Enzymes: What is a Biological Catalyst?
Enzymes are molecules of protein that are found in the cells of a body, and they are responsible for speeding up all the bodily processes that take place at every moment. We know that catalysts while conducting experiments, are the chemicals we use to increase the rate of chemical reactions. Similarly, enzymes are organic catalysts which help our bodies increase the rate of processes which take place in the body. Enzymes are organic catalysts that are present in every single living organism. To answer the question of what is a biological catalyst, it is enzymes that help break down our bodily systems and help them function appropriately.
Some examples of enzymes are:
Maltase - These break down sugar maltose found in fatty foods like potatoes and pasta, into glucose.
Lactase - These break down lactose available in the sugar present in milk into glucose and galactose.
Lipases - These help to digest food by breaking down fats in the stomach.
Characteristics of Enzyme Catalysts
Enzymes are organic catalysts which are very important for the functioning of living beings. Here are some of the characteristics of enzyme catalysts that you should know.
Specificity: An enzyme cannot be used for just anything; each enzyme serves its own specific purpose. An enzyme changes form to accommodate the bodily process it is going to catalyze.
Stability: Enzymes do not change during a reaction, they remain the same and go on to form and reform covalent bonds to get their work as an organic catalyst done.
Small: A single enzyme can catalyze 1 to 10,000 molecules per second, thus, generally only a small amount of enzymes is needed for a catalysis process to be carried out efficiently.
Controllable: Enzymes are organic catalysts that are easy to control in a variety of ways. Cofactors and coenzymes come into play here to together perform the function of catalysis via the enzyme. Enzymes can be controlled through the following:
Temperature: Enzyme shape changes along with the temperature.
PH Level: The acidity of an active site can change the shape of the enzyme.
Enzyme Activators: Enzyme activators are of various kinds and they help start the process of catalysis by enzymes.
Inhibitors: These produce the opposite effect of activators for enzymes. Something like snake venom is a good example of an inhibitor.
Enzymes are organic catalysts and the process of the function that they serve is called enzyme catalysis. Enzyme catalysis occurs at a local site in the body, which is called the ‘active site’ of the catalyst reaction of the enzyme. Let’s learn a little more about the process of enzyme catalysis.
The reaction upon which enzymes have to work to catalyse are called substrates. The job of the enzyme is to either break down a substrate or form more of the same substrate, and it does this through the process of enzyme catalysis.
Process of Enzyme Catalysis
The enzyme first attracts a substrate to the active site > the enzyme latches on to the substrate, and creates what we call an enzyme-substrate complex > catalysis takes place and forms the enzyme-products complex > the enzyme lets the substrate go and moves on to the next substrate to carry out catalysis.
[Image will be Uploaded Soon]
In the image, two substrates are attracted to an enzyme. Once these two substrates of different shapes and sizes latch on to the enzyme, they come out together as a product - this has been the process of explaining how enzymes are organic catalysts.
Thus, the enzyme arrives at the active site while the substrate is still a substrate (enzyme-substrate complex) and when the enzyme leaves, it leaves the substrate as a product.
You must be wondering how enzymes can just come, do their work and leave - there has to be some more to it than that, right?
You are absolutely right !
As mentioned before, enzyme activators help start the process of catalysis in the body. They cling on the body of the enzyme molecule and nudge the enzyme on to do its job faster.
Examples of Enzyme Activators
Bodily activators for enzymes:
A. Hexokinase-I (HK-I)
This enzyme activator helps in the process of glycolysis by attracting glucose and speeding up the process of what is a biological catalyst.
B. Glucokinase-I (GK)
This enzyme activator is similar to HK-I in that it incites the same process of catalysis. This means that GK also attracts the breakdown of glucose, but through a different biological pathway.
C. Substrates also Sometimes Act as Activators by Clinging on the Enzyme.
An alternative example of activators for enzymes is an enzyme inducer. Enzyme inducers are particular drugs that people can take to either activate an enzyme, or to make the bodily system which activates the enzyme better.