+
Open data
-
Basic information
| Entry | ![]() | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Title | Cowpea chlorotic mottle virus in the contracted state | ||||||||||||
Map data | Sharpened | ||||||||||||
Sample |
| ||||||||||||
Keywords | cowpea chlorotic mottle virus / plant / VIRUS | ||||||||||||
| Biological species | Cowpea chlorotic mottle virus | ||||||||||||
| Method | single particle reconstruction / cryo EM / Resolution: 3.2 Å | ||||||||||||
Authors | Alexandrescu L / Lander GC | ||||||||||||
| Funding support | United States, 3 items
| ||||||||||||
Citation | Journal: IUCrJ / Year: 2025Title: `Mix-it-up': accessible time-resolved cryo-EM on the millisecond timescale. Authors: Lauren Alexandrescu / William Lessin / Gabriel C Lander / ![]() Abstract: Biological reactions often involve macromolecules that undergo substrate-induced conformational changes in under a second, yet capturing these transient states remains challenging. While high- ...Biological reactions often involve macromolecules that undergo substrate-induced conformational changes in under a second, yet capturing these transient states remains challenging. While high-resolution structural techniques such as X-ray crystallography and cryo-electron microscopy (cryo-EM) have advanced our mechanistic understanding of protein-substrate interactions, traditional sample-preparation methods are too slow to capture rapid biochemical events. Time-resolved cryo-EM has emerged as a promising approach to visualize structural dynamics on microsecond-to-millisecond timescales, but its widespread adoption has been limited by costly equipment and challenges in achieving rapid mixing, application and vitrification of samples in a reproducible manner. To address these limitations, we developed `Mix-it-up' (MIU), a modified spray device designed for rapid on-grid mixing and vitrification of cryo-EM samples. By manually applying one sample onto the EM grid, blotting and subsequently spraying the second sample, we achieve on-grid mixing with a vitrification delay of as low as ∼120 ms. We demonstrate MIU's time-resolved capabilities through high-resolution structure determination of mixed samples, pH-induced viral capsid contraction and ligand-dependent complex formation. These findings establish MIU as a cost-effective, versatile tool for studying rapid biochemical processes and lay the groundwork for future applications to time-resolved cryo-EM. | ||||||||||||
| History |
|
-
Structure visualization
| Supplemental images |
|---|
-
Downloads & links
-EMDB archive
| Map data | emd_70749.map.gz | 450.9 MB | EMDB map data format | |
|---|---|---|---|---|
| Header (meta data) | emd-70749-v30.xml emd-70749.xml | 22.7 KB 22.7 KB | Display Display | EMDB header |
| FSC (resolution estimation) | emd_70749_fsc.xml | 16.5 KB | Display | FSC data file |
| Images | emd_70749.png | 115.3 KB | ||
| Masks | emd_70749_msk_1.map | 476.8 MB | Mask map | |
| Filedesc metadata | emd-70749.cif.gz | 5.6 KB | ||
| Others | emd_70749_additional_1.map.gz emd_70749_half_map_1.map.gz emd_70749_half_map_2.map.gz | 238.4 MB 441.7 MB 441.7 MB | ||
| Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-70749 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-70749 | HTTPS FTP |
-Related structure data
-
Links
| EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
|---|
-
Map
| File | Download / File: emd_70749.map.gz / Format: CCP4 / Size: 476.8 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Annotation | Sharpened | ||||||||||||||||||||||||||||||||||||
| Projections & slices | Image control
Images are generated by Spider. | ||||||||||||||||||||||||||||||||||||
| Voxel size | X=Y=Z: 0.94 Å | ||||||||||||||||||||||||||||||||||||
| Density |
| ||||||||||||||||||||||||||||||||||||
| Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||
| Details | EMDB XML:
|
-Supplemental data
-Mask #1
| File | emd_70749_msk_1.map | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Projections & Slices |
