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Synthesis and evaluation of stimulatory properties of Sphingomonadaceae glycolipids

Department of Chemistry and Biochemistry, C100 BNSN, Brigham Young University, Provo, Utah 84602, USA.
Nature Chemical Biology (Impact Factor: 13.22). 07/2007; 3(9):559-564. DOI: 10.1038/nchembio.2007.19

ABSTRACT Glycosphingolipids (GSLs) from the Sphingomonadaceae family of bacteria have been reported to be potent stimulators of natural killer T cells. These glycolipids include mono-, tri- and tetraglycosylceramides. Here we have prepared the GSL-1 to GSL-4 series of glycolipids and tested their abilities to stimulate natural killer T cells. Among these glycolipids, only GSL-1 (Compound 1) is a potent stimulator. Using a series of synthetic diglycosylceramides, we show that oligoglycosylceramides from Sphingomonadaceae are not effectively truncated to GSL-1 in lysosomes in antigen-presenting cells, possibly because the higher-order GSLs are poor substrates for lysosomal acyltransfer enzymes.

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