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Phospholipids, or glycerol phospholipids, are derivatives of phosphatidic acid (glycerol-3-phosphoric acid). According to the type of substituent attached to phosphatidic acid, phospholipids are further divided into:

  1.  Phosphatidylcholines (lecithins)
  2.  Phosphatidylethanolamines (kephalins)
  3. Phosphatidylserines
  4.  Plazmalogens
  5.  Phosphatidylinositols

Phosphatidylcholines (lecithins)[edit | edit source]

  • They contain choline, a quaternary nitrogen base
  • They are a part of the cell membrane
  • A large part of the body's supply of choline (important for the transmission of nerve impulses)
  • Waxy, colorless compounds with hydrophilic and hygroscopic features
  • They form colloid solutions in the water, create internal salts, reduce surface tension, good emulsifying agents
  • Easily hydrolyzed in the body due to the action of phospholipases
  • Dipalmitoyllecithin – surfactant
Searchtool right.svg For more information see Phosphatidylcholine.

Phosphatidylethanolamines (kephalins)[edit | edit source]

  • They contain ethanolamine bound by an ester bond to the second acid group of phosphoric acid
  • Similar character as phosphatidylcholines

Phosphatidylserine[edit | edit source]

  • It contains serine amino acid
  • It is found in most tissues

Plazmalogens[edit | edit source]

  • The fatty acid is replaced at position 1 by an ether-linked higher unsaturated alcohol
  • Similar to lecithins and kephalins
  • Synthesized on peroxisomes by desaturation of 3-phosphoethanolamine derivatives (requires molecular oxygen, cytochrome b5, NADPH+ + H+ for the synthesis)
  • There are 3 types of plasmalogens: choline, ethanolamine, serine
  • Most of the phospholipids in mitochondria are plasmalogens
  • Choline plasmalogen, the so-called platelet-activating factor (PAF), is a mediator of hypersensitivity, acute inflammatory reaction and anaphylactic shock. The IgE antigen stimulates its production. When PAF is released, platelet aggregation and serotonin secretion occur

Phosphatidylinositol[edit | edit source]

  • They contain inositol, a sugar alcohol
  • Part of cell membranes, where they significantly influence its permeability
  • A source of arachidonic acid, which is the starting material for the formation of eicosanoids
  • Important for the transport of fats by blood and lymph
  • After stimulation by a certain hormone, phosphatidylinositol-4,5-bisphosphate is split into diacylglycerol and inositol triphosphate - these substances act as an internal signal or second messenger

Links[edit | edit source]

Related articles[edit | edit source]

External links[edit | edit source]

Used literature[edit | edit source]

  • MATOUŠ, Bohuslav. Základy lékařské chemie a biochemie. 2010. edition. Galen, 2010. 0 pp. ISBN 978-80-7262-702-8.

  • MURRAY, Robert K. Harperova biochemie. 2. edition. H&H, 2002. 871 pp. ISBN 80-7319-013-3.