Electron Spin-Echo Envelope Modulation Studies on Copper Site of Particulate Methane Monooxygenase from Methylosinus trichosporium OB3b

The electron spin-echo envelope modulation (ESEEM) effect was studied on the type II copper site in the particulate methane monooxygenase (pMMO) from Methylosinus trichosporium OB3b. From comparing the ESEEM spectra of the membranes treated with ethylenediaminetetraacetic acid and some model compounds, it was clarified that there were at least two imidazole ligands bound copper (II) in pMMO.