1. Introduction toIntroduction to
BiochemistryBiochemistry
By
Dr Khaled Saleh Algariri

2. What are seven characteristicsWhat are seven characteristics
of ALL living thingsof ALL living things
 1. Living things require food for energy
 2. Living things respire (take in oxygen gas to
 breakdown food for energy)
 3. Living things respond to the environment
 4. Living things produce waste
 5. Living things are able to repair themselves
 6. Living things grow and reproduce
 7. Living things have a limited lifespan

3. BiomoleculesBiomolecules
 Carbohydrates
 Lipids
 Proteins
 Nucleic acid

4. CarbohydratesCarbohydrates
 Composed of carbon, hydrogen, and oxygen.
 Sugars
 Monosaccharides
– Ex. Glucose
 Disaccharides
– Ex. Sucrose
 Polysaccharides
– Ex. Glycogen, Peptidoglycan

5. Carbohydrate - GlucoseCarbohydrate - Glucose
www.palaeos.com

6. Carbohydrate - SucroseCarbohydrate - Sucrose
www.chm.bris.ac.uk

7. Carbohydrate - PeptidoglycanCarbohydrate - Peptidoglycan
www.biologie.uni-hamburg.de

8. Carbohydrate - GlycogenCarbohydrate - Glycogen
www.elmhurst.edu

9. Carbohydrates most abundant organic moleculeCarbohydrates most abundant organic molecule
found in nature.found in nature.
Initially synthesized in plants from a complex seriesInitially synthesized in plants from a complex series
of reactions involving photosynthesis.of reactions involving photosynthesis.
Basic unit is monosaccharides.Basic unit is monosaccharides.
Monosaccharides can form larger molecules e.g. glycogen,Monosaccharides can form larger molecules e.g. glycogen,
plant starch or cellulose.plant starch or cellulose.
FunctionsFunctions
Store energy in the form of starch (photosynthesis inStore energy in the form of starch (photosynthesis in
plants) or glycogen (in animals and humans).plants) or glycogen (in animals and humans).
Provide energy through metabolism pathways and cycles.Provide energy through metabolism pathways and cycles.
Supply carbon for synthesis of other compounds.Supply carbon for synthesis of other compounds.
Form structural components in cells and tissues.Form structural components in cells and tissues.
Intercellular communicationsIntercellular communications

10. LipidsLipids
Fatty Acids
– The building
blocks of
lipids.
biology.clc.uc.edu
courses.cm.utexas.edu

11. LipidsLipids
Examples are:
– Waxes
– Fats and oils
– Phospholipids
– Steroids
Phospholipid Cell Membrane.

12.  Fatty acids :
 Are monocarboxylic acid contains even number C atoms
 Two types: saturated (C-C sb) and unsaturated (C-C db)
 Fatty acids are components of several lipid molecules.
 E,g. of lipids are triacylglycerol, steriods (cholestrol, sex
hormones), fat soluble vitamins.
Functions
 Storage of energy in the form of fat
 Membrane structures
 Insulation (thermal blanket)
 Synthesis of hormones

13. ProteinsProteins
 Made up of polymers
of amino acids.
 “beads on a string.”
 20 primary amino
acids exist.
 A polymer of 3 or
more amino acids
forms a polypeptide.

14. ProteinsProteins
Primary Structure
– Linear sequence of amino acids.
Secondary Structure
– Form helices or sheets due to their structure.
Tertiary Structure
– A folded protein.
Quaternary Structure
– 2 or more polypeptide chains bonded together.

15.  Amino acids:
• Building blocks of proteins.
• R Group (side chains)
determines the chemical
properties of each amino acids.
• Also determines how the
protein folds and its biological
function.
• Functions as transport
proteins, structural proteins,
enzymes, antibodies, cell
receptors.

16. EnzymesEnzymes
 Are proteins.
 Are considered
biological catalysts.
– Speed up a chemical
reaction without being
altered.
 Names often end in “-
ase.”
– Ex. Lipase,
carbohydrase.
 Act on a substrate.
 Proteins, including
enzymes, can be
denatured.

17. Nucleic AcidsNucleic Acids
DNA and RNA.
– (DNA - deoxyribonucleic acid,
RNA - ribonucleic acid).
Is the “hereditary molecule.”
Contains genes that code for a certain
product.
DNA is translated into RNA which is used
to produce a protein or other product.

18. Nucleic Acid StructureNucleic Acid Structure
DNA nucleotides
– Building blocks of DNA.
RNA nucleotides
– Building blocks of RNA.

