C20-sphingosine

Sonnino, S., Chigorno, V. (2000) Ganghoside molecular species containing C18- and C20-sphingosine in mamma-han nervous tissues and neuronal cell cultures. Biochimica et Biophysica Acta, 1469,63-77. 

Previous biochemical studies have shown that the LCB of brain gangliosides has either 18 or 20 carbons (i.e., C18- or C20-sphingosine). The C20-sphingosine (C20-LCB species) is present in significant amounts only in the central nervous system (19-22). Its content increases significantly throughout life in rodents and in human (23-25). Because of its characteristic brain specificity and the dramatic increase during the course of life, the... 

From the sea anemone M. senile was isolated j3-glucopyranosyl-( 1 - l)-ceramide, the structure of which was determined by mass spectrometry, H-n.m.r. spectroscopy, and chemical splitting. The major sphingosine in the cerebroside is a new base containing two double bonds and branching at one double bond, namely, 2-amino-D-eryf/jro-l,3-dihydroxy-9-methyl-( , E)-octadeca-4,8-diene. The major fatty acids are Ci6 0 and C20 o a-hydroxy acids.133... 

Schmidt and Zimmerman [44] have prepared C20-eryfAro-sphingosine (44) from 4,6-0-benzylidene-D-galactose. This was cleaved with periodate to give the D-threose derivative (41) which, with a Wittig reagent in the presence of lithium bromide, gave predominantly the /raw-olefin (42). This was converted via the trifluoromethane... 

Another example is the content of caulerpicin in the green alga Caulerpa racemosa. Originally the toxin was isolated from a Philippine collection (147-148). The toxin was a mixture of sphinganine derived ceramides (149) with C18 (32%), C20 (2%), C22 (6%), C24 (35%), and C26 (25%) saturated fatty acid residues. However, a sample of the same species collected off Sri Lanka contained a different mixture (150). The Sri Lankan sample was a mixture of N-acylsphingosines (sphingosine= A4-... 

Sphingomyelin consists of a ceramide unit linked at position 1 to phosphorylcholine, and it is found as a major component of the complex lipids of all animal tissues, but is not present in plants or microorganisms. It resembles phosphatidylcholine in many of its physical properties, and can apparently substitute in part for this in membranes. Sphingosine is usually the most abundant Iong-chain base constituent, together with sphinganine and C20 homologues. 

The long-chain base of brain gangliosides from cold-blooded animals mainly is C g-sphingosine, the C20-homolog content being much lower as compared to that in mammals (Avrova and Zabelinskii, 1971). 

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