5. Contents
Introduction
Characteristics of Enzymes
Enzyme Classification
Function of Enzymes (Biological & Industrial)
Examples of Enzymes
Properties of Enzymes
Structure of Enzymes
Metabolism Of Enzymes
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6. Introduction
• Enzymes are large biomolecules that are responsible for many
chemical reactions that are necessary to sustain life.
• Enzyme is a protein molecule and are biological catalysts.
• Enzymes increase the rate of the reaction.
• Enzymes are specific, they function with only one reactant to
produce specific products.
• Enzymes have a three-dimensional structure and they utilize
organic molecules like biotin and inorganic molecules like
metal ions (magnesium ions) for assistance in catalysis.
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7. Characteristics of Enzymes
Characteristics of enzymes are as follows:
1. Enzymes possess great catalytic power.
2. Enzymes are highy specific.
3. Enzymes show varying degree of
specificities.
4. Absolute specificity where the enzymes react
specifically with only one substrate.
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8. 5. Enzymes have an optimum pH range within
which the enzymes function is at its peak.
6. The enzyme activity can be controlled but
the activity of the catalysts can not be
controlled.
7. All enzymes are proteins.
Characteristics of Enzymes
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9. 8. Like the proteins, enzymes can be coagulated
by alcohol, heat, concentrated acids and
alkaline reagents.
9. At higher temperatures the rate of the reaction
is faster.
10.The rate of the reaction involving an enzyme
is high at the optimum temperature.
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Characteristics of Enzymes
10. Enzyme Classification
• The current system of nomenclature of
enzymes uses the name of the substrate or the
type of the reaction involved, and ends with "-
ase". Example:'Maltase'- substrate is
maltose. 'Hydrolases'- reaction type is
hydrolysis reaction.
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11. Classification of enzymes
• Enzymes are classified based on the
reactions they catalyze into 6 groups:
1. Oxidoreductases
2. Transferases
3. Hydrolases
4. Lyases
5. Isomearses
6. ligases
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12. • Oxidoreductases - Oxidoreductase are the
enzymes that catalyze oxidation-reduction
reactions. These emzymes are important as these
reactions are responsible for the production of
heat and energy.
• Transferases - Transferases are the enzymes that
catalyze reactions where transfer of functional
group between two substrates takes place.
Enzyme Classification
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13. • Hydrolases - Hydrolases are also known as
hydrolytic enzymes, they catalyze the hydrolysis
reactions of carbohydrates, proteins and esters.
• Lyases - Lyases are enzymes that catlayze the
reaction invvolving the removal of groups from
substrates by processes other than hydrolysis by
the formation of double bonds.
Enzyme Classification
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14. • Isomerases - Isomerases are enzymes that
catalyze the reactions where interconversion of
cis-trans isomers is involved.
• Ligases - Ligases are also known as synthases,
these are the enzymes that catalyze the
reactions where coupling of two compounds is
involved with the breaking of pyrophosphate
bonds.
Enzyme Classification
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15. Function of Enzymes
• Biological Functions of Enzymes:
1. Enzymes perform a wide variety of functions in
living organisms.
2. They are major components in signal transduction
and cell regulation, kinases and phosphatases help in
this function.
3. They take part in movement with the help of the
protein myosin which aids in muscle contraction.
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16. Biological Functions of Enzymes
4. Also other ATPases in the cell membrane acts
as ion pumps in active transport mechanism.
5. Enzymes present in the viruses are for
infecting cell.
6. Enzymes play a important role in the
digestive activity of the enzymes.
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17. 7. Amylases and proteases are enzyme so that
breakdown large molecules into absorbable
molecules.
8. Various enzymes work together in a order
forming metabolic pathways. Example:
Glycolysis.
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Biological Functions of Enzymes
18. Industrial Application of Enzymes:
1. Food Processing - Amylases enzymes from fungi
and plants are used in production of sugars from
starch in making corn-syrup.
2. Catalyze enzyme is used in breakdown of starch into
sugar, and in baking fermentation process of yeast
raises the dough.
3. Proteases enzyme help in manufacture of biscuits
in lowering the protein level.
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19. 4. Baby foods - Trypsin enzyme is used in pre-
digestion of baby foods.
5. Brewing industry - Enzymes from barley are
widely used in brewing industries.
6. Amylases, glucanases, proteases,
betaglucanases, arabinoxylases,
amyloglucosidase, acetolactatedecarboxylases
are used in prodcution of beer industries.
