|
type |
Journal Article |
authors |
Van Veldhoven, P. P.; Mannaerts, G. P. |
title |
Sphinganine 1-phosphate metabolism in cultured skin fibroblasts: evidence for the existence of a sphingosine phosphatase |
journal |
Biochem J |
Activity |
4.1.2.27 |
ui |
94250216 |
year |
(1994) |
volume |
299 |
number |
Pt 3 |
pages |
597-601. |
| |
keywords |
Adrenoleukodystrophy/enzymology/metabolism |
abstract |
On addition of [4,5-3H]sphinganine 1-phosphate to human fibroblast monolayers, the label was efficiently removed from the culture medium. In contrast with the reported stability of phosphorylated sphingenine in 3T3 cells [Desai, Zhang, Olivera, Mattie and Spiegel (1992). J. Biol. Chem. 267, 23122-23128] and B16 melanoma cells [Sadahira, Ruan, Hakomuri and Igarashi (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 9686- 9690], sphinganine 1-phosphate appeared to be subjected to a fast and extensive metabolism in fibroblasts, the major pathways being cleavage and dephosphorylation. The first of these pathways, catalysed by sphingosine-phosphate lyase, resulted in the formation of labelled palmitaldehyde, which was recovered, mainly after oxidation, in glycerophospholipids in an ester bond. A smaller part of the palmitaldehyde was reduced and incorporated in alk(en)ylphospholipids. Dephosphorylation of spinganine 1-phosphate, a hitherto overlooked pathway catalysed by an unknown phosphatase(s), gave rise to sphinganine, which was converted by N-acylation into ceramide and then incorporated in spingomyelin and glycosphingolipids. |
last changed |
2002/11/12 16:17 |
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