[Biology Class Notes] on Amino Acids Pdf

The body needs 20  Amino Acids to maintain good health and normal functioning. Nine of these Amino Acids,  the so-called essential Amino Acids, must be ingested through food. Good food Sources are meat, eggs, tofu, soybeans, buckwheat, quinoa, and dairy products.

 

Amino Acids are the building blocks of proteins. When a person eats foods that contain protein, the digestive system breaks down the protein into Amino Acids. The body then combines Amino Acids in different ways to perform physical Functions.  A healthy body can make the other 11 Amino Acids on its own, so it usually does not enter the body through food. Amino Acids help the body create muscle, initiate chemical processes, transport nutrients, and prevent disease, among other things. Amino Acid Deficiency can lead to weakened immunity, digestive problems, depression, childbirth problems, decreased mental alertness, slowed growth in children, and many other health problems. Each essential Amino Acid has a unique function in the organism, and depletion symptoms vary appropriately.

 

Types of Amino Acid

1. Lysine – Lysine plays important role in building muscle, maintaining bone strength, supporting recovery after injury and surgery, and regulating hormones, antibodies, and enzymes. It also has an antiviral effect. 

2. Histidine – Histidine promotes blood cell growth, formation, and tissue repair. It also helps maintain a special protective cover called the myelin sheath that covers nerve cells.

3. Threonine – Threonine is a part of tooth enamel, collagen, and elastin, so it is necessary for healthy skin and teeth. It helps support fat metabolism and can be beneficial to people with indigestion, anxiety, and mild depression.  

4. Methionine – Methionine and the non-essential Amino acid cysteine ​​play a role in skin and hair health and softness. Methionine also helps keep your nails strong. It supports the proper absorption of selenium and zinc and the removal of heavy metals such as lead and mercury.  

5. Valine – Valine is important for mental concentration, muscle coordination, and emotional calm. People can use valine supplements for muscle growth, tissue repair, and energy.

6. Isoleucine – Isoleucine is important for wound healing, immunity, blood sugar control, and hormone production. It is found primarily in muscle tissue and regulates energy levels. 

7. Leucine – Leucine helps regulate blood sugar levels and helps muscle and bone growth and repair. It is also required for wound healing and growth hormone production.

8. Phenylalanine – Phenylalanine helps the body use other Amino acids, proteins, and enzymes. The body converts phenylalanine to tyrosine. This is required for specific brain functions.  Phenylalanine deficiency, although rare, can lead to inadequate weight gain in babies. It can also cause eczema, malaise, and memory loss in adults.  

9. Tryptophan – Tryptophan is required for the proper growth of infants and is a precursor of serotonin and melatonin. Appetite, sleep, emotion, and pain are all regulated by serotonin, a neurotransmitter. Melatonin also regulates sleep.

More on Amino Acids

Amino Acids are the organic compounds which combine to form proteins, hence they are referred to as the building components of proteins. These biomolecules are involved in several biological and chemical functions in a human body and are the necessary ingredients for the growth and development of human beings. There are approximately 300 amino acids which can be found in nature.

Amino acids contain the essential amino groups (-NH₂) and carboxyl groups (-COOH). Amino acids are present in the ingredients of protein. Both peptides and proteins are the long chains of amino acids. Altogether, there are twenty amino acids, which are involved in the construction of proteins.

Listed Below are the Names of Twenty Amino Acids Alongside Their Formula.

General Properties of Amino Acids:

• They have a very high melting and boiling point.

• Amino acids are white crystalline solid substances.

• Amino acids are sweet, tasteless, and bitter in taste

• Most of the amino acids are soluble in water and are insoluble in organic solvents.

Essential and Nonessential Amino Acids

Out of 20 amino acids, our body can easily synthesise a few by their own and are called as non-essential amino acids. They include alanine, asparagine, arginine, amino acid, glutamic acid, cysteine, glutamine, proline, glycine, serine, and tyrosine.

Apart from these, there are other nine amino acids which are very much essential as they cannot be synthesised by our body. They are called essential amino acids and they also include isoleucine, histidine, lysine, leucine, phenylalanine, tryptophan, methionine, threonine, and valine.

Structure 

The general structure of Amino Acids is H2NCH RCOOH and are often written as:

COOH

|

H2N – – C – – H

|

R

There are 20 present amino acids and every one has common structural features – an amino (-NH3+), a carboxylate (-COO-) group and a hydrogen-bonded to an equivalent atom. They differ from each other in their side-chain called R group. Each amino alkanoic acid has 4 different groups attached to α- carbon.

These 4 groups are:

• Amino group

• COOH

• Hydrogen atom

• Sidechain (R)

Sources of Amino Acids 

Amino acids play a vital role in performing several biological and chemical functions in several parts of our body, including building and repairing of the tissues, within the formation and function of enzymes, food digestion, for the transportation of molecules, etc. Our body can synthesise only certain amino acids and therefore the remainder of the amino acids which are called essential amino acids should be supplied through protein-rich foods in our daily diet. Foods rich in amino acids include plant-based products like broccoli, beans, beetroots, pumpkin, cabbage, nuts, dry fruits, chia seeds, oats, peas, carrots, cucumber, green leafy vegetables, onions, soybeans, whole grain, peanuts legumes, lentils, etc. Fruits rich in amino acids are apples, bananas, berries, figs, grapes, melons, oranges, papaya, pineapple, and pomegranates. Other animal products include dairy products, eggs, seafood, chicken, meat, pork etc.

Functions of Amino Acids

Phenylalanine helps in maintaining a healthy systema nervosum and in boosting the memory power.

Valine acts as an important component in promoting muscle growth.

Threonine helps in promoting the functions of the immune system.

Tryptophan is involved in the production of vitamin B3 and serotonin hormone. This serotonin hormone plays a vital role in maintaining our appetite, regulating sleep and boosts our moods.

Isoleucine plays a vital role in the formation of haemoglobin, stimulating the pancreas to synthesise insulin, and in transporting oxygen from the lungs to the various parts.

Methionine is utilised for the treatment of kidney stones, maintaining healthy skin and also useful in controlling invasion of pathogenic bacteria.

Leucine is involved in promoting the protein synthesis and growth hormones.

Lysine is necessary for promoting the formation of antibodies, hormones, enzymes and in the development and fixation of calcium in bones.

Histidine is involved in many enzymatic processes and in the synthesising of both red blood cells (erythrocyte) and white blood cells (leukocytes).

Functions of Non-Essential Amino Acids

Alanine functions by removing toxins from our body and within the production of glucose and other amino acids.

Cysteine acts as an antioxidant provides resistance to our body and inhibits the exhibition of hairs, nails, etc.

Glutamine promotes a healthy brain function and is necessary for the synthesis of nucleic acids – DNA and RNA.

Glycine is useful in maintaining the right cell growth, its function and it also plays a vital role in healing wounds. It acts as a neurotransmitter.

Glutamic acid acts as a neurotransmitter and is mainly involved in the development and functioning of a human brain.

Arginine helps in promoting the synthesis of proteins and hormones, detoxification of the kidneys, in healing wounds, and in maintaining a healthy immune system.

Tyrosine plays a vital role in the production of the thyroid hormones -T3 and T4, in synthesising a class of neurotransmitters and melanin, which is natural pigments found in our eyes, hair, and skin.

Serine helps in promoting muscle growth and in the synthesis of immune system proteins.

Asparagine is mainly involved in the transportation of nitrogen into our body cells, formations of purines and pyrimidine for the synthesis of DNA, in the development of the nervous system and in improving our body stamina.

Aspartic acid plays a serious role in metabolism and in promoting the synthesis of other amino acids.

Proline is mainly involved in the repairing of the tissues in the formation of collagen, preventing the thickening and hardening of the walls of the arteries (arteriosclerosis) and in the regeneration of new skin.

Deficiency of Amino Acids

As mentioned above, amino acids are the building blocks of proteins and proteins play a fundamental role in almost all life processes. Therefore, it is necessary to include all nine essential amino acids in our daily diet to maintain a healthy and proper function of our body. There may be different pathological disorders that may take place due to the deficiency of amino acids some of which are – 

• Edema.

• Anemia.

• Insomnia.

• Diarrhea.

• Depression.

• Hypoglycemia.

• Loss of Appetite.

• Fat deposit in the liver.

• Skin and hair related problems.

• Headache, weakness, irritability, and fatigue.