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Substrate Concentration given Catalytic Rate Constant and Dissociation Rate Constants Calculator

Substrate Concentration Formula:

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

mol/m³
mol/m³·s
s⁻¹
mol/m³
mol/m³

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1. What is Substrate Concentration?

Definition: Substrate concentration is the number of moles of substrate per liter solution in an enzyme-catalyzed reaction.

Purpose: This calculator helps determine the substrate concentration needed for a given initial reaction rate in enzyme kinetics.

2. How Does the Calculator Work?

The calculator uses the formula:

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

Where:

Explanation: The formula calculates substrate concentration based on enzyme kinetics parameters.

3. Importance of Substrate Concentration

Details: Proper substrate concentration is crucial for enzyme activity studies, drug development, and biochemical research.

4. Using the Calculator

Tips: Enter all required parameters. Ensure denominator (kcat×[E0] - V0) is positive.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range for KD?
A: KD values vary widely but often range from 10⁻⁶ to 10⁻³ mol/m³ for enzyme-substrate complexes.

Q2: How do I measure initial reaction rate V0?
A: V0 is typically measured experimentally as the slope of product concentration vs time at t=0.

Q3: What if my calculation gives a negative value?
A: This means (kcat×[E0]) ≤ V0, which is physically impossible. Check your input values.

Q4: What units should I use?
A: Consistent units are required (mol/m³ for concentrations, s⁻¹ for rate constants).

Q5: Can I use molar (M) instead of mol/m³?
A: Yes, but convert all concentrations (1 M = 1000 mol/m³).

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