1. What is Enzyme Specific Activity?

Specific Activity (SA) is a measure of enzyme purity and activity, defined as the number of enzyme units per milligram of total protein. It's a key parameter in enzyme characterization and purification.

2. How Does the Calculator Work?

The calculator uses the specific activity formula:

Where:

• \( SA \) — Specific activity (U/mg)
• \( Activity \) — Enzyme activity (U/mL)
• \( Protein\ Concentration \) — Total protein concentration (mg/mL)

Explanation: The formula calculates how many units of enzyme activity are present per milligram of total protein in the sample.

3. Importance of Specific Activity

Details: Specific activity is crucial for assessing enzyme purity during purification processes, comparing different enzyme preparations, and determining the catalytic efficiency of enzymes.

4. Using the Calculator

Tips: Enter enzyme activity in U/mL and protein concentration in mg/mL. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a unit of enzyme activity?
A: One unit (U) is typically defined as the amount of enzyme that catalyzes the conversion of 1 μmol of substrate per minute under specified conditions.

Q2: How does specific activity change during purification?
A: Specific activity increases as the enzyme is purified, reaching a maximum when the enzyme is pure.

Q3: What are typical specific activity values?
A: Values vary widely between enzymes. Pure enzymes might have specific activities ranging from 1 to over 1000 U/mg depending on the enzyme.

Q4: Why measure specific activity?
A: It helps track purification efficiency, compare different enzyme preparations, and determine enzyme purity.

Q5: Can specific activity be used to calculate enzyme concentration?
A: Yes, if you know the specific activity of the pure enzyme, you can estimate the enzyme concentration in a sample.