| 1 | 11AO|1|B (rep) | | RNA (5'-R(*AP*AP*AP*A)-3') | synthetic construct | | | Crystal structure of mouse DXO in complex with the oligonucleotide pA5 with 5'phosphate in the product and substrate states | X-ray diffraction | 1.59 | 4 | 2026-06-10 |
| 2 | 7SOS|1|B | | RNA (5'-R(*AP*AP*AP*A)-3') | synthetic construct | | | LaM domain of human LARP1 in complex with AAAA RNA | X-ray diffraction | 1.25 | 4 | 2022-08-03 |
| 3 | 9U49|1|C | | cyclic tetra-adenosine monophosphate(cA4) | synthetic construct | | | crystal structure of Cdn1 in complex with cA4 | X-ray diffraction | 1.9 | 4 | 2026-02-04 |
| 4 | 6XL1|1|C | | cA4 | synthetic construct | | | crystal structure of cA4-activated Cad1(D294N) | X-ray diffraction | 1.95 | 4 | 2020-12-30 |
| 5 | 6SCE|1|B | | cyclic oligoadenylate | synthetic construct | | | Structure of a Type III CRISPR defence DNA nuclease activated by cyclic oligoadenylate | X-ray diffraction | 1.83 | 4 | 2020-02-19 |
| 6 | 8Q42|1|X | | Cyclic tetraadenosine monophosphate (cA4) | synthetic construct | | | Crystal structure of cA4-bound Can2 (E341A) in complex with oligo-A DNA | X-ray diffraction | 1.97 | 4 | 2023-11-22 |
| 7 | 6YUD|1|K | | cyclic tetra-adenylate (cA4) | synthetic construct | | | Structure of Csx3/Crn3 from Archaeoglobus fulgidus in complex with cyclic tetra-adenylate (cA4) | X-ray diffraction | 1.84 | 4 | 2020-08-19 |
| 8 | 6YUD|1|O | | cyclic tetra-adenylate (cA4) | synthetic construct | | | Structure of Csx3/Crn3 from Archaeoglobus fulgidus in complex with cyclic tetra-adenylate (cA4) | X-ray diffraction | 1.84 | 4 | 2020-08-19 |
| 9 | 6SCF|1|I | | cyclic oligoadenylate | synthetic construct | | | A viral anti-CRISPR subverts type III CRISPR immunity by rapid degradation of cyclic oligoadenylate | X-ray diffraction | 1.55 | 4 | 2019-10-30 |
| 10 | 6YUD|1|P | | cyclic tetra-adenylate (cA4) | synthetic construct | | | Structure of Csx3/Crn3 from Archaeoglobus fulgidus in complex with cyclic tetra-adenylate (cA4) | X-ray diffraction | 1.84 | 4 | 2020-08-19 |
| 11 | 6SCF|1|K | | cyclic oligoadenylate | synthetic construct | | | A viral anti-CRISPR subverts type III CRISPR immunity by rapid degradation of cyclic oligoadenylate | X-ray diffraction | 1.55 | 4 | 2019-10-30 |
| 12 | 6SCF|1|M | | cyclic oligoadenylate | synthetic construct | | | A viral anti-CRISPR subverts type III CRISPR immunity by rapid degradation of cyclic oligoadenylate | X-ray diffraction | 1.55 | 4 | 2019-10-30 |
| 13 | 6SCF|1|L | | cyclic oligoadenylate | synthetic construct | | | A viral anti-CRISPR subverts type III CRISPR immunity by rapid degradation of cyclic oligoadenylate | X-ray diffraction | 1.55 | 4 | 2019-10-30 |
| 14 | 6YUD|1|M | | cyclic tetra-adenylate (cA4) | synthetic construct | | | Structure of Csx3/Crn3 from Archaeoglobus fulgidus in complex with cyclic tetra-adenylate (cA4) | X-ray diffraction | 1.84 | 4 | 2020-08-19 |
