4BUZ

SIR2 COMPLEX STRUCTURE MIXTURE OF EX-527 INHIBITOR AND REACTION PRODUCTS OR OF REACTION SUBSTRATES P53 PEPTIDE AND NAD

Summary for 4BUZ

• Entry DOI: 10.2210/pdb4buz/pdb
• Related: 4BV2 4BV3 4BVB 4BVE 4BVF 4BVG 4BVH
• Descriptor: NAD-DEPENDENT PROTEIN DEACETYLASE, CELLULAR TUMOR ANTIGEN P53, (1S)-6-chloro-2,3,4,9-tetrahydro-1H-carbazole-1- carboxamide, ... (8 entities in total)
• Functional Keywords: hydrolase, nad-dependent deacetylase, sirtuin, inhibitor complex, ex-527, running reaction
• Biological source: THERMOTOGA MARITIMA; More
• Cellular location: Cytoplasm (By similarity): Q9WYW0; Cytoplasm. Isoform 1: Nucleus. Isoform 2: Nucleus. Isoform 3: Nucleus. Isoform 4: Nucleus. Isoform 7: Nucleus. Isoform 8: Nucleus. Isoform 9: Cytoplasm: P04637
• Total number of polymer chains: 2
• Total formula weight: 30344.21

Authors

Weyand, M.,Lakshminarasimhan, M.,Gertz, M.,Steegborn, C. (deposition date: 2013-06-24, release date: 2013-07-17, Last modification date: 2024-10-23)

Primary citation

Gertz, M.,Fischer, F.,Nguyen, G.T.T.,Lakshminarasimhan, M.,Schutkowski, M.,Weyand, M.,Steegborn, C.
Ex-527 Inhibits Sirtuins by Exploiting Their Unique Nad+-Dependent Deacetylation Mechanism
Proc.Natl.Acad.Sci.USA, 110:E2772-, 2013

PubMed Abstract: Sirtuins are protein deacetylases regulating metabolism and stress responses. The seven human Sirtuins (Sirt1-7) are attractive drug targets, but Sirtuin inhibition mechanisms are mostly unidentified. We report the molecular mechanism of Sirtuin inhibition by 6-chloro-2,3,4,9-tetrahydro-1H-carbazole-1-carboxamide (Ex-527). Inhibitor binding to potently inhibited Sirt1 and Thermotoga maritima Sir2 and to moderately inhibited Sirt3 requires NAD(+), alone or together with acetylpeptide. Crystal structures of several Sirtuin inhibitor complexes show that Ex-527 occupies the nicotinamide site and a neighboring pocket and contacts the ribose of NAD(+) or of the coproduct 2'-O-acetyl-ADP ribose. Complex structures with native alkylimidate and thio-analog support its catalytic relevance and show, together with biochemical assays, that only the coproduct complex is relevant for inhibition by Ex-527, which stabilizes the closed enzyme conformation preventing product release. Ex-527 inhibition thus exploits Sirtuin catalysis, and kinetic isoform differences explain its selectivity. Our results provide insights in Sirtuin catalysis and inhibition with important implications for drug development.

PubMed: 23840057
DOI: 10.1073/PNAS.1303628110

Experimental method

X-RAY DIFFRACTION (1.9 Å)