Sphingolipids sphingomyelin

In addition to phosphoglycerides, membranes from animal cells usually contain a second group of phospholipids, the sphingolipids. Sphingomyelin, which is representative of this group, has the structure... 

Fig. 2. Structures of (a) the sphingolipids sphingomyelin and galactocerebroside (b) cholesterol. R1 represents the hydrocarbon chain of fatty acids.

Ambident-ion sphingolipids (sphingomyelins) containing no sugar residues. 

The sphingolipid, sphingomyelin, is made by transferring choline from phosphatidylcholine to a ceramide (Figure 19.13). 

J. S. O Brien and G. Rouser, The Fatty Acid Composition of Brain Sphingolipids Sphingomyelin, Ceramide, Cerebroside, and Cerebroside Sulfate, J. Lipid Res. 5, 339-342 (1964). 

O Brien, J. S., and G. Rouser The fatty acid composition of brain sphingolipids sphingomyelin, ceramide, cerebroside and cerebroside sulfate. J. Lipid Res. 6, 339 (1964). 

Sphingolipids (ceramids, sphingomyelin, cerebrosides, sulfatides, gangliosides) and lipids with secondary amines produce blue spots on a white backgound (CAUTION benzidine is a carcinogen)... 

Figure 12.12 Sphingomyelins. Sphingomyelins are esters of a ceramide and phospho-ryl choline. However, similar compounds are ceramide-1-phosphoryl ethanolamines and phosphono forms of sphingolipids. Ceramides W-acyl-sphingosines) are amides of a long chain di- or trihydroxy base containing 12 to 22 carbon atoms, of which sphingosine (4-sphingenine) is the commonest, and a long chain fatty acid whose acyl chain is shown by R1. This may contain up to 26 carbon atoms.

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