会员年龄段的分布得出1960 2000年间出生会员人数较多。
运用层次分析法，得出会员与非会员之间是具有显著差异性。
通过对数据处理得到会员的消费金额明显大于非会员的消费金额，会员给商场带来的价值远大于非会员的价值。
对于会员的价值识别问题，根据附件利用EXCEL和SPSS软件对所给的会员销售数量、商品售价、消费金额和会员消费积分等数据进行提取和数据拟合得到每位会员的购买力的模型，通过模型分析发现会员的购买能力大于非会员的购买能力，从而会员可以给商城带来价值。
【关键词】多元线性回归模型；层次分析法；会员群体；价值模型【作者简介】马梦影（1996 ），女，吉林长春人，吉林师范大学数学学院硕士研究生；研究方向：应用数学会员在商场消费中，对于运营商的销售额度和利润，起着很大的帮助，直接或间接地影响到运营商未来的发展方向。
在商场中会员与非会员的来源不同，非会员随意性比较大，忠实度不同，会员对商家有一定的信任度［1］。
而非会员与商家没有任何感情根底。
对于商家会员与非会员的潜在价值与信息发掘也不相同。
会员与非会员享用商家活动政策也不一样等，运用这些信息对会员群体给商场未来的价值加以说明。
关于商场会员的消费特征，分析并比较该商场会员与非会员群体的差异，说明会员群体给商场带来的价值。
对于会员的消费情况建立能够刻画每一位会员购买力的数学模型，以便能够对每个会员的价值进行识别。
一、符号说明B1、B2、B3、B4、B5、B6、B7分别代表年龄特征、商品价格特征、优惠力度特征、商品的市场需求、性别特征、消费者的月收入、商品的实用性。
X1、Y分别代表商品售价、销售金额。
X2、X3均代表消费的会员积分。
二、问题分析针对查阅的数据资料可以得出会员人群中男性人数35 685人，占比19%；女性人数149 641人，占比81%，女性会员人数大于男性会员人数。
两个基因共转导的频率。
• 9.1 Bacterial Mutation and Growth
Bacterial Phenotypes
• To do genetics, we need phenotypic variation. • Prior to1943 • The adaptation hypothesis, • spontaneous mutations Morphology/resistance/prototroph(autotroph)/
• In the nonintegrated state, F can pass into F-free cells during cell conjugation.
• When F is integrated, the bacterial chromosome is transferred linearly to an F-free cell during conjugation.
9.1 Bacterial Mutation and Growth Genetic 9.2 Recombination in Bacteria: Conjugation 9.3 Rec Proteins and Bacterial
Recombination 9.4 F Factors and Plasmids 9.5 Bacterial Transformation 9.6 The Genetic Study of Bacteriophages
• During specialized transduction, specific genes near the phage-integration sites on the bacterial chromosome are mistakenly incorporated into the phage genome and transferred to other cells by infection.
