Enzymes

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BIOTECHNOLOGY ASSIGNMENT
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Topic: Enzymes and their Industrial importance

Table of contents

Definition of enzyme……….……………………..3
Composition of enzymes…………………………..3
Characteristics of enzymes………………………..3
Functions……..……………………………………..3 Discovery………..…………………………………...5 Explanation…………………………………………..6 Types of enzymes...............................................…...6 Working………………………………………………6 Sources of enzymes………………………………….7

Industrially important enzymes……………….…10
Some other uses…………………………………….11 Bar graph…………………………………………....12 References…………………………………………..13

ENZYMES
Definition:
Enzymes are the most important group of proteins that are produced by the living organisms that acts as a catalyst to bring about a specific biochemical reaction. Composition:
Enzymes are composed of hundreds of amino-acids joined together and coiled upon them-selves to form a globular structure. The catalytic activity is restricted to small area known as active site. Some enzymes consist solely of proteins, while other has a non-protein part known as cofactor. The detachable cofactor is known as activator. If the non-protein part is covalently bonded it is known as prosthetic group but if it is loosely attached it is known as coenzyme. Characteristics of Enzymes:

* All enzymes are globular proteins.
* They increase the rate of chemical reaction without themselves being used up. * There presence does not affect the nature or the properties of end products. * They are specific in action.

* They lower the activation energy of reactions.
Function:
Enzymes are important proteins that catalyze the chemical reactions. In enzymatic reactions, the molecules at the beginning of the process on which the enzyme attack are called substrates, and the enzyme converts them into different molecules, called the products. Discovery:

The discovery of enzymes is an important achievement. Many scientists contributed in the discovery of enzymes. Some of them are discussed as following: * PAYEN and PERSOZ:
In 1833 they treated an aqueous extract of malt with ethanol and precipitated a heat-labile substance which promoted the hydrolysis of starch. They called their fraction DIASTASE (from the Greek word meaning separation).

Eduard Buchner:
Buchner discovered in 1897 that yeast extracts could ferment sugar to alcohol: C6H12O6 → 2C2H5OH + 2CO2+ 2 ATP
Buchner’s finding showed that fermentation was promoted by molecules that continued to function when removed from cells.

Sumner James:
In 1926, Sumner isolated and crystallized jack bean urease, which catalyzes the reaction:

CH4N2O + H2O → 2NH3 + CO2

The urease crystals contained only protein, leading Sumner to propose that all enzymes are proteins. He received a Nobel Prize in 1946 for this discovery.

J.B.S Haldane:
In the 1930s, Haldane postulated that weak bonding interactions between an enzyme and its substrate might be used to catalyze a reaction. This leads to our current understanding of enzyme catalysis.

Explanation:
Most enzymes are proteins, and they often use metal ions or prosthetic groups like vitamins to carry on catalysis. Many inherited genetic disorders result from a defect or even a total absence of a particular enzyme, or excessive activity of an enzyme. Measurement of enzyme activities in body fluids is important in diagnosing various illnesses. Furthermore, many drugs act by altering the activities of enzymes. Types of enzymes:

* Apoenzymes : enzymes that lack the prosthetic group
* Holoenzymes :enzymes that contain the prosthetic group and are fully functional. Working:
A simple equation for an enzyme-catalyzed reaction can be written as:

Enzyme + Substrate Enzyme Substrate complex Enzyme + Product

Sources of enzymes:
The sources of enzymes are plant or animal tissues and microorganisms mostly bacteria and fungi. Microorganisms are used in the manufacture of fermented foods...
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