Triacylglycerol hydrolysis

The fatty acids released on triacylglycerol hydrolysis are transported to mitochondria and degraded to acetyl CoA, while the glycerol is carried to the liver for further metabolism. In the liver, glycerol is first phosphorylated by reaction with ATP. Oxidation by NAD+ then yields dihydroxyacetone phosphate (DHAP), which enters the carbohydrate metabolic pathway. We ll discuss this carbohydrate pathway in more detail in Section 29.5. 

The initial step to release fatty acids is triacylglycerol hydrolysis catalyzed by hormone-sensitive (HS) lipase. 

Young, S.C. and Hui, D.Y. 1999. Pancreatic lipase/colipase-mediated triacylglycerol hydrolysis is required for cholesterol transport from lipid emulsions to intestinal cells. Biochem. J. 339,... 

Immobilized lipases can also be used for triacylglycerol hydrolysis and hence the potential for production of cheese flavor concentrates. 

Higher temperatures clearly promote pigment adsorption and various catalytic reactions (peroxide decomposition, triacylglycerol hydrolysis). As a consequence, pigment and peroxide levels drop with increasing temperatures, whereas free fatty acids levels increase dramatically (Figure 23) because of increased triacylglycerol hydrolysis reactions. 

Glycerol is more reduced than the other gluconeogenic precursors, and it results primarily from triacylglycerol hydrolysis in adipose tissue. In liver and kidney, glycerol is converted to glycerol 3-phosphate by glycerol kinase ... 

The process of triacylglycerol hydrolysis is a complex phenomenon that involves at least three lipases, lipid droplet associated proteins, and FABPs, although other adipocyte lipases (i.e., triacylglycerol hydrolase) may play a role in basal lipolysis. The data at this time support the model that three lipases are the major contributors to adipocyte lipolysis. Complete hydrolysis of triacylglycerol involves the hydrolysis of three ester bonds to liberate three fatty acids and a glycerol moiety. ATGL catalyzes hydrolysis of the first... 

Belafi-Bako K, Dombi A, Szabo, Nagy E (1994), Triacylglycerol Hydrolysis by Lipase in a Flat Membrane Bioreactor , Biotec/ino/. Tech., 8,671-674. 

The fatty acids released on triacylglycerol hydrolysis are transported to mitochondria and degraded to acetyl CoA, while the glycerol is carried to... 

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