Harpers

ATPADPNAD + NADH + H +H 2 COHH 2 COHH 2 COHHOCHHOCHCOGlycolysisH 2 COHGlycerolGLYCEROL KINASEH 2 C O Psn-Glycerol3-phosphateGLYCEROL-3-PHOSPHATEDEHYDROGENASEH 2 C O PDihydroxyacetonephosphateAcyl-CoA (mainly saturated)2GLYCEROL-3-PHOSPHATEACYLTRANSFERASEH 2 COCoAOC R 1R 2H 2 C OHC O C HO H 2 C OH2-MonoacylglycerolHO CHH 2 C OP1-Acylglycerol-3-phosphate(lysophosphatidate)Acyl-CoA (usually unsaturated)Acyl-CoAMONOACYLGLYCEROLACYLTRANSFERASE(INTESTINE)CoA1R 2COH 2 CCCoAOO C R 1H1-ACYLGLYCEROL-3-PHOSPHATEACYLTRANSFERASEOH 2 CO1,2-Diacylglycerolphosphate(phosphatidate)PCholineH 2 OCTPATPCHOLINEKINASEPHOSPHATIDATEPHOSPHOHYDROLASECDP-DGSYNTHASEP 1PP 1ADPPhosphocholineCTPCTP:PHOSPHOCHOLINECYTIDYLTRANSFERASER 2COH 2 COO C HH 2 COH1,2-DiacylglycerolOC R 1R 2COH 2 CO CH 2 COHOC R 1O P PCytidineCDP-diacylglycerolCardiolipinPP 1H 2 CCDP-cholineAcyl-CoAInositolCDP-CHOLINE:DIACYLGLYCEROLPHOSPHOCHOLINETRANSFERASEDIACYLGLYCEROLACYLTRANSFERASEPHOSPHATIDYL-INOSITOL SYNTHASECMPOCoAOCMPATPOKINASEADPOOC R 1H 2 COC R 1H 2 COC R 1H 2 COC R 1R 2 C O C HO H2C O PCholineR 2COOCHH2C O C R3TriacyglycerolPhosphatidylcholinePHOSPHATIDYLETHANOLAMINEN-METHYLTRANSFERASEPhosphatidylethanolamineCO2PhosphatidylserineO(–CH 3 ) 3SerineR 2EthanolamineCOOCHH2CO PInositolPhosphatidylinositolFigure 24–2 . Biosynthesis of triacylglycerol and phospholipids.(1 , Monoacylglycerol pathway; 2 , glycerol phosphate pathway.)Phosphatidylethanolamine may be formed from ethanolamine by apathway similar to that shown for the formation of phosphatidylcholinefrom choline.R 2 C O C HO H2C O P Inositol PPhosphatidylinositol 4-phosphateATPADPKINASEH 2 COC R 1R 2 C O C HO H2C O P Inositol PPPhosphatidylinositol 4,5-bisphosphateO