157. Match the items in left column with those in the right column :
Conjugated protein Prosthetic group
A. Casein I. Calcium
B. Hemoglobin II. Iron
C. Calmodulin III. Flavin nucleotides
D. Succinate dehydrogenase IV. Heme
E. Ferritin V. Phosphate group
Choose the correct answer from the options given below:
A. A-V, B-IV, C-I, D-III, E-II
B. A-III, B-IV, C-I, D-V, E-II
C. A-V, B-IV, C-II, D-III, E-I
D. A-III, B-IV, C-II, D-V, E-I

Matching Conjugated Proteins with Their Prosthetic Groups

In biochemistry, conjugated proteins are proteins that contain non-polypeptide components, known as prosthetic groups. These prosthetic groups are tightly and often covalently bound to the protein, contributing to its function.

Let’s review the different conjugated proteins and their respective prosthetic groups:

The Options:

Conjugated Protein:

• A. Casein

• B. Hemoglobin

• C. Calmodulin

• D. Succinate dehydrogenase

• E. Ferritin

Prosthetic Group:

• I. Calcium

• II. Iron

• III. Flavin nucleotides

• IV. Heme

• V. Phosphate group

The Correct Answer:

D. A-III, B-IV, C-II, D-V, E-I

Explanation:

1. A. Casein: The prosthetic group for casein is the phosphate group (V). Casein proteins are phosphoproteins, and their phosphate groups play a role in their structure and function in milk.

2. B. Hemoglobin: Hemoglobin contains the heme group (IV), which is crucial for oxygen binding. The heme group contains an iron (II) ion that allows hemoglobin to bind to oxygen.

3. C. Calmodulin: Calmodulin is a protein that binds to calcium ions (I), which induces a conformational change and allows calmodulin to regulate various enzymes.

4. D. Succinate dehydrogenase: The prosthetic group for succinate dehydrogenase is flavin nucleotides (III), which are involved in the electron transfer reactions of the enzyme.

5. E. Ferritin: Ferritin is a protein that stores iron (II) ions (II). Iron is the prosthetic group involved in its iron storage function.

Conclusion

Understanding conjugated proteins and their prosthetic groups is essential for comprehending their functions in biological systems. These non-polypeptide components, such as heme, phosphate groups, and flavin nucleotides, are integral to the biochemical properties and functionality of various proteins like hemoglobin, casein, and succinate dehydrogenase.