This document provides an introduction to biochemistry and enzymes. It discusses that enzymes are protein biocatalysts that increase the rate of chemical reactions without being consumed. They are colloidal, thermolabile, and specific in their action. Enzymes are composed of an apoenzyme protein component and sometimes a coenzyme or prosthetic group non-protein component. The functional unit is called the holoenzyme. Enzymes can be monomeric consisting of a single polypeptide or oligomeric consisting of multiple subunits.

1. BIOCHEMISTRY
Presented By:
Ms. Sayali Dilip Powar
(M. Pharm )
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Content of Syllabus

3. INTRODUCTION
Enzymes
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4. INTRODUCTION
• Enzymes are biocatalysts – the catalysts of life.
• A catalyst is defined as a substance that
increases the velocity or rate of a chemical
reaction without itself undergoing any change
in the overall process.
• Enzymes may be defined as biocatalysts
synthesized by living cells.
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5. INTRODUCTION
• Berzelius in 1836 coined the term catalysis
(Greek : to dissolve).
• In 1878, Kuhne used the word enzyme (Greek
: in yeast) to indicate the catalysis taking
place in the biological systems.
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6. PROPERTIES
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7. PROPERTIES
• They are protein in nature (exception – RNA
acting as ribozyme)
• colloidal
• thermolabile in character
• specific in their action.
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8. PROPERTIES
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10. PROPERTIES
• All the enzymes are invariably proteins.
• In recent years, however, a few RNA molecules have been
shown to function as enzymes. Each enzyme has its own
tertiary structure and specific conformation which is very
essential for its catalytic activity.
• The functional unit of the enzyme is known as holoenzyme
• Holoenzyme made up of apoenzyme (the protein part) and a
• coenzyme (non-protein organic part).
Holoenzyme Apoenzyme + Coenzyme
(active enzyme) (protein part) (non-protein part)
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•The term prosthetic group is used when the non-
protein moiety tightly (covalently) binds with the
apoenzyme.
•The coenzyme can be separated by dialysis from the
enzyme while the prosthetic group cannot be.
•The word monomeric enzyme is used if it is made up
of a single polypeptide e.g. ribonuclease, trypsin.
•Some of the enzymes which possess more than one
polypeptide (subunit) chain are known as oligomeric
enzymes e.g. lactate dehydrogenase, aspartate .
• There are certain multienzyme complexes possessing
specific sites to catalyse different reactions in a
sequence.