The 20 types of proteins and their functions in the body

Proteins are macronutrients basically made up of carbon, hydrogen, oxygen and nitrogen., although some also contain sulfur and phosphorus. These elements studied by biology (and with the sciences related to it) explain a good part of the functioning of our body, both in terms of its movement and, for example, in relation to our mind. However, proteins are present in all kinds of life forms, not just in our species.

Plants synthesize inorganic nitrogen proteins, but animals, unable to carry out this process, have to incorporate these substances through their diet. Proteins are formed by the union of several amino acids, linked by peptide bonds.

As these biomolecules are so important to understand what our body is like, it is useful learn about some of the most common types of protein or relevant to us, and also the amino acids that form them. In this article you will find a brief explanation of these two elements, both amino acids and proteins. Let's start with the first ones.

• You may be interested: "The 4 differences between the animal and plant cells"

What are amino acids

As we have seen, amino acids are the base or raw material of proteins. Basically, they are the raw material from which our entire body is made: muscles, hair, bones, skin and even the brain tissue that produces our thoughts, emotions and consciousness.

Despite the fact that in nature it is possible to find hundreds of amino acids, only 20 are used in the formation of proteins. They are called: protein amino acids.

The 20 types of protein amino acids

Protein amino acids, also called canonical, perform physiological functions on their own, such as glycine or glutamate, which are neurotransmitters. Below you can find the 20 protein neurotransmitters:

• Recommended article: "Types of neurotransmitters: functions and classification"

1. Glutamic acid

This amino acid is considered as the gasoline of the brain And one of its main functions is to absorb excess ammonia in the body.

2. To the girl

The main task of this amino acid is that intervenes in glucose metabolismto.

3. Arginine

It is present in the body's detoxification process, in the urea cycle and in the synthesis of creatinine. In addition, it is involved in the production and release of growth hormone.

4. Asparagine

It is synthesized from aspartic acid, and removes, together with glutamine, excess ammonia from the body and intervenes in the improvement of resistance to fatigue.

5. Cysteine

It is involved in the process of eliminating heavy metals from the body and it is essential in the growth and health of the hair.

6. Phenylalanine

Thanks to this amino acid regulation of endorphins that are responsible for the feeling of well-being is possible. Reduces excess appetite and helps relieve pain.

7. Wisteria

Helps the body in building muscle mass, to the correct healing, prevents infectious diseases and participates in the correct brain function.

8. Glutamine

Glutamine is found abundantly in muscles. This amino acid increases brain function and mental activity and helps solve impotence problems. In addition, it is essential to combat alcohol problems.

9. Histidine

This amino acid is the precursor of histamine. It is found abundantly in hemoglobin and the production of both red blood cells and blood cells is necessary. targets in the blood.In addition, it intervenes in the growth process, in the repair of tissues and the formation of myelin

10. Isoleucine

This amino acid it is part of the genetic code and is necessary for our muscle tissue and the formation of hemoglobin. In addition, it helps regulate blood sugar.

11. Leucine

Like the amino acid above, intervenes in the formation and repair of muscle tissue and collaborates in the healing of the skin and bones. What's more. acts as energy in high-effort workouts and helps increase growth hormone production.

12. Lysine

Along with methionine, synthesizes the amino acid carnitine And it is important in the treatment of herpes.

13. Methionine

It is important to prevent some types of edema, high cholesterol and hair loss.

14. Proline

It is responsible for the synthesis of various brain neurotransmitters related to temporary depression and also collaborates in the synthesis of collagen.

15. Serine

It is an amino acid that participates in the metabolism of fats and it is a precursor of phospholipids that nourish the nervous system.

16. Taurine

Taurine strengthens the heart muscle and prevents cardiac arrhythmias. Improves vision and prevents macular degeneration.

17. Tyrosine

Tyrosine stands out for its function as a neurotransmitter and it can help relieve anxiety or depression.

18. Threonine

Necessary in the detoxification process and participates in the synthesis of collagen and elastin.

