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CRISPR — a widespread system that provides acquired resistance against phages in bacteria and archaea


Arrays of clustered, regularly interspaced short palindromic repeats (CRISPRs) are widespread in the genomes of many bacteria and almost all archaea. These arrays are composed of direct repeats that are separated by similarly sized non-repetitive spacers. CRISPR arrays, together with a group of associated proteins, confer resistance to phages, possibly by an RNA-interference-like mechanism. This Progress discusses the structure and function of this newly recognized antiviral mechanism.

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Figure 1: CRISPR structure and function.
Figure 2: Applications of CRISPRs.


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The authors thank H. Garcia Martin, M. J. Blow, A. Visel and G. Tyson for helpful discussions. This work was performed under the auspices of the US Department of Energy, Office of Science, Biological and Environmental Research Program at the University of California, Lawrence Berkeley National Laboratory under contract No. DE-AC02-05CH11231, Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344 and Los Alamos National Laboratory under contract No. DE-AC02-06NA25396.

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Correspondence to Rotem Sorek.

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Entrez Genome Project

Campylobacter jejuni

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Sorek, R., Kunin, V. & Hugenholtz, P. CRISPR — a widespread system that provides acquired resistance against phages in bacteria and archaea. Nat Rev Microbiol 6, 181–186 (2008).

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