Structure of the sirtuin-linked macrodomain SAV0325 from Staphylococcus aureus.
Cells use the post-translational modification ADP-ribosylation to control a host of biological activities. In some pathogenic bacteria, an operon-encoded mono-ADP-ribosylation cycle mediates response to host-induced oxidative stress. In this system, reversible mono ADP-ribosylation of a lipoylated target protein represses oxidative stress response. An NAD(+) -dependent sirtuin catalyzes the single ADP-ribose (ADPr) addition, while a linked macrodomain-containing protein removes the ADPr. Here we report the crystal structure of the sitruin-linked macrodomain protein from Staphylococcus aureus, SauMacro (also known as SAV0325) to 1.75-Å resolution. The monomeric SauMacro bears a previously unidentified Zn(2+) -binding site that putatively aids in substrate recognition and catalysis. An amino-terminal three-helix bundle motif unique to this class of macrodomain proteins provides a structural scaffold for the Zn(2+) site. Structural features of the enzyme further indicate a cleft proximal to the Zn(2+) binding site appears well suited for ADPr binding, while a deep hydrophobic channel in the protein core is suitable for binding the lipoate of the lipoylated protein target.
['Appel|C Denise|CD|', 'Feld|Geoffrey K|GK|', 'Wallace|Bret D|BD|', 'Williams|R Scott|RS|']
D001426:Bacterial Proteins D018360:Crystallography, X-Ray D000072417:Protein Domains D037761:Sirtuins D013211:Staphylococcus aureus D015032:Zinc
macrodomain SAV0325 Staphylococcus aureus ADP-ribosylation oxidative stress ADP-ribose SauMacro lipoate X-ray crystallography adenosine diphosphate ribose lipolyation