What is the Lineweaver-Burk equation?
The Lineweaver-Burk equation is a linear equation, where 1/V is a linear function of 1/[S] instead of V being a rational function of [S]. The Lineweaver-Burk equation can be readily represented graphically to determine the values of Km and Vmax.
What is Vmax equation?
Vmax is equal to the product of the catalyst rate constant (kcat) and the concentration of the enzyme. The Michaelis-Menten equation can then be rewritten as V= Kcat [Enzyme] [S] / (Km + [S]). Kcat is equal to K2, and it measures the number of substrate molecules “turned over” by enzyme per second.
What is the importance of Lineweaver-Burk equation?
Uses of Lineweaver–Burk Plot Used to determine important terms in enzyme kinetics, such as Kmand Vmax, before the wide availability of powerful computers and non-linear regression software. Gives a quick, visual impression of the different forms of enzyme inhibition.
What is plotted on a Lineweaver-Burk plot?
For a Lineweaver-Burk, the manipulation is using the reciprocal of the values of both the velocity and the substrate concentration. The inverted values are then plotted on a graph as 1/V vs. 1/[S].
What is a Lineweaver-Burk plot used for?
The Lineweaver–Burk plot was widely used to determine important terms in enzyme kinetics, such as Km and Vmax, before the wide availability of powerful computers and non-linear regression software. The y-intercept of such a graph is equivalent to the inverse of Vmax; the x-intercept of the graph represents −1/Km.
Why is the Lineweaver-Burk useful?
While the Lineweaver-Burk is useful for determining important variables in enzyme kinetics, it is prone to error. The y-axis of the plot takes the reciprocal of the rate of reaction, meaning small errors in measurement are more noticeable.
Is Michaelis Menten vs Lineweaver Burk more accurate?
For instance; Lineweaver-Burke plot, the most favoured plot by researchers, has two distinct advantages over the Michaelis-Menten plot, in that it gives a more accurate estimate of Vmax and more accurate information about inhibition. It increases the precision by linearizing the data.
How do you find Vmax?
Ease of Calculating the Vmax in Lineweaver-Burk Plot Next, you will obtain the rate of enzyme activity as 1/Vo = Km/Vmax (1/[S]) + 1/Vmax, where Vo is the initial rate, Km is the dissociation constant between the substrate and the enzyme, Vmax is the maximum rate, and S is the concentration of the substrate.
How do you get Vmax?
This is usually expressed as the Km (Michaelis constant) of the enzyme, an inverse measure of affinity. For practical purposes, Km is the concentration of substrate which permits the enzyme to achieve half Vmax….plotting v against v / [S] gives a straight line:
- y intercept = Vmax.
- gradient = -Km.
- x intercept = Vmax / Km.