23DJ
anti-Crispr protein in apo form
Summary for 23DJ
| Entry DOI | 10.2210/pdb23dj/pdb |
| EMDB information | 68883 |
| Descriptor | anti-Crispr protein in apo form, NICKEL (II) ION (2 entities in total) |
| Functional Keywords | anti-crispr protein in apo form, cell invasion |
| Biological source | Pectobacterium araliae |
| Total number of polymer chains | 1 |
| Total formula weight | 125216.84 |
| Authors | |
| Primary citation | Sa, Y.,Liu, C.,Yang, L.,Yue, L.,Zhu, L.,Guo, Y.,Wang, R.,Wang, Y.,Feng, Y.,Wang, Y.,Zhang, Y.,Wang, W.,Xie, Y. Structural basis for dual mechanism of Cas2/3 nuclease inhibition by anti-CRISPR protein AcrIF19. Nat Commun, 17:-, 2026 Cited by PubMed Abstract: CRISPR-Cas systems are prokaryotic immune mechanisms often targeted by phage-encoded anti-CRISPR (Acr) proteins. This study characterizes AcrIF19, a potent inhibitor of the type I-F system in Pectobacterium atrosepticum. The cryo-EM structure of the apo Cas2/3 and Cas2/3-AcrIF19 complex reveals a dual inhibitory mechanism. AcrIF19 employs a negatively charged β-β loop to sterically occlude the non-target DNA strand entry channel, acting as a competitive inhibitor to disrupt Cas2/3 recruitment. Concurrently, this steric occlusion impedes ssDNA-mediated allosteric activation, which locks the critical helix-like loop motif in an inhibitory conformation and thereby abrogates DNA cleavage activity. AcrIF19 represents an anti-CRISPR protein inhibiting Cas2/3 via two different mechanisms, integrating a competitive ssDNA inhibitor with an allosteric blockade to suppress both target recruitment and DNA cleavage. PubMed: 42156407DOI: 10.1038/s41467-026-73156-3 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (2.55 Å) |
Structure validation
No wwPDB Validation report is currently available for this entry.
