Lock & Key Theory

Keywords

Lock & Key, enzymes, reactions, substrate, denatured.

Introduction

The lock and key theory of how an ezyme reacts with proteins in your digestive system is how we get glucose and fructose from the foods we eat. The proteins form together with an enzyme to create an enzyme-substrate complex.

The Basics

So, lock and key. What would you do with an actual lock and key? You have a lock on your door, and to open it, you have to insert a key to open it. But, how does your door know what key is the correct one? It is formed in a combination to be set a certain way, so that only one key can fit the door and be opened.

Interesting fact: there are over 1,500 enzymes that have been identified as a result of constant research. Some have even had their structure shown through x-ray crystallography, which was made famous by Rosalind Franklin.

This is the same as the theory about enzymes. An enzyme has a combination like the lock of the door. When a protein is sought out to break up, it has to be the same combination in order for it to attach and be broken down into sugars.

The Three Molecules

There are three molecules that are broken down by enzymes:

• Carbohydrates: these are molecules that are found in living organisms, and are made up of carbon, hydrogen and oxygen atoms.
• Proteins: a combination of amino acids, a protein is needed for the progressive growth of muscles. An enzyme itself is a protein, but they also break down other proteins.
• Lipids: a diverse group of organic compounds that consist of fats, oils, hormones and membranes that do not function well with water.

Denatured Enzyme

An enzyme has to work within a certain range of temperature and pH balance. If the enzyme ends up being exposed to temperature or pH levels outside of this range, it can become denatured, which means that it will stop working and not break anything down.