Linked Life Data

9562624

Source:http://linkedlifedata.com/resource/pubmed/id/9562624

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1998-7-2
pubmed:abstractText
Dihydroceramide desaturase, which catalyzes the introduction of a double bond at the 4,5-position of the sphingosine base in a dihydroceramide, was assayed in vitro using radiolabeled D-erythro-C18-dihydroceramide (N-stearoyl sphinganine) and homogenates of fetal rat skin, and some enzymatic properties, including substrate specificity, were determined. The ceramide structure, as the enzymatic product, was confirmed by (i) oxidation of the product with 2,3-dicyano-5,6-dichlorobenzoquinone, which revealed the conversion to 3-ketoceramide (3,3'-didehydroceramide), indicating that a double bond was introduced at the adjacent to the C-3 hydroxyl residue of sphinganine, and (ii) mass spectrometry of a long chain base released from the enzymatic product, which revealed a spectrum identical to that of authentic sphingenine. A short chain dihydroceramide, which was radiolabeled at sphinganine through a newly established method, having a C2- or C6-fatty acid was not desaturated by the skin enzyme, whereas that having a C10-, C14-, or C18-acid was desaturated, maximal reactivity being observed for the C14-dihydroceramide. Other enzymatic properties were confirmed: NAD(H) or NADP(H) and a detergent were required for elevation of the activity; the optimum pH was approximately 6.7; and metal cations were not essential, but Zn2+, Cu2+, and Fe2+ were rather inhibitory. These properties of rat skin desaturase were partly similar to those of rat liver microsomes, as reported recently, however, their substrate specificities were different.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-924X
pubmed:author
pubmed:issnType
Print
pubmed:volume
123
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
906-11
pubmed:dateRevised
2007-12-19
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Substrate specificity and some other enzymatic properties of dihydroceramide desaturase (ceramide synthase) in fetal rat skin.
pubmed:affiliation
Departments of Chemistry and Biochemistry, Sapporo Medical University School of Medicine, S1 W17 Chuo-ku, Sapporo 060-8556, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't