8VDC

SaPI1 portal structure in mature capsids without DNA

Summary for 8VDC

• Entry DOI: 10.2210/pdb8vdc/pdb
• EMDB information: 43033 43142 43143 43145 43146 43147
• Descriptor: Portal protein, Connector (2 entities in total)
• Functional Keywords: portal, phage, sapi, structural protein
• Biological source: Dubowvirus dv80alpha; More
• Total number of polymer chains: 2
• Total formula weight: 72361.40

Authors

Mukherjee, A.,Kizziah, J.L.,Dokland, T. (deposition date: 2023-12-14, release date: 2024-01-10, Last modification date: 2024-01-17)

Primary citation

Mukherjee, A.,Kizziah, J.L.,Hawkins, N.C.,Nasef, M.O.,Parker, L.K.,Dokland, T.
Structure of the Portal Complex from Staphylococcus aureus Pathogenicity Island 1 Transducing Particles In Situ and In Isolation.
J.Mol.Biol., 436:168415-168415, 2023

PubMed Abstract: Staphylococcus aureus is an important human pathogen, and the prevalence of antibiotic resistance is a major public health concern. The evolution of pathogenicity and resistance in S. aureus often involves acquisition of mobile genetic elements (MGEs). Bacteriophages play an especially important role, since transduction represents the main mechanism for horizontal gene transfer. S. aureus pathogenicity islands (SaPIs), including SaPI1, are MGEs that carry genes encoding virulence factors, and are mobilized at high frequency through interactions with specific "helper" bacteriophages, such as 80α, leading to packaging of the SaPI genomes into virions made from structural proteins supplied by the helper. Among these structural proteins is the portal protein, which forms a ring-like portal at a fivefold vertex of the capsid, through which the DNA is packaged during virion assembly and ejected upon infection of the host. We have used high-resolution cryo-electron microscopy to determine structures of the S. aureus bacteriophage 80α portal itself, produced by overexpression, and in situ in the empty and full SaPI1 virions, and show how the portal interacts with the capsid. These structures provide a basis for understanding portal and capsid assembly and the conformational changes that occur upon DNA packaging and ejection.

PubMed: 38135177
DOI: 10.1016/j.jmb.2023.168415

Experimental method

ELECTRON MICROSCOPY (3.5 Å)