Secondary Structure in Proteins

Secondary structure refers to the way small parts of a molecule that are close in proximity to each other fold up to be nearer to one another. Attractive forces within the molecule are responsible for this folding into ordered structures.

You may be familiar with the double helix structure that DNA adopts. A helix is an example of secondary structure. Proteins can adopt a helical structure as well. This structure is called the alpha helix. Attractive forces between the different atoms cause them to want to be next to each other. Another form of secondary structure that is commonly adopted is the beta sheet. Changing even one piece of the primary structure can drastically change the resulting secondary structure of the molecule.

Graphic of a Helix (seen in pink on the left) and a Beta Sheet (seen in yellow on the right).

Hold the arrow from your mouse over the helix or beta sheet and hold down the left mouse button. This will allow you to move and manipulate the structures.

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