8XEW

Cryo-EM structure of defence-associatedsirtuin 2 (DSR2) H171A protein

Summary for 8XEW

• Entry DOI: 10.2210/pdb8xew/pdb
• EMDB information: 38297
• Descriptor: DSR2 H171A (1 entity in total)
• Functional Keywords: cryo-em, defence-associated sirtuin 2 (dsr2) protein, sir2, cell invasion
• Biological source: Bacillus sp. DSM 5850
• Total number of polymer chains: 4
• Total formula weight: 474274.91

Authors

Li, Y.,Zhang, H.,Zheng, Q.,Wu, Y.,Li, S. (deposition date: 2023-12-13, release date: 2024-10-23)

Primary citation

Zhang, H.,Li, Y.,Li, L.,Chen, L.,Zhu, C.,Sun, L.,Dong, P.,Jing, D.,Yang, J.,Fu, L.,Xiao, F.,Xia, N.,Li, S.,Zheng, Q.,Wu, Y.
Structural insights into activation mechanisms on NADase of the bacterial DSR2 anti-phage defense system.
Sci Adv, 10:eadn5691-eadn5691, 2024

PubMed Abstract: As a sirtuin (SIR2) family protein, defense-associated sirtuin2 (DSR2) has been demonstrated to participate in bacterial anti-phage resistance via depleting nicotinamide adenine dinucleotide (NAD) of infected cells, which can be activated by tail tube protein (TTP) and inhibited by DSR anti-defense 1 (DSAD1) of diverse phages. However, the regulating mechanism remains elusive. Here, we determined the cryo-electron microscopy structure of apo DSR2, as well as the respective complex structures with TTP and DSAD1. Structural analyses and biochemical studies reveal that DSR2 forms a tetramer with a SIR2 central core and two distinct conformations. Monomeric TTP preferentially binds to the closed conformation of DSR2, inducing conformational distortions on SIR2 tetramer assembly to activate its NADase activity. DSAD1 combines with the open conformation of DSR2, directly or allosterically inhibiting TTP activation on DSR2 NAD hydrolysis. Our findings decipher the detailed molecule mechanisms for DSR2 NADase activity regulation and lay a foundation for in-depth understanding of the DSR2 anti-phage defense system.

PubMed: 39083599
DOI: 10.1126/sciadv.adn5691

Experimental method

ELECTRON MICROSCOPY (2.92 Å)