6KDV

Crystal structure of TtCas1-DNA complex

Summary for 6KDV

• Entry DOI: 10.2210/pdb6kdv/pdb
• Descriptor: CRISPR-associated endonuclease Cas1 2, DNA (5'-D(*GP*AP*GP*TP*CP*GP*AP*TP*GP*CP*TP*GP*GP*TP*TP*TP*TP*TP*TP*TP*TP*TP*T)-3'), DNA (5'-D(*TP*TP*TP*TP*TP*TP*TP*TP*TP*TP*CP*CP*AP*GP*CP*AP*TP*CP*GP*AP*CP*TP*C)-3') (3 entities in total)
• Functional Keywords: crispr, cas1, dna binding protein, dna binding protein-dna complex, dna binding protein/dna
• Biological source: Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579); More
• Total number of polymer chains: 8
• Total formula weight: 172054.89

Authors

Wang, Y.L.,Li, J.Z.,Yang, J.,Wang, J.Y. (deposition date: 2019-07-02, release date: 2019-12-18, Last modification date: 2024-11-06)

Primary citation

Yang, J.,Li, J.,Wang, J.,Sheng, G.,Wang, M.,Zhao, H.,Yang, Y.,Wang, Y.
Crystal structure of Cas1 in complex with branched DNA.
Sci China Life Sci, 63:516-528, 2020

PubMed Abstract: Cas1 is a key component of the CRISPR adaptation complex, which captures and integrates foreign DNA into the CRISPR array, resulting in the generation of new spacers. We have determined crystal structures of Thermus thermophilus Cas1 involved in new spacer acquisition both in complex with branched DNA and in the free state. Cas1 forms an asymmetric dimer without DNA. Conversely, two asymmetrical dimers bound to two branched DNAs result in the formation of a DNA-mediated tetramer, dimer of structurally asymmetrical dimers, in which the two subunits markedly present different conformations. In the DNA binding complex, the N-terminal domain adopts different orientations with respect to the C-terminal domain in the two monomers that form the dimer. Substrate binding triggers a conformational change in the loop 164-177 segment. This loop is also involved in the 3' fork arm and 5' fork arm strand recognition in monomer A and B, respectively. This study provides important insights into the molecular mechanism of new spacer adaptation.

PubMed: 31792780
DOI: 10.1007/s11427-019-9827-x

Experimental method

X-RAY DIFFRACTION (3.11 Å)