1. What is Substrate Concentration Calculator?

Definition: This calculator determines the initial substrate concentration using Michaelis-Menten kinetics parameters.

Purpose: It helps biochemists and enzymologists estimate substrate concentration when other kinetic parameters are known.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( S_o \) — Initial substrate concentration (mol/m³)
• \( K_M \) — Michaelis constant (mol/m³)
• \( V_0 \) — Initial reaction rate (mol/m³·s)
• \( k_{cat} \) — Catalytic rate constant (s⁻¹)
• \( [E_0] \) — Initial enzyme concentration (mol/m³)

Explanation: The formula rearranges the Michaelis-Menten equation to solve for substrate concentration.

3. Importance of Substrate Concentration

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

4. Using the Calculator

Tips: Enter all parameters in appropriate units. Ensure \( (k_{cat} \times [E_0]) > V_0 \) for valid results.

5. Frequently Asked Questions (FAQ)

Q1: What is the Michaelis constant (K_M)?
A: It's the substrate concentration at which the reaction rate is half of V_max.

Q2: How is initial reaction rate (V₀) measured?
A: Typically by monitoring product formation or substrate disappearance in early reaction stages.

Q3: What does k_cat represent?
A: The turnover number - maximum number of substrate molecules converted to product per enzyme active site per second.

Q4: When is this calculation most useful?
A: When designing experiments or analyzing enzyme kinetics data where substrate concentration needs to be determined.

Q5: What if I get a negative result?
A: Check your inputs - this suggests \( V_0 > k_{cat} \times [E_0] \), which isn't physically possible.