Plant and Microbial Glycolipids

A major glycophosphoceramide from tobacco leaves, named PSL-I, has been characterized from the results of methylation, and periodate and chromium(vi) oxide oxidation analyses to have the structure (20). Six other novel 

Tsuboyama, F. Miki, M. Yoshida, Y. Ogura, and T. Miyatake, Clinica Chim. Acta, 

Kusumoto, I. Azuma, and Y. Mamamura, Bull. Chem. Soc. Japan, 

Yoshida and G. Kajimoto, Agrlc. and Biol. Chem. (Japan), 1977, 41, 1857. 

Lipopurothionins, petroleum ether-soluble lipid-protein complexes from the Gramineae sp., were converted to a petroleum ether-insoluble form on extraction with acetone. The only component of the acetone extract which was able to restore the solubility in petroleum ether was di-D-galactosyldi glyceride. 

Mono- and di-D-galactosyldiglycerides from numerous plant species have been separated from one another on a preparative scale. o-Galactose is the principal sugar present, although o-glucose occurs as a minor component of the glycolipids in a number of the plants. 

A novel glycolipid (12) isolated from the extreme thermoacidophile Bacillus acidocaldarius is a 2-acylamino-2-deoxy-j3-D-glucopyranosyl derivative of 1,2,3,4-tetrahydroxypentane linked to hopane (a pentacyclic triterpene) at C-29. Three other glycolipids possess a common structure (13) having the hydroxy-groups of their glycerol residues unsubstituted, or monoacylated, or diacylated. 

The general structural features of five families of polyacylated aa-trehalose 2-sulphates elaborated by Mycobacterium tuberculosis have been described. Biological acylation of the trehalose core does not appear to be very specific, but yields a family of sulpholipids the principal member has the structure (14). 

D-Glucose and myristic, palmitic, and stearic acids, as well as d-(—)-glyceric acid, are components of a glycolipid isolated from Nocardia caviae. Wheat-germ agglutinin and concanavalin A have been used in studies of the binding characteristics of mycoplasma cells and membranes.  

A pentaglycosyldiacylglycerol isolated from Acholeplasma modicum is composed of residues of D-galactose, D-glucose, and a heptose (2 2 1). A structure (15) 

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