Key Difference – Blunt vs Sticky End Ligation
Restrictionendonucleasesare specific酶切割双链DNA(dsDNA)。它们也被称为分子生物学中的分子剪刀。限制酶能够识别被称为识别位点和裂解磷酸酯的dsDNA的特定短序列,并且氢键打开双股。由于这些酶的裂解,DNA片段是用不同类型的末端(例如粘性末端和钝端)产生的。DNA连接酶是一种用于分子生物学中的酶,通过形成新键来连接两条邻近的DNA链。该步骤称为连接,根据连接的DNA末端的类型,它们可以称为钝端连接和粘性末端连接。钝器和粘性结扎的关键区别在于blunt end ligation occurs between DNA fragments which contain two blunt ends然而粘性结扎发生在5'和3'的悬垂之间。Compared to blunt end ligation, sticky end ligation is more efficient and stable.
CONTENTS
1。概述和关键差异
2。什么是钝的结扎
3。什么是粘性结扎
4。并排比较 - 钝与粘性结扎
5。Summary
什么是钝的结束?
Some restriction endonucleases can cut the DNA at the opposite bases and produce blunt end DNA fragments. These enzymes are known as blunt end cutters; they cleave straight down to the middle of the restriction site without leaving single stranded overhanging bases. Blunt ends are also known as non-overhanging ends since they do not have 3’ and 5’ overhanging bases at the ends. Both strands terminate from base pairs in blunt ends. Common blunt end cutting enzymes are EcoRV HaeIII, AluI and SmaI.
钝器结束涉及两个钝器之间。这不是突出碱基的连接。这种连接效率不如粘性结扎效率。但是,在某些情况下,钝器结扎比粘末端连接更有利,尤其是在连接时pcr产品。PCR产品始终以钝端生产。钝器结扎不需要DNA中的互补末端进行连接。
什么是粘性结扎?
一些限制性核酸内切酶能够切割dsDNA,最后留下一块悬垂的单链DNA。这些末端被称为粘性或悬垂的末端。粘性末端连接发生在两个含有匹配悬垂的DNA片段之间,因为粘性末端具有未配对的底座,并且需要互补的基础才能形成键。因此,必须使用相同的限制酶来生成匹配的连接片段。
Sticky end ligation is more efficient and is often highly desirable in cloning processes. There are several restriction enzymes which produce sticky ends. They are EcoRI, BamHI, HindIII etc.
钝器和粘性结扎之间有什么区别?
Blunt vs Sticky End Ligation |
|
钝的末端连接发生在两个钝端DNA片段之间。 | 粘性末端连接发生在两个具有粘性末端的匹配的DNA片段之间。 |
酶 | |
Blunt end cutters produce blunt ends. | 粘端切割机会产生粘性或凝聚力的末端。 |
Requirement of Matching Ends | |
它不需要匹配的片段或互补基础。 | 它需要在末端的互补基础以形成碱基对。 |
效率 | |
它的效率不如粘性结扎效率 | 它比钝器结束更有效。 |
摘要 - 钝与粘性结扎
限制内切酶能够dsDNA灭亡and produce DNA fragments with different ends. They recognize specific sequences and restrict DNA creating sticky and blunt ends. Sticky ends have unpaired bases at the end of the fragments. Blunt ends are created due to a straight cleavage and they have base pairs at the ends. Sticky end ligation requires two complementary single-stranded DNA pieces. Blunt end ligation occurs between any two blunt end fragments. This is the difference between blunt and sticky ligation.
References:
1. Roberts,Richard J.“限制酶如何成为分子生物学的主力。”美国国家科学院论文集。国家学院科学网络。2017年4月12日
2。Adnan, Amna. Uses of Restriction Enzymes in Biotechnology. N.p., n.d. Web. 12 Apr. 2017
图片提供:
1。“EcoRV Restriction Site.rsh” By Ramin Herati – Created with Inkscape (Public Domain) via下议院维基梅迪亚
2。“Restriction enzyme Eco RI” By Tinastella – Own work (Public Domain) via下议院维基梅迪亚
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