Question

An enzyme is given a four-digit number in the system of universal nomenclature. The first digit for enzyme lipase is
(a) Four
(b) Six
(c) Two
(d) Three

Answer 1

Enzymes are the proteinaceous catalyst that helps to fasten the rate of reaction. For the numerical classification of enzymes done based on The enzyme classification number which consists of a four-digit number and six groups and the lipase belong to the group of hydrolases.

Complete answer:
The enzyme classification (EC) number helps in the classification of enzyme-based on digits. These first digits define the types of enzymes that help to catalyze the reaction. The second digits help in the recognition of class. The third digits define the subclass and the fourth digits are the serial number of the enzyme in the sub-subclass. The enzyme classification is described into six groups. EC1 defines oxidoreductases which help in the catalyzation of reaction in oxidation and reduction and it consists of dehydrogenase and oxidase. EC2 defines the transferases and it helps in the transfer of functional groups consisting of transaminase and kinase. EC3 defines the hydrolases and helps in the formation of the product by hydrolysis and consist of lipase, amylase and peptidase. EC4 molecule lyases in addition and removal of the substrate from the group non hydrolytically and consist of decarboxylase. EC5 defines isomerase and helps in intramolecular rearrangement and consists of isomerase and mutase. EC6 defines ligases and it helps to join two molecules together for the formation of a new molecule and it consists of synthetase.

So, the correct answer is 'Three'.

Note:
The enzyme classification number system was given by the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology in 1992 whereas it was first set up by the International Congress of Biochemistry in 1955 in Brussel.