2H3B:
reference: Structure of Nampt/PBEF/visfatin, a mammalian NAD(+) biosynthetic enzyme., Wang T, Zhang X, Bheda P, Revollo JR, Imai SI, Wolberger C, Nat Struct Mol Biol. 2006 Jul;13(7):661-662. Epub 2006 Jun 18. PMID: 16783373

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