Sphingomyelinases
| Sphingomyelinases | ||
|---|---|---|
| Identifier | ||
| Gene name (s) | SMPD1 , SMPD2 , SMPD3 , SMPD4 , ENPP7 | |
| Enzyme classification | ||
| EC, category | 3.1.4.12 , phosphatase | |
| Response type | Hydrolysis of the phosphoric acid ester bond in sphingomyelin | |
| Substrate | Sphingomyelin + H 2 O | |
| Products | N-acylsphingosine + choline phosphate | |
| Occurrence | ||
| Parent taxon | Chordates | |
In Sphingomyelinases (short SMasen ) is enzymes . They catalyze the cleavage of the phosphodiester bond of sphingomyelin , which belongs to the group of sphingolipids . This creates ceramide and phosphorylcholine from sphingomyelin . Because of this function, the sphingomyelinases are also known as sphingomyelin phosphodiesterases .
So far , at least 5 different sphingomyelinases have been isolated in mammals , including humans: acid sphingomyelinase, alkaline sphingomyelinase and 3 neutral sphingomyelinases.
Acid sphingomyelinase ( gene name SMPD1 ) is of greater importance in medicine . A mutation in their coding gene leads to Niemann-Pick disease , in which a lack of the enzyme leads to the accumulation of sphingomyelin in the lysosomes . Conversely, in a small clinical study there was evidence of an association between enzyme overactivity and depression ; In vitro , the antidepressants amitriptyline and imipramine caused a reduction in enzyme activity .
The alkaline sphingomyelinase likely plays a role in the development of some cancers .
literature
- Markus Zumbansen (2001): Biochemical and molecular biological studies to characterize murine neutral sphingomyelinase in vitro and in vivo. (Dissertation, PDF version).
Individual evidence
- ↑ J. Kornhuber, A. Medlin et al .: High activity of acid sphingomyelinase in major depression. In: Journal of Neural Transmission , Volume 112, Number 11, November 2005, pp. 1583-1590, doi : 10.1007 / s00702-005-0374-5 .