Synthesis of covalently immobilized phospholipid analogues

Simple and complex lipids: their occurrence, chemistry, and biochemistry

“…spectroscopy) for studies of the stereospecificity of phospholipase D.lS5 A procedure has been described for linking the water-soluble drug ' methotrexate ' and related compounds covalently to phosphatidylethanolamines, as a means of introducing them into lipid bilayers.16s For studies of the recognition of model membranes by the immune system, an analogue of phosphatidylethanolamine was synthesized in which the lipid was linked to a peptide (spacer molecule), which was in turn bound at the N-terminus to fluorescein (the hapten In a similar way, a sulphonylazide moiety was introduced into the polar head-group of phosphatidylethanolamine (to enable a photo-activable interaction with proteins),168 an N-hydroxysuccinimide ester was prepared (to bind to compounds that have a free amino-gro~p),'~~ and a procedure was described for synthesizing phosphatidylethanolamine in such a manner that it was bound to AH-SepharoseTM (for use in the affinity purification of enzymes that are involved in the metabolism of phospholipids). 170 By experiments in vitro, it was shown that the relatively high concentrations of molecular species of phosphatidylethanolamine that contain penta-and hexa-enoic fatty acids in Ehrlich ascites tumour cells are largely a consequence of the specificity of the ethanolaminephosphotransferase. 171 In Escherichia coli there appears to be a metabolic cycle in which the fatty acids at position 1 of phosphatidylethanolamine are utilized for some purpose, while the resulting 1 -1ysophospholipid is re-acylated by an acyl-carrier-protein-dependent acyltransferase.…”