Industrial Application of Enzymes:
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20. 7. Fruit juices - Enzymes like cellulases,pectinases
help are used in clarifying fruit juices.
8. Dairy Industry - Renin is used inmanufacture of
cheese. Lipases are used in ripening blue-mold
cheese. Lactases breaks down lactose to glucose
and galactose.
9. Meat Tenderizes - Papain is used to soften
meat.
Industrial Application of Enzymes:
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21. 10.Starch Industry - Amylases, amyloglucosidases
and glycoamylases converts starch into glucose
and syrups.
11.Glucose isomerases - production enhanced
sweetening properties and lowering calorific
values.
12.Paper industry - Enzymes like amylases,
xylanases, cellulases and liginases lower the
viscosity, and removes lignin to soften paper.
Industrial Application of Enzymes:
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22. 13. Biofuel Industry - Enzymes like cellulases are
used in breakdown of cellulose into sugars which
can be fermented.
14.Biological detergent - proteases, amylases,
lipases, cellulases, asist in removal of protein
stains, oily stains and acts as fabric conditioners.
15.Rubber Industry - Catalase enzyme converts
latex into foam rubber.
Industrial Application of Enzymes:
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23. Examples of Enzymes
1. Oxidases: These oxidase substances to alcohols or
ketones etc.
2. Hydrolases: These breakdown materials by the
addition of water.
3. Reductases: These add hydrogen to substrates in the
reaction.
4. Lyases: The enzymes which are involved in
breaking of molecules without hydrolysis or
oxidation.
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24. 5. Ligases: Enzymes which brings in a bonding of two
or more molecules.
6. Isomerases: These enzymes convert the same
molecule from one form to another and vice versa.
7. Transaminases: These are the enzymes involved in
the addition or removal of amino acids.
8. Glycogen synthase: This is the enzyme which
synthesizes glycogen from glucose to store in the
liver.
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Examples of Enzymes
25. 9. Aminoacyl tRNA synthetase: This enzyme
bind amino-acid to tRNA.
10. Lactate dehydrogenase: Enzymes which
converts lactate to pyruvic acid
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Examples of Enzymes
26. Properties of Enzymes
1. Catalytic Property
2. Specificity
3. Heat Destruction
4. Enzyme Inhibitors
5. High Molecular Weight
6. Colloidal
7. Water Soluble
8. Reversibility of Action
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27. Structure of Enzymes
• Enzymes are proteins, like the proteins the enzymes
contain chains of amino acids linked together.
• The characteristic of an enzyme is determined by the
sequence of amino acid arrangement.
• When the bonds between the amino acid are weak,
they may be broken by conditions of high
temperatures or high levels of acids.
• When these bonds are broken, the enzymes become
nonfunctional.
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28. Structure of Enzymes
• Enzymes are highly selective, they catalyze
specific reactions only.
• Enzymes have a part of a molecule where it just
has the shape where only certain kind of substrate
can bind to it, this site of activity is known as
the 'active site'.
• The molecules that react and bind to the enzyme
is known as the 'substrate'.
•
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30. Structure of Enzymes
• Most of the enzymes consists of the protein and
the non protein part called the 'cofactor'.
• The proteins in the enzymes are usually globular
proteins. The protein part of the enzymes
are known 'apoenzyme', while the non-protein part
is known as the cofactor.
• Together the apoenzyme and cofactors are known
as the 'holoenzyme'.
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32. What Is the Role of Enzymes in
Metabolism?
• Mitochondria play important roles in metabolism and
protein production.
• Metabolism refers to any chemical process occurring
within or between cells. There are two types of
metabolism:
1. Anabolism, where smaller molecules are synthesized to
make larger ones; and
2. Catabolism, where larger molecules are broken down into
smaller ones.
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33. What Is the Role of Enzymes in
Metabolism?
• Most chemical reactions within cells require a
catalyst to get started. Enzymes, which are
large protein molecules found in the body,
provide the perfect catalyst because they can
change the chemicals within the cells without
changing themselves.
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34. Metabolism Explained
• Metabolism is an umbrella term referring to any
cellular process that involves a chemical reaction.
• Glycolysis is an example of a catabolic cellular
process;
• in this process, glucose is broken down into pyruvate. When
oxygen and hydrogen combine to form water at the end of the
electron transport chain, that is an example of an anabolic
process, where smaller molecules combine to make a larger
molecule.
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