1。 DNA定量的程序<ol><li>打开仪器。 </li><li> BioSpec纳米软件从PC桌面上打开。 </li><li>点击简单核酸双链DNA标签（图1）。 </li><li>该软件将建立与仪器的通信和运行初始化序列。这验证，该仪器是按规范进行。 </li><li>选择0.7或0.2毫米的光程滑块。这种选择的光程，所有的计算都基于所选择的路径长度。 </li><li> BioSpec纳米软件，请点击设置Autowiping设置下一步。选择1或2。 </li><li>加入2μL（0.7毫米）H 2 O或底座上的缓冲区。 </li><li>点击空白的空白测量或F6。每次选择一个新的光程是要记录一个空白。 </li><li>加入2μL的样品基座上。 </li><li>单击“开始在软件或按下仪器上的启动按钮。上面的窗口移动，使样品液滴的接触。氙弧灯可以观察到。 </li><li>同一样品重复3次，以确定可重复性。 </li><li>所有的数据记录保存。芽文件。 </li><li>要保存为PDF或CSV文件。，单击“保存PDF / CSV或F9键。结果也可以保存为。csv文件，使用适当的选择“保存”选项卡。 </li></ol> 2。蛋白质定量议定书“ <ol><li>选择蛋白定量选项卡（图2）。 </li><li>输入消光系数E280，如果知道的话。 </li><li>如果不知道E280计算使用e280Calc。 </li><li>选择0.7或0.2毫米的光程滑块。 </li><li>点击安装Autowiping设置。选择2个或以上。 </li><li>移取3μL（0.2毫米）H 2 O或底座上的缓冲。 </li><li>点击空白的空白测量或F6。 </li><li>移取3μL蛋白质样品基座。 </li><li>单击“开始在软件或按下仪器上的启动按钮。 </li><li>同一样品重复3次，以确定可重复性。 </li><li>记录所有的数据将被保存为。芽文件</li><li>要保存为PDF或CSV文件。，单击“保存PDF / CSV或F9键。 </li></ol> 3。代表性的成果： 1。 DNA定量结果图3显示了一个典型的双链DNA样本的测量数据。也显示浓度和OD 260/280比值计算。图4包含DNA定量的测试结果的重复性。在图3和图4显示了结果的数据是非常明显低的相对标准偏差为0.26％重复性。 注1： DNA定量不准确，可能会出现缓冲液成分的存在，这可能在紫外区的吸收。也有必要使用一个同质的样品溶液。由于吸管样本量只有1-2微升，准确卷小心吹打没有出台任何气泡是必需的。 2。蛋白质定量结果图5表示蛋白质BSA浓度的分析。 μg/ mL的蛋白浓度是基于E280价值。图6显示了可重复性的分析。 BioSpec纳米措施浓度精确 - 不仅对DNA也为蛋白质，这是显而易见的，相对标准偏差为0.51％的。 注2：蛋白质浓度的影响因素精确的蛋白浓度测定是可行的，当有不稳定的最低pH值，缓冲液，温度，或添加剂造成的影​​响。大多数纯化的蛋白质经过加工的各个步骤，因此它是可能的，该蛋白可能包含表面活性剂或其他添加剂，可能会干扰与液滴的形成。对于这样的样品，用5毫米光程的石英细胞是强烈建议。 <img src="/files/ftp_upload/2699/2699fig1.jpg" alt="图1" /> 图1双链DNA定量的分析物的选择窗口。 <img src="/files/ftp_upload/2699/2699fig2.jpg" alt="图2" /> 图2分析物非标记的蛋白质定量选择窗口。 <img src="/files/ftp_upload/2699/2699fig3.jpg" alt="图3" /> DNA定量有代表性的数据图3。 <img src="/files/ftp_upload/2699/2699fig4.jpg" alt="图4" /> 图4。重复性DNA定量数据<img src="/files/ftp_upload/2699/2699fig5.jpg" alt="图5" /> 蛋白质定量的有代表性的数据图5 。 <img src="/files/ftp_upload/2699/2699fig6.jpg"ALT =“图6”/&gt; 图6。蛋白质定量的重复性数据

<ol>
	<li>Aisubel, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Short Protocols in Molecular Biology. , (1999).</li><li>Pace, C. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+to+measure+and+predict+molar+absorption+coefficient+of+a+protein.">How to measure and predict molar absorption coefficient of a protein.</a> Protein Science. 4, 2411-2423 .</li></ol>

