1UFL:
reference: Crystal structures of the signal transducing protein GlnK from Thermus thermophilus HB8., Sakai H, Wang H, Takemoto-Hori C, Kaminishi T, Yamaguchi H, Kamewari Y, Terada T, Kuramitsu S, Shirouzu M, Yokoyama S, J Struct Biol 2005 Jan;149(1):99-110. PMID: 15629661

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