全部

在自然条件下，很多质粒都可通过细菌接合作用转移到新的宿主内，但在人工构建的质粒载体中，一般缺乏此种转移所必需的mob基因，因此不能自行完成从一个细胞到另一个细胞的接合转移。如需将质粒载体转移进受体细菌，需诱导受体细菌产生一种短暂的感受态以摄取外源DNA 。

alimama_pid="mm_10043573_137377_1822161"; alimama_titlecolor="FF9900"; alimama_descolor ="552c55"; alimama_bgcolor="f7f7f7"; alimama_bordercolor="f7f ...

常规片断级的选择指南： 所谓常规级，即回收片段大小介于100bp和10kb之间，在这个范畴内包含了一般的质粒或者克隆片段的回收。主流方法是柱回收试剂盒。 1. Qiaquick Gel Extraction Kit 品牌：Qiagen 回收范围：70bp-10kb 特点： 高达80%回收率 操作快速简单，3步完成70bp-10kb片段的回收 提供三色指示剂的电泳上样loading Bu ...

alimama_pid="mm_10043573_137377_1822161"; alimama_titlecolor="FF9900"; alimama_descolor ="552c55"; alimama_bgcolor="f7f7f7"; alimama_bordercolor="f7f ...

第一节 概 述 PCR (Polymerase Chain Reaction，聚合酶链反应)是一种选择性体外扩增DNA 或RNA的方法。它包括三个基本步骤: (1) 变性(Denature):目的双链DNA 片段在94℃下解链; (2) 退火(Anneal):两种寡核苷酸引物在适当温度(50℃左右)下与模板上的目的序列通过氢键配对;(3) 延伸(Extension):在Taq DNA 聚合酶合成D ...

SNPs(single nucleotide polymorphism ， SNP ，发音为 “snips”) 主要是指在基因组水平上由单个核苷酸的变异所引起的 DNA 序列多态性。它是人类可遗传的变异中最常见的一种。占所有已知多态性的 90% 以上。 SNP 在人类基因组中广泛存在，平均每 500 ～ 1000 个碱基对中就有 1 个，估计其总数可达 300 万个甚至更多 ...

alimama_pid="mm_10043573_137377_1822161"; alimama_titlecolor="FF9900"; alimama_descolor ="552c55"; alimama_bgcolor="f7f7f7"; alimama_bordercolor="f7f ...

TA Cloning exploits the terminal transferase activity of some DNA polymerases such as Taq polymerase. This enzyme adds a single, 3'-A overhang to each end of the PCR product. This makes it possible to clone this PCR product directly into a linearized cloning vector with single, 3'-T overhangs. The PCR products with dA overhang, are mixed with this vector in high proportion. The complementary overhangs of "T" vector and PCR product will be ligated under the action of T4 DNA ligase.

UV shadowing is a technique for visualizing nucleic acids separated on acrylamide/urea gels. The technique utilizes shortwave UV light (254 nm) and a fluor-coated TLC plate. We recommend UV shadowing as the method of choice for gel purification of nonisotopic probes synthesized with Ambion's MAXIscript™ and BrightStar™ Psoralen-Biotin Kits. The alternative to UV shadowing is staining with ethidium bromide or acridine orange and requires subsequent extraction of the dye. The detection limit of UV

The pGL3 Luciferase Reporter Vectors provide a basis for the quantitative analysis of factors that potentially regulate mammalian gene expression. These factors may be cis-acting, such as promoters and enhancers, or trans-acting, such as various DNA-binding factors. The backbone of t ...

Salmon Sperm DNA1.Dissolve 1 g salmon sperm DNA in 100 ml H2 O. 2.Autoclave (20 minutes) and aliquot in 1 ml/tube 3.Store at -20℃. (common freezer for stock solutions)

酵母 菌基因组 DNA的提取 一：仪器： 同方法一 二：试剂： SE缓冲液（1M山梨醇，0.1MEDTA pH7.5）；溶菌酶（50mg/ml）；20％PVP；蛋白酶K缓冲液（10mM Tris pH7.6 0.5% SDS 1mM EDTA）；其余同前 三：操作 1.5ml 对数生长期细菌细胞 离心，12000rpm，1-2min 沉淀 溶于590ulSE缓冲液中混匀+1 ...

macerate tissue in Eppendorf tube without butter at RT add 400 m l extraction buffer vortex for 4 sec leave sample at RT until other samples are ready (> 1 h) spin in microfuge for 1 min transfer 300 m l of supernatant to different Eppendorf tube (prefilled with 300 m l isopropanole) mix and leave at RT for 2 min spin for 5 min vacuum dry pellet and take up in 100 m l TE use 1-2.5 m l for PCR Remarks: DNA is stable for one year at 4℃ Solutions: Extraction buffer: 200 mM Tris-HCl pH 7

The principle and procedures of RLGS method was first described by Hatada et al. (1991) and its improvement was described by Asakawa (1996). Basically based on their procedures ...

alimama_pid="mm_10043573_137377_1822161"; alimama_titlecolor="FF9900"; alimama_descolor ="552c55"; alimama_bgcolor="f7f7f7"; alimama_bordercolor="f7f ...

Protocol for Annealing OligonucleotidesOligo Name:Lot Number:Total nmol:Volume of Annealing Buffer added:Oligo Name:Lot Number:Total nmol:Volume of Annealing Buffer added:Annealing Buffer: 10mM Tris, pH 7.5 - 8.0, 50mM NaCl, 1mM EDTA1xTE Buffer: 10mM Tris, pH 7.5 - 8.0,1mM EDTA.1.R ...

FINGERPRINTING PROTOCOL (AGAROSE GEL) * Restriction digests consist of: 15.75 ml ddH2 O 1 µl 10 X buffer B (Boehringer Mannheim) 0.25 µl HindIII (40 U/µl) 3 µl DNA Set up ...

alimama_pid="mm_10043573_137377_1822161"; alimama_titlecolor="FF9900"; alimama_descolor ="552c55"; alimama_bgcolor="f7f7f7"; alimama_bordercolor="f7f7f7"; alimama_linkcolor="552c55"; ...

alimama_pid="mm_10043573_137377_1822161"; alimama_titlecolor="FF9900"; alimama_descolor ="552c55"; alimama_bgcolor="f7f7f7"; alimama_bordercolor="f7f ...

ECK Description This method was suggested in a BRL "Focus" article several years ago (Zeugin & Hartley, 1985). It is a useful way to avoid coprecipitation of proteins and accumulation of salt in the final dried preparation. Protocol 1. Crude preparations: Add 0.5 volumes of 7.5 M NH4OAc. Pure preparations: Add 0.1 volumes of the same. 2. Add an amount of 95% ethanol equal to 2.5 times the new volume. 3. Continue per your favorite protocol. Note that a subsequent BRL article (-, 1982) pointed