Suja Sukumaran，博士是谁在这篇文章中精选仪器日本岛津公司的雇员。

BioSpec -纳米经过精心设计，以解决目前在DNA定量方法的固有问题，如不一致的结果和繁琐的手工劳动，。每次测量只需3秒，让经验丰富的分子生物学家分析多个样品约3-6分钟。独特的雨刮器功能，不仅提高了测量的吞吐量，同时也消除了手工清洗基座的需要，造成测量之间可以忽略不计结转。此外，测试使用的DNA样本包含1000纳克/μL仅2湿巾，表示结转小于2纳克/μL。 一个5毫米的光程细胞的可用性提供了一个选项分析稀核酸和蛋白样品，并扩展其他应用程序使用此仪器。

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">	
		
		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>BioSpec-nano</td>
<td>&nbsp;</td>
<td>Shimadzu</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Calf Thymus DNA</td>
<td>&nbsp;</td>
<td>Sigma Aldrich</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Bovine Serum Albumin</td>
<td>&nbsp;</td>
<td>Sigma Aldrich</td>
<td>&nbsp;</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>

concentration determination of nucleic acids and proteins using the micro-volume bio-spec nano spectrophotometer

在过去三十年，拥有先进的核酸定量程序明显。越来越多，分子生物学家需要小批量的分析，他们的实验中核酸样品一致。 BioSpec纳米不准确的，非重复性的结果，在当前的DNA定量方法所固有的，通过专门的光学和一个敏感的PDA检测器的问题提供了一个潜在的解决方案。 BioSpec - nano还具有自动化功能，例如，安装，测量和清洁仪器，从而省去繁琐，重复和不一致的光纤元素和手工清洗的位置。 在这项研究中，DNA和蛋白质，以及测量的可重复性和准确性的量化数据呈现。自动样品接触和快速扫描可以在三秒钟内测量，造成出色的吞吐量。使用该软件的内置功能进行数据分析。用于计算DNA浓度的计算公式为： 样品的浓度= DF（OD260 - OD320）·农协（1） 凡DF =样品稀释倍数和农协=核酸浓度的因素。 按照选定1待测核酸浓度的因素。 可以表示为μg/ mL的蛋白浓度结果或进入E280和分子量值分别为痣/大号。当在e280Calc选项卡中输入的酪氨酸，色氨酸和半胱氨酸（二硫键）的残留值，消光系数的计算值作为E280 = 5500 ×（Trp残基）+ 1490 ×（Tyr残基）+ 125 ×（半胱氨酸二硫键） 。 E280的价值是用浓度计算软件。 BioSpec纳米除核酸和蛋白质浓度测定，可用于许多其他分析超微量分光光度计，或用5毫米光程细胞作为一个标准的分光光度计。

Watch this Scientific Journal Video about Concentration Determination of Nucleic Acids and Proteins Using the Micro-volume Bio-spec Nano Spectrophotometer at JoVE.com

Concentration Determination of Nucleic Acids and Proteins Using the Micro-volume Bio-spec Nano Spectrophotometer

这种沟通的BioSpec纳米的紫外 - 可见分光光度计双链DNA和蛋白质定量的准确性和可重复性的数据。即使与超小卷（1〜2 L），重现性优良，自动擦拭功能，同时可以提高吞吐量和更精确的结果最小结转结果。

使用微量的生物规格的纳米分光光度计核酸和蛋白的浓度测定

Nucleic Acid quantitation procedures have advanced significantly in the last three decades.  More and more, molecular biologists require consistent ...

concentration-determination-nucleic-acids-proteins-using-micro-volume

Research

JoVE Journal

Biology

38.9K 次观看.  Scientific Instruments. 这种沟通的BioSpec纳米的紫外 - 可见分光光度计双链DNA和蛋白质定量的准确性和可重复性的数据。即使与超小卷（1〜2 L），重现性优良，自动擦拭功能，同时可以提高吞吐量和更精确的结果最小结转结果。

视频: Concentration Determination of Nucleic Acids and Proteins Using the Micro-volume Bio-spec Nano Spectrophotometer

Microvolume Protein Concentration Determination using the NanoDrop 2000c Spectrophotometer

Traditional spectrophotometry requires placing samples into cuvettes or capillaries. This is often impractical due to the limited sample volumes often used for protein analysis. The Thermo Scientific NanoDrop 2000c Spectrophotometer solves this issue with an innovative sample retention system that holds microvolume samples between two measurement surfaces using the surface tension properties of liquids, enabling the quantification of samples in volumes as low as 0.5-2 &mu;L. The elimination of cuvettes or capillaries allows real time changes in path length, which reduces the measurement time while greatly increasing the dynamic range of protein concentrations that can be measured. The need for dilutions is also eliminated, and preparations for sample quantification are relatively easy as the measurement surfaces can be simply wiped with laboratory wipe. This video article presents modifications to traditional protein concentration determination methods for quantification of microvolume amounts of protein using A280 absorbance readings or the BCA colorimetric assay.

Microvolume samples are quantified by a spectrophotometer system that uses natural surface tension to retain samples without the use of cuvettes or capillaries. The dynamic range of protein concentrations and speed by which they can be measured are greatly increased with this method.

微量法测定蛋白浓度使用NanoDrop 2000C分光光度计

Traditional spectrophotometry requires placing samples into cuvettes or capillaries. This is often impractical due to the limited sample volumes often ...

科研

生物学

Crystallizing Membrane Proteins for Structure Determination using Lipidic Mesophases

A detailed protocol for crystallizing membrane proteins by using lipidic mesophases is described. This method has variously been referred to as the lipidic cubic phase or in meso method. The method has been shown to be quite versatile in that it has been used to solve X-ray crystallographic structures of prokaryotic and eukaryotic proteins, proteins that are monomeric, homo- and hetero-multimeric, chromophore-containing and chromophore-free, and alpha-helical and beta-barrel proteins. Recent successes using in meso crystallization are the human engineered beta2-adrenergic and adenosine A2a G protein-coupled receptors. Protocols are presented for reconstituting the membrane protein into the monoolein-based mesophase, and for setting up crystallizations in the manual mode. Additional steps in the overall process, such as crystal harvesting, are to be addressed in future video articles. The time required to prepare the protein-loaded mesophase and to set up a crystallization plate manually is about one hour.

Herein is described the procedure implemented in the Caffrey Membrane Structural and Functional Biology Group to set up manually crystallization trials of membrane proteins in lipidic mesophases.

使用油脂介孔结构的测定结晶膜蛋白

A detailed protocol for crystallizing membrane proteins by using lipidic mesophases is described. This method has variously been referred to as the ...

The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis 

In this study, we explore the interaction between the bovine cysteine protease inhibitor cystatin B and a catalytically inactive form of papain (Fig. 1), a plant cysteine protease, by real-time label-free analysis using Biacore X100. Several cystatin B variants with point mutations in areas of interaction with papain, are produced. For each cystatin B variant we determine its specific binding concentration using calibration-free concentration analysis (CFCA) and compare the values obtained with total protein concentration as determined by A280. After that, the kinetics of each cystatin B variant binding to papain is measured using single-cycle kinetics (SCK). We show that one of the four cystatin B variants we examine is only partially active for binding. This partial activity, revealed by CFCA, translates to a significant difference in the association rate constant (ka) and affinity (KD), compared to the values calculated using total protein concentration. Using CFCA in combination with kinetic analysis in a structure-function study contributes to obtaining reliable results, and helps to make the right interpretation of the interaction mechanism.

The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis

We apply label-free protein interaction analysis using Biacore X100 for structure-function analysis of the binding of several cystatin B mutants to papain through kinetic characterization. Calibration-free concentration analysis (CFCA) measures the concentration of protein with retained binding activity without the need for a standard curve. We show that confirmation of concentrations using CFCA increases the reliability of the kinetic analysis and that kinetic constants can reliably be determined even if the activity of a recombinant protein is reduced.

正确的蛋白浓度的动力学结构与功能分析和亲和力测定的重要性

In this study, we explore the interaction between the bovine cysteine protease inhibitor cystatin B and a catalytically inactive form of papain (Fig. 1), ...

