Fig. 1: TsaM is a model system for studying the architectural features that dictate reactivity in the Rieske oxygenase enzyme class.
a Here, it was investigated how the Rieske non-heme iron monooxygenase p-toluenesulfonate methyl-monooxygenase (TsaM) could be tuned to catalyze sequential monooxygenation or dioxygenation reactions. b TsaM, with the help of a reductase, is reported43,44,45 to natively catalyze a monooxygenation reaction that transforms p-toluenesulfonate and 4-methylbenzoate into hydroxymethyl containing products. c This TsaM-catalyzed reaction is reminiscent of the reaction catalyzed by the Rieske oxygenase toluene dioxygenase (TDO) which instead catalyzes a dioxygenation reaction on an aromatic ring adjacent to a methyl group. d The TsaM-catalyzed reaction is also reminiscent of the reaction catalyzed by the Rieske oxygenase chlorophyll(ide) a oxygenase (CAO), which catalyzes sequential monooxygenation reactions on the C7-methyl group of a chlorophyll scaffold47. All Rieske oxygenase catalyzed reactions shown in this figure require a partner reductase protein to mediate the transfer of two electrons to the Rieske [2Fe-2S] cluster.
