DNA restriction-modification enzymes articles from across Nature Portfolio

The authors propose a model for the mechanism underlying how a phage defence system remains primed for infection but tightly controlled to prevent host toxicity.

Here, using single-molecule experiments, the authors show that SpCas9 responds to shifted PAMs by inducing overhanging DNA ends. Such shift-PAM targeting is enhanced by physiological levels of DNA supercoiling and in turn promotes dissociation of the complex after catalysis.

DNA mutations occurring at low frequencies can be more easily detected by first excising wild-type DNA strands via the endonuclease deoxyribonuclease I, guided by single-stranded phosphorothioated DNA.

By leveraging structural and biochemical methods, the authors show that the interbacterial deaminase toxin DddA, a potential gene-editing tool, uses a tandem displacement mechanism to catalyze cytosine-to-uracil conversion in double-stranded DNA.

Here, using plasmonic DNA origami nanorotors, the authors observe in real time the R-loop formation and locking by the clustered regularly interspaced short palindromic repeats–Cas surveillance complex Cascade, thus reconstructing the underlying energy landscape and dynamics of this process.

Programmable, RNA-guided nucleases are diverse enzymes that have been repurposed for biotechnological applications. Here, the authors mine an extensive genome-resolved metagenomics database and identified uncharacterized families of RNA-guided, compact nucleases.

Single-molecule, real-time sequencing shows that a phase variation-induced epigenetic switch controls colony morphology inStreptococcus pneumoniae.