3C90:
reference: The 1.25 A resolution structure of phosphoribosyl-ATP pyrophosphohydrolase from Mycobacterium tuberculosis., Javid-Majd F, Yang D, Ioerger TR, Sacchettini JC, Acta Crystallogr D Biol Crystallogr. 2008 Jun;64(Pt 6):627-35. Epub 2008, May 14. PMID: 18560150

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