osmotic activation of nasal tissue with mannitol activates 15-LO-1 leading to increased amounts of 15(S)-hydroxyeicosatetranoic acid in nasal lavage, and the levels of 15(S)-hydroxyeicosatetranoic acid are associated with nasal symptoms
positional specificity of wild-type 15-LOX-2 does hardly depend on the pH of the reaction buffer. The pH sensitivity can be induced by introduction of a His at the active site
under cellular conditions (low fatty acid and low oxygen concentrations), the allosteric binding of 12(S)-hydroxyeicosatetraenoic acid to 15-hLO-1 can increase the substrate specificity of 15-hLO-1 toward arachidonic acid over linoleic acid significantly, tunneling mechanism
ALOX15 is usually present as catalytically silent ferrous enzyme. To initiate fatty acid oxygenation, the enzyme must first be oxidized to a ferric form capable of initiating hydrogen abstraction. Unfortunately, single activation of the enzyme is not sufficient to keep it running, since during catalysis small quantities of radical intermediates might escape from the active site leaving the enzyme in an inactive ferrous (Fe2+) form. To keep the reaction at quasistationary levels, repeated enzyme activation is required and the primary oxygenation products appear to serve as enzyme activators. In this sense, the LOX exhibits autocatalytic properties
ALOX15 is usually present as catalytically silent ferrous enzyme. To initiate fatty acid oxygenation, the enzyme must first be oxidized to a ferric form capable of initiating hydrogen abstraction. Unfortunately, single activation of the enzyme is not sufficient to keep it running, since during catalysis small quantities of radical intermediates might escape from the active site leaving the enzyme in an inactive ferrous (Fe2+) form. To keep the reaction at quasistationary levels, repeated enzyme activation is required and the primary oxygenation products appear to serve as enzyme activators. In this sense, the LOX exhibits autocatalytic properties
the potent vasoconstricting and pro-inflammatory hormone angiotensin II (Ang II) led to increases in leukocyte-type 12-LO mRNA and protein levels, as well as increased enzyme activity
ALOX15 is usually present as catalytically silent ferrous enzyme. To initiate fatty acid oxygenation, the enzyme must first be oxidized to a ferric form capable of initiating hydrogen abstraction. Unfortunately, single activation of the enzyme is not sufficient to keep it running, since during catalysis small quantities of radical intermediates might escape from the active site leaving the enzyme in an inactive ferrous (Fe2+) form. To keep the reaction at quasistationary levels, repeated enzyme activation is required and the primary oxygenation products appear to serve as enzyme activators. In this sense, the LOX exhibits autocatalytic properties
ALOX15 is usually present as catalytically silent ferrous enzyme. To initiate fatty acid oxygenation, the enzyme must first be oxidized to a ferric form capable of initiating hydrogen abstraction. Unfortunately, single activation of the enzyme is not sufficient to keep it running, since during catalysis small quantities of radical intermediates might escape from the active site leaving the enzyme in an inactive ferrous (Fe2+) form. To keep the reaction at quasistationary levels, repeated enzyme activation is required and the primary oxygenation products appear to serve as enzyme activators. In this sense, the LOX exhibits autocatalytic properties
ALOX15 is usually present as catalytically silent ferrous enzyme. To initiate fatty acid oxygenation, the enzyme must first be oxidized to a ferric form capable of initiating hydrogen abstraction. Unfortunately, single activation of the enzyme is not sufficient to keep it running, since during catalysis small quantities of radical intermediates might escape from the active site leaving the enzyme in an inactive ferrous (Fe2+) form. To keep the reaction at quasistationary levels, repeated enzyme activation is required and the primary oxygenation products appear to serve as enzyme activators. In this sense, the LOX exhibits autocatalytic properties. Studying the oxygenation of 15S-HETE by pure rabbit ALOX15, it is found that the corresponding oxygenation product(s) does not activate the enzyme, while molecular dioxygen serves not only as a lipoxygenase substrate, but also impacts peroxide-dependent enzyme activation
ALOX15 is usually present as catalytically silent ferrous enzyme. To initiate fatty acid oxygenation, the enzyme must first be oxidized to a ferric form capable of initiating hydrogen abstraction. Unfortunately, single activation of the enzyme is not sufficient to keep it running, since during catalysis small quantities of radical intermediates might escape from the active site leaving the enzyme in an inactive ferrous (Fe2+) form. To keep the reaction at quasistationary levels, repeated enzyme activation is required and the primary oxygenation products appear to serve as enzyme activators. In this sense, the LOX exhibits autocatalytic properties. Studying the oxygenation of 15S-HETE by pure rabbit ALOX15, it is found that the corresponding oxygenation product(s) does not activate the enzyme, while molecular dioxygen serves not only as a lipoxygenase substrate, but also impacts peroxide-dependent enzyme activation
ALOX15 is usually present as catalytically silent ferrous enzyme. To initiate fatty acid oxygenation, the enzyme must first be oxidized to a ferric form capable of initiating hydrogen abstraction. Unfortunately, single activation of the enzyme is not sufficient to keep it running, since during catalysis small quantities of radical intermediates might escape from the active site leaving the enzyme in an inactive ferrous (Fe2+) form. To keep the reaction at quasistationary levels, repeated enzyme activation is required and the primary oxygenation products appear to serve as enzyme activators. In this sense, the LOX exhibits autocatalytic properties