Structural highlights
Function
Q9KR73_VIBCH
Publication Abstract from PubMed
Seventh-pandemic Vibrio cholerae strains contain two pathogenicity islands that encode the DNA defense modules DdmABC and DdmDE. In this study, we used cryogenic electron microscopy to determine the mechanistic basis for plasmid defense by DdmDE. The helicase-nuclease DdmD adopts an autoinhibited dimeric architecture. The prokaryotic Argonaute protein DdmE uses a DNA guide to target plasmid DNA. The structure of the DdmDE complex, validated by in vivo mutational studies, shows that DNA binding by DdmE triggers disassembly of the DdmD dimer and loading of monomeric DdmD onto the nontarget DNA strand. In vitro studies indicate that DdmD translocates in the 5'-to-3' direction, while partially degrading the plasmid DNA. These findings provide critical insights into the mechanism of DdmDE systems in plasmid elimination.
Molecular mechanism of plasmid elimination by the DdmDE defense system.,Loeff L, Adams DW, Chanez C, Stutzmann S, Righi L, Blokesch M, Jinek M Science. 2024 Jul 12;385(6705):188-194. doi: 10.1126/science.adq0534. Epub 2024 , Jun 13. PMID:38870273[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Loeff L, Adams DW, Chanez C, Stutzmann S, Righi L, Blokesch M, Jinek M. Molecular mechanism of plasmid elimination by the DdmDE defense system. Science. 2024 Jul 12;385(6705):188-194. PMID:38870273 doi:10.1126/science.adq0534