Lipases phospholipase

Carboxylesterase Arylesterase Triacylglycerol lipase Phospholipase A2 Lysophospholipase Acetylesterase Acetylcholinesterase Cholinesterase... 

It is dear that the interconnection between the activities of the different lipolytic enzymes, where the first enzyme modifies the physicochemical state of the lipid substrate in such a way that it becomes available to another enzyme, is not only of prime importance for lipid digestion, but also results in a broad synergism between gastric lipase, colipase, pancreatic lipase, phospholipase As. calcium, caiboxylester Lipase, bite salts, and substrate interraecK tes [55,62-64]. 

Thus, description of a simple change of fatty acid at the primary position required frequent changes of configuration prefixes. Also, the R/S system, like the older D/L one, did not account for the stereospecificity of the acylglycerol derivatives toward lipases (phospholipase A2 in particular). Finally, nonrandom distribution of fatty acids in natural or synthetic enantiomeric acylglycerols could not be systematically correlated by reference to either the R/S or D/L configuration. 

Scow, R.D., Egelrud, T. 1976. Hydrolysis of chylomicron phosphatidyl choline in vitro by lipoprotein lipase, phospholipase A2 and phospholipase C. Biochim. Biophys. Acta 431, 538-549. 

Salivary lipase, lingual lipase, phospholipase, and pregastrie lipase all seem to have the same desirable hydrolytic effect. 

H. S. Hendrickson, Fluorescence-based assays of lipases, phospholipases, and... 

This enzyme (triacylglycerol acyl-hydrolase) has a molecular mass of approximately 42 kDa (Hide, Chan, and Li 1992) and a short half-life of about 1-3 h in dogs. Pancreatic lipase is secreted in its active form, and this activity is enhanced by colipase and bile salts the enzyme hydrolyzes triglycerides to monoglycerides. Other lipases— phospholipase a, phospholipase b, and cholesterol ester hydrolase—are also secreted by the pancreas. 

Hendrickson, H. S. 1994. Fluorescence-Based Assays of Lipases, Phospholipases, and Other Lipolytic Enzymes. Analytical Biochemistry 219 8. 

VLDL are assembled in the liver, and contain newly synthesized triacylglycerol, cholesterol and cholesteryl esters and phospholipids as well as lipids from chylomicron remnants. These lipids are taken up by peripheral tissues which have cell-surface lipoprotein lipase, phospholipase and cholesterol esterase. 

Lipase, phospholipase and lipoxygenase are the enzymes primarily responsible for poor-quality rice bran oil. They are activated during the bran removal process (Vetrimani et al., 1992 Takano, 1993), and can cause the rate of free fatty acid (FFA) formation to be as high as 5-7% per day (Nasirullah et al., 1989). Thus, inactivation of lipases is important for producing high-quality rice bran oil. The quality of rice bran oil is inversely related to the level of FFA, and this must be kept low if the oil is to be edible and acceptable in frying applications. However, the removal of FFA is not a simple process and is accompanied by the loss of important antioxidants (Krishna et ai, 2001). This loss must be kept to a minimum if rice bran oil is to be used as a functional food component. 

Several metabolic pathways may produce 2-AG. The principal route is Ca -dependent and is mediated by two enzymes, phospholipase C and diacylglycerol lipase. Phospholipase C hydrolyzes an arachidonic acid-containing membrane phospholipid (e.g., phosphati-dylinositol) and produces an arachidonic acid-containing diacylglycerol. Then, 2-AG is produced from this diacylglycerol by the action of diacylglycerol lipase. 

Research on structural modification of PLs to achieve the aforementioned nutritional and functional properties has increased prominently. The structural modification of PLs can be done enzymatically using phospholipases and lipases. Phospholipase A (PLAj) cleaves the fatty acid at the sn-l position, while Phospholipase A (PLA ) cleaves the fatty acid at the sn-2 position. Phospholipase C (PLC) hydrolyses the phosphodiester bond between the glycerol backbone and phosphate. On the other hand, phospholipase D (PLD) hydrolyses the phosphodiester bond between the phosphate and the head group. Lipases can also be used to modify the fatty acid composition at sn-l and sn-2 positions of phospholipids. Guo and co-workers (2005) and Nieuwenhuyzen and Thomas (2008) have provided a detailed review on enzymatic modification of phospholipids for functional applications and human nutrition. 

Lipases, phospholipases, cutinases, membrane-associated proteins, and coupled enzymes have specific activation and/or stabilization needs, which must be met for efficient functioning. Whole-cell systems require biocompatible protocols, which can support long-term viability. 

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