Premium
Biosynthesis of glycosyl‐phosphatidylinositol lipids in Trypanosoma brucei: involvement of mannosyl‐phosphoryldolichol as the mannose donor.
Author(s) -
Me A. K.,
Mayor S.,
Schwarz R. T.
Publication year - 1990
Publication title -
the embo journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.484
H-Index - 392
eISSN - 1460-2075
pISSN - 0261-4189
DOI - 10.1002/j.1460-2075.1990.tb07873.x
Subject(s) - biology , trypanosoma brucei , mannose , glycosyl , biochemistry , biosynthesis , phosphatidylinositol , kinetoplastida , glycoprotein , immunology , gene , signal transduction , protozoal disease , malaria
Trypanosome variant surface glycoproteins (VSGs) exemplify a class of eukaryotic cell‐surface glycoproteins that rely on a covalently attached lipid, glycosyl‐phosphatidylinositol, for membrane attachment. The glycolipid anchor is acquired soon after translation of the polypeptide, apparently by replacement of a short sequence of carboxyl‐terminal amino acids with a precursor glycolipid. A candidate glycolipid precursor (P2) and a related glycolipid (P3) have been identified in polar lipid extracts from trypanosomes. Both lipids are glycosylphosphatidylinositol species containing a Man3GlcN core glycan indistinguishable from the backbone sequence of the VSG glycolipid anchor. We and others have recently described the cell‐free synthesis of P2, P3, and a spectrum of putative biosynthetic lipid intermediates using crude preparations of trypanosome membranes. In this paper we use these preparations to show that all three mannose residues in the glycosyl‐phosphatidylinositol glycan are derived from dolichol‐P‐mannose.