For more information, log on to-
http://shomusbiology.weebly.com/
Download the study materials here-
http://shomusbiology.weebly.com/bio-m...
DNA isolation is a routine procedure to collect DNA for subsequent molecular or forensic analysis. There are three basic and two optional steps in a DNA extraction: Breaking the cells open, commonly referred to as cell disruption or cell lysis, to expose the DNA within. This is commonly achieved by chemical and physical methods-blending, grinding or sonicating the sample. Removing membrane lipids by adding a detergent or surfactants. Removing proteins by adding a protease (optional but almost always done). Removing RNA by adding an RNase (often done). Precipitating the DNA with an alcohol — usually ice-cold ethanol or isopropanol. Since DNA is insoluble in these alcohols, it will aggregate together, giving a pellet upon centrifugation. This step also removes alcohol-soluble salt. See ethanol precipitation.
Refinements of the technique include adding a chelating agent to sequester divalent cations such as Mg2+ and Ca2+, which prevents enzymes like DNase from degrading the DNA.
Cellular and histone proteins bound to the DNA can be removed either by adding a protease or by having precipitated the proteins with sodium or ammonium acetate, or extracted them with a phenol-chloroform mixture prior to the DNA-precipitation. Source of the article published in description is Wikipedia. I am sharing their material. © by original content developers of Wikipedia.
Link- http://en.wikipedia.org/wiki/Main_Page Animation source: University of Nebraska. Copyright 2000. All the credit goes to the original content developer.
Link: http://passel.unl.edu/communities/ind...
DNA extraction from plants plant breeding and biotechnology | |
| 558 Likes | 558 Dislikes |
| 84,658 views views | 750K followers |
| Education | Upload TimePublished on 17 Mar 2013 |
Không có nhận xét nào:
Đăng nhận xét