Double-oxygenating
lipoxygenase (LOX) converted C20- and C22-polyunsaturated
fatty acids (PUFAs) into C20 dihydroxy
fatty acids (DiHFAs) as inflammatory mediators and C22 DiHFAs as specialized pro-resolving mediators, which are involved in the resolution of
inflammation and
infection in humans, and their isomers, respectively. However, the quantitative bioconversion of C20- and C22-PUFAs into 9S,15S- and 11S,17S-DiHFAs has been not attempted to date, respectively. Here, we performed the efficient quantitative production of 9S,15S- and 11S,17S-DiHFAs by Escherichia coli expressing 9S-LOX from Sphingopyxis macrogoltabida. The optimal bioconversion conditions of the C20 PUFA
arachidonic acid or the C22-PUFA
docosahexaenoic acid were pH 8.5, 35 °C, 6 mM substrate, and 5 g dry cells/L for C20 PUFAs or 7 g dry cells/L for C22-PUFAs, respectively. Under these conditions, E. coli expressing double-oxygenating 9S-LOX from S. macrogoltabida converted
arachidonic acid,
eicosapentaenoic acid, docosapentaenoic acidn-3, and
docosahexaenoic acid into 5.85 mM 9S,15S-dihydroxyeicosatetraenoic
acid, 5.79 mM 9S,15S-dihydroxyeicosapentaenoic
acid, 5.89 mM 11S,17S-hydroxydocosapentaenoic acidn-3, and 5.24 mM 11S,17S-dihydroxydocosahexaenoic
acid in 40, 30, 50, and 60 min, with conversion yields of 97.5%, 96.5%, 98.1%, and 87.3%; and volumetric productivities of 8.78, 11.6, 7.07, and 5.24 mM/h, respectively. To date, these are the highest concentrations, conversion yields, and volumetric productivities reported in the bioconversion of C20- and C22-PUFAs into DiHFAs.