Crystal structure of a lipoxygenase in complex with substrate: the arachidonic acid-binding site of 8R-lipoxygenase.
J Biol Chem
; 289(46): 31905-31913, 2014 Nov 14.
Article
em En
| MEDLINE
| ID: mdl-25231982
ABSTRACT
Lipoxygenases (LOX) play critical roles in mammalian biology in the generation of potent lipid mediators of the inflammatory response; consequently, they are targets for the development of isoform-specific inhibitors. The regio- and stereo-specificity of the oxygenation of polyunsaturated fatty acids by the enzymes is understood in terms of the chemistry, but structural observation of the enzyme-substrate interactions is lacking. Although several LOX crystal structures are available, heretofore the rapid oxygenation of bound substrate has precluded capture of the enzyme-substrate complex, leaving a gap between chemical and structural insights. In this report, we describe the 2.0 Å resolution structure of 8R-LOX in complex with arachidonic acid obtained under anaerobic conditions. Subtle rearrangements, primarily in the side chains of three amino acids, allow binding of arachidonic acid in a catalytically competent conformation. Accompanying experimental work supports a model in which both substrate tethering and cavity depth contribute to positioning the appropriate carbon at the catalytic machinery.
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Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Araquidonato Lipoxigenases
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article