1KUT:
reference: Structure of SAICAR synthase from Thermotoga maritima at 2.2 angstroms reveals an unusual covalent dimer., Zhang R, Skarina T, Evdokimova E, Edwards A, Savchenko A, Laskowski R, Cuff ME, Joachimiak A, Acta Crystallograph Sect F Struct Biol Cryst Commun. 2006 Apr 1;62(Pt, 4):335-9. Epub 2006 Mar 25. PMID: 16582479

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