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Structural View of Biology

Enzymes are Nature's chemists, performing all of the chemical transformations needed for life. Enzymes catalyze chemical reactions by bringing together all of the necessary chemical tools in the proper place. They typically have an "active site" that captures the chemicals that will be modified, holding them in the perfect orientation to perform the chemical change. Researchers have separated the many types of enzymes into a few functional classes, based on the reactions that they perform. Click on any of the sub-categories below to explore a few examples of each enzyme class. You can also explore many other enzymes in the other functional categories in "Structural View of Biology." Click on any of the sub-categories below to explore further.

Oxidoreductases - Shuffling Electrons

Oxidoreductases are experts in oxidation and reduction, where individual electrons are added or removed from molecules during a chemical reaction.

Transferases - Moving Chemical Groups

Transferases are the cell's master builders, taking chemical groups and transferring them from one place to another.

Hydrolases - Breaking Chemical Bonds with Water

Hydrolases break molecules into two pieces by using a molecule of water, which is also broken in half during the reaction.

Lyases - Breaking Chemical Bonds without Water

Lyases break molecules into two pieces, but without using water like the hydrolases.

Isomerases - Changing Molecular Shape

Isomerases shuffle atoms around in a molecule, changing its shape.

Ligases - Making Connections

Ligases connect two molecules, creating a new chemical bond.

Ribozymes - Enzymes Made of RNA

Most enzymes are built of protein, but several RNA enzymes have also been discovered.

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