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Widespread stop-codon recoding in bacteriophages may regulate translation of lytic genes.

ABSTRACT: Bacteriophages (phages) are obligate parasites that use host bacterial translation machinery to produce viral proteins. However, some phages have alternative genetic codes with reassigned stop codons that are predicted to be incompatible with bacterial translation systems. We analysed 9,422 phage genomes and found that stop-codon recoding has evolved in diverse clades of phages that infect bacteria present in both human and animal gut microbiota. Recoded stop codons are particularly over-represented in phage structural and lysis genes. We propose that recoded stop codons might function to prevent premature production of late-stage proteins. Stop-codon recoding has evolved several times in closely related lineages, which suggests that adaptive recoding can occur over very short evolutionary timescales.

SUBMITTER: Borges AL

PROVIDER: S-EPMC9197471 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Widespread stop-codon recoding in bacteriophages may regulate translation of lytic genes.

Borges Adair L AL Lou Yue Clare YC Sachdeva Rohan R Al-Shayeb Basem B Penev Petar I PI Jaffe Alexander L AL Lei Shufei S Santini Joanne M JM Banfield Jillian F JF

Nature microbiology 20220526 6

Bacteriophages (phages) are obligate parasites that use host bacterial translation machinery to produce viral proteins. However, some phages have alternative genetic codes with reassigned stop codons that are predicted to be incompatible with bacterial translation systems. We analysed 9,422 phage genomes and found that stop-codon recoding has evolved in diverse clades of phages that infect bacteria present in both human and animal gut microbiota. Recoded stop codons are particularly over-represe ...[more]

PMID: 35618772

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