Quantification of dsDNA using the Hitachi F-7000 Fluorescence Spectrophotometer and PicoGreen Dye

Quantification of DNA, especially in small concentrations, is an important task with a wide range of biological applications including standard molecular biology assays such as synthesis and purification of DNA, diagnostic applications such as quantification of DNA amplification products, and detection of DNA molecules in drug preparations. During this video we will demonstrate the capability of the Hitachi F-7000 Fluorescence Spectrophotometer equipped with a Micro Plate Reader accessory to perform dsDNA quantification using Molecular Probes Quant-it PicoGreen dye reagent kit.
The F-7000 Fluorescence Spectrophotometer offers high sensitivity and high speed measurements. It is a highly flexible system capable of measuring fluorescence, luminescence, and phosphorescence. Several measuring modes are available, including wavelength scan, time scan, photometry and 3-D scan measurement. The spectrophotometer has sensitivity in the range of 50 picomoles of fluorescein when using a 300 &#956;L sample volume in the microplate, and is capable of measuring scan speeds of 60,000 nm/minute. It also has a wide dynamic range of up to 5 orders of magnitude which allows for the use of calibration curves over a wide range of concentrations. The optical system uses all reflective optics for maximum energy and sensitivity. The standard wavelength range is 200 to 750 nm, and can be extended to 900 nm when using one of the optional near infrared photomultipliers. The system allows optional temperature control for the plate reader from 5 to 60 degrees Celsius using an optional external temperature controlled liquid circulator. The microplate reader allows for the use of 96 well microplates, and the measuring speed for 96 wells is less than 60 seconds when using the kinetics mode.
Software controls for the F-7000 and Microplate Reader are also highly flexible. Samples may be set in either column or row formats, and any combination of wells may be chosen for sample measurements. This allows for optimal utilization of the microplate. Additionally, the software allows importing micro plate sample configurations created in Excel and saved in comma separated values, or "csv" format. Microplate measuring configurations can be saved and recalled by the software for convenience and increased productivity. Data results can be output to a standard report, to Excel, or to an optional Report Generator Program.

Demonstration of quantification of dsDNA using Molecular Probes PicoGreen dye and Hitachi F-7000 Fluorescence Spectrophotometer equipped with a microplate reader accessory.

双链DNA定量，使用日立F - 7000荧光分光光度计和PicoGreen染料

Quantification of DNA, especially in small concentrations, is an important task with a wide range of biological applications including standard molecular ...

NanoDrop Microvolume Quantitation of Nucleic Acids

Biomolecular assays are continually being developed that use progressively smaller amounts of material, often precluding the use of conventional cuvette-based instruments for nucleic acid quantitation for those that can perform microvolume quantitation.
The NanoDrop microvolume sample retention system (Thermo Scientific NanoDrop Products) functions by combining fiber optic technology and natural surface tension properties to capture and retain minute amounts of sample independent of traditional containment apparatus such as cuvettes or capillaries. Furthermore, the system employs shorter path lengths, which result in a broad range of nucleic acid concentration measurements, essentially eliminating the need to perform dilutions. Reducing the volume of sample required for spectroscopic analysis also facilitates the inclusion of additional quality control steps throughout many molecular workflows, increasing efficiency and ultimately leading to greater confidence in downstream results.
The need for high-sensitivity fluorescent analysis of limited mass has also emerged with recent experimental advances. Using the same microvolume sample retention technology, fluorescent measurements may be performed with 2 &mu;L of material, allowing fluorescent assays volume requirements to be significantly reduced. Such microreactions of 10 &mu;L or less are now possible using a dedicated microvolume fluorospectrometer.
Two microvolume nucleic acid quantitation protocols will be demonstrated that use integrated sample retention systems as practical alternatives to traditional cuvette-based protocols. First, a direct A260 absorbance method using a microvolume spectrophotometer is described. This is followed by a demonstration of a fluorescence-based method that enables reduced-volume fluorescence reactions with a microvolume fluorospectrometer. These novel techniques enable the assessment of nucleic acid concentrations ranging from 1 pg/ &mu;L to 15,000 ng/ &mu;L with minimal consumption of sample.

The use of NanoDrop microvolume systems as practical and efficient alternatives to traditional nucleic acid quantitation methodology is described through the demonstration of two microvolume nucleic acid quantitation protocols.

NanoDrop微量核酸的定量

Biomolecular assays are continually being developed that use progressively smaller amounts of material, often precluding the use of conventional ...

Analyzing and Building Nucleic Acid Structures with 3DNA

The 3DNA software package is a popular and versatile bioinformatics tool with capabilities to analyze, construct, and visualize three-dimensional nucleic acid structures. This article presents detailed protocols for a subset of new and popular features available in 3DNA, applicable to both individual structures and ensembles of related structures. Protocol 1 lists the set of instructions needed to download and install the software. This is followed, in Protocol 2, by the analysis of a nucleic acid structure, including the assignment of base pairs and the determination of rigid-body parameters that describe the structure and, in Protocol 3, by a description of the reconstruction of an atomic model of a structure from its rigid-body parameters. The most recent version of 3DNA, version 2.1, has new features for the analysis and manipulation of ensembles of structures, such as those deduced from nuclear magnetic resonance (NMR) measurements and molecular dynamic (MD) simulations; these features are presented in Protocols 4 and 5. In addition to the 3DNA stand-alone software package, the w3DNA web server, located at <a href="http://w3dna.rutgers.edu" target="_blank">http://w3dna.rutgers.edu</a>, provides a user-friendly interface to selected features of the software. Protocol 6 demonstrates a novel feature of the site for building models of long DNA molecules decorated with bound proteins at user-specified locations.

