8RKX

Procapsid of bacteriophage JBD30 computed in I4 symmetry

Summary for 8RKX

• Entry DOI: 10.2210/pdb8rkx/pdb
• EMDB information: 19285
• Descriptor: Bacteriophage Mu GpT domain-containing protein (1 entity in total)
• Functional Keywords: bacteriophage, virion, procapsid, virus
• Biological source: Pseudomonas phage JBD30
• Total number of polymer chains: 7
• Total formula weight: 234448.95

Authors

Valentova, L.,Fuzik, T.,Plevka, P. (deposition date: 2023-12-30, release date: 2024-08-14, Last modification date: 2024-10-16)

Primary citation

Valentova, L.,Fuzik, T.,Novacek, J.,Hlavenkova, Z.,Pospisil, J.,Plevka, P.
Structure and replication of Pseudomonas aeruginosa phage JBD30.
Embo J., 43:4384-4405, 2024

PubMed Abstract: Bacteriophages are the most abundant biological entities on Earth, but our understanding of many aspects of their lifecycles is still incomplete. Here, we have structurally analysed the infection cycle of the siphophage Casadabanvirus JBD30. Using its baseplate, JBD30 attaches to Pseudomonas aeruginosa via the bacterial type IV pilus, whose subsequent retraction brings the phage to the bacterial cell surface. Cryo-electron microscopy structures of the baseplate-pilus complex show that the tripod of baseplate receptor-binding proteins attaches to the outer bacterial membrane. The tripod and baseplate then open to release three copies of the tape-measure protein, an event that is followed by DNA ejection. JBD30 major capsid proteins assemble into procapsids, which expand by 7% in diameter upon filling with phage dsDNA. The DNA-filled heads are finally joined with 180-nm-long tails, which bend easily because flexible loops mediate contacts between the successive discs of major tail proteins. It is likely that the structural features and replication mechanisms described here are conserved among siphophages that utilize the type IV pili for initial cell attachment.

PubMed: 39143239
DOI: 10.1038/s44318-024-00195-1

Experimental method

ELECTRON MICROSCOPY (4.01 Å)