Skip to main content
Biochemical Journal logoLink to Biochemical Journal
. 1994 May 1;299(Pt 3):741–746. doi: 10.1042/bj2990741

The fatty acids in unremodelled trypanosome glycosyl-phosphatidylinositols.

T L Doering 1, M S Pessin 1, G W Hart 1, D M Raben 1, P T Englund 1
PMCID: PMC1138083  PMID: 8192662

Abstract

Glycolipid A, the precursor of the glycosyl-phosphatidylinositol (GPI) anchor of the trypanosome variant surface glycoprotein, is constructed in two phases. First, the glycan is assembled on phosphatidylinositol (PI), yielding a glycolipid termed A'. Second, glycolipid A' undergoes fatty acid remodelling, by deacylation and reacylation, to become the dimyristoyl species glycolipid A. In this paper, we examine the fatty acid content of glycolipid A' and its cellular progenitors. A' contains exclusively stearate at the sn-1 position and a complex mixture of fatty acids (including 18:0, 18:1, 18:2, 20:4 and 22:6) at sn-2. Presumably these fatty acids derive from stearate-containing PI species which initially enter the biosynthetic pathway. We compared the diacylglycerol species from glycolipid A' with those from phosphatidylinositol to determine whether a subset of stearate-containing PIs is utilized for GPI biosynthesis. We found that the spectrum of stearate-containing diacylglycerols in PI is similar to that in A', although the proportions of each compound differ. Total PI in general was highly enriched in stearate-containing species. Differences in composition between glycosylated PI and total cellular PI may be due to the substrate specificity of the sugar transferase which initiates the GPI biosynthetic pathway. Alternatively, the species of PI present at the endoplasmic reticulum site of GPI biosynthesis may differ from those in total PI.

