Catalyses the last step in the biosynthesis of rebeccamycin, an indolocarbazole alkaloid produced by the bacterium Lechevalieria aerocolonigenes. The enzyme is able to use a wide variety substrates, tolerating variation on the imide heterocycle, deoxygenation of the sugar moiety, and even indolocarbazole glycoside anomers [1]. The enzyme is a member of the general acid/base-dependent O-methyltransferase family [2].
