Phosphatidylcholine transfer protein from bovine liver contains highly unsaturated phosphatidylcholine species.
The phosphatidylcholine transfer protein (PC-TP) from bovine liver contains one molecule of non-covalently bound PC. In order to gain more insight into the physiological function of PC-TP, PC was extracted from bovine liver PC-TP and its molecular species composition identified by fast atom bombardment mass spectrometry. The prevailing molecular species were C18:0/C18:1-, C18:0/C18:2-, C18:0/C20:4-, C18:0/20:5- and C18:0/C22:5-PC accounting for 85% of the PC species present. This molecular species composition is not representative for what is present in bovine liver where these species account for 43% of the total PC content [Montfoort et al. (1971) Biochim. Biophys. Acta 231, 335-342]. Another striking observation is that PC species carrying a palmitoyl chain at the sn-1 position are nearly absent, despite these species being abundantly present in bovine liver. This study suggests that PC-TP could play a role in the metabolism of highly unsaturated, stearoyl-containing PC species.
Geijtenbeek
T B
TB
Centre for Biomembranes and Lipid Enzymology, Institute of Biomembranes, Utrecht University, The Netherlands.
Westerman
J
J
Heerma
W
W
Wirtz
K W
KW
D000727:Androgen-Binding Protein; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry*; D002417:Cattle; D002942:Circular Dichroism; D008099:Liver / Q000737:chemistry*; D010713:Phosphatidylcholines / Q000032:analysis*; D049294:Phospholipid Transfer Proteins; D016339:Spectrometry, Mass, Fast Atom Bombardment
D000727:Androgen-Binding Protein; D002352:Carrier Proteins; D010713:Phosphatidylcholines; D049294:Phospholipid Transfer Proteins