2-oxoglutarate-dependent dioxygenase; part of the gene cluster that mediates the biosynthesis of the psychoactive metabolites ibotenic acid and muscimol (PubMed:32233056). The first committed step is glutamate hydroxylation by the 2-oxoglutarate-dependent dioxygenase iboH, and the last step is decarboxylation of ibotenic acid to muscimol by the decarboxylase iboD (PubMed:32233056). The order of the intermediate reactions is somewhat ambiguous (Probable). IboA likely activates the carboxylic acid at position 5 to introduce an amide bond, and the flavin monooxygenase iboF generates the N-O bond (Probable). There are several options for the latter step (Probable). One option is that iboF directly hydroxylates the amide nitrogen formed by iboA to produce a hydroxamic acid species (Probable). Another option is that iboF hydroxylates an external N-containing compound, whose resulting N-O bond is subsequently introduced into the hydroxyglutamate scaffold (Probable). The paralogous PLP-dependent cystathionine gamma-synthase-like enzymes iboG1 and iboG2 are likely involved in substitution of the OH group at position 3 by the O-N moiety (Probable). The first cyclic intermediate is most probably tricholomic acid which is likely desaturated to ibotenic acid by the cytochrome P450 monooxygenase iboC (Probable). 2-oxoglutarate + L-glutamate + O2 = (3R)-3-hydroxy-L-glutamate + CO2 + succinate Binds 1 Fe(2+) ion per subunit. Secondary metabolite biosynthesis. Expression is highly induced during artificial growth in symbiosis with Populus, which is close to its natural condition. Belongs to the iron/ascorbate-dependent oxidoreductase family.