Catalysis of the reaction: H(2)O + sphingomyelin = ceramide + choline phosphate + H(+)
1. EC 3.1.4.122. RHEA: 19253
3. KEGG REACTION: R02541
4. MetaCyc SPHINGOMYELIN-PHOSPHODIESTERASE-RXN5. Reactome: R-HSA-1605797 "Sphingomyelin phosphodiesterase (SMPD1) hydrolyses sphingomyelin to ceramide (lysosome)"
6. Reactome: R-HSA-1606273 "Sphingomyelin phosphodiesterase 2 and 3 (SMPD2 and 3) hydrolyse sphingomyelin to ceramide (plasma membrane)"
7. Reactome: R-HSA-1606288 "Sphingomyelin phosphodiesterase 4 (SMPD4) hydrolyses sphingomyelin to ceramide (ER membrane)"
8. Reactome: R-HSA-1640164 "Ectonucleotide pyrophosphatase/phosphodiesterase 7 (ENPP7) hydrolyses sphingomyelin"
9. Reactome: R-HSA-193706 "Production of ceramide which can activate JNK and other targets"