# What are enzyme reactions?

## What are enzyme reactions?

Enzyme Kinetics: Basic Enzyme Reactions Enzymes are catalysts and increase the speed of a chemical reaction without themselves undergoing any permanent chemical change. where E represents the enzyme catalyzing the reaction, S the substrate, the substance being changed, and P the product of the reaction.

## What is order of enzymatic reaction?

Enzyme Concentration

first rate = k[S] rate is proportional to the first power of substrate concentration
second rate = k[S][S]=k[S]2 rate is proportional to the square of the substrate concentration
second rate = k[S1][S2] rate is proportional to the first power of each of two reactants

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 Km and Vmax?

Vmax is the maximum rate of an enzyme catalysed reaction i.e. when the enzyme is saturated by the substrate. Km is measure of how easily the enzyme can be saturated by the substrate. Km and Vmax are constant for a given temperature and pH and are used to characterise enzymes.

### How do you calculate the rate of enzyme reaction?

With these factors constant, the only factor left affecting the rate is the amount of substance used or product formed. Thus, the rate of a reaction can be calculated by multiplying the rate constant by the substrate concentration (amount) or by determining reaction velocity (V).

Are all proteins enzymes?

Protein also helps in growth of a living being. Enzymes are biological catalysts that speed up biochemical reactions inside a living organism. Enzymes have an active site where the reacting molecule binds to, which helps in speeding up the reaction.

#### How do you calculate total enzyme concentration?

The enzyme concentration in the reaction is 10 µg/ml = 10 mg/L = 0.01 g/L. The enzyme has a molecular mass of 50,000 g/mole, so we calculate the enzyme concentration to be (0.01 g/L) / (50,000 g/mole) = 2 x 10-7 mol/L = 0.2 µmoles/L.

#### How do you calculate the rate of an enzymatic reaction?

What is the Michaelis Menten equation and its Lineweaver Burk form?

8.3. In the line weaver Burk (LB) plot the Michaelis Menten equation is converted into straight line curve. It is used to estimate the Vmax from the position of intercept on the X-axis. Straight line is given by Y = MX + C, where C is Y intercept of the regression of Y on X and M is slope.

## What do you mean by Michaelis Menten equation?

The Michaelis–Menten equation is mainly used to characterize the enzymatic rate at different substrate concentrations, but it is also widely applied to characterize the elimination of chemical (the first-order kinetics) compounds from the body.

## Which is an example of an enzyme specific reaction?

Enzymes are highly specific catalysts for biochemical reactions, with each enzyme showing a selectivity for a single reactant, or substrate. For example, the enzyme acetylcholinesterase catalyzes the decomposition of the neurotransmitter acetylcholine to choline and acetic acid.

How is the rate of an enzyme catalyzed reaction modeled?

Enzyme-catalyzed reaction rates can be modeled by Michaelis–Menten kinetics, assuming that: the timescale for conversion of the enzyme–substrate complex to the enzyme–product complex is faster than those of other reactions, hence the reaction becomes S + E ↔ C → P + E. the product never binds to the free enzyme.

### When was the equation of enzyme kinetics described?

Tthe Lineweaver–Burk plot (or double reciprocal plot) is a graphical representation of the Lineweaver–Burk equation of enzyme kinetics, described by Hans Lineweaver and Dean Burk in 1934 (Figure 3.2.2 ).

### What is the velocity of an enzyme reaction?

V is the reaction rate (velocity) at a substrate concentration [S] Vmax is the maximum rate that can be observed in the reaction substrate is present in excess enzyme can be saturated (zero order reaction)