3W55:
reference: Role of a cysteine residue in the active site of ERK and the MAPKK family., Ohori M, Kinoshita T, Yoshimura S, Warizaya M, Nakajima H, Miyake H, Biochem Biophys Res Commun. 2007 Feb 16;353(3):633-7. Epub 2006 Dec 20. PMID: 17194451

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