7 Types of Proteins & Their Function

If you’re into health and wellness, you’ve certainly heard the buzz around protein. Maybe you’ve tried protein powders or meal replacement shakes, or even changed your diet by eating more protein-rich foods.

But protein is not a unique entity. It is a series of diverse and versatile molecules that perform many different functions in the body. Let’s discuss some of the different types of proteins and the important work they do. But first: what are proteins anyway?

What is a protein made of?

Proteins are essential multitaskers in our body and crucial for the structure, function and regulation of all tissues and organs. They are made up of amino acids, with twenty variants determining the unique structure and function of each protein, all of which are encoded by our DNA.

Although usually associated with food intake, proteins also exist within us, which serve as building blocks for various body structures such as muscles and bones. Our body can synthesize some amino acids, but nine essential amino acids must be consumed through our diet.

What do proteins do for your body?

Each type of protein has its own special job. Some proteins help protect us from potentially harmful bacteria, while others ensure that our bodies use vitamins properly.

When we eat protein-rich foods such as meat, fish and eggs, we consume many different types of proteins, and our digestive system breaks them down into amino acids before our body absorbs them. Our bodies then use them for a variety of functions, including everything from muscle movement to metabolism and immunity.

Let’s explore different types of proteins and their respective roles in the body.

Different types of proteins and their functions

Motor proteins

Motor proteins, or contractile proteins, are crucial for proper movement and cell renewal. Think of them as little ‘movers’ in our cells that make sure everything runs smoothly.

These proteins help our muscles move and contract. Without these molecules, our muscles wouldn’t work together properly, our tissues and skin wouldn’t repair themselves properly, and nutrients wouldn’t be delivered properly to our cells.

Myosin is an example of a motor protein. Like a small engine in cells, myosin uses a fuel (a molecule called ATP) to create movement and force, allowing the cell to go where it needs to go.

Transport proteins

As their name suggests, transport proteins transport vital substances throughout the body.

Take breathing for example. We inhale oxygen, which travels to our lungs and must be distributed to crucial organs such as our heart and brain to keep us alive.

The transport protein hemoglobin facilitates this. It contains iron, which allows it to distribute oxygen throughout the body.

Another example is serum albumin, a protein specialized in transporting important molecules such as fatty acids and hormones in the blood.

Defensive proteins

Defensive proteins protect us against potentially harmful pathogens such as viruses and bacteria.

A well-known type of defensive protein is an antibody. The body produces antibodies when it senses danger from invaders to help fight them off.

Defensive proteins also help with blood clotting. When we get a cut, proteins called thrombin and fibrinogen go to work to make our blood sticky and help stop bleeding. So defensive proteins keep us healthy and help our body heal.

Structural proteins

Our bodies are made up of many different parts, and structural proteins are the building materials that hold everything together. They help form bones, muscles, tendons and other important parts of the body.

For example, collagen is a type of structural protein that helps build tendons, which connect muscles to bones. Another protein called keratin helps form and protect our hair, nails and the outer layer of the skin (epidermis).

What is a protein digesting enzyme?

Enzymatic proteins, often simply called enzymes, act as catalysts and accelerate various biochemical processes that are crucial to our well-being. There are more than 2,000 unique species that help us function optimally.

For example, digestive enzymes such as pepsin and amylase support our digestive system, breaking down food into nutrients that our bodies can absorb and use. We get these enzymatic proteins when we eat plant foods like pineapple, papaya, and fermented foods like sauerkraut and kimchi.

Enzymatic proteins are also essential for breathing, muscle and nerve function, and removing toxins from our bodies.

Storage proteins

Storage proteins are like storage boxes in the body. They hold important things we need, such as energy sources and mineral ions (small charged particles of minerals).

A popular example of a storage protein is casein, which many athletes rely on for improved muscle growth. Casein contains nutrients such as amino acids, carbohydrates, phosphorus and calcium.

We consume enough storage proteins when we eat foods such as plant seeds, egg whites and milk.

Is insulin a protein?

Hormonal proteins are essential communicators in our body. They deliver crucial messages between cells, maintaining harmony and balance in our bodily functions, such as metabolism.

Insulin is a well-known hormonal protein. It helps regulate blood sugar levels and plays a crucial role in delivering glucose to cells, especially in key areas such as the liver (which is essential for regulating blood glucose), muscle and fatty tissue.

Without proper insulin activity, glucose builds up in the blood, leading to high blood sugar levels and possibly diabetes. Hormonal proteins ensure seamless cooperation between different parts of the body.

So we have seen that proteins are the multifunctional architects of our body, each fulfilling a unique and vital role. Understanding the diverse jobs of different species can increase our appreciation for the intricate workings of our bodies and the important functions of the foods we eat. So enjoy healthy protein and know that you are supporting your body’s natural healing abilities.

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