8SUX

Structure of E. coli PtuA hexamer

Summary for 8SUX

• Entry DOI: 10.2210/pdb8sux/pdb
• EMDB information: 40762 40763 40778 40779
• Descriptor: PtuA, ADENOSINE-5'-TRIPHOSPHATE (2 entities in total)
• Functional Keywords: ptua, anti-phage, septu system, immune system
• Biological source: Escherichia coli
• Total number of polymer chains: 6
• Total formula weight: 321166.66

Authors

Shen, Z.F.,Yang, X.Y.,Fu, T.M. (deposition date: 2023-05-13, release date: 2024-01-10, Last modification date: 2024-03-27)

Primary citation

Li, Y.,Shen, Z.,Zhang, M.,Yang, X.Y.,Cleary, S.P.,Xie, J.,Marathe, I.A.,Kostelic, M.,Greenwald, J.,Rish, A.D.,Wysocki, V.H.,Chen, C.,Chen, Q.,Fu, T.M.,Yu, Y.
PtuA and PtuB assemble into an inflammasome-like oligomer for anti-phage defense.
Nat.Struct.Mol.Biol., 31:413-423, 2024

PubMed Abstract: Escherichia coli Septu system, an anti-phage defense system, comprises two components: PtuA and PtuB. PtuA contains an ATPase domain, while PtuB is predicted to function as a nuclease. Here we show that PtuA and PtuB form a stable complex with a 6:2 stoichiometry. Cryo-electron microscopy structure of PtuAB reveals a distinctive horseshoe-like configuration. PtuA adopts a hexameric arrangement, organized as an asymmetric trimer of dimers, contrasting the ring-like structure by other ATPases. Notably, the three pairs of PtuA dimers assume distinct conformations and fulfill unique roles in recruiting PtuB. Our functional assays have further illuminated the importance of the oligomeric assembly of PtuAB in anti-phage defense. Moreover, we have uncovered that ATP molecules can directly bind to PtuA and inhibit the activities of PtuAB. Together, the assembly and function of the Septu system shed light on understanding other ATPase-containing systems in bacterial immunity.

PubMed: 38177683
DOI: 10.1038/s41594-023-01172-8

Experimental method

ELECTRON MICROSCOPY (2.93 Å)