Structural basis for retron co-option of anti-phage ATPase-nuclease.

ABSTRACT: Retrons have been recently identified as bacterial defense systems that employ a tripartite of reverse transcriptase, non-coding RNA (ncRNA) and its derived multi-copy single stranded DNA (msDNA) to sequester effector activity. Phage invasion activates retrons, triggering effector activity and inducing abortive infection and cell growth arrest. Ec78 differs from other retrons by leveraging the Septu defense system, a stand-alone ATPase-nuclease pair (PtuAB), by reshaping the phage sensing and molecular assembly processes of PtuAB. To elucidate how Ec78 hijacks PtuAB, we determined electron cryomicroscopy structures of Ec78 as well as the retron-displaced PtuAB. We show that the Ec78-associated ATPase, PtuA, acquired unique elements that enable its interactions with the reverse transcriptas

SUBMITTER: Wang B 

PROVIDER: S-EPMC12819146 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature