1C4W:
reference: The 1.9 A resolution crystal structure of phosphono-CheY, an analogue of the active form of the response regulator, CheY., Halkides CJ, McEvoy MM, Casper E, Matsumura P, Volz K, Dahlquist FW, Biochemistry 2000 May 9;39(18):5280-6. PMID: 10819997

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