19. Nucleic Acid StructureNucleic Acid Structure
DNA
– Nitrogenous base
– Deoxyribose
– Phosphate group
RNA
– Nitrogenous base
– Ribose
– Phosphate group
www.microbelibrary.org

20. Nitrogenous BasesNitrogenous Bases
Adenine (A)
Guanine (G)
Cytosine (C)
Thymine (T) – only DNA
Uracil (U) – only RNA
DNA and RNA

21. Nitrogenous BasesNitrogenous Bases
A and G
– Purines (double-
ring structures)
C, T, and U
– Pyrimidines
(single-ring
structures)
hyperphysics.phy-astr.gsu.edu

22. METABOLISM
• The vital activity of a living organism is determined byThe vital activity of a living organism is determined by
– the specific organization of biological structures,the specific organization of biological structures,
– metabolic processes,metabolic processes,
– energy metabolism,energy metabolism,
– genetic information transfer,genetic information transfer,
– regulatory metabolismregulatory metabolism
• The damage of any of these links develops a pathological process and aThe damage of any of these links develops a pathological process and a
disease.disease.
• An understanding of the molecular mechanisms involved in the vitalAn understanding of the molecular mechanisms involved in the vital
activity or malfunction of the organism constitutes the basis for the searchactivity or malfunction of the organism constitutes the basis for the search
and clinical applicationsand clinical applications
In the living organism there are:In the living organism there are:
• Exogenous metabolism – extracellular transformations of the materials onExogenous metabolism – extracellular transformations of the materials on
the way to their uptake and excretion from the cellsthe way to their uptake and excretion from the cells
• Intermediary metabolism – the sum of all chemical reactions that occur inIntermediary metabolism – the sum of all chemical reactions that occur in
the living cellthe living cell

23. Four major processes are involved:Four major processes are involved:
1.1. Accumulation of energy from the decomposition of compoundsAccumulation of energy from the decomposition of compounds
2.2. Utilization of energy forUtilization of energy for
• the synthesis of essential molecular components (monomers,the synthesis of essential molecular components (monomers,
macromolecules) andmacromolecules) and
• the performance of osmotic, electric or mechanical work.the performance of osmotic, electric or mechanical work.
3.3. Decomposition of renewable structural components of the cellDecomposition of renewable structural components of the cell
4.4. Synthesis and decomposition of specialized biological moleculesSynthesis and decomposition of specialized biological molecules
(hormones, mediators, cofactors etc.)(hormones, mediators, cofactors etc.)

24. METABOLISMMETABOLISM
Two processes are distinguished:Two processes are distinguished:
• catabolismcatabolism - the sum of degradative processes leading to cleavage of large- the sum of degradative processes leading to cleavage of large
molecules into smaller ones, with release of energy (stored as ATP), andmolecules into smaller ones, with release of energy (stored as ATP), and
• anabolismanabolism – the sum of processes leading to the synthesis of complex molecules– the sum of processes leading to the synthesis of complex molecules
from simpler ones, with the comsumption of energy (as ATP)from simpler ones, with the comsumption of energy (as ATP)
ATP is a coupling energetic link between the two metabolic pathways.ATP is a coupling energetic link between the two metabolic pathways.
Other simple metabolites, formed by the catabolic pathway, are startingOther simple metabolites, formed by the catabolic pathway, are starting
metabolites for the synthesis of monomers or macromolecules in themetabolites for the synthesis of monomers or macromolecules in the
anabolic pathway.anabolic pathway.
This cycle unifying the degradative and synthetic routes is calledThis cycle unifying the degradative and synthetic routes is called
amphibolic pathwayamphibolic pathway
The anabolism and catabolism areThe anabolism and catabolism are separated in spaceseparated in space..
All the processes in the living organisms areAll the processes in the living organisms are enenzymatic processeszymatic processes

25. SPECIFIC FEATURES OF METABOLISMSPECIFIC FEATURES OF METABOLISM
CATABOLISM ANABOLISM
Degradative processes Biosynthesis processes
Cleavage of large molecules
into smaller ones
Synthesis of complex
molecules
from simpler ones
Release of energy Consumption of energy
Oxidative reactions Reductive reactions
Use of oxidized coenzymes:
NAD+
, NADP+
, FAD
Use of reduced coenzymes:
NADH+H+
, NADPH+H+
, FADH2
Some metabolites which result from catabolism can be used
for the anabolism and conversely
All chemical processes proceed with the involvement of enzymes,
being regulated by alloster and feed-back mechanism

26. The EndThe End
ThanksThanks