Introduction of Biochemistry, Protein & Amino-Acid

 Introduction of Biochemistry, Protein & Amino-Acid

Introduction of Biochemistry, Protein & Amino-Acid

Introduction of Biochemistry

Biochemistry is the study of chemistry of living organism and deals with the structure and function of tissue cell Organelles and individual bio molecular.

Biochemistry means chemistry of life.

In biochemistry we also study about the chemical process in living organism.

Biochemistry is helpful in the detailed study of structure and function of biomolecules (Carbohydrates, Proteins, Lipids, and Minerals).

Study about the various interaction of different biomolecular (Carbohydrates, Proteins, Lipids, and Minerals).

Study about the energy transformation in living cells organism. The study of natural of enzyme and working of enzymes and study of different types of enzymes.


• Proteins are naturally occurring polymers made up of amino acids.

• Almost everything that occurs in the cells involves one or more Proteins.

• Proteins provide structure, cellular reaction and carried out the tasks.

Role of protein

• Protein perform difference role in the living system.

• Proteins which catalyze by your chemical reactions are called enzymes.

• Proteins are responsible for transportation of metabolites fructose, Glucose or Gases (like Oxygen, Carbon dioxide) are called transport proteins.

• Protein which are responsible for to protect from infection and other toxic substances are called antibiotics or defense proteins.

• Proteins which are required to give strength to cells or tissue are called structural proteins.

• Proteins which are required to carry out mechanical work are called muscle proteins.

Amino acids

20 amino acid are found in protein and they are called standard amino acid. These amino acids contain the carboxyl group and the amino group attached to α carbon.

Classification of protein

1.  Simple Proteins

2.  Conjugated Proteins

3.  Derived Proteins

1.  Simple Proteins:- Simple protein contain only amino acid reduce and other intimately bound material.

2.  Conjugated Proteins: – Conjugated proteins contain in addition to polypeptide chain others substance or groups which impart characteristics properties.

3.  Derived Proteins:- Derived protein are derived from partial to complete hydrolysis from the simple or conjugated proteins by the action of acids, alkalis or enzymes.

Qualitative tests of Proteins:-

1. Heat test:-

• When protein solution is heated in boiling water both the protein get co-angulated and lose their biological activity.

• This is called thermal denaturation of proteins

• e.g. – Boiling water.

2. Test with trichloroacetic acid (TCA)-

• TCA is normally used to precipitate proteins from their solution. TCA denatures the proteins.

3. Biuret Test:-

• Biuret reagents consists of copper sulphate in an alkaline medium when proteins are treated with Biuret reagent it’s shows a violet colour.

4. Hydrolysis Test:-

• Proteins on hydrolysis gives free amino acids Hydrolysis can be carried out by acids like HCL, H2So4, etc. Or Alkalis like – NaOH, KoH etc.

5. Xanthoprotic test:-

• Nitration of aromatic amino acids of protein give yellow colour concentrated nitric acid is used for Nitration.

6. Millon’s Test:-

• Phenolic group of tyrosine of proteins react with mercuric sulphate in the presence of sodium nitrate and sulphuric acid to give red colour.

7. Precipitation test:-

• Protein are Precipitated by using different agents the common precipitation agents are salt, Organic solvent heavy metal ion, acids etc.

• Salt – Ammonium sulphate, Sodium chloride.

• Acids – Trichloroacetic acid (TCA), Acetic acid, Hydrochloric acid.

• Organic solvents – Acetone alcohol

• Heavy metal ions – Ammonium molybdate, Copper or Mercury salts.

Biological value:-

• Proteins give amino acids on hydrolysis during digestion and blood Amino acids are the building blocks required for a cell to sysethesis of proteins.

Biochemical importance of proteins:-

• Proteins are the structural component of protoplasm cell and tissues.

• Enzymes and few hormone are Proteins in nature antibiotics, hemoglobin are also Proteins.

• Protein is one of the important components of diet it is required to maintain growth and healthy functioning of the body.

Protein are also classified and nutritional basic.

1. Complete Proteins: – Proteins which contain all the essential amino acids in required quantity are called complete Proteins.

2.  Incomplete Proteins:- Proteins not containing all the essential amino acid are called incomplete protein.

Protein deficiency:-

• We know that proteins are required for several Vital process in the body.

• Naturally a low intake of proteins in result in deficiency symptoms such condition that are developed may be due to low dietary intake.

Protein deficiency disease:-

A) Kwashiorkor:

• The symptoms of the diseases slow down the growth, edema and change in skin, hair pigmentation and texture.

• Frequently there is liver enlightenment there is vomiting and diarrhea and stools contain much undigested food.

• The course of this disease due to large family size, poor mental health, poor environmental conditions and delayed supplementary feeding.

Note:- This disease appears most commonly in children between the ages of 1 to 4 year.

B) Nutritional edema:

• It result from long contained loss of protein and usually occurs in famine areas. The Proteins deficiency in adults is very rare.

• The deficiency symptoms include loss of weight reduced fat ammonia, infections, frequent loose stools delay in healing of wounds and Edema.

• Use of soybean, milk and eggs and other nutritious diet can cure the Protein deficiency syndrome in adults.

• Deficiency of protein shows different changes in body.

C) Marasmus:

• It is a disease of infants below one year of age.

• It’s cause is Proteins and carbohydrate or other nutritional factor deficiencies.

• Proteins and energy deficiency disease is also known as Marasmus kwashiorkor.

• Marasmus is more likely to occur in poor people.

• The cause of this disease is due to the delayed breast feeding.

• Providing diet rich in colors, proteins and other nutritional factors is the best course in preparation and cure of the Marasmus.

Amino acids

• Amino acids are building blocks of protein.

• Amino acids are compounds that contain and amino group and carboxyl group and the amino group attached to alpha carbon.

• The key elements of an amino acid are Carbon (C) Hydrogen (H) Oxygen (O) and nitrogen (N).

• There are there are 20 amino acids at present in our body in which 9 Essential and 2 Non-essential amino acids.

Essential Amino Acids:-

• The amino acids which cannot be synthesized in the body but are required for normal function of body are called as essential amino acids.

• These amino acids should be supplied through diet.

Non-essential amino acids:-

• The amino acids which are synthesized in the body are called as non-essential amino acids.

Essential Amino Acids

Non-essential amino acids






Aspartic acid




Glutamic acid











A) Physical properties of Amino acids:

1) Solubility:

• All amino acids are Soluble in water but their Solubility various to a great extent.

• Solubility depends on the nature of R- group. i.e. polarity of the amino acid.

• Polar amino acids are highly Soluble in water.

• Non-polar amino acids are highly Soluble in organic solvents like chloroform, ether etc.

2) Optical activity:

• All standard amino acid except glycine have an asymmetric carbon atoms due to this amino
acids are optically active.

3) Acid and Base behaviour:

• Amino acids contain the acidic carboxyl group (-CooH) and the basis group amino (-NH2) Hence amino acids are called as amphoteric molecules or ampholytes (i.e. Amphoteric electrolytes)

B) Chemical properties of Amino acids


• Polypeptides are a chain of amino acids.

• All Proteins are polypeptides.

• 500 or more than 500 amino acids held together by peptide bond.

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