{{Short description|Class of enzymes}} {{Infobox enzyme | Name = Sphingomyelin phosphodiesterase D | EC_number = 3.1.4.41 | CAS_number = 54992-31-3 | GO_code = | image = | width = | caption = Crystal structure of Sphingomyelin phosphodiesterase D, class II phospholipase D from the recluse spider Loxosceles intermedia (from PDB entry {{PDB2|3RLH}} <ref>{{cite journal | vauthors = de Giuseppe PO, Ullah A, Silva DT, Gremski LH, Wille AC, Chaves Moreira D, Ribeiro AS, Chaim OM, Murakami MT, Veiga SS, Arni RK | title = Structure of a novel class II phospholipase D: catalytic cleft is modified by a disulphide bridge | journal = Biochemical and Biophysical Research Communications | volume = 409 | issue = 4 | pages = 622–7 | date = June 2011 | pmid = 21616057 | doi = 10.1016/j.bbrc.2011.05.053 | hdl = 11449/72498 | hdl-access = free }}</ref>) }} '''Sphingomyelin phosphodiesterase D''' (EC 3.1.4.41, '''sphingomyelinase D''') is an enzyme of the sphingomyelin phosphodiesterase family with systematic name '''sphingomyelin ceramide-phosphohydrolase'''.<ref>{{cite journal | vauthors = Carne HR, Onon EO | title = Action of ''Corynebacterium ovis'' exotoxin on endothelial cells of blood vessels | journal = Nature | volume = 271 | issue = 5642 | pages = 246–8 | date = January 1978 | pmid = 622164 | doi = 10.1038/271246a0 | bibcode = 1978Natur.271..246C }}</ref><ref>{{cite journal | vauthors = Soucek A, Michalec C, Soucková A | title = Identification and characterization of a new enzyme of the group "phospholipase D" isolated from Corynebacterium ovis | journal = Biochimica et Biophysica Acta (BBA) - Enzymology | volume = 227 | issue = 1 | pages = 116–28 | date = January 1971 | pmid = 5543581 | doi = 10.1016/0005-2744(71)90173-2 }}</ref> These enzymes catalyse the hydrolysis of sphingomyelin, resulting in the formation of ceramide 1-phosphate and choline: : sphingomyelin + H<sub>2</sub>O <math>\rightleftharpoons</math> ceramide 1-phosphate + choline or the hydrolysis of 2-lysophosphatidylcholine to give choline and 2-lysophosphatidate. Sphingomyelin phosphodiesterase D activity is shared by enzymes with a wider substrate range, classified as phospholipases D or lipophosphodiesterase II {{EC number|3.1.4.4}}.<ref>{{cite journal | vauthors = Murakami MT, Fernandes-Pedrosa MF, Tambourgi DV, Arni RK | title = Structural basis for metal ion coordination and the catalytic mechanism of sphingomyelinases D | journal = The Journal of Biological Chemistry | volume = 280 | issue = 14 | pages = 13658–64 | date = April 2005 | pmid = 15654080 | doi = 10.1074/jbc.M412437200 | doi-access = free }}</ref> Sphingomyelinases D are produced by some spiders in their venoms, specifically the brown recluse (''Loxosceles reclusa''),<ref>{{cite book |last1=Vetter |first1=Richard S. |title=The Brown Recluse Spider |date=2015 |publisher=Cornell University Press |location=Ithaca, New York |isbn=978-0-8014-7985-4 |page=58 |edition=1st |url=https://www.cornellpress.cornell.edu/book/9780801479854/the-brown-recluse-spider/#bookTabs=1 |accessdate=1 January 2020}}</ref> by arthropods such as ticks, or pathogenic bacteria and fungi. Pathogenicity is expressed through different mechanisms, such as membrane destabilization, cell penetration, inflammation of the lungs and cutaneous lesions, common following brown recluse spider bites.
== See also == * Sphingomyelin phosphodiesterase
== References == {{reflist}}
== External links == * {{MeshName|Sphingomyelin+phosphodiesterase+D}} * http://www.arachnoserver.org/toxincard.html?id=138 {{Esterases}} {{Enzymes}} {{Portal bar|Biology|border=no}}
Category:EC 3.1.4