Enzymes

Introduction

Living bodies contain concrete elements and enzymes are among them. They are proteins that are found within a cell. They act as a catalyst in the bodies and are the driving force behind numerous chemical reactions required for the existence of life. They help in catalyzing all aspects of cell metabolism specifically. This metabolism may include the digestion of substances in which large nutrient molecules like proteins, fats and carbohydrates are broken down into refined molecules. We also see the concept of conservation and transformation of chemical energy. Some inherited diseases like albinism and phenylketonuria happen due to a lack of enzymes in the human body.

Role of Enzymes in the Digestive System

Have you ever used a vegetable chopper? You could chop the vegetables with a knife and your hands, but it might be difficult and slow. If you use a chopper, you can cut them quickly and precisely. Enzymes are like choppers for our digestive system. They boost the chemical reactions required for our body. As you can use a chopper repeatedly, these enzymes also work continuously in our bodies. But sometimes you need different choppers for different vegetables. Similarly, you need different enzymes performing different functions.

There are various organs of our digestive system that release enzymes. There are five significant organs for this purpose: salivary glands, stomach, pancreas, liver and small intestine. The following are some of the enzymes present in our digestive system-

1. Amylase- Amylase is predominantly produced by the salivary glands, pancreas, and small intestine. A specific amylase, ptyalin, is made by the salivary glands. It breaks down starches into sugars while we eat food.  
2. Pancreatic Amylase- As the name suggests, it is made in the pancreas in secreted into the small intestine. The breakdown of starch molecules into sugars continues here. The sugars are ultimately digested into glucose by other enzymes. Then, it is absorbed into the body through the small intestine walls.
3. Protease- The proteolytic enzymes are produced in the stomach, pancreas and small intestine. Most chemical reactions happen in the stomach and the small intestine. Another enzyme called pepsin is the main enzyme attacking proteins in the stomach. Two more enzymes are under it, and they are trypsin and chymotrypsin. These enzymes are helpful in breaking down the proteins into amino acids.
4. Lipase- It is produced in the two regions namely- the pancreas and the small intestine. During breastfeeding, a particular type of lipase is found in breast milk that helps babies digest fat molecules quickly. They also store energy for the long term and support cellular health.

Restriction Enzymes

The kind of enzyme that recognises a particular use. A short nucleotide sequence that cuts the DNA only at that specific site is called a restriction enzyme. The site where it cuts the DNA is known as the restriction site or the target sequence.

They are found in bacteria and other prokaryotes, where they bind to unique sequences of DNA. Every enzyme recognises just one or a few restriction sites. It forms a double-stranded cut in the DNA molecule when it discovers its target sequence. The cut usually occurs in a very tidy and predictable manner. 

When a restriction enzyme recognises and cuts this site, it always does so in a specific pattern that produces ends with single-stranded DNA “overhangs” and if any other piece of DNA matches them, the overhangs can stick together by complementary base pairing. For the same reason, enzymes that leave single-stranded overhangs produce sticky ends. Sticky ends are helpful in cloning because they keep up two pieces of DNA together so they can be linked by DNA ligase.

All restriction enzymes do not produce sticky ends. Some are “blunt cutters”. They cut straight between a target sequence and leave zero overhangs. Although, blunt-ended fragments are tougher to ligate with each other. This is because there are no single-stranded overhangs to keep up the DNA molecules at their positions.

Factors affecting Enzymes

Enzymes operate best at 37 ℃ or 98 ℉ at the normal body temperature. The temperature can also range from 36.1 ℃ to 37.2 ℃ or 97 ℉ to 99 ℉. 

If the temperature increases too much, it can make the structure of the enzymes break down, affecting their normal functioning. Keeping the body temperature at its optimal range can restore enzyme health.

Health issues like pancreatitis hurt your pancreas as it causes inflammation. This inflammation can lower the effectiveness of various digestive enzymes as the pancreas is one of the major organs responsible for producing digestive enzymes.

A low pH level of the stomach or the intestine is not suitable for the enzymes. It can create an acidic medium that will affect the optimal functioning of the digestive enzymes. A high pH level indicates high alkalinity, which also is not beneficial. In order to not harm the shape and function of the enzymes, a medium, reasonably narrow pH range is considered suitable.

Naturally occurring chemicals called inhibitors may also interfere with an enzyme’s ability to perform a chemical reaction. It is also possible to produce them as medications. Antibiotics are medicines that prevent certain enzymes from aiding bacterial infection to spread.

Diet has a significant role to play whenever it comes to the body. Various foods contain digestive enzymes that support sharing the burden of the naturally occurring enzymes in the human body. For instance, bananas are rich in amylase as well as carbohydrates. If a person eats a banana, the amylase already present helps digest it so that the carbs can be used for energy later.

The body’s overall state of health also has a say in enzyme health. It affects how well the body produces, stores and releases enzymes. Their functionality also depends upon the state of health. This varies from person to person.

Conclusion

There are various organs of our digestive system that release enzymes. There are five significant organs for this purpose: salivary glands, stomach, pancreas, liver and small intestine. Enzymes are proteins that are found within a cell. They are naturally produced through the body but can also be consumed through food and supplements.