19. Tryptophan

Tryptophan is an essential amino acid, that is, the body itself cannot synthesize it and it must be obtained through food. It is a precursor to the neurotransmitter serotonin, associated with the state of mind. Tryptophan is considered a natural antidepressant and also promotes sleep. It is also a very healthy component and easy to find in healthy diets.

• You can learn more about this neurotransmitter in this article: "Tryptophan: characteristics and functions of this amino acid"

20. Valine

Like some of the amino acids above, is important for the growth and repair of muscle tissues. In addition, it also intervenes in the regulation of appetite.

Essential and non-essential amino acids

Amino acids can be classified as essential and non-essential. The difference between these is that the former cannot be produced by the body and, therefore, must be ingested through food. The 9 essential amino acids are:

• Histidine
• Isoleucine
• Leucine
• Lysine
• Methionine
• Phenylalanine
• Threonine
• Tryptophan
• Valine

Not all high-protein foods have the same amount of amino acids. The protein with the highest amino acid content is that of the egg.

Classification of proteins

Proteins can be classified in different ways. Below you can find the different types of protein.

1. According to its origin

One of the best known classifications is according to origin: animal proteins and vegetable proteins.

1.1. Animal proteins

Animal proteins are, as their name suggests, those that come from animals. For example, proteins from eggs or pork.

1.2. Vegetable proteins

Vegetable proteins are those that come from vegetables (legumes, wheat flours, nuts, etc.). For example, proteins from soybeans or peanuts.

2. According to its function

According to its function in our body, proteins can be classified into:

2.1. Hormonal

These proteins are secreted by the endocrine glands. Generally transported through the blood, hormones act as chemical messengers that transmit information from one cell to another.

You can learn more about this type of peptide hormones in our article: "Types of hormones and their functions in the human body”.

2.2. Enzymatic or catalytic

These proteins accelerate metabolic processes in cells, including liver function, digestion or converting glycogen to glucose, etc.

2.3. Structural

Structural proteins, also known as fibrous proteins, are necessary components for our body. They include collagen, keratin, and elastin. Collagen is found in connective, bone and cartilage tissue just like elastin. Keratin is a structural part of hair, nails, teeth, and skin.

2.4. Defensive

These proteins have an immune or antibody function, keeping bacteria at bay. Antibodies form in white blood cells and attack dangerous bacteria, viruses, and other microorganisms.

2.5. Storage

Storage proteins store mineral ions such as potassium or iron. Its function is important, since, for example, the storage of iron is vital to avoid the negative effects of this substance.

2.6. Transport

One of the functions of proteins is transport within our body, because they transport minerals to cells. Hemoglobin, for example, carries oxygen from the tissues to the lungs.

2.7. Receivers

These receptors are usually found outside the cells to control the substances that enter the cells. For example, GABAergic neurons contain different protein receptors on their membranes.

2.8. Contractile

They are also known as motor proteins. These proteins regulate the strength and speed of the heart or muscle contractions. For example, myosin.

3. According to its conformation

Conformation is the three-dimensional orientation that the characteristic groups of the protein molecule acquire in space, by virtue of the freedom they have to rotate.

3.1. Fibrous proteins

They are made up of polypeptide chains aligned in parallel. Collagen and keratin are examples. They have high resistance to cutting and are insoluble in water and saline solutions. They are the structural proteins.

3.2. Globular proteins

Polypeptide chains that coil on themselves, causing a spherical macrostructure. They are usually soluble in water and, in general, are the transporter proteins

4. According to its composition

Depending on their composition, proteins can be:

4.1. Holoproteins or simple proteins

They are made up mainly of amino acids.

4.2. Heteroproteins or conjugated proteins

They are usually composed of a non-amino acid component, and can be:

1. Glycoproteins: structure with sugars
2. Lipoproteins: lipid structure
3. Nucleoproteins: attached to a nucleic acid. For example, chromosomes and ribosomes.
4. Metalloproteins: contain one or more metal ions in their molecule. For example: some enzymes.
5. Hemoproteins or chromoproteins: They have a heme group in their structure. For example: hemoglobin.