Molecule of the Month: Sirtuins
Sirtuin activation is being explored as a way to slow aging.
A Family of Sirtuins
Exploring the Structure
Sirtuin in Action
Two structures show a bacterial sirtuin before and after its reaction. On the left (PDB entry 2h4f), NAD is bound in the active site along with a small peptide from P53 tumor suppressor. An acetylated lysine in the peptide is gripped by the enzyme and positioned close to the NAD. After the reaction (PDB entry 2h59). the acetyl group has been transferred to NAD, releasing the nicotinamide ring (shown in magenta in the first structure) in the process. Click on the image to explore these structures in more detail.
Topics for Further Discussion
- Many structures for human sirtuins have been determined: find them by searching for “sirtuin”, then limit the search to “Homo sapiens” using the options in the left-hand menu.
- Sirtuins are flexible, opening and closing during their reactions. Use the structure comparison tool to explore this flexibility, for instance, in two forms of SIRT2 (1j8f and 3zgv).
September 2017, David Goodselldoi:10.2210/rcsb_pdb/mom_2017_9