9NLG
CBASS Pseudomonas syringae Cap5 tetramer with 3'2'-c-GAMP cyclic dinucleotide ligand (His56Ala mutant without Mg2+ ions)
Summary for 9NLG
| Entry DOI | 10.2210/pdb9nlg/pdb |
| Related | 8FMG 8FMH 9DIF 9DIH |
| Descriptor | HNH endonuclease, ZINC ION, 3'2'-cGAMP, ... (5 entities in total) |
| Functional Keywords | bacterial immunity, cbass, cyclic dinucleotide, cap5 effector dna endonuclease, viral defense, dna, immune system |
| Biological source | Pseudomonas syringae |
| Total number of polymer chains | 4 |
| Total formula weight | 173860.05 |
| Authors | |
| Primary citation | Rechkoblit, O.,Sciaky, D.,Ni, M.,Li, Y.,Kottur, J.,Fang, G.,Aggarwal, A.K. Mechanism of DNA degradation by CBASS Cap5 endonuclease immune effector. Nat Commun, 16:5243-5243, 2025 Cited by PubMed Abstract: 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 activated by a cyclic nucleotide, as a step towards potential antibiotics. PubMed: 40473611DOI: 10.1038/s41467-025-60484-z PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.64 Å) |
Structure validation
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