Ethanol precipitation of DNA and RNA

목차

1. Introduction
2. Materials
3. Protocol
4. Precipitation of RNA with ethanol
5. References

본문내용

1. Introduction

- Precipitation with ethanol is the standard method to recover nucleic acids from aqueous solutions.
- Rapid, virtually foolproof, and efficient.

1-1. Principle
Ethanol depletes the hydration shell from nucleic acids and exposes negatively charged phosphate groups. counterions such as Na⁺ bind to the charged groups and reduce the repulsive forces between the polynucleotide chains to the point where a precipitate can form. Ethanol precipitation can therefore only occur if cations are available in sufficient quantity to neutralize the charge on the exposed phosphate residues.

1-2. Cations

1) Ammonium acetate
․ reduces the coprecipitation of unwanted contaminants (dNTPs or oligosaccharides).
․ reduces the possibility of coprecipitation of oligosaccharide digestion products.
․ should not be used when the precipitated nucleic acid is to be phosphorylated, since bacteriophage T4 polynucleotide kinase is inhibited by ammonium ions.

참고 자료

Molecular cloning : a laboratory mannual 3rd ed. Sambrook and Russell. A8.12-A8.16
http://apollo.mokpo.ac.kr/~sjkim/cgi-bin/technote
http://biochemistry.yonsei.ac.kr/biochem_molecular/gene_cloning_20.php
http://home.knue.ac.kr/~biomodule/module/module06_t.hwp