1SZD:
reference: Structural basis for nicotinamide cleavage and ADP-ribose transfer by NAD(+)-dependent Sir2 histone/protein deacetylases., Zhao K, Harshaw R, Chai X, Marmorstein R, Proc Natl Acad Sci U S A 2004 Jun 8;101(23):8563-8. Epub 2004 May 18. PMID: 15150415

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