Lipids hydrolysis

PKC is a family of enzymes whose members play central roles in transducing information from external stimuli to cellular responses. Members of this family of serine/ threonine kinases respond to signals that cause lipid hydrolysis. PKC isozymes phosphorylate an abundance of substrates, leading to both short-term cellular responses such as regulation of membrane transport and long-term responses such as memory and learning. 

Members of the protein kinase C family promote signal transduction by catalyzing ATP-dependent protein phosphorylation [general EC number 2.7.1.37] in response to various signals that promote lipid hydrolysis. The primary activator is diacylglycerol. See also Cal-cium/Calmodulin-Dependent Protein Kinase... 

Finally, we conclude that toxic reactions in plant cells injured by ozone probably take place in the following sequence sulfhydryl oxidation, lipid hydrolysis, cellular leaking, lipid peroxidation, and then cellular collapse. 

The stomach also contains an active lipase that can hydrolyse triglycerides and so may start acting against the components of the lipidic formulations that are becoming more common. While this enzyme may be less abundant and less active than pancreatic lipase, there is sufficient activity to substantially initiate lipid hydrolysis (Carriere et al. 2000). 

Ptdlns 4,5-P2 is formed by a two-stage phosphorylation of Ptdlns, which is first phosphorylated at the 4-position of its inositol headgroup by a specific kinase to form Ptdlns 4-P this is in turn phosphorylated at the 5-position to give Ptdlns 4,5-P2, the substrate for receptor-mediated lipid hydrolysis. As well as the two kinases responsible for the stepwise phosphorylation of Ptdlns there are corresponding phospho-... 

Steatorrhea, the clinical result of insufficient intraluminal lipid hydrolysis, is the most important digestive malfunction in pancreatic exocrine insufficiency. As a rule, concomitant malabsorption of the lipid-soluble vitamins A, D, E, and K must be suspected in these patients. Naturally, potential differential diagnoses have to be considered in patients who present with steatorrhea (Table 26-1). The pivotal role of fat malabsorption in chronic pancreatitis is due to several interacting mechanisms ... 

Anderson, D.K., Saunders, R.D., Demediuk, P., Dugan, L.L., Braughler, J.M., Hall, E.D., Means, E.D. and Horrocks, L.A. (1985) Lipid hydrolysis and peroxidation in injured spinal cord partial protection with methylprednisolone or vitamin E and selenium, CNS Trauma 2, 257-267. 

For edible applications, lipids are often used intact. For such uses, the whole fats and oils are subjected to hydrogenation. For industrial uses, lipids are the feedstocks for free fatty acid production. When firmer fractions are needed for industrial applications, the free fatty acids obtained by lipid hydrolysis are subjected to... 

Lipases, developed by nature for the hydrolysis of fatty acyl ester bonds, have also been explored for the hydrolysis of fats and oils. However, because of issues of cost, stability, and productivity, they are not presently employed in industrial lipid hydrolysis. 

Until recently relatively little was known about the molecular basis of lipid hydrolysis. The first amino acid sequence of a triacylglycerol lipase was given by De Caro et al. (1981). As more sequence data became available, it was noted that lipases and esterases share a short consensus sequence, G-X-S-X-G (Boel et al., 1988 Datta et al., 1988 Antonian, 1988 Brenner, 1988). The role of the invariant serine at the center of this sequence was debated (Maraganore and Heinrikson, 1986). Some authors speculated about a lipid recognition site, others compared this pentapeptide to the sequence around the nucleophilic serine in serine proteinases. 

Fisher SK, Agranoff BW. Receptor activation and inositol lipid hydrolysis in neural tissues.. 1 Neurochem 1987 48 999-1017. 

Increasing the pH value of canned vegetables may lead to the formation of off-flavors (40). Hydrolysis of amides such as glutamine or asparagine at elevated pH values can result in formation of ammonia-like odors. Moreover, free fatty acids formed by lipid hydrolysis may oxidize to form rancid off-flavors. 

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