+Open data
-Basic information
Entry | Database: EMDB / ID: EMD-18691 | |||||||||
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Title | Apo ReChb | |||||||||
Map data | ||||||||||
Sample |
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Keywords | Cas / BIOSYNTHETIC PROTEIN / cryo-EM / ancestral sequence reconstruction / biotechnology | |||||||||
Biological species | synthetic construct (others) | |||||||||
Method | single particle reconstruction / cryo EM / Resolution: 3.33 Å | |||||||||
Authors | Lopez-Alonso JP / Ubarretxena-Belandia I / Tascon I | |||||||||
Funding support | 1 items
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Citation | Journal: Nat Biotechnol / Year: 2024 Title: A resurrected ancestor of Cas12a expands target access and substrate recognition for nucleic acid editing and detection. Authors: Ylenia Jabalera / Igor Tascón / Sara Samperio / Jorge P López-Alonso / Monika Gonzalez-Lopez / Ana M Aransay / Guillermo Abascal-Palacios / Chase L Beisel / Iban Ubarretxena-Belandia / Raul Perez-Jimenez / Abstract: The properties of Cas12a nucleases constrict the range of accessible targets and their applications. In this study, we applied ancestral sequence reconstruction (ASR) to a set of Cas12a orthologs ...The properties of Cas12a nucleases constrict the range of accessible targets and their applications. In this study, we applied ancestral sequence reconstruction (ASR) to a set of Cas12a orthologs from hydrobacteria to reconstruct a common ancestor, ReChb, characterized by near-PAMless targeting and the recognition of diverse nucleic acid activators and collateral substrates. ReChb shares 53% sequence identity with the closest Cas12a ortholog but no longer requires a T-rich PAM and can achieve genome editing in human cells at sites inaccessible to the natural FnCas12a or the engineered and PAM-flexible enAsCas12a. Furthermore, ReChb can be triggered not only by double-stranded DNA but also by single-stranded RNA and DNA targets, leading to non-specific collateral cleavage of all three nucleic acid substrates with similar efficiencies. Finally, tertiary and quaternary structures of ReChb obtained by cryogenic electron microscopy reveal the molecular details underlying its expanded biophysical activities. Overall, ReChb expands the application space of Cas12a nucleases and underscores the potential of ASR for enhancing CRISPR technologies. | |||||||||
History |
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-Structure visualization
Supplemental images |
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-Downloads & links
-EMDB archive
Map data | emd_18691.map.gz | 117.8 MB | EMDB map data format | |
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Header (meta data) | emd-18691-v30.xml emd-18691.xml | 20.4 KB 20.4 KB | Display Display | EMDB header |
FSC (resolution estimation) | emd_18691_fsc.xml | 10.6 KB | Display | FSC data file |
Images | emd_18691.png | 126 KB | ||
Masks | emd_18691_msk_1.map | 125 MB | Mask map | |
Filedesc metadata | emd-18691.cif.gz | 7.1 KB | ||
Others | emd_18691_half_map_1.map.gz emd_18691_half_map_2.map.gz | 115.9 MB 115.9 MB | ||
Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-18691 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-18691 | HTTPS FTP |
-Validation report
Summary document | emd_18691_validation.pdf.gz | 871 KB | Display | EMDB validaton report |
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Full document | emd_18691_full_validation.pdf.gz | 870.6 KB | Display | |
Data in XML | emd_18691_validation.xml.gz | 19 KB | Display | |
Data in CIF | emd_18691_validation.cif.gz | 24.5 KB | Display | |
Arichive directory | https://ftp.pdbj.org/pub/emdb/validation_reports/EMD-18691 ftp://ftp.pdbj.org/pub/emdb/validation_reports/EMD-18691 | HTTPS FTP |
-Related structure data
Related structure data | 8qwdMC 8qweC 8qwfC C: citing same article (ref.) M: atomic model generated by this map |
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-Links
EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
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-Map
File | Download / File: emd_18691.map.gz / Format: CCP4 / Size: 125 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||
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Projections & slices | Image control
Images are generated by Spider. | ||||||||||||||||||||||||||||||||||||
Voxel size | X=Y=Z: 0.8238 Å | ||||||||||||||||||||||||||||||||||||
Density |
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Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||
Details | EMDB XML:
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-Supplemental data
-Mask #1
File | emd_18691_msk_1.map | ||||||||||||
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Projections & Slices |
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Density Histograms |
-Half map: #2
File | emd_18691_half_map_1.map | ||||||||||||
