If a protein is denatured what is lostSolutionANS In protein

If a protein is denatured, what is lost?

Solution

ANS:

In protein denaturation “Biological activity” of the protein is lost.

Any disruption of the native conformation leading to loss of biological activity is known as Denaturation.

Protein is functionally active in Tertiary structure. The Tertiary structure of protein is stabilized by weak non- covalent interactions and hydrophobic interactions along with di sulphide bonds.

If any disturbances in the Tertiary structure leading to disruption of stabilizing interactions leads to the loss of biological activity.

Structural organization of protein:

1. Primary Structure: the sequence of amino acids along with the di sulphide bonds.

2. SECONDARY STRUCTURE:

Alfa Helices and Beta- Pleated sheets are most frequently occur in secondary structure in polypeptides. Both of these can case local folding of protein.

The Alfa Helices in polypeptide made up of L- Alfa amino acids are right handed, the Alfa -Helices is stabilized by hydrogen bonds formed between oxygen and amide hydrogen’s of peptide bonds that are a part of linear sequence.

Beta- Pleated sheets: 2 types

A. Parallel: in this the adjacent hydrogen bonding segments are connected by cross over connection [Right handed].

B. Anti-Parallel: In this the adjacent hydrogen bonding segments are connected by HAIRPIN turns or reverse turn [Left Handed].

3. Tertiary structure: It is arisen because of the folding of poly peptides upon itself.

4. Quaternary structure:

Some proteins are made up of 2 or more polypeptides chains, the interaction between different poly peptide are subunits gives rise to the quaternary structure.

DENATURATION OF PROTEIN:

A. Urea:

Urea reacts with the amide bond of protein. The urea molecules are similar to water molecule structure and urea polarity also near to water so the high urea hydrolyzed the peptide bonds of protein.

B. High temperature:

A protein in its native conformation is heated, then it gets denatured and the heat energy disturbs all weak non covalent interactions. Each protein has a characteristic melting temperature are Tm, which is the temperature at which half of native protein can gets disturbed.

C. Detergents:

The enzymes in detergents denatured the protein. It contain amylase, protease and lipase enzymes. Among this protease enzyme degrades the peptide bond and salts of the detergents mostly react with the carboxyl group of protein.

D. Extreme PH:

In isoelectric point proteins had no change. But if the PH is greater than isoelectric point, protein shows negative effect and in lower PH value protein shows positive effect.