Structure & Function - Lipids Flashcards
Ceramide
sphingosine + fatty acid
Cerebroside
sphingosine + fatty acid + monosaccharide
Sulfatide
Sphingosine + fatty acid + monosaccharide-sulfate
Globoside
Sphingosine + fatty acid + oligosaccharide
Ganglioside
Spingosine + fatty acid + oligosaccharide(contains NANA)
NANA
n-acetylmeuraminic acid
Cholesterol
(amphipathic) Has a free hydroxyl group
Cholesterol ester
(hydrophobic) cholesterol + fatty acid
Phosphatidylcholine(lecithin)
glycerol + 2 fatty acids + phosphate + choline
most abundant
present in outer and inner leaflet
phosphatidylethanolamine
glycerol + 2 fatty acids + phosphate + ethanol amine inner leaflet (with phophatidylserine)
phosphatidylinositol
glycerol + 2 fatty acids + inositol
inner leaflet
phosphorylated to PIP2 –> hydrolyzed to –> IP3 and DAG
(G-protein pathway)
triacylglycerol
(hydrophobic) glycerol + 3 fatty acids
Glycerophospholipids
phosphatidylcholine phosphatidylethanolamine phosphatidylserine phosphatidylinositil DPPC (synthetic phophatidylcholine)
Sphingophospholipid
sphingomyelin
phospholipids
surfactant, low in premature neonates - respiratory distress syndrome(RDS).
glycerophospholipids
sphingophospholipid
Glycolipids
amphipathic, sphingosine and fatty acid - two polar tails, carbohydrate group - polar head. Present in the outer leaflet. Part of the glycocalyx. cerebrosides sulfatide globoside ganglioside
Complex lipids
classified based on the non-lipid component:
phospholipids
glycolipids
Functions of Cholesterol
cell/plasma membrane
bile acid/bile salt synthesis
steroid hormones
vitamin D
Composition of myelin sheath
gangliosides cerebrosides glycolipids sulfatide spingomyelin sphingophospholipid cholesterol
Lecithin-Sphingomyelin ratio (L/S ratio)
measured in amniotic fluid
determine fetal lung maturity
>2 low risk RDS
<1.5 high risk RDS (common before 32 wks)
artificial (containing DPPC) can be delivered to mother
Cardiolipin
glycerophospholipid
contains two molecules of phosphatidic acid linked by glycerol.
inner mitochondrial membrane
Plasmalogens and Platelet activating factor (PAF)
phospholipids w/ether linkages (instead of ester) at C-1 of glycerol.
ether: R-O-R’
ester: R-C(=O)-OR’
eicosanoids
grieved from 20-C PUFA arachidonic acid
two classes: prostaglandins and leukotrienes
Prostoglandins
mediators of inflammation
cause pain, fever, redness
Thromboxane causes platelet aggregation
Leukotrienes
mediators of allergic response
bronchoconstriction, itching
essential fatty acids
humans cannot add a double bond after C-9
linoleic (6) and linolenic (3)
deficiency: scaly dermatitis, rough/dry skin, loss of hair
