PUBLICATION
Stereocontrol of arachidonic acid oxygenation by vertebrate lipoxygenases, newly cloned zebrafish lipoxygenase1 does not follow the A-vs-G concept
- Authors
- Jansen, C., Hofheinz, K., Vogel, R., Anton, M., Reddanna, P., Kuhn, H., and Walther, M.
- ID
- ZDB-PUB-110907-9
- Date
- 2011
- Source
- The Journal of biological chemistry 286(43): 37804-12 (Journal)
- Registered Authors
- Keywords
- eicosanoid, enzyme catalysis, leukotriene, lipid oxidation, lipoxygenase pathway, zebrafish, enantioselectivity, stereochemistry
- MeSH Terms
-
- Macaca mulatta
- Arachidonic Acid/genetics
- Arachidonic Acid/metabolism*
- Animals
- Humans
- PubMed
- 21880725 Full text @ J. Biol. Chem.
Abstract
Animal lipoxygenases (LOX) are classified according to their specificity of arachidonic acid oxygenation and previous sequence alignments suggested that S-LOX contain a conserved Ala at a critical position at the active site but R-LOX carry a Gly instead. Here we cloned, expressed and characterized a novel LOX-isoform from the model vertebrate Danio rerio (zebrafish) that carries a Gly at this critical position classifying this enzyme as putative arachidonic acid R-LOX. Surprisingly, the almost exclusive arachidonic acid oxygenation product was 12S-H(p)ETE and extensive mutation around G410 failed to induce R-lipoxygenation. This finding prompted us to explore the importance of the corresponding amino acids in other vertebrate S-LOXs. We found that A-to-G exchange in human 15-LOX2 and human platelet 12-LOX induced major alterations in the reaction specificity with an increase of specific R-oxygenation products. For mouse 5-LOX, for 12/15-LOX from rabbits, men, rhesus monkeys, orang-utans and mice only minor alterations in the reaction specificity were observed. For these enzymes S-HETE isomers remained the major oxygenation products whereas chiral R-HETEs contributed only 10-30% to the total product mixture. Taken together this data indicates that the A-vs-G concept may not always predict the reaction specificity of vertebrate LOX-isoforms.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping