| On the specificity of allene oxide cyclase. | |
| | |
MedLine Citation:
|
PMID: 10580327 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Jasmonic acid is a carbocyclic fatty acid that is biosynthesized from alpha-linolenic acid in several steps. The formation of the ring structure of jasmonic acid is catalyzed by the enzyme allene oxide cyclase (EC 5.3.99.6) and involves the cyclization of an unstable allene oxide into the cyclopentenone 12-oxo-10,15(Z)-phytodienoic acid. In this study, a number of allene oxides were generated, and their enzymatic and nonenzymatic cyclization into cyclopentenones was investigated. Nonenzymatic cyclization was observed with allene oxides having one pair of conjugated double bonds and an additional isolated double bond in the beta,gamma position relative to the epoxide group, i.e., the partial structure 4,5-epoxy-1,3,7-octatriene. Enzymatic cyclization took place provided that this structural element was inserted in the fatty acid chain with its epoxide group in the n-6,7 position and the isolated double bond in the n-3 position. A number of oxygenated fatty acids having structural features in common with the natural allene oxides were tested as inhibitors of allene oxide cyclase. Fatty acids having an allene oxide structure in the n-6,7 position but lacking the double bond in the n-3 position, as well as fatty acids having a saturated epoxide group in the n-6,7 position, served as competitive inhibitors of the enzyme. Data on the substrate specificity of allene oxide synthase (EC 4.2.1.92) from corn seeds indicated that fatty acid hydroperoxides with a double bond at n-3 and with the hydroperoxide function at n-6 exhibit the highest affinity but the slowest reaction velocity. |
| | |
Authors:
|
J Ziegler; C Wasternack; M Hamberg |
Related Documents
:
|
17484037 - Hypothesis: the peroxydicarbonic acid cycle in photosynthetic oxygen evolution. 17956237 - Peroxisomal disorders affecting phytanic acid alpha-oxidation: a review. 12633097 - Production of octadienal in the marine diatom skeletonema costatum. 2065777 - 7-tetrahydrobiopterin is an uncoupled cofactor for rat hepatic phenylalanine hydroxylase. 7519327 - Screening for agents inhibiting the mutagenicity of extracts and constituents of tobacc... 21702637 - Experimental observation of strongly bound dimers of sulfuric acid: application to nucl... |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: Lipids Volume: 34 ISSN: 0024-4201 ISO Abbreviation: Lipids Publication Date: 1999 Oct |
Date Detail:
|
Created Date: 1999-12-27 Completed Date: 1999-12-27 Revised Date: 2006-11-15 |
Medline Journal Info:
|
Nlm Unique ID: 0060450 Medline TA: Lipids Country: UNITED STATES |
Other Details:
|
Languages: eng Pagination: 1005-15 Citation Subset: IM |
Affiliation:
|
Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden. ziegler@ice.mpg.de |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Animals Enzyme Stability Humans Intramolecular Oxidoreductases* / analysis, chemistry, metabolism Substrate Specificity |
| Chemical | |
Reg. No./Substance:
|
EC 5.3.-/Intramolecular Oxidoreductases; EC 5.3.99.6/hydroperoxide isomerase |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Hepatocellular carcinoma: treatment with transcatheter arterial chemoembolization.
Next Document: Effects of conjugated linoleic acid on oxygen diffusion-concentration product and depletion in membr...