From Structure to Function

There are many levels of protein function, ranging from atomic reorganizations to changes in the development of an organism, but all of them involve binding to other molecules, large and small. Sometimes this specific molecular recognition is the sole biochemical function of a protein, but in other cases the protein also promotes a chemical transformation in the molecule that it binds. This chapter looks first at how the structural features described in Chapter 1 dictate the ability of proteins to recognize specifically and bind a wide variety of ligands. The second part of the chapter looks at how these structural features dictate the ability of proteins to catalyze the wide variety of chemical transformations on which life depends. 2