2 - Fundamental Methods

Abstract

This chapter discusses the fundamental methods one needs to know to be a molecular biologist. Some of the methods described in the chapter are required almost daily in the practice of molecular biology because it is not the larger concepts but the small things in the daily routine that lead to failure in practice. First, the chapter describes some precipitation techniques of deoxyribonucleic acid (DNA), such as alcohol precipitation. Alternatively, the researcher can desalinate these nucleic acids with commercial concentrators or concentrate them by way of precipitation or with the aid of a Savant Speed Vac (i.e., a vacuum centrifuge). DNA can also be precipitated with polyethylene glycol, although this proves to be interesting only for the purification of larger DNA quantities. In addition to precipitation, the purification of nucleic acids represents another standard procedure of the industrious and successful experimenter. This process is used while working with DNA from material from tissues, bacteria, and gels. There are many different types of DNA and many methods of preparation because the preparation of DNA is one of the chief occupations in this trade and the number of methods and variants is almost endless. A couple of the most useful methods of DNA preparation are presented in this chapter: the preparation of plasmid DNA and the preparation of phage DNA.