Mammalian lysophospholipases

Wang, A.J., Dennis, E.A. 1999. Mammalian lysophospholipases. Biochim. Biophys. Acta/Mol. Cell Biol. Lipids 1439 1-16. 

Phospholipase D - Phospholipase D cleaves the phosphoester bond between phosphatidic acid and the alcoholic moiety of different phospholipids. It is widely present in plants but few reports have indicated the presence of phospholipase D in mammalian tissues.1 In rat brain a phospholipase D that converts phosphatidylcholine to phosphatidic acid has been studied.100 Eosinophils also contain a phospholipase D activity.101 A lysophospholipase D activity seems to have an absolute specificity for 1-alkyl-sn-glycero-3-phosphoethanolamine or -choline102 and it is present in microsomes of rat brain,103 kidney, intestine, lung, testes and liver.104 A recent report indicates that a phospholipase D might be activated in human and rabbit neutrophils stimulated with chemotactlc peptides.105 This activity would induce a net loss of phosphatidylinositol with a net gain in phosphatidic acid. However, this activity has not yet been characterized and its function is not known. 

In contrast to phospholipase B, lysophospholipases are widely distributed and are found in microorganisms, bee venoms and mammalian tissues. Many of them have limited activity towards intact phospholipids. In beef liver, two distinct lysophospholipases have been found - localized in the mitochondrial and microsomal fractions. 

The function(s) of lysophospholipases is unclear. It has been suggested that in mammalian tissues they help to prevent the build-up of lytic lysophospholipids. 

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