LIPIDS
Daniel Bučánek
Jan Gembík
Lipids
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Fatty acids
Glycerides
Nonglycerol lipids
Complex lipids
Types of lipids
Fatty acids
Glycerides
Saturated
Neutra
Unsaturated
Phospoglycerides
Nonglycerides
Complex lipids
Sphingolipids
Lipoproteins
Steroid
Glykolipids
Waxes
Lipid functions
Cell membrane structure
• Creates a barrier for the cell
• Controls flow of materials
Energy storage
• Fats stored in adipose tissue
Hormones and vitamins
• Hormones – communication between cells
• Vitamins – assist in the regulation of biological
processes
Fatty acids structure
Long chain monocarboxylic acids
CH3(CH2)nCOOH
• Size range: C12 – C14
• Always an even number of carbon
• Saturated – no double bonds
• Unsaturated – one or more double bonds
Fatty acids structure
Saturated
O
CH2
H3C
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
C
CH2
OH
Unsaturated
CH
cis
CH2 CH2
CH
O
CH2 CH2
CH2 CH2
C
CH2 CH2
H3C
CH
CH2 CH2
CH
trans
O
CH2
H3C
CH2
CH2
CH
CH2
CH2
CH
CH2
CH2
CH
CH2
CH2
CH
C
CH2
OH
OH
Some common fatty acids
Common
name
IUPAC name
MP °C
Formula
Presence of double bonds reduced melting point. In nature,
all double bonds are ´cis´.
Steric acid
Oleic acid
Reactions of fatty acids
React like any other carboxylic acid.
Unsaturated fatty acids eicosanoids
Eicosanoids
• All are unsaturated.
• All have twenty carbons.
• Some are essential fatty acids
Can´t be produced by the body.
examples: linoleic and linoleic acids
Three groups: prostaglandins, leukotrienes, thromboxanes
Prostaglandins
Originaly isolated from seminal fluid.
All are derived from arachidonic acid.
Prostaglandins
Prostaglandins
Biological effect
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Stimulation of smooth muscles
Regulation of steroid production
Inhibition of gastric secretion
Inhibition of hormone-sensitive lipases
Inhibition / stimulation of plate aggregation
Regulation of nerve transmission
Sensitization of pain
Mediation of inflamantory response
Blood clotting
Thromboxane A2
Produced by platelets in blood.
Stimulates constrictions of blood vessel.
Aggregation of platelets.
Prostacyclin
Produced by cells that line blood vessels.
Reverses effects of throbmoxane A2
Aspirin therapy
Acts as anticoagulent – antiplatelet aggregation.
Inflammantory response
Protective mechanism when tissue is damaged.
Ressults in swelling, redness, fever and pain.
Prostaglandins promote this response.
Drug like aspirin and ibuprofen
• Anti - inflammatories
• Block prostaglandins synthesis
• Cause reduction in this response
Neutral glycerides
Ester of glycerol and fatty acid.
Principal function is energy storage – fat or oil.
CH2 OH
O
+
OH
HC
OH
CH2 OH
O
CH2 O
HC
CH3
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
C
OH
CH2 OH
CH3
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
CH2
C
Fats and oils
• Both are triglycerides
• Fats
• typically obtained from animals
• solids at room temperature
• made from saturated fatty acids
• Oils
• typically obtained from plants
• liquids at room temperature
• made from unsaturated fatty acids
Waxes
• Water insoluble and hard to hydrolyze
• Often used to provide a protective coating
(leaves, skin, fur, hair….)
• Bees wax and Sebum are examples
• Ester of a fatty acid and a long chain alcohol
Phospoglycerides
Lipids that contain a phosphate group.
Modified fat where a phospate replaces one of
the fatty acid chain.
Uses
• production of cell membrenes
• emulsifying agents
Lecithin-phosphatidylcholin
Polar head
Nonpolar tail
Nonglycerol lipids
Sphingolipids
• A type of phospolipid not derived from fat.
• Used primarily in nerve tissue – myelin sheath.
• In people, 25% of all lipids are sphingolipids.
Steroids
Broad class of compounds that all have the same base structure.
Cholesterol
Principal membrane lipid for
fluidity.
Complex lipids
• Lipids bound to other molecules
• Combination results in the structure
Complex lipids
Four major classes of plasma lipoproteins
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Chilomikrons
Very low-density lipoproteins (VLDL)
Low-density lipoproteins (LDL)
High-density lipoproteins (HDL)
Each is composed of several types of lipids
Composition of complex
lipoproteins
Composition of complex
lipoproteins
Function of lipoproteins
• Chilomikrons
Transport triglicerides from intestines to other tissue –
except kdneys
• VLDL
Bind triglycerides in liver and carry them to fat tissue
• LDL
Carry choresterol to peripheral tissue
• HLD
Bound to plasma choresterol
Transport cholesterol to liver
Transport of lipoproteins
Source
• Some information from internet.
• Some information from lecture of
Biochemistry.
• And some information from 12.Lesson with
name Biochemistry.