University:
California State University, Northridge
Course:
BIOL 101 | General Biology
Academic year:

2024
Views:

317

Pages:

1
Author:

Tommy B.

CLASSIFICATION OF ENZYMES Classification of Enzymes Based on Where They Work 1. Endoenzymes called as intracellular enzymes namely the enzymes that work in the cell. This enzyme used in synthesis process in cells and for the formation of energy that useful in respiration process. 2. Exoenzymes called extracellular enzymes based on its position which work outside the cell. When susbstares digested by hidrolysis to be made into simpler molecules with a molecular weight (BM) lower so that it can pass through the cell membrane, that process used this enzyme. The energy released in substrate breakdown reactions outside the cell are not used inside cell life processes. Classification of Enzymes Based on Catalytic Power 1. Oxidoreductase. This enzyme catalyzes the oxidation-reduction reaction which is transfer of electrons, hydrogen or oxygen. Example of this enzyme is enzyme electron transfer oxidase and hydrogen peroxidase (catalase). Several types of electron transfer oxidase enzymes, namely oxidase enzymes, oxygenases, hydroxylase and dehydrogenase. 2. Transferases catalyze the removal of groups of molecules from a molecule to another molecule. For example, there are several enzymes such as following:  Transaminases are transferases that move amine groups.  Phosphorylase is a transferase that moves phosphate groups.  Transacylase is a transferase that moves acyl groups. 3. Catalase. This enzyme catalyzes hydrolysis reactions, with examples of enzymes is  Carboxylesterase is a hydrolase that hydrolyzes ester groups carboxyl.  Lipase is a hydrolase that hydrolyzes fats (lipid esters).  Peptidase is a hydrolase that hydrolyzes proteins and polypeptides. 4. Lipase functions to catalyze the taking or adding clusters of a molecule without going through the hydrolysis process. 5. Ligase enzyme catalyzes the reaction of combining 2 molecules with the release of pyrophosphate molecules from nucleoside triphosphate. Classification of Enzymes Based on How They Are Formed 1. Constitutive Enzymes. Inside the cell there are enzymes which are part of the cell structure normal so the enzyme is always present generally in a fixed amount living cells. However, there are enzymes whose amounts are influenced by levels substrate. Meanwhile, the enzymes that play a role in the respiration process the amount is not influenced by the substrate content. 2. Adaptive Enzymes. Changes in the microbial environment can induce the formation of enzymes certain. Induction causes the rate of synthesis of an enzyme to be stimulated up to several thousand times. Presence of substrate form adaptive enzyme. Example of the adaptive is the beta enzyme galactosidase produced by growing Escherichia coli bacteria in a medium containing lactose. At first Escherichia coli did not You can use lactose so it won't be visible at first growth (lag phase/long adaptation phase) after some time shows growth. During the lag phase, Escherichia coli forms the enzyme beta galactosidase which is used to break down lactose.