DNA Extraction from Bacterial Cultures

Abstract

There are several different protocols available for the extraction of DNA from bacteria. These have been developed over the past 30 years, starting with the first and best-known method described in the early 1960s by Marmur (1961). Of course, the choice of a particular method ultimately depends on the bacterial species from which the DNA must be extracted. However there are a few recent protocols, including the following one, that are suitable for use with almost any species, at least any gram-negative bacteria. Gram-positive bacteria, because of their thick cell wall, usually require more severe treatments during the first steps of the extraction, i.e., those that are devoted to lysis of the cells. Recently, many kits for the extraction of DNA from biological samples have become commercially available. These procedures are usually very simple, fast, and inexpensive; however they are mostly designed for extraction of DNA from tissues or body fluids of higher organisms and can fail with bacterial cultures.