Enzymes

1. Enzyme Structure

If you remember from earlier lessons, ribosomes are the part of a cell that makes proteins, and proteins can perform various roles in your body. One of those roles is that they can become enzymes.

term to know

Enzyme

A special type of protein that speeds up a chemical reaction by rapidly converting the substrate into the product.

2. Enzyme Function

Enzymes are made up of proteins and speed up chemical reactions in your body. An enzyme can actually make a chemical reaction happen millions of times faster than it would otherwise. This makes them very important to your body.

Enzymes are very specific to the type of reaction in which they participate. Enzymes can join substances together or break them apart.

EXAMPLE

Salivary amylase is an example of one of the enzymes that you have in your body. The purpose of salivary amylase is to break down starches into simple sugars. If you eat something that has a lot of starch in it, the salivary amylase in your saliva will begin to break down those starches into simple sugars in your mouth. This enzyme will not take part in any other reaction in your body; its role is very specific.

However, enzymes can sometimes also join substances together into a larger compound.

3. Enzyme Function Process

Take a look at the diagram above. The gray part represents the enzyme and the green parts represent substrates. A substrate is whatever the enzyme is working on to either join together or break down. The other area is called the active site. The active site is the part of the enzyme where the substrates will attach. These are the three main parts that you'll need to know in relation to an enzyme.

It is important to note that when the substrate attaches to the enzyme, the enzyme will generally mold itself around the substrate; this is called induced fit. That puts pressure on the bonds of the substrate and either bonds those substrates together or helps to break that substrate apart into two separate products.

Again, substrates will attach to an enzyme at the active site. From there, the enzyme will either break those substances down or join them together.

An enzyme, after it participates in this type of reaction, is going to remain unchanged. Therefore, the enzyme can actually be used again. It's going to be the same at the end as it was at the beginning. Conversely, the substrate has changed and become a product; it's different at the end of the process than it was at the beginning.

terms to know

Substrate

The molecule that is acted on by an enzyme.

Active Site

The area on an enzyme where the substrate attaches.

Product

The result of a chemical reaction where an enzyme has acted on a substrate.