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The glycerol-3-phosphate or dihydroxyacetone phosphate and fatty acyl-CoA esters produce the triacylglycerols.The process involves the use of three fatty acids.

Dihydroxyacetone phosphate is first converted top either glycerol-3-phosphate by glycerol-3-phosphate dehydrogenase or acyl-dihydroxyacetone phosphate by

dihydroxyacetone phosphate acyltransferase. Both of these products are then converted to lysophosphatidic acid by glycerol-3-phosphate acyltransferase and acyl-dihydroxyacetone phosphate reductase, respectively.

$$\begin{gathered} Dihydroxyacetonephosphate+NADH+H^{+}\underset{Gycerol-3-phosphatedehydrogenase}{→}Gycerol-3-phosphate+NA{D}^{+} \\ Dihydroxyacetonephosphate+fattyacyl-CoAester\underset{}{→}Acyl-dihydroxyacetonephosphate+HSCoA \\ Gycerol-3-phosphate+NADH+H^{+}\underset{glycerol-3-phosphateacyltransferase}{→}Lysophosphatidicacid+HSCoA \\ Acyl-dihydroxyacetonephosphate+NADH+H^{+}\underset{Acyl-dihydroxyacetonephosphatereductase}{→}Lysophosphatidicacid+NA{D}^{+} \end{gathered}$$

Lysophosphatidic acid is converted to phosphatidic acid by 1-acylglycerol-3-phosphate acyltransferase, which is then converted to diacylglycerol by phosphatidic acid phosphatase. The diacylglycerol can also be produced from a reaction between 2-monoacylglycerol and a fatty acyl-CoA ester by 2-monoacylglycerol acyltransferase.

$$\begin{gathered} Lipophosphatidicacid+fatty-acylCoAester\underset{1acylglycerol-3phosphateacyltransferase}{→}Phosphatidicacid+HSCoA \\ Phosphatidicacid\underset{Phosphatidicacidphosphatase}{→}Diacylglycerol+P_i \\ 2-Monoacylglycerol+fatty-acylCoAester\underset{2-Monoacylglycerolacyltransferase}{→}Diacylglycerol+HSCoA \\ Diacylglycerolacid+fatty-acylCoAester\underset{Diacylglycerolacyltransferase}{→}Tricylglycerol+HSCoA \end{gathered}$$