The role of metabolites (which are intermediates in the metabolic cycles) is discussed in this presentation.

1. Role of Metabolites in
Metabolism
Chinnathambi S M.Sc.,
Microbiologist
chinnaselvamc345@gmail.com
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2. Why do we need to know about
metabolites…?
 Energy production
 Biomolecule synthesis
 Cell signaling
 Biotechnology
 Environmental monitoring
 Nutrition
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3. “
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⬢ INTRODUCTION
⬢ FUNCTION
⬢ CLASSIFICATION
⬢ ROLE OF PRIMARY METABOLITES
⬢ ROLE OF SECONDARY
METABOLITES
⬢ REFERENCES
TABLE OF CONTENTS

4. INTRODUCTION
Metabolites
The intermediate products that are formed during metabolism and catalyzed by
several enzymes that occur in the cells naturally are called metabolites. They can
be any substance synthesized or modified by a metabolic process, often
understood to mean an intermediate or final product in the breakdown from a
parent molecule.
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5. Function of metabolites
 Energy conversion
 Epigenetic influence
 Cofactor activity
 Fuel
 Structure
 Signalling
 Stimulatory and inhibitory effects on enzymes
 Catalytic activity of their own (usually as a cofactor to an enzyme)
 Defence
 Interactions with other organisms.
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Metabolites

6. Classification
Metabolites are generally classified into two classes
1)Primary metabolites
2) Secondary metabolites
According to their role and function in the various metabolic, regulatory, cell growth,
maintenance, and cell to cell communication.
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7. Primary metabolites
Primary metabolites are the compounds that are directly involved in the
metabolic pathways of an organism necessary for its growth, development, and
reproduction.
Primary metabolites are divided into two groups:
1) Primary essential metabolites- Eg: Proteins and carbohydrates
2) Primary metabolic end products.- Eg: Lactic acid and ethanol
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8. Secondary metabolites
Secondary metabolites are the organic compounds that are produced by various
organisms that are not directly involved in the growth, development, or reproduction
of the organism but are essential in the ecological and other activities.
Eg:
o Steroids
o Essential oils
o Phenolics
o Alkaloids
o Pigments
o Antibiotics
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9. Role of primary metabolites in metabolism
1)Carbohydrates
In every micro and macro living systems (Animal, Plant, Microbes) these synthesized carbohydrates as
primary metabolites broken down to yield energy from it through the cellular respiration.
Eg:
 Anabolic cycles- Calvin cycle, Starch cycle (In plants)
Gluconeogenesis, glycogenesis (In animals)
 Catabolic cycles-Glycolysis (Both plants and animals)
Glycogenolysis (In animals)
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10. 2)Proteins:
Proteins are classified into two classes namely catalytic and non-catalytic. Enzymes are the key
regulators which induces the catalytic action to convert complex molecules into simple molecules.
Non catalytic proteins are acting as the precursors for synthesis of glucose, hormones by using the
carbon skeletons.
Examples:
Anabolism of proteins - Translation via gene expression
Catabolism of proteins – Urea cycle, proteolysis, deamination.
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11. 3)Lipids
Fatty acid oxidation (FAO), which mostly occurs in the mitochondria, converts
fatty acids to acetyl-CoA. Lipids also acts as the precursors for most of the
hormone synthesis.
Example: Cholesterol – precursor for sex steroids.
Fatty acids – precursor for glucose synthesis. (Gluconeogenesis)
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12. 4)Nucleic acid components
Example:
Anabolic cycles – salvage, denovo pathways
Catabolic cycles – urea cycle.
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13. 5)Vitamins and Minerals
Binding of these substances into the active site of an enzyme can induce the
catalysis of biological macromolecules.
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14. Role of secondary metabolites in
metabolism
Microbial secondary metabolites are low molecular mass products, not essential for
growth and metabolism. However, these serves as competitive weapons used against
other bacteria, fungi, amoebae, plants, insects and even large animals.
But exceptional cases in Eukaryotes(plants).
1) Steroids
2) Plant hormones
Examples: Auxin, Cytokinin, Gibberellin, Ascorbic acid.
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15. THANKS!
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