4buz

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

spinqualitylabelsall models 4buz, resolution 1.90Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 4buz is a 2 chain structure with sequence from Homo sapiens and Thermotoga maritima. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.9Å Ligands: ALY, EDO, NAD, OAD, OCZ, ZN Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function NPD_THEMA NAD-dependent protein deacetylase which modulates the activities of several enzymes which are inactive in their acetylated form. Has also depropionylation activity in vitro. Also able to ADP-ribosylate peptide substrates with Arg or Lys in the +2 position. The role of this function in vivo is not clear. Publication Abstract from PubMed 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. Ex-527 inhibits Sirtuins by exploiting their unique NAD+-dependent deacetylation mechanism.,Gertz M, Fischer F, Nguyen GT, Lakshminarasimhan M, Schutkowski M, Weyand M, Steegborn C Proc Natl Acad Sci U S A. 2013 Jul 9. PMID:23840057 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA