Nitric oxide oxidises a ferrous mammalian lipoxygenase to a pre-activated ferric species.
Nitric oxide is known as an inhibitor of soybean lipoxygenase-1. Investigating the interaction of a mammalian 15-lipoxygenase with nitric oxide, we found that this enzyme is also inhibited reversibly when incubated with nitric oxide for a short time period (5 s) under anaerobic conditions. This inhibition may be due to the formation of a dissociable lipoxygenase-nitric oxide complex. With longer incubation periods the ferrous lipoxygenase is oxidised to a ferric form. This oxidation renders the enzyme more susceptible to peroxide activation, causing a time-dependent shortening of the kinetic lag phase.
Wiesner
R
R
Institute of Biochemistry, University Clinics Charité, Humboldt University, Berlin, Germany.
Rathmann
J
J
Holzhütter
H G
HG
Stösser
R
R
Mäder
K
K
Nolting
H
H
Kühn
H
H
D000818:Animals; D001093:Arachidonate 15-Lipoxygenase / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D004789:Enzyme Activation; D005290:Ferric Compounds / Q000378:metabolism*; D007700:Kinetics; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000378:metabolism; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism / Q000494:pharmacology*; D010084:Oxidation-Reduction; D011817:Rabbits; D012156:Reticulocytes / Q000201:enzymology*; D013057:Spectrum Analysis
D005290:Ferric Compounds; D008041:Linoleic Acids; D016859:Lipoxygenase Inhibitors; D009569:Nitric Oxide; D019787:Linoleic Acid; D001093:Arachidonate 15-Lipoxygenase