Linked Life Data

7096336

Source:http://linkedlifedata.com/resource/pubmed/id/7096336

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
15
pubmed:dateCreated
1982-9-17
pubmed:abstractText
Alkyldihydroxyacetone-P (alkyl-DHAP) synthase, the enzyme that forms the ether linkage of alkyl and alk-1-enyl glycerolipids, has been solubilized from ehrlich ascites cell microsomes using Triton X-100 and acetone precipitation. the solubilized enzyme, which is stabilized by glycerol or ethylene glycol, was then purified further by chromatography on DEAE-cellulose, QAE-Sephadex, Matrex Red, and hydroxylapatite with the aid of a new rapid assay method using DEAE-cellulose disks. Four enzymes involved in the metabolism of acyl-DHAP and alkyl-DHAP (acyl-DHAP/alkyl-DHAP oxidoreductase, DHAP acyltransferase, alkyl-DHAP phosphohydrolase, and a dinitrofluorobenzene-insensitive acyl-DHAP acylhydrolase) are removed under these conditions along with endogenous fatty acids and fatty alcohols. Two other activities copurify with the alkyl-DHAP synthase forward reaction: an acyl exchange reaction, in which [1-14C]palmitic acid is incorporated into palmitoyl-DHAP, and an alkyl exchange reaction, in which [1-14C]hexadecanol is incorporated into hexadecyl-DHAP. Exchange reactions of this type are characteristic properties of a ping-pong mechanism but not a sequential mechanism. This is confirmed by documentation that palmitic acid is a competitive inhibitor with respect to hexadecanol. In addition, low levels of palmitoyl-DHAP (less than 100 microM) show competitive inhibition with respect to hexadecanol, possibly due to palmitic acid formed from palmitoyl-DHAP by alkyl-DHAP synthase under these conditions. Based on the observations presented here and previously, a molecular mechanism for alkyl-DHAP synthase is proposed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
257
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8835-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1982
pubmed:articleTitle
Alkyldihydroxyacetone-P synthase. Solubilization, partial purification, new assay method, and evidence for a ping-pong mechanism.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't