Full text

PDF
741

Images in this article

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bangs J. D., Hereld D., Krakow J. L., Hart G. W., Englund P. T. Rapid processing of the carboxyl terminus of a trypanosome variant surface glycoprotein. Proc Natl Acad Sci U S A. 1985 May;82(10):3207–3211. doi: 10.1073/pnas.82.10.3207. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bütikofer P., Kuypers F. A., Shackleton C., Brodbeck U., Stieger S. Molecular species analysis of the glycosylphosphatidylinositol anchor of Torpedo marmorata acetylcholinesterase. J Biol Chem. 1990 Nov 5;265(31):18983–18987. [PubMed] [Google Scholar]
  3. Caras I. W. Probing the signal for glycophosphatidylinositol anchor attachment using decay accelerating factor as a model system. Cell Biol Int Rep. 1991 Sep;15(9):815–826. doi: 10.1016/0309-1651(91)90035-h. [DOI] [PubMed] [Google Scholar]
  4. Clayton C. E., Mowatt M. R. The procyclic acidic repetitive proteins of Trypanosoma brucei. Purification and post-translational modification. J Biol Chem. 1989 Sep 5;264(25):15088–15093. [PubMed] [Google Scholar]
  5. Cross G. A. Glycolipid anchoring of plasma membrane proteins. Annu Rev Cell Biol. 1990;6:1–39. doi: 10.1146/annurev.cb.06.110190.000245. [DOI] [PubMed] [Google Scholar]
  6. Dethloff L. A., Gilmore L. B., Hook G. E. Separation of pulmonary surfactant phospholipids by high-performance liquid chromatography. J Chromatogr. 1986 Oct 31;382:79–87. doi: 10.1016/s0378-4347(00)83506-9. [DOI] [PubMed] [Google Scholar]
  7. Doering T. L., Masterson W. J., Englund P. T., Hart G. W. Biosynthesis of the glycosyl phosphatidylinositol membrane anchor of the trypanosome variant surface glycoprotein. Origin of the non-acetylated glucosamine. J Biol Chem. 1989 Jul 5;264(19):11168–11173. [PubMed] [Google Scholar]
  8. Doering T. L., Masterson W. J., Hart G. W., Englund P. T. Biosynthesis of glycosyl phosphatidylinositol membrane anchors. J Biol Chem. 1990 Jan 15;265(2):611–614. [PubMed] [Google Scholar]
  9. Doering T. L., Pessin M. S., Hoff E. F., Hart G. W., Raben D. M., Englund P. T. Trypanosome metabolism of myristate, the fatty acid required for the variant surface glycoprotein membrane anchor. J Biol Chem. 1993 May 5;268(13):9215–9222. [PubMed] [Google Scholar]
  10. Englund P. T. The structure and biosynthesis of glycosyl phosphatidylinositol protein anchors. Annu Rev Biochem. 1993;62:121–138. doi: 10.1146/annurev.bi.62.070193.001005. [DOI] [PubMed] [Google Scholar]
  11. Field M. C., Menon A. K., Cross G. A. A glycosylphosphatidylinositol protein anchor from procyclic stage Trypanosoma brucei: lipid structure and biosynthesis. EMBO J. 1991 Oct;10(10):2731–2739. doi: 10.1002/j.1460-2075.1991.tb07821.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Field M. C., Menon A. K., Cross G. A. Developmental variation of glycosylphosphatidylinositol membrane anchors in Trypanosoma brucei. Identification of a candidate biosynthetic precursor of the glycosylphosphatidylinositol anchor of the major procyclic stage surface glycoprotein. J Biol Chem. 1991 May 5;266(13):8392–8400. [PubMed] [Google Scholar]
  13. Hamm B., Schindler A., Mecke D., Duszenko M. Differentiation of Trypanosoma brucei bloodstream trypomastigotes from long slender to short stumpy-like forms in axenic culture. Mol Biochem Parasitol. 1990 Apr;40(1):13–22. doi: 10.1016/0166-6851(90)90075-w. [DOI] [PubMed] [Google Scholar]
  14. Krakow J. L., Doering T. L., Masterson W. J., Hart G. W., Englund P. T. A glycolipid from Trypanosoma brucei related to the variant surface glycoprotein membrane anchor. Mol Biochem Parasitol. 1989 Oct;36(3):263–270. doi: 10.1016/0166-6851(89)90174-6. [DOI] [PubMed] [Google Scholar]
  15. Krakow J. L., Hereld D., Bangs J. D., Hart G. W., Englund P. T. Identification of a glycolipid precursor of the Trypanosoma brucei variant surface glycoprotein. J Biol Chem. 1986 Sep 15;261(26):12147–12153. [PubMed] [Google Scholar]
  16. Lisanti M. P., Rodriguez-Boulan E., Saltiel A. R. Emerging functional roles for the glycosyl-phosphatidylinositol membrane protein anchor. J Membr Biol. 1990 Jul;117(1):1–10. doi: 10.1007/BF01871561. [DOI] [PubMed] [Google Scholar]
  17. Masterson W. J., Doering T. L., Hart G. W., Englund P. T. A novel pathway for glycan assembly: biosynthesis of the glycosyl-phosphatidylinositol anchor of the trypanosome variant surface glycoprotein. Cell. 1989 Mar 10;56(5):793–800. doi: 10.1016/0092-8674(89)90684-3. [DOI] [PubMed] [Google Scholar]
  18. Masterson W. J., Raper J., Doering T. L., Hart G. W., Englund P. T. Fatty acid remodeling: a novel reaction sequence in the biosynthesis of trypanosome glycosyl phosphatidylinositol membrane anchors. Cell. 1990 Jul 13;62(1):73–80. doi: 10.1016/0092-8674(90)90241-6. [DOI] [PubMed] [Google Scholar]
  19. Mayor S., Menon A. K., Cross G. A. Glycolipid precursors for the membrane anchor of Trypanosoma brucei variant surface glycoproteins. II. Lipid structures of phosphatidylinositol-specific phospholipase C sensitive and resistant glycolipids. J Biol Chem. 1990 Apr 15;265(11):6174–6181. [PubMed] [Google Scholar]
  20. Menon A. K., Mayor S., Ferguson M. A., Duszenko M., Cross G. A. Candidate glycophospholipid precursor for the glycosylphosphatidylinositol membrane anchor of Trypanosoma brucei variant surface glycoproteins. J Biol Chem. 1988 Feb 5;263(4):1970–1977. [PubMed] [Google Scholar]
  21. Menon A. K., Schwarz R. T., Mayor S., Cross G. A. Cell-free synthesis of glycosyl-phosphatidylinositol precursors for the glycolipid membrane anchor of Trypanosoma brucei variant surface glycoproteins. Structural characterization of putative biosynthetic intermediates. J Biol Chem. 1990 Jun 5;265(16):9033–9042. [PubMed] [Google Scholar]
  22. Patnaik P. K., Field M. C., Menon A. K., Cross G. A., Yee M. C., Bütikofer P. Molecular species analysis of phospholipids from Trypanosoma brucei bloodstream and procyclic forms. Mol Biochem Parasitol. 1993 Mar;58(1):97–105. doi: 10.1016/0166-6851(93)90094-e. [DOI] [PubMed] [Google Scholar]
  23. Pessin M. S., Raben D. M. Molecular species analysis of 1,2-diglycerides stimulated by alpha-thrombin in cultured fibroblasts. J Biol Chem. 1989 May 25;264(15):8729–8738. [PubMed] [Google Scholar]
  24. Roditi I., Schwarz H., Pearson T. W., Beecroft R. P., Liu M. K., Richardson J. P., Bühring H. J., Pleiss J., Bülow R., Williams R. O. Procyclin gene expression and loss of the variant surface glycoprotein during differentiation of Trypanosoma brucei. J Cell Biol. 1989 Feb;108(2):737–746. doi: 10.1083/jcb.108.2.737. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Udenfriend S., Micanovic R., Kodukula K. Structural requirements of a nascent protein for processing to a PI-G anchored form: studies in intact cells and cell-free systems. Cell Biol Int Rep. 1991 Sep;15(9):739–759. doi: 10.1016/0309-1651(91)90030-m. [DOI] [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES