Frequently Asked Questions on Enzyme Catalysts

Ans. Enzyme inhibitors are those substances that reduce the rate of a chemical reaction. They usually increase the activation energy of a reaction and stop it from occurring. Enzyme inhibitors include chemicals like pesticides, bacteria, pathogens, etc.

Enzyme inhibitors can react in two ways to stop the chemical reaction – which means attacking the activation site. Some may act as competitive inhibitors, and others may act as allosteric inhibitors and thus decrease enzyme activity.

Ans. Enzymes can perform well and show the best activity at a certain pH range. If the pH is very low, enzymes can get deactivated, and if the pH is very high, they can get denatured. If the pH range is between 7.2-7.4, then the enzyme activity is efficient and is said to be the optimum pH range.

Ans. Enzyme activity can be affected by a change in temperature. At high temperatures, enzymes can get denatured or decomposed, and at low temperatures, enzymes get deactivated. So the optimum temperature for the enzyme activity to be efficient is between 25-55°C.

Ans. Cofactors are those groups that attack the enzymes and activate them. Without cofactors, enzymes are inactive. Usually, transition metal cations act as enzyme activators. These increase the activity of an enzyme in a given chemical reaction.

Examples: Fe+2, Mn+2, Mo+2, Cu+2

Ans. Cane sugar is sucrose sugar, commonly called table sugar. This is a disaccharide formed by the combination of glucose and fructose. Sucrose is catalysed by an enzyme called invertase. Sucrose is hydrolysed by an enzyme sucrase or by using dilute acids, which liberates one molecule each of ∝-D-Glucopyranose and ß-D-fructofuranose. 

The second molecule, ß-D-fructofuranose, is an unstable compound and gets converted into ß-D-fructopyranose immediately. This compound is a laevorotatory compound with specific rotation (-92). This effect of converting a dextrorotatory compound (+66.5) to a levorotatory compound (-22.8) by hydrolysis is called the inversion of sugar.

Ans. The excretory product of human beings is urea in the form of urine. Urea present in the urine is hydrolysed to form ammonia by an enzyme called urease. Urease catalyses this reaction. In this process, moisture and oxygen present in the air react with it, giving a bad, offensive odour.

Ans. The enzyme used in hydrolysing starch to maltose is the amylase enzyme. Starch is a polysaccharide and contains many units of monosaccharides in it.

Ans. Enzymes have active sites on them with specific shapes and structures similar to the substrate. According to the specific substrate, the active sites of enzymes will be variable, leading to specificity in the reaction.

Ans. Enzymes are protein sources that are formed by chains of amino acids in various combinations. Enzymes are formed by linking amino acids in various combinations by protein synthesis, which occurs in ribosomes by RNA.

Ans. Enzymes are biological substances that are made of amino acid groups. These amino acids link in a particular sequence and form proteins. Each protein is highly specific, which means the sequence of amino acids of one protein does not match the other.

Proteins act as catalysts, meaning they increase the rate of a reaction without participating in the reaction. A particular protein catalyses only a particular reaction and is not involved in any other reaction.

Example: Lipases are enzymes that break down fats, urease breaks down urea, and similarly, amylase breaks down starch.

The action of an enzyme with a particular substrate of a reaction is called the specificity of an enzyme.