1S7G image
Deposition Date 2004-01-29
Release Date 2004-03-23
Last Version Date 2023-08-23
Entry Detail
PDB ID:
1S7G
Keywords:
Title:
Structural Basis for the Mechanism and Regulation of Sir2 Enzymes
Biological Source:
Source Organism:
Host Organism:
Method Details:
Experimental Method:
Resolution:
2.30 Å
R-Value Free:
0.24
R-Value Work:
0.20
R-Value Observed:
0.20
Space Group:
P 21 21 2
Macromolecular Entities
Polymer Type:polypeptide(L)
Molecule:NAD-dependent deacetylase 2
Gene (Uniprot):cobB2
Chain IDs:A, B, C, D, E
Chain Length:253
Number of Molecules:5
Biological Source:Archaeoglobus fulgidus
Primary Citation
Structural basis for the mechanism and regulation of sir2 enzymes
Mol.Cell 13 639 648 (2004)
PMID: 15023335 DOI: 10.1016/S1097-2765(04)00082-6

Abstact

Sir2 proteins form a family of NAD(+)-dependent protein deacetylases required for diverse biological processes, including transcriptional silencing, suppression of rDNA recombination, control of p53 activity, regulation of acetyl-CoA synthetase, and aging. Although structures of Sir2 enzymes in the presence and absence of peptide substrate or NAD(+) have been determined, the role of the enzyme in the mechanism of deacetylation and NAD(+) cleavage is still unclear. Here, we present additional structures of Sir2Af2 in several differently complexed states: in a productive complex with NAD(+), in a nonproductive NAD(+) complex with bound ADP-ribose, and in the unliganded state. We observe a new mode of NAD(+) binding that seems to depend on acetyl-lysine binding, in which the nicotinamide ring of NAD(+) is buried in the highly conserved "C" pocket of the enzyme. We propose a detailed structure-based mechanism for deacetylation and nicotinamide inhibition of Sir2 consistent with mutagenesis and enzymatic studies.

Legend

Protein

Chemical

Disease

Primary Citation of related structures