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High-resolution cryo-EM structure of the Pseudomonas bacteriophage E217.

ABSTRACT: E217 is a Pseudomonas phage used in an experimental cocktail to eradicate cystic fibrosis-associated Pseudomonas aeruginosa. Here, we describe the structure of the whole E217 virion before and after DNA ejection at 3.1 Å and 4.5 Å resolution, respectively, determined using cryogenic electron microscopy (cryo-EM). We identify and build de novo structures for 19 unique E217 gene products, resolve the tail genome-ejection machine in both extended and contracted states, and decipher the complete architecture of the baseplate formed by 66 polypeptide chains. We also determine that E217 recognizes the host O-antigen as a receptor, and we resolve the N-terminal portion of the O-antigen-binding tail fiber. We propose that E217 design principles presented in this paper are conserved across PB1-like Myoviridae phages of the Pbunavirus genus that encode a ~1.4 MDa baseplate, dramatically smaller than the coliphage T4.

SUBMITTER: Li F

PROVIDER: S-EPMC10329688 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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High-resolution cryo-EM structure of the Pseudomonas bacteriophage E217.

Li Fenglin F Hou Chun-Feng David CD Lokareddy Ravi K RK Yang Ruoyu R Forti Francesca F Briani Federica F Cingolani Gino G

Nature communications 20230708 1

E217 is a Pseudomonas phage used in an experimental cocktail to eradicate cystic fibrosis-associated Pseudomonas aeruginosa. Here, we describe the structure of the whole E217 virion before and after DNA ejection at 3.1 Å and 4.5 Å resolution, respectively, determined using cryogenic electron microscopy (cryo-EM). We identify and build de novo structures for 19 unique E217 gene products, resolve the tail genome-ejection machine in both extended and contracted states, and decipher the complete arc ...[more]

PMID: 37422479

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