7EI1

Structure of Pyrococcus furiosus Cas1Cas2 complex

Summary for 7EI1

• Entry DOI: 10.2210/pdb7ei1/pdb
• Descriptor: CRISPR-associated endonuclease Cas1, CRISPR-associated endoribonuclease Cas2 (2 entities in total)
• Functional Keywords: crispr, adaptation, immune system
• Biological source: Pyrococcus furiosus COM1; More
• Total number of polymer chains: 24
• Total formula weight: 680572.23

Authors

Yu, Y.,Chen, Q. (deposition date: 2021-03-30, release date: 2021-11-24, Last modification date: 2023-11-29)

Primary citation

Tang, D.,Li, H.,Wu, C.,Jia, T.,He, H.,Yao, S.,Yu, Y.,Chen, Q.
A distinct structure of Cas1-Cas2 complex provides insights into the mechanism for the longer spacer acquisition in Pyrococcus furiosus.
Int.J.Biol.Macromol., 183:379-386, 2021

PubMed Abstract: In the adaptation stage of CRISPR-Cas systems, the Cas1-Cas2 integrase captures and integrates new invader-derived spacers into the CRISPR locus, serving as a molecular memory of prior infection. As of yet, the structural information of Cas1-Cas2 complex is available only for two species. Here we present the crystal structure of Cas1-Cas2 complex of Pyrococcus furiosus, which showed a distinct architecture from the known Cas1-Cas2 complexes. The shorter C-terminal tail of Pfu Cas2 directs the Cas1 dimers go in the opposite direction, resulting in a different prespacer binding mode. Based on our structural and mutagenesis results, we modeled a prespacer with a shorter duplex and longer 3' overhangs to bind Pfu Cas1-Cas2 complex. The prespacer preference was confirmed by EMSA, fluorescence polarization, and in vitro integration assays. This model provides a potential explanation for the longer spacer acquisition observed in P. furiosus when deleting both cas4 genes. Our study highlights the diversity of the CRISPR adaptation module.

PubMed: 33864868
DOI: 10.1016/j.ijbiomac.2021.04.074

Experimental method

X-RAY DIFFRACTION (3.9 Å)