Given below are two statements:
Statement (I) : Specific activity of an enzyme is the number of an enzyme units in each milligram of protein.
Statement (II) : Specific activity of an enzyme is maximum and on further purification of that protein does not change the specific activity in the condition when enzyme is pure.
In light of the above statements, choose the most appropriate answer from the options given below.
Show Hint
Specific activity serves as the standard measure of enzyme purity.
An increase in specific activity across purification steps indicates successful purification, which plateaus when the enzyme is $100\%$ pure.
Both Statement (I) and Statement (II) are correct.
Statement (I) and Statement (II) are incorrect.
Statement (I) is correct but Statement (II) is incorrect.
Statement (I) is incorrect but Statement (II) is correct.
Show Solution
Verified By Collegedunia
The Correct Option isA
Solution and Explanation
Step 1: Understanding the Concept:
Specific activity is a key parameter used to assess the purity of an enzyme preparation.
It relates the total catalytic activity of the enzyme to the total amount of protein present in the mixture. Detailed Explanation:
- Evaluating Statement (I): Specific activity is defined as the units of enzyme activity per milligram of total protein present ($\text{units/mg}$).
One unit of enzyme activity is typically defined as the amount of enzyme that catalyzes the conversion of 1 micro-mole of substrate per minute under defined assay conditions. Thus, Statement (I) is correct.
- Evaluating Statement (II): During a protein purification process, unwanted non-enzymatic proteins are systematically removed.
As a result, the total amount of protein (the denominator) decreases while the total enzyme activity (the numerator) remains relatively high, causing the specific activity ($\text{units/mg}$) to increase.
Once the enzyme is completely pure, all contaminating proteins have been removed.
At this point, any further purification steps cannot increase the proportion of the enzyme in the sample.
The specific activity reaches a maximum constant value and does not change. Thus, Statement (II) is correct. Step 2: Final Answer:
Both Statement (I) and Statement (II) are correct, corresponding to option (A).
