title: The bovine seminal plasma protein PDC-109 extracts phosphorylcholine-containing lipids from the outer membrane leaflet.
abstract: The bovine seminal plasma protein PDC-109 modulates the maturation of bull sperm cells by removing lipids, mainly phosphatidylcholine and cholesterol, from their cellular membrane. Here, we have characterized the process of extraction of endogenous phospholipids and of their respective analogues. By measuring the PDC-109-mediated release of fluorescent phospholipid analogues from lipid vesicles and from biological membranes (human erythrocytes, bovine epididymal sperm cells), we showed that PDC-109 extracts phospholipids with a phosphorylcholine headgroup mainly from the outer leaflet of these membranes. The ability of PDC-109 to extract endogenous phospholipids from epididymal sperm cells was followed by mass spectrometry, which allowed us to characterize the fatty acid pattern of the released lipids. From these cells, PDC-109 extracted phosphatidylcholine and sphingomyelin that contained an enrichment of mono- and di-unsaturated fatty acids as well as short-chain and lyso-phosphatidylcholine species. Based on the results, a model explaining the phospholipid specificity of PDC-109-mediated lipid release is presented.
authors.affiliation: Institute of Biology, Humboldt University of Berlin, Berlin, Germany.
authors.forename: Astrid
authors.initials: A
authors.lastname: Tannert
authors.forename: Anke
authors.initials: A
authors.lastname: Kurz
authors.forename: Karl-Rudolf
authors.initials: KR
authors.lastname: Erlemann
authors.forename: Karin
authors.initials: K
authors.lastname: Müller
authors.forename: Andreas
authors.initials: A
authors.lastname: Herrmann
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schiller
authors.forename: Edda
authors.initials: E
authors.lastname: Töpfer-Petersen
authors.forename: Puttaswamy
authors.initials: P
authors.lastname: Manjunath
authors.forename: Peter
authors.initials: P
authors.lastname: Müller
mesh_terms: D000818:Animals; D002417:Cattle; D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism; D002478:Cells, Cultured; D006801:Humans; D008081:Liposomes / Q000737:chemistry*; D008297:Male; D008563:Membrane Lipids / Q000737:chemistry* / Q000378:metabolism; D010767:Phosphorylcholine / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding; D029607:Seminal Vesicle Secretory Proteins / Q000737:chemistry* / Q000378:metabolism*; D013094:Spermatozoa / Q000737:chemistry* / Q000378:metabolism
chemical_list: D008081:Liposomes; D008563:Membrane Lipids; D029607:Seminal Vesicle Secretory Proteins; C424303:seminal vesicle secretory protein 109, Bos taurus; D010767:Phosphorylcholine