What Is Protein And Its Function : All About Proteins - Part 1.

Updated: Aug 15, 2021

If we consider the human body composition then Protein is the second most abundant compound of our body, first being the water. Owing to this we can clearly make out the importance of protein for our body.

Now let see what actually is a protein,

If we look closely than protein is nothing but a chain of amino acids linked together with a peptide bond.

And depending upon the length of chain and how they are bonded we can see four structures of protein :

1. Primary

2. Secondary

3. Tertiary

4. Quaternary

> Primary – The primary structure of a protein is the linear polypeptide chain formed by the amino acids in a particular sequence. Changing the position of even a single amino acid will result in a different chain and hence a different protein.

> Secondary – The secondary structure of a protein is formed by hydrogen bonding in the polypeptide chain. These bonds cause the chain to fold and coil in two different conformations known as the α-helix or β-pleated sheets. The α-helix is like a single spiral and is formed by hydrogen bonding between every fourth amino acid. The β-pleated sheet is formed by hydrogen bonding between two or more adjacent polypeptide chains.

> Tertiary – The tertiary structure is the final 3-dimensional shape acquired by the polypeptide chains under the attractive and repulsive forces of the different R-groups of each amino acid. This is a coiled structure that is very necessary for protein functions.

> Quaternary – This structure is exhibited only by those proteins which have multiple polypeptide chains combined to form a large complex. The individual chains are then called subunits.

Now lets see what is an amino acids,

Amino acid consists of,

NH2 : Amine group

COOH : Carboxylic acid group

CHR : Central carbon atom with unique side chain.

These amine group and carboxylic acid group gives us the name amino acid.

Now based on the side link (R) there are different amino acids present in the nature but our body requires only 20 amino acids to prepare all the proteins needed for optimal human functioning and based upon our body's ability to produce them, they are categorized into three categories :

Essential Amino Acids : 9 Amino acids which our body cant produce and its necessary to consume them from our diet.
Non Essential Amino Acids : 7 Amino acids which our body can produce using other amino acids and other substances and its not necessary to get these from diet on a daily basis.

3. Conditionally Essential Amino Acids : 4 amino acids which our body can produce but in certain conditions such as stress, endurance activities, high intensity workouts we might need to consume it through our food.

Those foods which have all the essential amino acids in sufficient quantity is termed as a source of complete proteins.

Now we know about proteins, lets look into their functions :

1. Repair & Maintenance

These proteins are called as the structural proteins which help in providing the structure to our muscles, bones, hair, skin , nails etc. and thus plays a vital role when we want to build muscles.

2. Production of Hormones

These proteins are called as the messenger protein since they help us to produce hormones thus helping different organs to interact with themselves.

eg. Insulin, Secretin etc.

3. Production of Enzymes

These proteins are called as the enzymatic proteins which acts as a catalyst to speed up all the chemical reactions is our body such as digestion of carbs, fats and protein and the synthesis of DNA etc.

4. Transport and Storages of Molecules

Haemoglobin which helps in transporting oxygen throughout our body via blood is made out of protein, and even the ferritin and calbindin which helps in the transport and storage of iron and calcium respectively is made out of protein.

If you dont know how to breathe during exercise check this video : BREATHING WHILE EXERCISING

5. Production Of Antibodies

Antibodies which provides us with the immunity against antigens such as bacteria and viruses are made out of protein, this explains the role of protein in building our immunity

6. Energy Production

If we overconsume Protein( more than our structural and functional demands) than these protein can be converted into glucose and used as energy or it can be converted into fat and stored as energy.

7. Aids in Fat Loss

Just eating protein wont help you lose fat but it has few properties which helps us to be in a calorie deficit and start losing fat.

a. High thermic effect of food ( burns more calories in the digestion and absorption of the food)

b. Reduces the ghrelin response which is the hunger hormone in our body.

c. Is more satiating than carbs and fat thus keeping us fill for long and reducing our overall calorie intake.

d. Helps in building muscles which indirectly increasing our metabolizing thus increasing our calorie expenditure.

To know more about fat loss check this video : FAT LOSS SCIENCE

Reading all these you can easily make out that protein is not just for the bodybuilders but it is for everyone who has a body and want to function optimally,

Protein is an essential macronutrient which means that without consuming the essential amino acids we cant survive.

To know more about protein make sure you watch this video :