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Projections & Slices |
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Density Histograms |
-Half map: #1
File | emd_18691_half_map_2.map | ||||||||||||
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Projections & Slices |
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Density Histograms |
-Sample components
-Entire : Apo ReChb
Entire | Name: Apo ReChb |
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Components |
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-Supramolecule #1: Apo ReChb
Supramolecule | Name: Apo ReChb / type: complex / ID: 1 / Parent: 0 / Macromolecule list: #1 |
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Source (natural) | Organism: synthetic construct (others) |
-Macromolecule #1: ReChb
Macromolecule | Name: ReChb / type: protein_or_peptide / ID: 1 / Number of copies: 1 / Enantiomer: LEVO |
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Source (natural) | Organism: synthetic construct (others) |
Molecular weight | Theoretical: 148.954109 KDa |
Recombinant expression | Organism: Escherichia coli BL21(DE3) (bacteria) |
Sequence | String: GPKMFSNFTN QYPLSKTLRF ELKPVGKTLE HIEKKGLLEQ DEKRAEDYKK VKKIIDEYHK DFIEEALNNV KLNGEGLEEY YELYFKKNK DDKDKKKKEF EKIQDNLRKQ IVEAFKNHEK YKNLFKKELI KEDLPNWLKN SEDTGEEDKE TVEKFKNFTT Y FTGFHENR ...String: GPKMFSNFTN QYPLSKTLRF ELKPVGKTLE HIEKKGLLEQ DEKRAEDYKK VKKIIDEYHK DFIEEALNNV KLNGEGLEEY YELYFKKNK DDKDKKKKEF EKIQDNLRKQ IVEAFKNHEK YKNLFKKELI KEDLPNWLKN SEDTGEEDKE TVEKFKNFTT Y FTGFHENR KNMYSDEEKS TAIAYRLIHE NLPKFLDNMK VFEKIKEKHP EAEQLEKTLK DLGEEEVLGG NNVEDIFSLD YF NHTLTQS GIDIYNTIIG GKTEEDGNKK IQGLNEYINL YRQKNNEKNR KLPKLKPLYK QILSDRESLS FIPEAFENDE ELL EAIEEF YENLNFSNNN EATNVLEKLK ELLSNLADYD LNKIYIRNDT SLTDISQKIF GDWSVIKDAL NAHYDQTYPK KKKK KSKEK LEEKREKWLK KQKYFSIAEL QEALDSYCKE SDESKEQKEN SIADYFKTLA QTKNETDKKT DLIENIKSKY QYPND KKLA QDKEFKDVEK IKAFLDSIMN LQHFVKPLHL VKGGSAGAEM EKDEAFYSEF EALYEELSQV IPLYNKVRNY LTQKPY STE KIKLNFENST LLDGWDVNKE TDNTSVLLRK DGLYYLGIMN KKHNKVFENI PESNENDKCY EKMDYKLLPG ANKMLPK VF FSNKNIDYFN PSAEILEIYE NGTHKKSGDN FNLDDCHKLI DFFKESINKH EDWKKFGFKF SPTSSYEDIS GFYREVEQ Q GYKISFKNIS ESYIDELVDE GKLYLFQIYN KDFSPYSKGK PNLHTLYWKA LFDEENLKDV VYKLNGEAEV FYRKASINE TIVHKANEPI KNKNPLNPKK QSTFEYDIIK DRRYTVDKFQ FHVPITMNFK AEGNSNINDE VNEFLKGNAP DVNIIGIDRG ERHLLYLTL IDQKGKIVEQ DSLNTITNEH NETDYHALLD DKEKERDKAR KSWGTIENIK ELKEGYLSQV VHKIAKLMVE H NAIVVMED LNFGFKRGRF KVEKQVYQKF EKMLIDKLNY LVDKDKEPNE PGGLLNAYQL TNKFESFQKM GKQSGFLFYV PA WNTSKID PTTGFVNLFH PRYENVEKAK EFFNKFDSIR YNSEKDYFEF AFDYNNFTEK AEGTKWTVCT YGERIKTYRN ADK NNQWDS KEVNVTEEFK NLFDEYNIDY KNGNDLKEAI LSQDDADFFK SLLHLLRLTL QMRNSITGTE IDYIISPVAN ENGE FFDSR KADESLPKDA DANGAYHIAR KGLWVLEQIK QTDDLKKVNL AISNKEWLEF VQERKN |
-Macromolecule #2: MAGNESIUM ION
Macromolecule | Name: MAGNESIUM ION / type: ligand / ID: 2 / Number of copies: 2 / Formula: MG |
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Molecular weight | Theoretical: 24.305 Da |
-Macromolecule #3: water
Macromolecule | Name: water / type: ligand / ID: 3 / Number of copies: 4 / Formula: HOH |
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Molecular weight | Theoretical: 18.015 Da |
Chemical component information | ChemComp-HOH: |
-Experimental details
-Structure determination
Method | cryo EM |
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Processing | single particle reconstruction |
Aggregation state | particle |
-Sample preparation
Concentration | 2.5 mg/mL | |||||||||||||||
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Buffer | pH: 7.5 Component:
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Grid | Model: Quantifoil R1.2/1.3 / Material: COPPER / Mesh: 300 / Support film - Material: CARBON / Support film - topology: HOLEY | |||||||||||||||
Vitrification | Cryogen name: ETHANE / Chamber humidity: 95 % / Instrument: LEICA EM GP |
-Electron microscopy
Microscope | FEI TITAN KRIOS |
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Specialist optics | Energy filter - Name: GIF Bioquantum / Energy filter - Slit width: 20 eV |
Image recording | Film or detector model: GATAN K3 BIOQUANTUM (6k x 4k) / Number real images: 14874 / Average exposure time: 2.1 sec. / Average electron dose: 49.8 e/Å2 |
Electron beam | Acceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN |
Electron optics | C2 aperture diameter: 50.0 µm / Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD / Cs: 2.7 mm / Nominal defocus max: 1.6 µm / Nominal defocus min: 1.0 µm / Nominal magnification: 105000 |
Sample stage | Specimen holder model: FEI TITAN KRIOS AUTOGRID HOLDER / Cooling holder cryogen: NITROGEN |
Experimental equipment | Model: Titan Krios / Image courtesy: FEI Company |
+Image processing
-Atomic model buiding 1
Initial model | Chain - Source name: Other / Chain - Initial model type: other / Details: ModelAngelo |
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Refinement | Space: REAL / Protocol: FLEXIBLE FIT |
Output model | PDB-8qwd: |