Enzymes
| UniProtKB help_outline | 8 proteins |
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- Name help_outline N-dodecanoyl-(4R)-hydroxysphinganine Identifier CHEBI:78001 Charge 0 Formula C30H61NO4 InChIKeyhelp_outline NGPJDSJKORHGMX-LXQNXJGFSA-N SMILEShelp_outline CCCCCCCCCCCCCC[C@@H](O)[C@@H](O)[C@H](CO)NC(=O)CCCCCCCCCCC 2D coordinates Mol file for the small molecule Search links Involved in 1 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline H2O Identifier CHEBI:15377 (CAS: 7732-18-5) help_outline Charge 0 Formula H2O InChIKeyhelp_outline XLYOFNOQVPJJNP-UHFFFAOYSA-N SMILEShelp_outline [H]O[H] 2D coordinates Mol file for the small molecule Search links Involved in 6,264 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline (4R)-hydroxysphinganine Identifier CHEBI:64124 Charge 1 Formula C18H40NO3 InChIKeyhelp_outline AERBNCYCJBRYDG-KSZLIROESA-O SMILEShelp_outline CCCCCCCCCCCCCC[C@@H](O)[C@@H](O)[C@@H]([NH3+])CO 2D coordinates Mol file for the small molecule Search links Involved in 22 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline dodecanoate Identifier CHEBI:18262 Charge -1 Formula C12H23O2 InChIKeyhelp_outline POULHZVOKOAJMA-UHFFFAOYSA-M SMILEShelp_outline C(CCCCCCCC)CCC([O-])=O 2D coordinates Mol file for the small molecule Search links Involved in 33 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Cross-references
| RHEA:41303 | RHEA:41304 | RHEA:41305 | RHEA:41306 | |
|---|---|---|---|---|
| Reaction direction help_outline | undefined | left-to-right | right-to-left | bidirectional |
| UniProtKB help_outline |
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Related reactions help_outline
More general form(s) of this reaction
Publications
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The reverse activity of human acid ceramidase.
Okino N., He X., Gatt S., Sandhoff K., Ito M., Schuchman E.H.
An overexpression system was recently developed to produce and purify recombinant, human acid ceramidase. In addition to ceramide hydrolysis, the purified enzyme was able to catalyze ceramide synthesis using [14C]lauric acid and sphingosine as substrates. Herein we report detailed characterization ... >> More
An overexpression system was recently developed to produce and purify recombinant, human acid ceramidase. In addition to ceramide hydrolysis, the purified enzyme was able to catalyze ceramide synthesis using [14C]lauric acid and sphingosine as substrates. Herein we report detailed characterization of this acid ceramidase-associated "reverse activity" and provide evidence that this reaction occurs in situ as well as in vitro. The pH optimum of the reverse reaction was approximately 5.5, as compared with approximately 4.5 for the hydrolysis reaction. Non-ionic detergents and zinc cations inhibited the activity, whereas most other cations were stimulatory. Of note, sphingomyelin also was very inhibitory toward this reaction, whereas the anionic lipids, phosphatidic acid and phosphatidylserine, were stimulatory. Of various sphingosine stereoisomers tested in the reverse reaction, only the natural, D-erythro form could efficiently serve as a substrate. Using D-erythro-sphingosine and lauric acid as substrates, the reaction followed normal Michaelis-Menten kinetics. The Km and Vmax values toward sphingosine were 23.75 microM and 208.3 pmol/microg/h, respectively, whereas for lauric acid they were 73.76 microM and 232.5 pmol/microg/h, respectively. Importantly, the reverse activity was reduced in cell lysates from a Farber disease patient to the same extent as the acid ceramidase activity. Furthermore, when 12-(N-methyl-N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)) (NBD)-conjugated lauric acid and sphingosine were added to cultured lymphoblasts from a Farber disease patient in the presence of fumonisin B (1), the conversion to NBD-ceramide was reduced approximately 30% when compared with normal cells. These data provide important new information on human acid ceramidase and further document its central role in sphingolipid metabolism. << Less
J. Biol. Chem. 278:29948-29953(2003) [PubMed] [EuropePMC]
This publication is cited by 5 other entries.