1. What is Enzyme Activity?

Enzyme activity is a measure of the catalytic ability of an enzyme, typically expressed as the amount of substrate converted to product per unit time per milligram of enzyme (U/mg). It's a crucial parameter in enzymology and biochemical research.

2. How Does the Calculator Work?

The calculator uses the enzyme activity equation:

Where:

• \( v \) — Reaction rate (mol/min)
• \( [E] \) — Enzyme concentration (mg)

Explanation: The equation calculates how many units of activity (μmol of substrate converted per minute) are present per milligram of enzyme.

3. Importance of Enzyme Activity Calculation

Details: Measuring enzyme activity is essential for enzyme characterization, purification monitoring, industrial applications, and clinical diagnostics. It helps determine enzyme purity and catalytic efficiency.

4. Using the Calculator

Tips: Enter the reaction rate in mol/min and enzyme concentration in mg. Both values must be positive numbers. The result will be in U/mg (μmol/min/mg).

5. Frequently Asked Questions (FAQ)

Q1: What is one unit of enzyme activity?
A: One unit (U) is defined as the amount of enzyme that converts 1 μmol of substrate to product per minute under standard conditions.

Q2: Why measure enzyme activity per mg?
A: Expressing activity per mg (specific activity) allows comparison between different enzyme preparations regardless of their concentration.

Q3: What factors affect enzyme activity?
A: Temperature, pH, substrate concentration, presence of inhibitors or activators, and enzyme purity all affect measured activity.

Q4: How does this relate to Michaelis-Menten kinetics?
A: The reaction rate (v) used in this calculation is typically the Vmax determined from Michaelis-Menten analysis.

Q5: Can this be used for crude enzyme extracts?
A: Yes, but the result will reflect the total activity in the extract, not the specific activity of the purified enzyme.