| Products/Services Used | Details | Operation |
|---|---|---|
| Gene Synthesis | The DNA sequence coding for full-length (residues 1−388) Pseudomonas syringae (Ps) Cap5 (TRN83959.1) was codon optimized for protein expression in Escherichia coli, and then synthesized and inserted between BamHI and HindIII cloning sites of a modified pET28b(+) vector (Novagen) to produce N-terminally tagged His6-SUMO (small ubiquitin-like modifier) fusion protein (GenScript). His56Ala substitution was introduced by site-directed mutagenesis of the PsCap5 expression plasmid (Genscript). | Get A Quote |
Bacterial CBASS immune defense systems commonly kill virally infected cells by degrading genomic DNA in a form of cell suicide or abortive infection. We present a high-resolution structure of the CBASS effector Cap5, activated by a cyclic nucleotide, in the act of digesting DNA via tetrameric HNH endonuclease domains. Two HNH domains are in a catalytically active state for cleavage of the DNA strands, whereas the other two HNH domains are in a topologically distinct catalytically inactive state for simply DNA binding. The four HNH domains track one face of the DNA and mark an enzyme that acts as a stand-alone non-specific nuclease. We also show that chromosomally encoded CBASS Cap5 can be extrinsically activate... More