| 15 | 8T65|1|C | | RNA (5'-R(P*AP*AP*AP*A)-3') | Nitrosococcus halophilus Nc 4 | | | cA4 bound Cam1 | X-ray diffraction | 2.09 | 4 | 2024-01-10 |
| 16 | 6YUD|1|Q | | cyclic tetra-adenylate (cA4) | synthetic construct | | | Structure of Csx3/Crn3 from Archaeoglobus fulgidus in complex with cyclic tetra-adenylate (cA4) | X-ray diffraction | 1.84 | 4 | 2020-08-19 |
| 17 | 8Q44|1|X | | Cyclic tetraadenosine monophosphate (cA4) | synthetic construct | | | Crystal structure of cA4-bound Can2 (E364R) in complex with oligo-T DNA | X-ray diffraction | 2.3 | 4 | 2023-11-22 |
| 18 | 8Q40|1|X | | Cyclic tetraadenosine monophosphate (cA4) | synthetic construct | | | Crystal structure of cA4 activated Can2 in complex with a cleaved DNA substrate | X-ray diffraction | 2.21 | 4 | 2023-11-22 |
| 19 | 8Q41|1|X | | Cyclic tetraadenosine monophosphate (cA4) | synthetic construct | | | Crystal structure of Can2 (E341A) bound to cA4 and TTTAAA ssDNA | X-ray diffraction | 2.38 | 4 | 2023-11-22 |
| 20 | 9YLX|1|I | | Cyclic tetraadenylate | synthetic construct | | | Cryo-EM structure of the CbCash filament bound to cA4 | Electron microscopy | 2.45 | 4 | 2026-04-29 |
| 21 | 9YLX|1|J | | Cyclic tetraadenylate | synthetic construct | | | Cryo-EM structure of the CbCash filament bound to cA4 | Electron microscopy | 2.45 | 4 | 2026-04-29 |
| 22 | 8Q43|1|X | | Cyclic tetraadenosine monophosphate (cA4) | synthetic construct | | | Crystal structure of cA4-bound Can2 (E341A) in complex with oligo-C DNA | X-ray diffraction | 2.28 | 4 | 2023-11-22 |
| 23 | 8QJK|1|C | | Cyclic tetraadenosine monophosphate (cA4) | synthetic construct | | | Structure of the cytoplasmic domain of csx23 from Vibrio cholera in complex with cyclic tetra-adenylate (cA4) | X-ray diffraction | 1.761 | 4 | 2024-08-07 |
| 24 | 8BAO|1|C | | Cyclic tetra-adenylate (cA4) | synthetic construct | | | Dysgonamonadaceae bacterium CRISPR ancillary nuclease 2 | X-ray diffraction | 2.06 | 4 | 2022-11-30 |
| 25 | 6WXQ|1|E | | cyclic tetraadenylate | synthetic construct | | | Crystal structure of CRISPR-associated transcription factor Csa3 complexed with cA4 | X-ray diffraction | 2.05 | 4 | 2021-11-17 |
| 26 | 6W11|1|C | | cA4 | Saccharolobus solfataricus | | | The structure of Sulfolobus solfataricus Csa3 in complex with cyclic tetraadenylate (cA4) | X-ray diffraction | 2.46 | 4 | 2021-03-10 |
| 27 | 6O6X|1|D | | Cyclic RNA cA4 | synthetic construct | | | Crystal structure of Csm6 W14A/E337A mutant in complex with cA4 by cocrystallization | X-ray diffraction | 2.11 | 4 | 2019-07-31 |
| 28 | 9JXX|1|X | | RNA (5'-R(P*AP*AP*AP*A)-3') | synthetic construct | | | Crystal structure of SiRe_0806 in complex with cA4 | X-ray diffraction | 2.5 | 4 | 2025-07-23 |
| 29 | 9JXX|1|Y | | RNA (5'-R(P*AP*AP*AP*A)-3') | synthetic construct | | | Crystal structure of SiRe_0806 in complex with cA4 | X-ray diffraction | 2.5 | 4 | 2025-07-23 |
