Loop-extrusion-mediated plasmid DNA cleavage by the bacterial SMC Wadjet complex.

ABSTRACT: Structural maintenance of chromosomes (SMC) complexes play pivotal roles in genome organization and maintenance across all domains of life. In prokaryotes, SMC-family Wadjet complexes structurally resemble the widespread MukBEF but serve a defensive role by inhibiting plasmid transformation. We previously showed that Wadjet specifically cleaves plasmid DNA; however, the molecular mechanism underlying plasmid recognition remains unclear. Here, we use in vitro single-molecule imaging to directly visualize DNA loop extrusion and plasmid cleavage by Wadjet. We find that Wadjet is a symmetric loop extruder that simultaneously reels in DNA from both sides of a loop and that this activity requires a dimeric JetABC supercomplex. On surface-anchored plasmid DNAs, Wadjet extrudes the full length of

SUBMITTER: Pradhan B 

PROVIDER: S-EPMC12875379 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature