Glycolipids structures

About 10-20% of all transmembrane proteins that are targeted to the ER and subsequently enter the secretory pathway are subject to post-translational modification with glycosylphosphatidyl-inositol (GPI). Proteins bearing the GPI anchor are involved in signal transduction, immune response, cancer cell invasion, and metastasis and the pathobiology of trypanosomal parasites. The structure of the GPI anchor has been analyzed for mammals, protozoa, and yeast. The general structure of the glycolipid structure is shown in Scheme 4. 

The opportunity to obtain molecular weight and structural information from very polar involatile materials by field desorption as described in this preliminary survey offers many advantages for the study of glycolipid structures. 

Heinz E. Plant glycolipids structure, isolation and analysis. In Advances in Lipid Methodology - Three. Christie WW, ed. 1996. Oily Press, Dundee, pp. 211-332... 

The following chapters in Advances in Lipid Methodology, Volume 3 (Cl) Chapter 3, Separation of phospholipid classes by high-performance liquid chromatography. W. W. Christie (C2) Chapter 6, Plant glycolipids Structure, isolation and analysis, E. Heinz. 

More recently, studies on Campylobacter jejuni have demonstrated how specific bacterial carbohydrate antigens can mimic the fine structure of human cell surface glycolipid structures and elicit autoimmune reactivity. Yuki et al.61 first identified that the lipooligosaccharide (LOS) of C. jejuni mimicked human G(M)1 ganglioside and subsequently extended these studies to demonstrate that specific single amino acid variants of the C. jejuni Cst-II sialyltransferase protein are responsible for the synthesis of LOS variants that in turn, mimic different... 

Tliis article focuses on the chemical structure, biosynthesis, and potential pathogenic role of the lipopolysaccharides (LPSs) from H. pylori. The structures of LPSs isolated from Helicobacter species found in nonhuman primates, which give rise to similar gastric symptoms in their respective hosts, are also described. LPSs are glycolipid structures carried by bacteria on their cell surfaces, which are actively involved in biochemical interactions between the bacterium and its host. ... 

The aim of this chapter is to cover general aspects of glycolipid structural diversity and more specifically the structural characterization and possible biological functions of glycosphingolipids from fungi and protozoa. 

Newer ionization methods such as FAB-MS and SIMS have been developed in which derivatization is unnecessary. With the aid of FAB-MS, it has been possible for the first time to obtain data on such structural parameters as molecular mass, homogene. /, sequences, composition branching and linkage. This method has been successfully applied to glycolipid structure analysis (30,31). 

Of the many analytical techniques now available to the lipid chemist, mass spectrometry (MS), is probably the one that has experienced the fastest growth in the last two decades. This is due both to the development of new techniques (gas and liquid chromatography combined with MS, soft-ionization MS, field desorption MS, atmospheric pressure MS etc.) and to the refinement of more traditional methods and their successful application to very complex problems, e.g. the elucidation of glycolipid structure, or the study of structures in lipid mixtures. Much progress has been made since the pioneering work of Ryhage and Stenhagen (1963) on fatty acid methyl esters. 

The structure-function relations of glycolipids in lipid membranes has been reviewed. This is a challenging endeavour which has mainly been faced through NMR spectroscopy and computational modelling, using model membranes such as micelles, bicelles, and bilayers. Glycolipid structure is rarely, if ever, a unique low-energy conformer, but an ensemble of dynamic states. ... 

Glycolipid Structure containing one or more saccharide units covalently attached to the primary hydroxyl group of iV-acyl sphingosine (ceramide), a C-18 amino alcohol. Those containing sialic acid are termed ganglio-sides. 

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