3NVA:
reference: Structure of the dimeric form of CTP synthase from Sulfolobus solfataricus., Lauritsen I, Willemoes M, Jensen KF, Johansson E, Harris P, Acta Crystallogr Sect F Struct Biol Cryst Commun. 2011 Feb 1;67(Pt, 2):201-8. Epub 2011 Jan 21. PMID: 21301086

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