In basic enzyme kinetics reaction, the value of Km is 0.6 mM and the v...
V
max of an enzyme reaction is double of the velocity when [S] = K
mSo velocity was 20 mMs
-1 when [S] =K
mTherefore v
max for the given reaction is
20 x 2 = 40 mMs
-1
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In basic enzyme kinetics reaction, the value of Km is 0.6 mM and the v...
Enzyme Kinetics
In enzyme kinetics, the study of enzyme-catalyzed reactions, two important parameters are the Michaelis-Menten constant (Km) and the maximum velocity (Vmax) of the reaction. The Michaelis-Menten equation describes the relationship between the rate of a reaction and the substrate concentration.
Michaelis-Menten Equation:
The Michaelis-Menten equation is given by:
V = (Vmax * [S]) / (Km + [S])
where:
V = velocity of the reaction
[S] = substrate concentration
Vmax = maximum velocity of the reaction
Km = Michaelis-Menten constant
Km and Vmax:
Km represents the substrate concentration at which the reaction velocity is half of the maximum velocity. It is a measure of the affinity of the enzyme for its substrate. A lower Km value indicates a higher affinity of the enzyme for the substrate.
Vmax represents the maximum velocity that can be achieved by the enzyme-catalyzed reaction. It indicates the rate of reaction when the enzyme is saturated with substrate.
Given Information:
Km = 0.6 mM
Velocity (V) = 20 mM/s (at the time point when [S] = Km)
Determining Vmax:
We can use the Michaelis-Menten equation to determine Vmax using the given information.
At the time point when [S] = Km, the velocity of the reaction (V) is equal to Vmax/2. Therefore, we can write:
Vmax/2 = (Vmax * Km) / (Km + Km)
Simplifying this equation, we get:
Vmax/2 = (Vmax * Km) / (2Km)
Cross-multiplying and simplifying further, we get:
2Vmax * Km = Vmax * Km
Cancelling out Vmax and Km, we get:
2 = 1
This equation is not possible mathematically, which means our assumption that Vmax/2 = Vmax * Km / (Km + Km) is incorrect.
Correcting the Assumption:
We need to correct our assumption by considering that the velocity at the time point when [S] = Km is not exactly equal to Vmax/2. Instead, it is closer to Vmax/2.
To find the value of Vmax, we need more information about the velocity at different substrate concentrations or the initial rate of the reaction.
Therefore, we cannot determine the exact value of Vmax based on the given information.