| ||||||||||||
| Density Histograms |
-Additional map: Unsharpened
| File | emd_70749_additional_1.map | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Annotation | Unsharpened | ||||||||||||
| Projections & Slices |
| ||||||||||||
| Density Histograms |
-Half map: #2
| File | emd_70749_half_map_1.map | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Projections & Slices |
| ||||||||||||
| Density Histograms |
-Half map: #1
| File | emd_70749_half_map_2.map | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Projections & Slices |
| ||||||||||||
| Density Histograms |
-
Sample components
-Entire : Cowpea chlorotic mottle virus
| Entire | Name: Cowpea chlorotic mottle virus |
|---|---|
| Components |
|
-Supramolecule #1: Cowpea chlorotic mottle virus
| Supramolecule | Name: Cowpea chlorotic mottle virus / type: virus / ID: 1 / Parent: 0 / Macromolecule list: all / NCBI-ID: 12303 / Sci species name: Cowpea chlorotic mottle virus / Virus type: VIRION / Virus isolate: SPECIES / Virus enveloped: No / Virus empty: No |
|---|---|
| Host (natural) | Organism: Vigna unguiculata subsp. unguiculata (cowpea) / Strain: No. 5 |
| Molecular weight | Theoretical: 3.8 MDa |
| Virus shell | Shell ID: 1 / Name: Capsid / Diameter: 290.0 Å / T number (triangulation number): 3 |
-Macromolecule #1: Cowpea chlorotic mottle virus capsid
| Macromolecule | Name: Cowpea chlorotic mottle virus capsid / type: protein_or_peptide / ID: 1 / Enantiomer: LEVO |
|---|---|
| Source (natural) | Organism: Cowpea chlorotic mottle virus |
| Sequence | String: MSTVGTGKLT RAQRRAAARK NKRNTRVVQP VIVEPIASGQ GKAIKAWTGY SVSKWTASCA AAEAKVTSAI TISLPNELSS ERNKQLKVGR VLLWLGLLPS VSGTVKSCVT ETQTTAAASF QVALAVADNS KDVVAAMYPE AFKGITLEQL TADLTIYLYS SAALTEGDVI VHLEVEHVRP TFDDSFTPVY |
-Experimental details
-Structure determination
| Method | cryo EM |
|---|---|
Processing | single particle reconstruction |
| Aggregation state | particle |
-
Sample preparation
| Concentration | 11 mg/mL | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Buffer | pH: 4.8 Component:
| |||||||||
| Grid | Model: Homemade / Material: COPPER/RHODIUM / Mesh: 400 / Support film - Material: GOLD / Support film - topology: HOLEY / Support film - Film thickness: 35 / Pretreatment - Type: PLASMA CLEANING / Pretreatment - Time: 7 sec. / Pretreatment - Atmosphere: OTHER / Pretreatment - Pressure: 23.998 kPa | |||||||||
| Vitrification | Cryogen name: ETHANE / Chamber humidity: 69 % / Chamber temperature: 296 K Details: Vitrification performed at ambient humidity and room temperature using specialized "Mix-it-Up" electrospray device. |
-
Electron microscopy
| Microscope | FEI TALOS ARCTICA |
|---|---|
| Temperature | Min: 70.0 K / Max: 77.0 K |
| Image recording | Film or detector model: TFS FALCON 4i (4k x 4k) / Digitization - Dimensions - Width: 4096 pixel / Digitization - Dimensions - Height: 4096 pixel / Number real images: 292 / Average exposure time: 4.13 sec. / Average electron dose: 50.0 e/Å2 |
| Electron beam | Acceleration voltage: 200 kV / Electron source: FIELD EMISSION GUN |
| Electron optics | C2 aperture diameter: 30.0 µm / Calibrated defocus max: 3.1270000000000002 µm / Calibrated defocus min: 0.1 µm / Calibrated magnification: 148936 / Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD / Cs: 2.7 mm / Nominal defocus max: 1.4000000000000001 µm / Nominal defocus min: 1.0 µm / Nominal magnification: 150000 |
| Sample stage | Specimen holder model: FEI TITAN KRIOS AUTOGRID HOLDER / Cooling holder cryogen: NITROGEN |
| Experimental equipment | ![]() Model: Talos Arctica / Image courtesy: FEI Company |
Movie
Controller
About Yorodumi




Cowpea chlorotic mottle virus
Keywords
Authors
United States, 3 items
Citation






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




















































Vigna unguiculata subsp. unguiculata (cowpea)
Processing
FIELD EMISSION GUN

