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Discovery of widespread type I and type V CRISPR-Cas inhibitors.

ABSTRACT: Bacterial CRISPR-Cas systems protect their host from bacteriophages and other mobile genetic elements. Mobile elements, in turn, encode various anti-CRISPR (Acr) proteins to inhibit the immune function of CRISPR-Cas. To date, Acr proteins have been discovered for type I (subtypes I-D, I-E, and I-F) and type II (II-A and II-C) but not other CRISPR systems. Here, we report the discovery of 12 acr genes, including inhibitors of type V-A and I-C CRISPR systems. AcrVA1 inhibits a broad spectrum of Cas12a (Cpf1) orthologs-including MbCas12a, Mb3Cas12a, AsCas12a, and LbCas12a-when assayed in human cells. The acr genes reported here provide useful biotechnological tools and mark the discovery of acr loci in many bacteria and phages.

SUBMITTER: Marino ND

PROVIDER: S-EPMC6520112 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Discovery of widespread type I and type V CRISPR-Cas inhibitors.

Marino Nicole D ND Zhang Jenny Y JY Borges Adair L AL Sousa Alexander A AA Leon Lina M LM Rauch Benjamin J BJ Walton Russell T RT Berry Joel D JD Joung J Keith JK Kleinstiver Benjamin P BP Bondy-Denomy Joseph J

Science (New York, N.Y.) 20180906 6411

Bacterial CRISPR-Cas systems protect their host from bacteriophages and other mobile genetic elements. Mobile elements, in turn, encode various anti-CRISPR (Acr) proteins to inhibit the immune function of CRISPR-Cas. To date, Acr proteins have been discovered for type I (subtypes I-D, I-E, and I-F) and type II (II-A and II-C) but not other CRISPR systems. Here, we report the discovery of 12 <i>acr</i> genes, including inhibitors of type V-A and I-C CRISPR systems. AcrVA1 inhibits a broad spectru ...[more]

PMID: 30190308

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