Linked Life Data

2713352

Source:http://linkedlifedata.com/resource/pubmed/id/2713352

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1989-6-22
pubmed:abstractText
Rat liver dolichyl-phosphomannose synthase is optimally active when the enzyme is reconstituted with lipids that prefer a nonlamellar macroscopic organization in isolation, such as phosphatidylethanolamine (PE), but the enzyme is only negligibly active in the presence of lipids that normally form stable bilayers, such as phosphatidylcholine (PC) [Jensen, J.W., & Schutzbach, J.S. (1985) Eur. J. Biochem. 153, 41-48]. We now report that the activity of the synthase can be modulated by incorporating diacylglycerol and lysophosphatidylcholine into the lipid matrix. Enzyme activity in PC bilayers was stimulated by the presence of diacylglycerol, a lipid that has a conical dynamic molecular shape and disrupts bilayer stability. In PC/diacylglycerol mixtures the apparent Km for dolichyl-P was 30-fold lower than the apparent Km for the polyprenol acceptor in PC membranes. Enzyme activity was also stimulated when diacylglycerol was generated in situ by incubation of PC vesicles with phospholipase C. In contrast, the activity of enzyme reconstituted in PE dispersions, or in PE/PC bilayers, was markedly inhibited by the presence of lysophospholipids. Enzyme activity was also reduced by the in situ generation of lysophospholipids in PE/PC vesicles by incubation with phospholipase A2. Since lysophospholipids and diacylglycerols arise in vivo as products of phospholipid metabolism, modulation of enzyme activity by these compounds may represent a potential regulatory mechanism for the synthesis of oligosaccharide lipids.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
24
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
851-5
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Phospholipase-induced modulation of dolichyl-phosphomannose synthase activity.
pubmed:affiliation
Department of Microbiology, University of Alabama, Birmingham 35294.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.