Editing Phospholipase

{{Short description|Class of enzymes that cleave phospholipids}}
[[Image:Phospholipases2.svg|thumb|right|Phospholipase cleavage sites. An enzyme that displays both PLA<sub>1</sub> and PLA<sub>2</sub> activities is called a [[phospholipase B]].]]

A '''phospholipase''' is an enzyme that hydrolyzes [[phospholipid]]s<ref>{{DorlandsDict|six/000081983|phospholipase}}</ref> into [[fatty acid]]s and other [[lipophilic]] substances. There are four major classes, termed A, B, C, and D, which are distinguished by the type of reaction which they catalyze:

*Phospholipase A
**[[Phospholipase A1|Phospholipase A<sub>1</sub>]] – cleaves the ''sn''-1 [[Acyl group|acyl chain]] (where ''sn'' refers to [[Glycerophospholipid#Nomenclature and stereochemistry|stereospecific numbering]]).
**[[Phospholipase A2|Phospholipase A<sub>2</sub>]] – cleaves the ''sn''-2 [[Acyl group|acyl chain]], releasing [[arachidonic acid]].
*[[Phospholipase B]] – cleaves both ''sn''-1 and ''sn''-2 [[Acyl group|acyl chain]]s; this enzyme is also known as a lysophospholipase.
*[[Phospholipase C]] – cleaves before the phosphate, releasing [[diglyceride|diacylglycerol]] and a phosphate-containing head group. [[Phospholipase C|PLC]]s play a central role in [[signal transduction]], releasing the [[second messenger]] [[inositol triphosphate]].
*[[Phospholipase D]] – cleaves after the phosphate, releasing [[phosphatidic acid]] and an alcohol.

Types C and D are considered [[phosphodiesterase]]s.

[[Endothelial lipase]] is primarily a phospholipase.<ref name="pmid28540715">{{cite journal | vauthors=Yu JE, Han SY, Wolfson B, Zhou Q | title=The role of endothelial lipase in lipid metabolism, inflammation, and cancer| journal= [[Histology and Histopathology]] | volume=33 | issue=1 | pages=1–10 | year=2018 | doi=10.14670/HH-11-905 | pmc =5858721  | pmid = 28540715 }}</ref>

Phospholipase A<sub>2</sub> acts on the intact lecithin molecule and hydrolyzes the fatty acid esterified to the second carbon atom. The resulting products are [[lysolecithin]] and a fatty acid. Phospholipase A<sub>2</sub> is an enzyme present in the venom of [[bee]]s, [[blennies]] and [[Viperidae|viper snakes]].<ref>D. M. Vasudevan & S. Sreekumari, ''Textbook of Biochemistry'' (5th ed.)</ref>

==See also==
*[[Patatin-like phospholipase]]
*[[Infantile neuroaxonal dystrophy]]

==References==
{{reflist}}

==Further reading==
* Tappia, Paramjit S. & Dhalla, Naranjan S. (Editors): ''Phospholipases in Health and Disease.'' Springer, 2014. {{ISBN|978-1-4939-0463-1}} [Print]; {{ISBN|978-1-4939-0464-8}} [eBook]

==External links==
{{Commons category|Phospholipases}}
*{{MeshName|Phospholipases}}

{{Esterases}}
{{Lipid signaling}}

[[Category:Peripheral membrane proteins]]
[[Category:Cell signaling]]
[[Category:Hydrolases]]


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