The 3DNA software package is a popular and versatile bioinformatics tool with capabilities to analyze, construct, and visualize three-dimensional nucleic acid structures. This article presents detailed protocols for a subset of new and popular features available in 3DNA, applicable to both individual structures and ensembles of related structures.

核酸结构分析及建设3DNA

The 3DNA software package is a popular and versatile bioinformatics tool with capabilities to analyze, construct, and visualize three-dimensional nucleic ...

Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues

S-Adenosyl-l-methionine (AdoMet or SAM)-dependent methyltransferases (MTase) catalyze the transfer of the activated methyl group from AdoMet to specific positions in DNA, RNA, proteins and small biomolecules. This natural methylation reaction can be expanded to a wide variety of alkylation reactions using synthetic cofactor analogues. Replacement of the reactive sulfonium center of AdoMet with an aziridine ring leads to cofactors which can be coupled with DNA by various DNA MTases. These aziridine cofactors can be equipped with reporter groups at different positions of the adenine moiety and used for Sequence-specific Methyltransferase-Induced Labeling of DNA (SMILing DNA). As a typical example we give a protocol for biotinylation of pBR322 plasmid DNA at the 5&#8217;-ATCGAT-3&#8217; sequence with the DNA MTase M.BseCI and the aziridine cofactor 6BAz in one step. Extension of the activated methyl group with unsaturated alkyl groups results in another class of AdoMet analogues which are used for methyltransferase-directed Transfer of Activated Groups (mTAG). Since the extended side chains are activated by the sulfonium center and the unsaturated bond, these cofactors are called double-activated AdoMet analogues. These analogues not only function as cofactors for DNA MTases, like the aziridine cofactors, but also for RNA, protein and small molecule MTases. They are typically used for enzymatic modification of MTase substrates with unique functional groups which are labeled with reporter groups in a second chemical step. This is exemplified in a protocol for fluorescence labeling of histone H3 protein. A small propargyl group is transferred from the cofactor analogue SeAdoYn to the protein by the histone H3 lysine 4 (H3K4) MTase Set7/9 followed by click labeling of the alkynylated histone H3 with TAMRA azide. MTase-mediated labeling with cofactor analogues is an enabling technology for many exciting applications including identification and functional study of MTase substrates as well as DNA genotyping and methylation detection.

DNA and proteins are sequence-specifically labeled with affinity or fluorescent reporter groups using DNA or protein methyltransferases and synthetic cofactor analogues. Depending on the cofactor specificity of the enzymes, aziridine or double activated cofactor analogues are employed for one- or two-step labeling.

核酸，蛋白质与甲基转移和辅酶类似物序列特异性标签

S-Adenosyl-l-methionine (AdoMet or SAM)-dependent methyltransferases (MTase) catalyze the transfer of the activated methyl group from AdoMet to specific ...

Residue-specific Incorporation of Noncanonical Amino Acids into Model Proteins Using an Escherichia coli Cell-free Transcription-translation System

The canonical set of amino acids leads to an exceptionally wide range of protein functionality. Nevertheless, the set of residues still imposes limitations on potential protein applications. The incorporation of noncanonical amino acids can enlarge this scope. There are two complementary approaches for the incorporation of noncanonical amino acids. For site-specific incorporation, in addition to the endogenous canonical translational machineries, an orthogonal aminoacyl-tRNA-synthetase-tRNA pair must be provided that does not interact with the canonical ones. Consequently, a codon that is not assigned to a canonical amino acid, usually a stop codon, is also required. This genetic code expansion enables the incorporation of a noncanonical amino acid at a single, given site within the protein. The here presented work describes residue-specific incorporation where the genetic code is reassigned within the endogenous translational system. The translation machinery accepts the noncanonical amino acid as a surrogate to incorporate it at canonically prescribed locations, i.e., all occurrences of a canonical amino acid in the protein are replaced by the noncanonical one. The incorporation of noncanonical amino acids can change the protein structure, causing considerably modified physical and chemical properties. Noncanonical amino acid analogs often act as cell growth inhibitors for expression hosts since they modify endogenous proteins, limiting in vivo protein production. In vivo incorporation of toxic noncanonical amino acids into proteins remains particularly challenging. Here, a cell-free approach for a complete replacement of L-arginine by the noncanonical amino acid L-canavanine is presented. It circumvents the inherent difficulties of in vivo expression. Additionally, a protocol to prepare target proteins for mass spectral analysis is included. It is shown that L-lysine can be replaced by L-hydroxy-lysine, albeit with lower efficiency. In principle, any noncanonical amino acid analog can be incorporated using the presented method as long as the endogenous in vitro translation system recognizes it.

