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The solution structure of an anti-CRISPR protein.

ABSTRACT: Bacterial CRISPR-Cas adaptive immune systems use small guide RNAs to protect against phage infection and invasion by foreign genetic elements. We previously demonstrated that a group of Pseudomonas aeruginosa phages encode anti-CRISPR proteins that inactivate the type I-F and I-E CRISPR-Cas systems using distinct mechanisms. Here, we present the three-dimensional structure of an anti-CRISPR protein and map a functional surface that is critical for its potent inhibitory activity. The interaction of the anti-CRISPR protein with the CRISPR-Cas complex through this functional surface is proposed to prevent the binding of target DNA.

SUBMITTER: Maxwell KL

PROVIDER: S-EPMC5062604 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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The solution structure of an anti-CRISPR protein.

Maxwell Karen L KL Garcia Bianca B Bondy-Denomy Joseph J Bona Diane D Hidalgo-Reyes Yurima Y Davidson Alan R AR

Nature communications 20161011

Bacterial CRISPR-Cas adaptive immune systems use small guide RNAs to protect against phage infection and invasion by foreign genetic elements. We previously demonstrated that a group of Pseudomonas aeruginosa phages encode anti-CRISPR proteins that inactivate the type I-F and I-E CRISPR-Cas systems using distinct mechanisms. Here, we present the three-dimensional structure of an anti-CRISPR protein and map a functional surface that is critical for its potent inhibitory activity. The interaction ...[more]

PMID: 27725669

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