A very informative video about enzyme for better understandings

1. INTRODUCTION TO
ENZYMES
UMER ALI
MPHIL BIOTECHNOLOGY
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2. STUDENT LEARNING OUTCOME
By the end of this lecture, the student should be able to:
Define enzymes and related terms ( active site, apoenzyme, holoenzyme, prosthetic group,
enzyme specificity).
Describe the structure of enzymes.
Know the mechanism of action
Explain the classification of enzymes
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3. WHY ARE ENZYMES SO IMPORTANT
Enzymes are very crucial and are part of metabolism, diagnosis, and therapeutics.
 All biochemical reactions are enzyme catalyzed in the living organism.
Level of enzyme in blood are of diagnostic importance e.g. it is a good indicator in disease
such as myocardial infarction.
Enzyme can be used therapeutically such as digestive enzymes.
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4. WHAT ARE ENZYMES
Enzymes are biocatalysts that boast the biocatalytic
reactions.
Most enzymes are proteins in nature except to the rna
moiety called ribozymes.
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5. HOW DO ENZYMES WORK
• Enzymes works by
lowering the activation
energy of a biochemical
reaction.
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6. ACTIVE SITE
• It is the small region of enzyme.
• Active site is the portion of enzyme
where the substrate binds to perform the
catalytic activity.
DNA ploymerase 6

7. CO-FACTORS
• NON PROTEIN PART
Tightly Bound cofactor is
Prosthetic Group
Loosely bound cofactor is
Coenzymes.
Mostly vitamins are
coenzymes
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8. COFACTOR
• Enzymes with cofactor removed are called as
APOENZYMES.
• Enzymes with their cofactors attached as
HALOENZYMES.
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9. SUBSTRATE
• The entity which is catalysed by enzyme is called as substrate.
• We can say that the substrates are the reactants of enzyme catalysed reactions.
• Enzymes are very specific to their substrates.
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10. LOCK AND KEY MODEL
• Important features of LOCK AND KEY HYPOTHESIS are:
• The shape of active site is fixed.
• Substrates can only be catalysed if they are perfectly fits to the active site.
• Substrates can acts as key and when it fits to the lock of active site then
biochemical reaction can be catalysed.
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11. THE LOCK AND KEY HYPOTHESIS
Enzyme may be
used again
Enzyme-
substrate
complex
E
S
E
E
P
P
Reaction
E

12. INDUCE FIT HYPOTHESIS
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13. INDUCE FIT HYPOTHESIS
It is more accurate model.
Some enzymes undergoes conformational changes as compared with most of the enzymes.
The active site can change its shape with respect to the specific substrate during
biochemical reaction.
Induce fit hypothesis conforms the specificty of enzymes.
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14. ACTIVATORS VS INHIBITORS
• Substances that enhances the catalytic activity of enzymes are called as activators.
• Substances that restricts the catalytic activity of enzymes are called as inhibitors
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15. NOMENCLATURE OF ENZYMES
• Common method of naming the enzyme was adding suffix –ase at the end of substrate at
which enzyme act for example
• Lipase acts on lipid and sucrase acts on sucrose.
• The systemic name called as enzyme comission number e.C is given to every enzyme based
on the class ,sub class , sub sub class and individual enzyme.
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16. CLASSES OF ENZYMES
• Enzymes are classified into six functional classes (EC number
classification) by the international union of biochemists (I.U.B.).
On the basis of the types of
reactions that they catalyze
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17. CLASSES OF ENZYMES
• EC 1. OXIDOREDUCTASES
• EC 2. TRANSFERASES
• EC 3. HYDROLASES
• EC 4. LYASES
• EC 5. ISOMERASES
• EC 6. LIGASES
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