label: 3-hydroxyindolin-2-one monooxygenase activity
label_lc: 3-hydroxyindolin-2-one monooxygenase activity
description: "Catalysis of the reaction: 3-hydroxyindolin-2-one + O2 + reduced [NADPH--hemoprotein reductase] = 2-hydroxy-2H-1,4-benzoxazin-3(4H)-one + H+ + H2O + oxidized [NADPH--hemoprotein reductase]."