Difference Between Denatured and Undenatured Protein

The key difference between denatured and undenatured protein is that denatured proteins are unable to perform its original function, whereas undenatured proteins can perform their functions properly.

Proteins are one of four major components in living organisms, the other three being carbohydrates, fats and minerals. The protein molecule is a large macromolecule consisting of a large number of repeating units that represent the monomers used to make the protein molecule. These monomers are amino acid molecules.

CONTENTS

1. Overview and Key Difference
2. What is a Denatured Protein
3. What is an Undenatured Protein
4. Side by Side Comparison – Denatured vs Undenatured Protein in Tabular Form
5. Summary

What is a Denatured Protein?

Denatured protein molecules are proteins that have lost their proper functioning due to the change in the protein structure. During the process of denaturation, these macromolecules lose their secondary, tertiary or quaternary structures which occur in their native state. This denaturation occurs due to the application of some external stress or a substance. The external stresses include radiation, changes in temperature, change in pH, etc. External substances that can denature a protein include strong acids, strong bases, organic solvents, some salts, etc.

For a protein molecule, the protein folding pattern is the key for its perfect performance. In other words, the proteins must be folded into the right shape in order to function. Hydrogen bonds play an important role in the protein folding process. However, these hydrogen bonds are weak chemical bonds which are easily affected by heat, acidity, varying salt concentrations, etc. Therefore, the presence of these factors can denature a protein.

What is an Undenatured Protein?

Undenatured proteins are the properly functioning proteins which have not undergone any structural deformation. Proteins are made of a large number of amino acids; therefore, these are macromolecules. A linear chain of protein containing a small number of amino acids is named as a polypeptide.

There are four major structural forms of protein: primary structure, secondary structure, tertiary structure and quaternary structure. Most proteins have a folded structure which is a 3D structure. This structure is named as the native structure of the protein, and it is a properly functioning protein, also named as an undenatured protein. Usually, the tertiary structure of proteins and quaternary structure are the most important structures that occur in living organisms.

What is the Difference Between Denatured and Undenatured Protein?

Denatured and undenatured proteins are the two major structural types of protein molecules. The key difference between denatured and undenatured protein is that denatured proteins are unable to perform its original function, whereas undenatured proteins can perform their functions properly. The most common external factors that can cause the denaturation of a protein structure are temperature, radiation, change in pH, presence of strong acids and bases, etc.

Below infographic shows the difference between denatured and undenatured protein in tabular form.

Summary – Denatured vs Undenatured Protein

Denatured and undenatured proteins are the two major structural types of protein molecules. Denaturation of a protein molecule occurs due to several factors such as changes in temperature and pH of the medium in which the protein lies. The key difference between denatured and undenatured protein is that the denatured proteins are unable to perform its original function, whereas the undenatured proteins can perform their functions properly.

Reference:

1. “Denaturation.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., Available here.
2. Szalay, Jessie. “What Is Protein?” LiveScience, Future USA.Inc, 10 Dec. 2015, Available here.

Image Courtesy:

1. “Q10 graphs” By Thomas Shafee – Own work (CC BY 4.0) via Commons Wikimedia
2. “Myoglobin” By →AzaToth – self made based on PDB entry (Public Domain) via Commons Wikimedia