The number and diversity of known CRISPR–Cas systems have substantially increased in
recent years. Here, we provide an updated evolutionary classification of CRISPR–Cas …

In bacteria and archaea, clustered regularly interspaced short palindromic repeats
(CRISPR) and CRISPR-associated (Cas) proteins constitute an adaptive immune system …

Automated classification of CRISPR-Cas systems has been challenged by their dynamic
nature and expanding classification. Here, we developed CRISPRCasTyper, an automated …

Evolution of bacteria and archaea involves an incessant arms race against an enormous
diversity of genetic parasites. Accordingly, a substantial fraction of the genes in most …

Some phages encode anti-CRISPR (acr) genes, which antagonize bacterial CRISPR-Cas
immune systems by binding components of its machinery, but it is less clear how …

Bacteria have a range of distinct immune strategies that provide protection against
bacteriophage (phage) infections. While much has been learned about the mechanism of …

Prokaryotic CRISPR-Cas adaptive immune systems insert spacers derived from viruses and
other parasitic DNA elements into CRISPR loci to provide sequence-specific immunity,. This …

Current understanding of microorganism–virus interactions, which shape the evolution and
functioning of Earth's ecosystems, is based primarily on cultivated organisms. Here we …

One of the most prominent features of archaea is the extraordinary diversity of their DNA
viruses. Many archaeal viruses differ substantially in morphology from bacterial and …

Clustered regularly interspaced short palindromic repeats and CRISPR-associated protein
(CRISPR-Cas) systems store the memory of past encounters with foreign DNA in unique …