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Phage single-stranded DNA-binding protein or host DNA damage triggers the activation of the AbpAB phage defense system.

ABSTRACT:

Importance

Although numerous phage defense systems have recently been discovered in bacteria, how these systems defend against phage propagation or sense phage infections remains unclear. The Escherichia coli AbpAB defense system targets several lytic and lysogenic phages harboring DNA genomes. A phage-encoded single-stranded DNA-binding protein, Gp32, activates this system similar to other phage defense systems such as Retron-Eco8, Hachiman, ShosTA, Nhi, and Hna. DNA replication inhibitors or defects in DNA repair factors activate the AbpAB system, even without phage infection. This is one of the few examples of activating phage defense systems without phage infection or proteins. The AbpAB defense system may be activated by sensing specific DNA-protein complexes.

SUBMITTER: Sasaki T

PROVIDER: S-EPMC10732053 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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Phage single-stranded DNA-binding protein or host DNA damage triggers the activation of the AbpAB phage defense system.

Sasaki Takaomi T Takita Saya S Fujishiro Takashi T Shintani Yunosuke Y Nojiri Satoki S Yasui Ryota R Yonesaki Tetsuro T Otsuka Yuichi Y

mSphere 20231026 6

<h4>Importance</h4>Although numerous phage defense systems have recently been discovered in bacteria, how these systems defend against phage propagation or sense phage infections remains unclear. The <i>Escherichia coli</i> AbpAB defense system targets several lytic and lysogenic phages harboring DNA genomes. A phage-encoded single-stranded DNA-binding protein, Gp32, activates this system similar to other phage defense systems such as Retron-Eco8, Hachiman, ShosTA, Nhi, and Hna. DNA replication ...[more]

PMID: 37882551

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