Facilitated phospholipid flip-flop using synthetic steroid-derived translocases
Timothy N Lambert1, J Middleton Boon, Bradley D Smith
1Department of Chemistry and Biochemistry and Walther Cancer Research Center, University of Notre Dame, Notre Dame, Indiana 46556, USA.
Abstract:
Cholate esters with phenylurea groups at the 7alpha- and 12alpha-positions are highly effective promoters of phosphatidylcholine translocation across vesicle and cell membranes. The urea groups are essential for strong binding of the highly polar phosphate portion of the phosphocholine headgroup and apparently cannot be replaced by simple amide, alcohol, or amine moieties. NMR and UV studies show that these synthetic translocases have very weak affinity for phosphatidylethanolamine and phosphatidylserine.
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