2GW8:
reference: Structure of the PII signal transduction protein of Neisseria meningitidis at 1.85 A resolution., Nichols CE, Sainsbury S, Berrow NS, Alderton D, Saunders NJ, Stammers DK, Owens RJ, Acta Crystallograph Sect F Struct Biol Cryst Commun. 2006 Jun 1;62(Pt, 6):494-7. Epub 2006 May 31. PMID: 16754965

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