Making Protein Machinery

You can't see proteins, so how do you study them?

If you can't see it with the naked eye, you have to find ways to make it visible. First, many cell proteins are not visible to the eye because they are dissolved in the water that is inside and outside of cells. You can often see these proteins if you change them so they no longer dissolve in water. One way to make a protein dissolvable is to change its structure (called denature) so that it precipitates out of solution.

Heat denatures egg-white protein and makes it more visible

Cells are made up of more than just proteins. So how do you separate the proteins to study them?

Cells contain mixtures of proteins and a large number of other chemicals. You need to have a way to separate proteins from all the other stuff inside of cells. Lipid and salts are the main chemicals that need to be removed in order to study pure proteins. After removing lipid and salts, the different kinds of proteins have to be separated from one another.

There are six basic steps needed to identify different kinds of proteins. In order, these are: (please follow links below)

1.) Centrifuge

2.) Get the lipids out

3.) Get the salts out

4.) Separate and purify

5.) Determine the amino acid sequence

6.) Determine the 3D structure.