Linked Life Data

2823886

Source:http://linkedlifedata.com/resource/pubmed/id/2823886

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
1988-1-20
pubmed:abstractText
When arachidonic acid is added to lysates of rat polymorphonuclear leukocytes, it is oxidized to (5S)-hydroperoxy-6(E),8(Z),11(Z),14(Z)-eicosatetraenoic acid (5-HPETE). The 5-HPETE then partitions between reduction to the 5-hydroxyeicosanoid and conversion to leukotriene A4 (LTA4). Both steps in the formation of LTA4 are catalyzed by the enzyme 5-lipoxygenase. When [3H]arachidonic acid and unlabeled 5-HPETE were incubated together with 5-lipoxygenase, approximately 20% of the arachidonic acid oxidized at low enzyme concentrations was converted to LTA4 without reduction of the specific radioactivity of the LTA4 by the unlabeled 5-HPETE. A significant fraction of the [3H]-5-HPETE intermediate that is formed from arachidonic acid must therefore be converted directly to LTA4 without dissociation of the intermediate from the enzyme. This result predicts that even in the presence of high levels of peroxidase activity, which will trap any free 5-HPETE by reduction, the minimum efficiency of conversion of 5-HPETE to LTA4 will be approximately 20%, and this prediction was confirmed. 5-HPETE was found to be a competitive substrate relative to arachidonic acid, so that it is likely that the two substrates share a common active site.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5684-9
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Kinetics of leukotriene A4 synthesis by 5-lipoxygenase from rat polymorphonuclear leukocytes.
pubmed:affiliation
Merrell Dow Research Institute, Cincinnati, Ohio 45215.
pubmed:publicationType
Journal Article