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Michaelis Constant given Catalytic Rate Constant and Initial Enzyme Concentration Calculator

Michaelis Constant Formula:

\[ K_M = \frac{S \times ((k_{cat} \times [E_0]) - V_0)}{V_0} \]

mol/m³
s⁻¹
mol/m³
mol/m³·s

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1. What is Michaelis Constant?

Definition: The Michaelis Constant (KM) is numerically equal to the substrate concentration at which the reaction rate is half of the maximum rate of the system.

Purpose: It's a key parameter in enzyme kinetics that indicates the enzyme's affinity for its substrate.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ K_M = \frac{S \times ((k_{cat} \times [E_0]) - V_0)}{V_0} \]

Where:

Explanation: The formula calculates KM based on the relationship between substrate concentration, enzyme concentration, catalytic rate, and initial reaction rate.

3. Importance of Michaelis Constant

Details: KM is crucial for understanding enzyme kinetics, determining enzyme efficiency, and comparing different enzymes or substrates.

4. Using the Calculator

Tips: Enter all required values in appropriate units. All values must be positive numbers. Typical ranges:

5. Frequently Asked Questions (FAQ)

Q1: What does a low KM value indicate?
A: A low KM indicates high enzyme affinity for the substrate, meaning the enzyme reaches half its maximum velocity at low substrate concentrations.

Q2: How is KM related to Vmax?
A: KM is the substrate concentration at which reaction rate is half of Vmax.

Q3: What factors affect KM?
A: Temperature, pH, enzyme and substrate types, and presence of inhibitors or activators.

Q4: Can KM be negative?
A: No, KM is always positive as it represents a concentration.

Q5: How is KM determined experimentally?
A: Typically through Lineweaver-Burk plots or other kinetic studies measuring reaction rates at various substrate concentrations.

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