Lipoxygenase 2 from Cyanothece sp. controls dioxygen insertion by steric shielding and substrate fixation.

ABSTRACT: The biological function of lipoxygenases depends on the regio and stereo specific formation of fatty acid-derived hydroperoxides and different concepts exist to explain the mechanism that directs dioxygen to a specific carbon atom within the substrate. Here, we report the 1.8 Å resolution crystal structure of a cyanobacterial lipoxygenase that produces bis-allylic hydroperoxides (CspLOX2). Site directed mutagenesis experiments combined with computational approaches reveal that residues around the active site direct dioxygen to a preferred carbon atom and stereo configuration in the substrate fatty acid. Modulating the cavity volume around the pentadiene system of linoleic acid shifted the product formation towards 9S-, 9R-, 13S- or 13R-hydroperoxides in correlation with the site of mutatio

SUBMITTER: Newie J 

PROVIDER: S-EPMC5437038 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature