Mg"
Dihydroxyacetone phosphate
DPNH + H+ ^Χ
(α-Glycerophosphate λ
dehydrogenase)
I
DPN+
α-Glycerophosphoric acid
Lr-^2 Coenzyme A-activated
Choline (ethanolamine)
^-►ATP
( (Choline phosphokinase)
^-♦ADP
Phosphoryl-choline (-ethanolamine)
^CTP
MPhosphorylcholine cytidyl transferase
V Phosphorylethanolamine cytidyl transferase)
^* Pyrophosphate
Cytidine diphosphate-choline (-ethanolamine)
fatty acids
α-Phosphatidic acid
(Diglycerylkinase) ATP
(Phosphatidic acid
phosphatase)
D-1,2-Diglyceride
(+H3PO4)
Cytidine diphosphate diglyceride
Inositol
Phosphatidylinositol (+CMP)
CH
2 -
0
0
II
II
- 0- P- 0- P- OCH
2 CH
2 N(CH
3 )
3
0Plasmal
monoglyceride
Ceramide
(Phosphorylcholine
ceramide transferase)
Mn
++
Lecithin ( + CMP)
(phosphatidyl ethanolamine)
Choline plasmalogen (+CMP)
(ethanolamine plasmalogen)
Sphingomyelin (+CMP)
0>
to
p
>
i
a
FIG. 1. Enzyme systems that can synthesize phospholipids in vitro and possibly in vivo.