Sphingolipids Sphingolipids
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Transcript Sphingolipids Sphingolipids
Chapter 17 Lipids
17.6
Sphingolipids
General, Organic, and Biological Chemistry
Copyright © 2010 Pearson Education, Inc.
1
Sphingosine
Sphingosine is an 18-carbon unsaturated amino alcohol.
Sphingosine
General, Organic, and Biological Chemistry
Copyright © 2010 Pearson Education, Inc.
2
Ceramides
In a ceramide,
the NH2 group in
sphingosine is
attached by an amide
bond to a fatty acid
General, Organic, and Biological Chemistry
Copyright © 2010 Pearson Education, Inc.
3
Sphingolipids
Sphingolipids
are similar to glycerophospholipids
contain sphingosine, a fatty acid, phosphate, and an
amino alcohol
General, Organic, and Biological Chemistry
Copyright © 2010 Pearson Education, Inc.
4
Sphingomyelin
Sphingomyelin
is a sphingolipid found in nerve cells
bonds the —OH of a ceramide to a phosphate ester
of choline
General, Organic, and Biological Chemistry
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5
Glycosphingolipids
Glycosphingolipids are
sphingolipids that contain monosaccharides attached
by a -glycosidic bond to the —OH group of ceramide
General, Organic, and Biological Chemistry
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6
Cerebrosides
Cerebrosides
contain galactose or glucose attached by a
-glycosidic bond to the —OH group of ceramide
are found in the brain and the myelin sheath
are important in cellular recognition and tissue
immunity
General, Organic, and Biological Chemistry
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Gangliosides
Gangliosides
are sphingolipids that contain chains of two to seven
monosaccharides
are important in neurons
are found on cell membrane surfaces
act as receptors for hormones, viruses, and drugs
can cause genetic diseases if they accumulate
General, Organic, and Biological Chemistry
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8
Gangliosides (continued)
GM2 is a ganglioside
that accumulates in Tay-Sachs disease when
hexoamidase A is defective
General, Organic, and Biological Chemistry
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9
Lipid Diseases (Lipidoses)
In many lipid diseases,
the deficiency of an enzyme causes
the accumulation of glycolipids
General, Organic, and Biological Chemistry
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10
Learning Check
Identify each as a
1) fatty acid
3) amino alcohol
5) glycosphingolipid
A.
B.
C.
D.
E.
2) triacylglycerol
4) glycerophospholipid
Glyceryl trioleate
Cephalin
Choline
Galactocerebroside
Palmitic acid
General, Organic, and Biological Chemistry
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Solution
Identify each as a
1) fatty acid
3) amino alcohol
5) glycosphingolipid
2) triacylglycerol
4) glycerophospholipid
A.
B.
C.
D.
E.
2)
4)
3)
5)
1)
Glyceryl trioleate
Cephalin
Choline
Galactocerebroside
Palmitic acid
General, Organic, and Biological Chemistry
triacylglycerol
glycerophospholipid
amino alcohol
glycosphingolipid
fatty acid
Copyright © 2010 Pearson Education, Inc.
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