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Open data
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Basic information
| Entry | ![]() | |||||||||
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| Title | Structure of human Apoferritin obtained from ssDNA coated grid | |||||||||
Map data | Final Map | |||||||||
Sample |
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Keywords | apoferritin / ssDNA covered grid / ssDNA / METAL BINDING PROTEIN | |||||||||
| Function / homology | Function and homology informationiron ion sequestering activity / ferritin complex / Scavenging by Class A Receptors / negative regulation of ferroptosis / Golgi Associated Vesicle Biogenesis / ferroxidase / autolysosome / ferroxidase activity / negative regulation of fibroblast proliferation / ferric iron binding ...iron ion sequestering activity / ferritin complex / Scavenging by Class A Receptors / negative regulation of ferroptosis / Golgi Associated Vesicle Biogenesis / ferroxidase / autolysosome / ferroxidase activity / negative regulation of fibroblast proliferation / ferric iron binding / autophagosome / iron ion transport / Iron uptake and transport / ferrous iron binding / tertiary granule lumen / ficolin-1-rich granule lumen / intracellular iron ion homeostasis / immune response / iron ion binding / negative regulation of cell population proliferation / Neutrophil degranulation / extracellular exosome / extracellular region / identical protein binding / nucleus / cytoplasm / cytosol Similarity search - Function | |||||||||
| Biological species | Homo sapiens (human) | |||||||||
| Method | single particle reconstruction / cryo EM / Resolution: 1.77 Å | |||||||||
Authors | Hrebik D / Plevka P | |||||||||
| Funding support | Czech Republic, 1 items
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Citation | Journal: Acta Crystallogr D Struct Biol / Year: 2022Title: Polyelectrolyte coating of cryo-EM grids improves lateral distribution and prevents aggregation of macromolecules. Authors: Dominik Hrebík / Mária Gondová / Lucie Valentová / Tibor Füzik / Antonín Přidal / Jiří Nováček / Pavel Plevka / ![]() Abstract: Cryo-electron microscopy (cryo-EM) is one of the primary methods used to determine the structures of macromolecules and their complexes. With the increased availability of cryo-electron microscopes, ...Cryo-electron microscopy (cryo-EM) is one of the primary methods used to determine the structures of macromolecules and their complexes. With the increased availability of cryo-electron microscopes, the preparation of high-quality samples has become a bottleneck in the cryo-EM structure-determination pipeline. Macromolecules can be damaged during the purification or preparation of vitrified samples for cryo-EM, making them prone to binding to the grid support, to aggregation or to the adoption of preferential orientations at the air-water interface. Here, it is shown that coating cryo-EM grids with a negatively charged polyelectrolyte, such as single-stranded DNA, before applying the sample reduces the aggregation of macromolecules and improves their distribution. The single-stranded DNA-coated grids enabled the determination of high-resolution structures from samples that aggregated on conventional grids. The polyelectrolyte coating reduces the diffusion of macromolecules and thus may limit the negative effects of the contact of macromolecules with the grid support and blotting paper, as well as of the shear forces on macromolecules during grid blotting. Coating grids with polyelectrolytes can readily be employed in any laboratory dealing with cryo-EM sample preparation, since it is fast, simple, inexpensive and does not require specialized equipment. | |||||||||
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Structure visualization
| Supplemental images |
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Downloads & links
-EMDB archive
| Map data | emd_14705.map.gz | 71.8 MB | EMDB map data format | |
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| Header (meta data) | emd-14705-v30.xml emd-14705.xml | 19.3 KB 19.3 KB | Display Display | EMDB header |
| FSC (resolution estimation) | emd_14705_fsc.xml | 18.1 KB | Display | FSC data file |
| Images | emd_14705.png | 82.6 KB | ||
| Filedesc metadata | emd-14705.cif.gz | 6.1 KB | ||
| Others | emd_14705_half_map_1.map.gz emd_14705_half_map_2.map.gz | 77.9 MB 77.9 MB | ||
| Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-14705 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-14705 | HTTPS FTP |
-Validation report
| Summary document | emd_14705_validation.pdf.gz | 1.3 MB | Display | EMDB validaton report |
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| Full document | emd_14705_full_validation.pdf.gz | 1.3 MB | Display | |
| Data in XML | emd_14705_validation.xml.gz | 20.7 KB | Display | |
| Data in CIF | emd_14705_validation.cif.gz | 27.9 KB | Display | |
| Arichive directory | https://ftp.pdbj.org/pub/emdb/validation_reports/EMD-14705 ftp://ftp.pdbj.org/pub/emdb/validation_reports/EMD-14705 | HTTPS FTP |
-Related structure data