转座因子介绍
a） 通过反义RNA的翻译水平控制
◘ IS10R外侧边缘两个启动子 ◘ PIN控制IS10R的转录 弱启动子 ◘ POUT—强启动子 右向转录宿主DNA ◘ INRNA和OUTRNA
有36bp的重叠
稳定性： OUTRNA››INRNA
◘ 大量OUTRNA作为
INRNA的反义RNA >5拷贝
b） 甲基化作用控制转座酶合成及其与DNA的结合
150bp 1.5kb
att L C
A
B
S
U
att R
以E.coli为寄主的温和型噬菌体（溶源、裂解）
150bp 1.5kb
P att L C
A
B
S
U
att R gin
G 倒位区 38kb
C repressor for A, B B 33 kd 与转座有关 A 70 kd 转座酶 U, S 毒性蛋白 attL, attR 与寄主同源，反向重复，转座必需 Gin G区倒位酶
转座过程： n 转座酶（transposase）催化IS的转座，它由IS编码。 n 首先转座酶交错切开宿主靶位点，然后IS插入，与 宿主的单链末端相连接，余下的缺口由DNA聚合酶 和连接酶加以填补，最终插入的IS两端形成了DR或 靶重复。
若IS插入到某基因内，通常这个基因就会失活， 发生基因突变。 不同IS的插入方向不同，基因突变的结果不同:
homework
• 一、名词解释 • 1.插入序列(IS) 2.转座子 3. 转座噬菌体
二、简答题 • 1.描述两种转座子引起基因组重排的方式。 • 2.IS元件整合到靶位点时会发生什么? • 3.一个复合转座子和一个IS元件之间的关系 是什么?。 • 4.列出一个转座子插入到一个新位点所要求 的步骤. • 。
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Overall Transformation Process
1. The plasmid vector must be cut with a restriction endonuclease (aka: restriction enzyme) 2. DNA ligase joins the DNA fragment & vector DNA 3. Host cell is made competent so can plasmid can enter 4. Transformed cells are grown on selection media
Transformation Applications
GFP Uses
• Use as a reporter molecule to follow changes in gene expression over time • Nondestructive, nontoxic • Coding sequence can be cloned into a variety of vectors • GFP keeps its fluorescence in cells from different species • Can be tracked in living cells over to time to study development • Can be directed to specific subcellular compartments • Can combine GFP coding region with the regulatory region for another gene and observe changes in gene expression • Can be used to make a fusion protein to study localization, turnover & intracellular associations of native protein • GFP gene is switched on when cells are grown in the presence of arabinose
Overall Transformation Process
1. The plasmid vector must be cut with a restriction endonuclease (aka: restriction enzyme) 2. DNA ligase joins the DNA fragment & vector DNA 3. Host cell is made competent so can plasmid can enter 4. Transformed cells are grown on selection media
Transformation of Bacteria
• Generally occurs through heat shock and addition of a divalent cation to permeabilize the membrane • Competent cells are those capable of taking up the plasmid
Overall Transformation Process
1. The plasmid vector must be cut with a restriction endonuclease (aka: restriction enzyme) 2. DNA ligase joins the DNA fragment & vector DNA 3. Host cell is made competent so can plasmid can enter 4. Transformed cells are grown on selection media
Bacterial Transformation
RET Summer 2007
Overall Picture
Bio-Rad pGLO Transformation
Insertion of GFP gene into HB101 E. coli
Transformation
• The process of transferring foreign DNA fragments into a recipient (host) cell for growth and replication • Our host cells: HB101 E. coli • Our foreign DNA: GFP & b-lactamase genes (contained in the pGLO plasmid)
Overall Transformation Process
1. The plasmid vector must be cut with a restriction endonuclease (aka: restriction enzyme) 2. DNA ligase joins the DNA fragment & vector DNA 3. Host cell is made competent so can plasmid can enter 4. Transformed cells are grown on selection media
Restriction Enzymes
• Endonucleases: – in nature, they protect bacteria from intruding DNA – cut up (restrict) the viral DNA – cut only at very specific nucleotide sequences • Restriction site: recognition sequence for a particular restriction enzyme • Restriction fragments: segments of DNA cut by restriction enzymes in a reproducible way • DNA ligase: joins the sticky ends of DNA fragments
• Plasmid copy number • Host strain used, carbohydrate production • Culture medium, selection, and culture time
– Want to harvest during log growth phase
Selection
• A selective medium is used to determine which bacterial cells contain the antibiotic resistant plasmid insert and which do not • For example, a bacterium containing a plasmid with resistance to a particular antibiotic (ampicillin) will grow on medium that contains that antibiotic • In addition, our plasmid contains a regulatory element that activates the GFP gene only in the presence of arabinose
Selection Media
LB plates: Control (-pGLO) LB + amp: Should contain only cells with the ampresistant pGLO plasmid; colonies appear white (-pGLO, + p3; ara: Should contain only cells with the amp-resistant pGLO plasmid; colonies floresce green (+pGLO)
Factors that Affect Yield and Quality of Plasmid DNA
Plasmids
• Plasmids
– small (1-1000 kb) – circular – extrachromosomal DNA
• Growth is independent of the host’s cell cycle; amplification of gene product • A type of cloning vector used to carry a gene not found in the bacterial host’s chromosome