PCR和DNA复制的区别

Key Difference – PCR vs DNA复制

DNA replication is a natural process that occurs in living organisms. It involves the production of two identical copies of oneDNA molecule。DNA replication is an extremely important process of biological inheritance. Genetic information is passed from parent to offspring mainly due to the ability of DNA replication. Hence, it is an essential process that occurs in almost all living organisms. This process occurs体内。但是，DNA复制可以通过体外methods as well. Polymerase Chain Reaction (PCR) is one such体外method of DNA replication. PCR is a DNA amplification method performed in laboratories. It produces thousands to millions of copies of DNA from an interested DNA fragment or a gene. There are differences between体内DNA复制和PCR。这key differencebetween these two is thatpcris performed in a PCR machine at maintained temperatures to produce a large number of copies of DNA while DNA replication occurs inside the body at body temperature to produce two identical copies of a single DNA molecule.

内容

1.Overview and Key Difference
2.What is PCR
3.What is DNA Replication
4.Similarities Between PCR and DNA Replication
5。Side by Side Comparison – PCR vs DNA Replication in Tabular Form
6。概括

What is PCR?

聚合酶链反应（PCR）是体外DNA扩增技术通常在分子生物实验室中进行。该方法使数千份的DNA片段能够生产数千份。PCR是由Kary Mullis在1980年引入的。在这项技术中，感兴趣的DNA片段被用作制作副本的模板。酶调用Taq polymeraseis used as theDNA polymerase enzyme, and it will catalyze the synthesis of new strands of the DNA fragment.底漆that are in the PCR mixture will work as the starting points for the fragment extensions. At the end of the PCR reaction, many copies of the sample DNA can be obtained.

PCR混合物中包括制作DNA拷贝所需的所有成分。它们是样品DNA，DNA聚合酶（TAQ聚合酶），引物（forward and reverse primers),核苷酸(building blocks of DNA) and a buffer. PCR reaction is run in a PCR machine, and it should be fed with correct PCR mixture and the correct PCR program. If the reaction mixture and the program are correct, it will produce the required amount of copies of a particular section of DNA from a very small amount of DNA.

这re are three major steps involved in a PCR reaction namely denaturation, primer annealing and strand extension. These three steps occur at three different temperatures. DNA exists as a double-stranded helix. Two strands are bonded by氢键。放大之前，通过给出高温将双链DNA分离。在高温下，双链DNA变性为单链。然后，底漆将带有感兴趣的片段或DNA基因的侧面末端退火。底漆是一小部分单链DNA，与目标序列的末端互补。在退火温度下，在变性样品DNA的侧端处的互补碱基向前和反向引物退火。

When primers are annealed with DNA, Taq polymerase enzyme initiates the synthesis of the new strands by adding nucleotides that are complementary to the template DNA. Taq polymerase is a heat stable enzyme that is isolated from a嗜热细菌called这rmus aquaticus。PCR缓冲液保持TAQ聚合酶作用的最佳条件。重复PCR反应的这三个阶段，以产生所需量的PCR产物。在每个PCR反应中，DNA拷贝的数量倍增。因此，可以在PCR中观察到指数扩增。可以使用PCR产品观察到凝胶电泳由于它在凝胶上产生可见量的DNA量，并且可以纯化用于进一步的研究，例如测序等。

pcris a valuable tool in medical and biological research. Especially in forensic studies, PCR has an immense value since it can amplify DNA for studies from the tiny samples of the criminals and make forensic DNA profiles. PCR is widely used in many areas of the Molecular biology including,基因分型,基因克隆, mutation detection,DNA测序,DNA microarrays和亲子鉴定等。

什么是DNA复制？

DNA复制是指从一个DNA分子中产生两个相同的DNA副本的过程。这是生物遗传的重要过程。DNA复制发生在所有生物体中。应复制父细胞的基因组，以将基因组移入子细胞中。DNA复制过程具有三个主要步骤，称为启动，伸长和终止。这些步骤被不同的酶催化。DNA复制从细胞基因组中称为复制的位置开始。在基因组中，DNA以双链形式存在。这两条线在DNA复制的开头分离，并且由ATP依赖性DNA解旋酶完成。DNA的放松是在开始步骤中发生的主要事件。 By using separated DNA strands as templates, DNA polymerase synthesizes the new complementary strands of the template strands into 5’ to 3’ direction. This is the step called elongation. Termination occurs when the two replication forks meet with each other on the opposite end of the parental chromosome.

除DNA聚合酶外，几种酶，例如DNA原始酶，DNA解旋酶，DNA连接酶和拓扑异构酶都与DNA复制有关。体内DNA复制的一个特征是它产生冈崎片段。一条线不断形成，而另一链则成小块。

What are the Similarities Between PCR and DNA Replication?

• In both PCR and DNA replication, double-stranded DNA is separated from each other.
• 在PCR和DNA复制过程中，复制DNA。
• PCR和DNA复制过程都非常重要。
• In both PCR and DNA replication processes, DNA polymerase enzyme is involved.

PCR和DNA复制之间有什么区别？

pcrvs DNA Replication
PCR是一个体外method of DNA amplification in which thousands to millions of copies of DNA are produced.	DNA复制是一个自然过程，它从一个DNA分子中产生两个相同的DNA副本。
脚步
PCR有三个步骤；变性，底漆退火和链扩展。	DNA复制有三个步骤；启动，伸长和终止。
引物的参与
PCR需要人造底漆。	DNA复制不需要人造底漆。RNA的短片段参与DNA复制。
Denaturing of the Double-Strands
Double strands are separated by applying a high temperature in PCR.	双链通过DNA复制中的酶DNA解旋酶彼此分离。
涉及酶
pcruses Taq polymerase.	DNA复制使用DNA聚合酶。
温度
pcroccurs at three different temperatures inside a machine.	DNA Replication occurs at body temperature within the body of the living organism.
体内或者体外
PCR是一个体外方法。	DNA Replication is an体内方法。

概括–pcrvs DNA复制

DNA复制是从单个DNA分子中产生两个相同的DNA拷贝的过程。它发生在所有生物体中，因为它提供了一种从父母到后代的遗传信息的方法。它由三个酶促催化的步骤组成，即启动，伸长和终止。DNA复制可以在实验室中人为地进行。PCR是从感兴趣的DNA中产生大量DNA副本的一种方法。PCR通常在分子生物实验室中进行，因为它是产生DNA副本的简单方法。这是PCR和DNA复制之间的差异。

Reference:

1.“DNA replication.” Wikipedia, Wikimedia Foundation, 11 Mar. 2018.Available here
2.“聚合酶链反应（PCR）。”美国国家医学图书馆国家生物技术信息中心。Available here
3.“Molecular mechanism of DNA replication.” Khan Academy.Available here

Image Courtesy:

1.’Polymerase chain reaction’By Enzoklop – Own work,(CC BY-SA 3.0)viaCommons Wikimedia
2.’DNA replication split’By I, Madprime,(CC BY-SA 3.0)viaCommons Wikimedia