Contents

- 1 What does the Michaelis Menten equation tell us?
- 2 Is Michaelis Menten first order?
- 3 How does the Michaelis Menten equation explain why the rate of an enzyme catalyzed reaction is proportional to the amount of enzyme?
- 4 Is Michaelis Menten vs Lineweaver Burk more accurate?
- 5 Why is Michaelis constant important?
- 6 What are the examples of first order reaction?
- 7 What is the difference between zero order removal and first order removal?
- 8 What is a high Km value?
- 9 What is the problem in determining rates at low substrate concentration?
- 10 How do you calculate km?
- 11 What are the steps of enzyme catalysis?
- 12 Why is Hanes Woolf more accurate than Lineweaver-Burk?
- 13 Why are Lineweaver-Burk plots inaccurate?
- 14 Why do we use Lineweaver-Burk plot?

## What does the Michaelis Menten equation tell us?

K_{m} is the Michaelis-Menten constant which shows the concentration of the substrate when the reaction velocity is equal to one half of the maximal velocity for the reaction. It can also be thought of as a measure of how well a substrate complexes with a given enzyme, otherwise known as its binding affinity.

## Is Michaelis Menten first order?

The reaction is first – order kinetics. This means that the rate is equal to the maximum velocity and is independent of the substrate concentration. From the Michaelis Menten Kinetic equation, we have many different ways to find Km and Vmax such as the Lineweaver-Burk plot, Hanes-Woolf plot, and Eadie-Hofstee plot, etc.

## How does the Michaelis Menten equation explain why the rate of an enzyme catalyzed reaction is proportional to the amount of enzyme?

How does the Michaelis – Menten equation explain why the rate of an enzyme – catalyzed reaction is proportional to the amount of enzyme? In the M-M equation above Vmax = k2Eo. In the experiment of Vo vs Eo, So is held constant so all other terms, So, Km, are constant. So Vo = constant Eo or Vo is proportional to Eo.

## 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 V _{max} and more accurate information about inhibition. It increases the precision by linearizing the data.

## Why is Michaelis constant important?

Definition. The Michaelis Constant, K_{M} is very important in determining enzyme-substrate interaction. This value of enzyme range widely and often dependent on environmental conditions such as pH, temperature, and ionic strength.

## What are the examples of first order reaction?

First-order reactions are very common. We have already encountered two examples of first-order reactions: the hydrolysis of aspirin and the reaction of t-butyl bromide with water to give t-butanol. Another reaction that exhibits apparent first-order kinetics is the hydrolysis of the anticancer drug cisplatin.

## What is the difference between zero order removal and first order removal?

In brief: First order elimination kinetics: a constant proportion (eg. a percentage) of drug is eliminated per unit time. First order kinetics is a concentration-dependent process (i.e. the higher the concentration, the faster the clearance), whereas zero order elimination rate is independent of concentration.

## What is a high Km value?

We define Km as the substrate concentration that gives Vmax/2. The higher the Km of an enzyme, the LOWER its affinity for its substrate. This is because a high Km means that it takes a LOT of substrate before the enzyme gets to Vmax/2.

## What is the problem in determining rates at low substrate concentration?

For low substrate concentrations (relative to the Km), depletion of the substrate causes the reaction to slow down more than at higher substrate concentration, so a low enzyme concentration is needed to maintain the initial rate long enough for the initial rate measurement to be made.

## How do you calculate km?

From the graph find the maximum velocity and half it i.e. Vmax/2. Draw a horizontal line from this point till you find the point on the graph that corresponds to it and read off the substrate concentration at that point. This will give the value of Km.

## What are the steps of enzyme catalysis?

Four Steps of Enzyme Action

- The enzyme and the substrate are in the same area. Some situations have more than one substrate molecule that the enzyme will change.
- The enzyme grabs on to the substrate at a special area called the active site.
- A process called catalysis happens.
- The enzyme releases the product.

## Why is Hanes Woolf more accurate than Lineweaver-Burk?

Just like the Lineweaver – Burk equation, the Hanes – Woolf equation is of the form y = mx + c. The Hanes – Woolf plot is thought to be more accurate than Lineweaver – Burk for the determination of kinetic parameters.

## Why are Lineweaver-Burk plots inaccurate?

Enzyme kinetic data that lies closest to the origin on a Lineweaver – Burk plot must have the smallest 1/[S] and 1/V values. Thus relying too heavily on the points far from the origin can lead to inaccurate values of K_{M} and V_{max}.

## Why do we use Lineweaver-Burk plot?

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.