The environment of a cell is very complex, making it difficult to study individual reactions, enzymes, or pathways in situ. The traditional approach used by biochemists for the study of these things is to isolate molecules, enzymes, DNAs, RNAs, and other items of interest so they can be analyzed independently of the millions of other processes occurring simultaneously. Today, these approaches are used side by side with newer methods that allow us to understand events inside cells on a larger scale- for example, determining all the genes that are being expressed at a given time in specific cells. In this section we take a brief look at some commonly used methods used to study biological molecules and their interactions.
Thumbnail: A western blot. Image used with permission (CC BY-SA 3.0; Magnus Manske).