| 30 | 7DID|1|C | | RNA (5'-R(*AP*AP*AP*A)-3') | Mycoplasma genitalium G37 | | | Mycoplasma genitalium RNase R in complex with ribose methylated single-stranded RNA | X-ray diffraction | 1.9 | 4 | 2021-03-17 |
| 31 | 4BA2|1|R | | 5'-R(*AP*AP*AP*AP)-3' | Saccharolobus solfataricus | | | Archaeal exosome (Rrp4-Rrp41(D182A)-Rrp42) bound to inorganic phosphate | X-ray diffraction | 2.5 | 4 | 2012-10-03 |
| 32 | 7BDV|1|F | | cyclic tetra-adenylate | synthetic construct | | | Structure of Can2 from Sulfobacillus thermosulfidooxidans in complex with cyclic tetra-adenylate (cA4) | X-ray diffraction | 2.02 | 4 | 2021-03-03 |
| 33 | 8B0R|1|D | | RNA (5'-R(P*AP*AP*AP*A)-3') | Sulfurihydrogenibium | | | Structure of the CalpL/cA4 complex | X-ray diffraction | 2.2 | 4 | 2022-11-16 |
| 34 | 9C69|1|C | | AAAA | Bacteroidales bacterium | | | The CRISPR associated CARF-adenosine deaminase, Cad1-CARF in the cA4 bound form | X-ray diffraction | 2.4 | 4 | 2024-10-30 |
| 35 | 7BDV|1|H | | cyclic tetra-adenylate | synthetic construct | | | Structure of Can2 from Sulfobacillus thermosulfidooxidans in complex with cyclic tetra-adenylate (cA4) | X-ray diffraction | 2.02 | 4 | 2021-03-03 |
| 36 | 6O6X|1|C | | Cyclic RNA cA4 | synthetic construct | | | Crystal structure of Csm6 W14A/E337A mutant in complex with cA4 by cocrystallization | X-ray diffraction | 2.11 | 4 | 2019-07-31 |
| 37 | 9YLX|1|L | | Cyclic tetraadenylate | synthetic construct | | | Cryo-EM structure of the CbCash filament bound to cA4 | Electron microscopy | 2.45 | 4 | 2026-04-29 |
| 38 | 6O7B|1|C | | Cyclic RNA cA4 | synthetic construct | | | Crystal structure of Csm1-Csm4 cassette in complex with cA4 | X-ray diffraction | 2.4 | 4 | 2019-07-31 |
| 39 | 9YLX|1|K | | Cyclic tetraadenylate | synthetic construct | | | Cryo-EM structure of the CbCash filament bound to cA4 | Electron microscopy | 2.45 | 4 | 2026-04-29 |
| 40 | 6O6V|1|C | | Cyclic RNA cA4 | synthetic construct | | | Crystal structure of Csm6 in complex with cA4 by soaking cA4 into Csm6 | X-ray diffraction | 2.35 | 4 | 2019-07-31 |
| 41 | 7YGL|1|C | | RNA (5'-R(*AP*AP*AP*(A23))-3') | synthetic construct | | | Crystal Structure of the ring nuclease Sso2081 from Saccharolobus solfataricus in complex with A4>p cleavage intermediate | X-ray diffraction | 2.5 | 4 | 2023-02-15 |
| 42 | 6O6V|1|D | | Cyclic RNA cA4 | synthetic construct | | | Crystal structure of Csm6 in complex with cA4 by soaking cA4 into Csm6 | X-ray diffraction | 2.35 | 4 | 2019-07-31 |
| 43 | 6O7B|1|D | | Cyclic RNA cA4 | synthetic construct | | | Crystal structure of Csm1-Csm4 cassette in complex with cA4 | X-ray diffraction | 2.4 | 4 | 2019-07-31 |
| 44 | 7Z55|1|CCC | | Cyclic RNA cA4 | synthetic construct | | | Crystal Structure of the Ring Nuclease 0455 from Sulfolobus islandicus (Sis0455) in complex with its substrate | X-ray diffraction | 1.664 | 4 | 2022-11-23 |