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7ofh

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CryoEM structure of the outer membrane secretin pore pIV from the f1 filamentous bacteriophage.

Structural highlights

7ofh is a 15 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[G4P_BPF1] Acts in the assembly and extrusion of the bacteriophage by forming a channel across the host outer membrane. This channel is just large enough to allow a newly synthesized phage particle to pass through. Extrusion is a process of concomitant assembly and secretion and takes place at specific assembly sites where host inner and outer membranes are in close contacts.

Publication Abstract from PubMed

The Ff family of filamentous bacteriophages infect gram-negative bacteria, but do not cause lysis of their host cell. Instead, new virions are extruded via the phage-encoded pIV protein, which has homology with bacterial secretins. Here, we determine the structure of pIV from the f1 filamentous bacteriophage at 2.7 A resolution by cryo-electron microscopy, the first near-atomic structure of a phage secretin. Fifteen f1 pIV subunits assemble to form a gated channel in the bacterial outer membrane, with associated soluble domains projecting into the periplasm. We model channel opening and propose a mechanism for phage egress. By single-cell microfluidics experiments, we demonstrate the potential for secretins such as pIV to be used as adjuvants to increase the uptake and efficacy of antibiotics in bacteria. Finally, we compare the f1 pIV structure to its homologues to reveal similarities and differences between phage and bacterial secretins.

CryoEM structure of the outer membrane secretin channel pIV from the f1 filamentous bacteriophage.,Conners R, McLaren M, Lapinska U, Sanders K, Stone MRL, Blaskovich MAT, Pagliara S, Daum B, Rakonjac J, Gold VAM Nat Commun. 2021 Nov 2;12(1):6316. doi: 10.1038/s41467-021-26610-3. PMID:34728631^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Conners R, McLaren M, Lapinska U, Sanders K, Stone MRL, Blaskovich MAT, Pagliara S, Daum B, Rakonjac J, Gold VAM. CryoEM structure of the outer membrane secretin channel pIV from the f1 filamentous bacteriophage. Nat Commun. 2021 Nov 2;12(1):6316. doi: 10.1038/s41467-021-26610-3. PMID:34728631 doi:http://dx.doi.org/10.1038/s41467-021-26610-3