Metabolism

1. General Overview
of the Course

2. Outline
Understanding of key terms
• Biochemistry
• Cell
• Metabolism
• Importance of metabolism
• Role of enzymes in metabolism
• Metabolic path way.

3. What is Biochemistry
•Biochemistry is the application of chemistry to
the study of biological processes at the cellular
and molecular level.
•It emerged as a distinct discipline around the
beginning of the 20th century when scientists
combined chemistry, physiology and biology to
investigate the chemistry of living systems by:

4. A. Studying the structure and behavior of the
complex molecules found in biological
materials and
B. The ways these molecules interact to form
cells, tissues and whole organism
Biochemistry has become the foundation for
understanding all biological processes. It has
provided explanations for the causes of many
diseases in humans, animals and plants."

5. Principles of Biochemistry
• Cells (basic structural units of living organisms) are highly organized
and constant source of energy is required to maintain the ordered
state.
• Living processes contains thousands of chemical reactions. Precise
regulation and integration of these reactions are required to maintain
life
• Certain important reactions E.g. Glycolysis is found in almost all
organisms.
• All organisms use the same type of molecules: CHO, proteins, lipids &
nucleic acids.
• Instructions for growth, reproduction and developments for each
organism is encoded in their DNA

6. What is a cell?
• The word cell comes from the Latin word "cella", meaning
"small room", and it was first coined by a microscopist
observing the structure of cork.
• The cell is the basic unit of all living things, and all organisms
are composed of one or more cells.
• Cells are so basic and critical to the study of life, in fact, that
they are often referred to as "the building blocks of life".
• Organisms - bacteria, amoebae and yeasts, for example -
may consist of as few as one cell, while a typical human body
contains about a trillion cells.

7. Metabolism

8. • Metabolism is a network of metabolic /biochemical
reactions.
• Carried out in living cells.
• In a well organized, integrated and regulated manner.
• Related to various biomolecules viz
• Carbohydrates
• Lipids
• Proteins
• Nucleoproteins

9. •Metabolism involves
interconversions of chemical
compounds in the body.
• Metabolite precursors are
transformed to end products via
many specific intermediates.

10. •Metabolism is the sum of the
chemical changes that convert:
•Nutrients into energy.
•Chemically complex substances of
cells into simpler forms.
•Chemically simple substances into
functional complex biomolecules.

11. The Sun is Energy for Life
Phototrophs (Plants) use light to drive
synthesis of organic molecules.
Heterotrophs (Animals) use these as
building blocks.
CO2,O2 and H2O are recycled.

13. Importance Of Metabolism
•Normal Metabolism is vital for
health, growth, reproduction
and good survival of human
beings.

14. Role of Enzymes and Hormones
in Metabolism

15. •Enzymes along with Coenzymes
biocatalyze specific metabolic
reactions.
•Thus Enzymes are “Functional
units of Metabolism”

16. •Hormones are chemical
messengers of human body. They
are regulators of Enzyme activity.
(Hormones Stimulate/Inhibit
Enzyme activity)

17. •Enzyme reactions are
organized into discrete
pathways.

18. Metabolite
•Metabolite is a substrate or a
reactant undergoing a
biochemical/metabolic reaction.

19. Metabolic Reaction
•Metabolic reaction is a biochemical
reaction where a metabolite is specifically
reacted by an Enzyme and Coenzyme to
give a product.
A E-Co B

20. Types Of Metabolic Reactions
• Reversible Reactions – Same Enzyme is required.
• Not regulatory steps.
E1
A E1 B

21. • Irreversible Reactions-
•Different set of Enzyme required.
•Non equilibrium Reactions.
•Regulatory steps.
E2
C E3 D

22. Types Of
Biochemical Reactions

23. • Oxidation/Dehydrogenation/Hynroxylation
• Reduction
• Hydrolytic
• Carboxylation
• Decarboxylation
• Phosphorylation
• Dephosphorylation
• Amination
• Deamination
• Isomerization
• Hydration
• Dehydration

24. Metabolic Pathway
•Metabolic pathway is a series of well
defined and significant biochemical
reactions followed one after another
giving intermediate products and
finally end product of the pathway.

25. Types Of Metabolic Pathway
•Catabolic/Degradative /Energy
Generating/ATP producing
Pathways/Exothermic.
•Anabolic/Synthetic/Energy Utilizing/
ATP Using Pathways/Endothermic.

26. •Catabolic pathways involve
oxidative reactions producing
reducing equivalents-
NADH+H+
and FADH2.
•Catabolic pathways converge
to few end products.

27. •Anabolic pathways
diverge to synthesize
many biomolecules.

30. •Some pathways serve both in
catabolism and anabolism ,those
are Amphibolic pathways.

31. •Amphibolic Pathways occur at the
crossroads of metabolism.
•Amphibolic pathways links between
Anabolic and Catabolic pathways.

32. Regulation of Metabolic
Pathways

33. •Regulation means stimulation and
inhibition of pathways as per cellular
need.
•Hormones regulate the metabolic
pathways.
•Metabolic pathways are regulated to
allow the organism to respond to
changing conditions.

34. •Every metabolic pathway has its
specific regulatory enzymes/key
enzymes.
•Hormones regulate by either
stimulating /inhibiting the
regulatory/key enzymes of the
pathway.

35. •Knowledge of normal metabolism
is essential for :
•Understanding adaptations of
Starvation
Exercise
Pregnancy and lactation.
•Understanding of metabolic
disorders.

36. Abnormal Metabolism Is Due To
Nutritional Deficiencies
Enzyme Defects
Hormonal Defects
Drug and Toxin Interactions