Genes: DNA's instructions

Folding: Putting proteins to work

Proteins carry out most of active functions of a cell. From the DNA, we can recognize and read off the amino acids that make up the proteins in our bodies. However, we still only understand a little about how the chain of amino acids becomes a working protein. The three dimensional (3D) structure of a protein (such as the structure of the hormone, insulin, at right) is difficult to predict just from the DNA sequence.

Many proteins are enzymes; these biological catalysts enable or speed up chemical reactions in the cell. Each enzyme has a region into which two or more chemicals fit snugly. This region is called the 'active site'. reactions between components occur through binding first to the active site of the enzyme. Once the reaction occurs, the shapes of the components change so they vacate the active site, leaving the enzyme free to catalyse another reaction.