Cas4 is an endonuclease found in some

CRISPR CRISPR (; acronym of clustered regularly interspaced short palindromic repeats) is a family of DNA sequences found in the genomes of prokaryotic organisms such as bacteria and archaea. Each sequence within an individual prokaryotic CRISPR is d ...

systems that is used as part of the spacer acquisition stage. Geobacter sulfurreducens Cas1-Cas2-Cas4 complex PDB 7MI4

Cas4 is required for efficient prespacer processing by forming a Cas4-

Cas1 CRISPR-associated protein 1 (cas1) is one of the two universally conserved proteins found in the CRISPR prokaryotic immune defense system. Cas1 is a metal-dependent DNA-specific endonuclease that produces double-stranded DNA fragments. Cas1 forms ...

Cas2 Cas2 is a protein associated with CRISPR that is involved with spacer acquisition. Representative cas2 proteins have been characterized as endonucleases that cleave single-stranded RNAs preferentially within U-rich regions, or as metal-dependen ...

complex. In this complex, Cas4 cuts double-stranded substrates with long 3'-overhangs through site-specific endonucleolytic cleavage. Cas4 closely interacts with the integrase active sites of

, recognizes PAM sequences within the substrate and cleaves precisely upstream of them, ensuring the acquisition of functional spacers.

References

Enzymes {{enzyme-stub