Residue-specific Incorporation of Noncanonical Amino Acids into Model Proteins Using an Escherichia coli Cell-free Transcription-translation System

An easy-to-use, cell-free expression protocol for the residue-specific incorporation of noncanonical amino acid analogs into proteins, including downstream analysis, is presented for medical, pharmaceutic, structural and functional studies.

非经典氨基酸的具体残留纳入到模型蛋白质使用<em&gt;大肠杆菌</em&gt;无细胞转录翻译系统

The canonical set of amino acids leads to an exceptionally wide range of protein functionality. Nevertheless, the set of residues still imposes ...

Filtration Isolation of Nucleic Acids:  A Simple and Rapid DNA Extraction Method

FINA, filtration isolation of nucleic acids, is a novel extraction method which utilizes vertical filtration via a separation membrane and absorbent pad to extract cellular DNA from whole blood in less than 2 min. The blood specimen is treated with detergent, mixed briefly and applied by pipet to the separation membrane. The lysate wicks into the blotting pad due to capillary action, capturing the genomic DNA on the surface of the separation membrane. The extracted DNA is retained on the membrane during a simple wash step wherein PCR inhibitors are wicked into the absorbent blotting pad. The membrane containing the entrapped DNA is then added to the PCR reaction without further purification. This simple method does not require laboratory equipment and can be easily implemented with inexpensive laboratory supplies. Here we describe a protocol for highly sensitive detection and quantitation of HIV-1 proviral DNA from 100 &#181;l whole blood as a model for early infant diagnosis of HIV that could readily be adapted to other genetic targets.

We describe here a simple and rapid paper-based DNA extraction method of HIV proviral DNA from whole blood detected by quantitative PCR. This protocol can be extended for use in detecting other genetic markers or using alternative amplification methods.

核酸的分离过滤：一种简单快速的DNA提取方法

FINA, filtration isolation of nucleic acids, is a novel extraction method which utilizes vertical filtration via a separation membrane and absorbent pad ...

Determination of Sialic Acids in Liver and Milk Samples of Wild-type and CMAH Knock-out Mice.

CMAH (cytidine monophosphate-N-acetylneuraminic acid hydroxylase) is responsible for the oxidation of cytidine monophosphate-N-acetylneuraminic acids in mammals. However, humans cannot oxidize cytidine monophosphate-N-acetylneuraminic acid to cytidine monophosphate-N-glycolylneuraminic acid due to a primary exon deletion of the CMAH gene. To understand the effects and implications of the lack of CMAH activity in more detail, a Cmah knock-out model in mice is of keen interest in basic and applied research. The analysis method to determine the phenotype of this mouse model is herein described in detail, and is based on the detection of both N-acetylneuraminic acid and N-glycolylenuraminic acid in the liver and milk of wild-type and Cmah knock-out mice. Endogenous sialic acids are released and derivatized with o-phenylenediamine to generate fluorogenic derivatives, which can be subsequently analyzed by HPLC. The presented protocol can be also applied for the analysis of milk and tissue samples from various other origins, and may be of use to investigate the nutritional and health effects of N-glycolylneuraminic acid.

Determination of Sialic Acids in Liver and Milk Samples of Wild-type and CMAH Knock-out Mice.

We describe a HPLC-based method for the determination of N-acetylneuraminic acid and N-glycolylenuraminic acid in mouse liver and milk.

测定野生型肝脏和牛奶样品中的唾液酸<em&gt; CMAH</em&gt;敲出小鼠

CMAH (cytidine monophosphate-N-acetylneuraminic acid hydroxylase) is responsible for the oxidation of cytidine monophosphate-N-acetylneuraminic acids in ...