Linked Life Data

12684876

Source:http://linkedlifedata.com/resource/pubmed/id/12684876

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2003-5-20
pubmed:abstractText
While de novo fatty acid synthesis uses acetyl-CoA, fatty acid elongation uses longer-chain acyl-CoAs as primers. Several mutations that interfere with fatty acid elongation in yeast have already been described, suggesting that there may be different elongases for medium- and long-chain acyl-CoA primers. In the present study, an experimental approach is described that allows differential characterization of the various yeast elongases in vitro. Based on their characteristic primer specificities and product patterns, at least three different yeast elongases are defined. Elongase I extends C12-C16 fatty acyl-CoAs to C16-C18 fatty acids. Elongase II elongates palmitoyl-CoA and stearoyl-CoA up to C22 fatty acids, and elongase III synthesizes 20-26-carbon fatty acids from C18-CoA primers. Elongases I, II and III are specifically inactivated in, respectively, elo1, elo2 and elo3 mutants. Elongases II and III share the same 3-ketoacyl reductase, which is encoded by the YBR159w gene. Inactivation of YBR159w inhibits in vitro fatty acid elongation after the first condensation reaction. Although in vitro elongase activity is absent, the mutant nevertheless contains 10-30% of normal VLCFA levels. On the basis of this finding, an additional elongating activity is inferred to be present in vivo. ybr159Delta cells show synthetic lethality in the presence of cerulenin, which inactivates fatty acid synthase. An involvement of FAS in VLCFA synthesis may account for these findings, but remains to be demonstrated directly. Alternatively, a vital role for C18 and C20 hydroxyacids, which are dramatically overproduced in ybr159Delta cells, may be postulated.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1617-4615
pubmed:author
pubmed:issnType
Print
pubmed:volume
269
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
290-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Functional differentiation and selective inactivation of multiple Saccharomyces cerevisiae genes involved in very-long-chain fatty acid synthesis.
pubmed:affiliation
Lehrstuhl für Biochemie, Universität Erlangen-Nürnberg, Staudtstrasse 5, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't