| Related structure data | ![]() 7zg7MC ![]() 7ze1C ![]() 7zfwC M: atomic model generated by this map C: citing same article ( |
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| Similar structure data | Similarity search - Function & homology F&H Search |
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Links
| EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
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| Related items in Molecule of the Month |
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Map
| File | Download / File: emd_14705.map.gz / Format: CCP4 / Size: 83.7 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||
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| Annotation | Final Map | ||||||||||||||||||||||||||||||||||||
| Projections & slices | Image control
Images are generated by Spider. | ||||||||||||||||||||||||||||||||||||
| Voxel size | X=Y=Z: 0.4525 Å | ||||||||||||||||||||||||||||||||||||
| Density |
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| Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||
| Details | EMDB XML:
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-Supplemental data
-Half map: Half map 1
| File | emd_14705_half_map_1.map | ||||||||||||
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| Annotation | Half map 1 | ||||||||||||
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| Density Histograms |
-Half map: Half map 2
| File | emd_14705_half_map_2.map | ||||||||||||
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| Annotation | Half map 2 | ||||||||||||
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| Density Histograms |
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Sample components
-Entire : human heavy chain apoferritin
| Entire | Name: human heavy chain apoferritin |
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| Components |
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-Supramolecule #1: human heavy chain apoferritin
| Supramolecule | Name: human heavy chain apoferritin / type: complex / ID: 1 / Parent: 0 / Macromolecule list: #1 |
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| Source (natural) | Organism: Homo sapiens (human) |
| Molecular weight | Theoretical: 20 KDa |
-Macromolecule #1: Ferritin heavy chain
| Macromolecule | Name: Ferritin heavy chain / type: protein_or_peptide / ID: 1 / Number of copies: 24 / Enantiomer: LEVO / EC number: ferroxidase |
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| Source (natural) | Organism: Homo sapiens (human) |
| Molecular weight | Theoretical: 20.116547 KDa |
| Recombinant expression | Organism: ![]() |
| Sequence | String: TSQVRQNYHQ DSEAAINRQI NLELYASYVY LSMSYYFDRD DVALKNFAKY FLHQSHEERE HAEKLMKLQN QRGGRIFLQD IKKPDCDDW ESGLNAMECA LHLEKNVNQS LLELHKLATD KNDPHLCDFI ETHYLNEQVK AIKELGDHVT NLRKMGAPES G LAEYLFDK HTLG UniProtKB: Ferritin heavy chain |
-Macromolecule #2: ZINC ION
| Macromolecule | Name: ZINC ION / type: ligand / ID: 2 / Number of copies: 270 / Formula: ZN |
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| Molecular weight | Theoretical: 65.409 Da |
-Macromolecule #3: SODIUM ION
| Macromolecule | Name: SODIUM ION / type: ligand / ID: 3 / Number of copies: 112 |
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| Molecular weight | Theoretical: 22.99 Da |
-Macromolecule #4: water
| Macromolecule | Name: water / type: ligand / ID: 4 / Number of copies: 2680 / 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 |
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Sample preparation
| Concentration | 4.0 mg/mL | ||||||||||||
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| Buffer | pH: 7.5 Component:
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| Grid | Model: Quantifoil R2/2 / Material: COPPER / Mesh: 300 / Support film - Material: CARBON / Support film - topology: HOLEY / Support film - Film thickness: 5 / Pretreatment - Type: GLOW DISCHARGE / Pretreatment - Time: 10 sec. / Pretreatment - Atmosphere: NITROGEN | ||||||||||||
| Vitrification | Cryogen name: ETHANE / Chamber humidity: 100 % / Chamber temperature: 277.15 K / Instrument: FEI VITROBOT MARK IV Details: 6 s blot time,30 s waiting time, ssDNA covered grid. |
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Electron microscopy
| Microscope | FEI TITAN KRIOS |
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| Image recording | Film or detector model: FEI FALCON IV (4k x 4k) / Digitization - Dimensions - Width: 4096 pixel / Digitization - Dimensions - Height: 4096 pixel / Number grids imaged: 1 / Number real images: 3282 / Average exposure time: 4.08 sec. / Average electron dose: 40.0 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: 1.7 µm / Nominal defocus min: 0.3 µm / Nominal magnification: 130000 |
| Sample stage | Specimen holder model: FEI TITAN KRIOS AUTOGRID HOLDER / Cooling holder cryogen: NITROGEN |
| Experimental equipment | ![]() Model: Titan Krios / Image courtesy: FEI Company |
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About Yorodumi




Keywords
Homo sapiens (human)
Authors
Czech Republic, 1 items
Citation









Z (Sec.)
Y (Row.)
X (Col.)






































Processing
FIELD EMISSION GUN



