[English] 日本語
Yorodumi- PDB-8b7v: Automated simulation-based refinement of maltoporin into a cryo-E... -
+
Open data
-
Basic information
| Entry | Database: PDB / ID: 8b7v | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Title | Automated simulation-based refinement of maltoporin into a cryo-EM density | |||||||||
Components | Maltoporin | |||||||||
Keywords | MEMBRANE PROTEIN / maltoporin / density fit / automated refinement / cryo-em | |||||||||
| Function / homology | Function and homology informationmaltodextrin transmembrane transporter activity / maltose transporting porin activity / pore complex / monoatomic ion transport / cell outer membrane Similarity search - Function | |||||||||
| Biological species | ![]() | |||||||||
| Method | ELECTRON MICROSCOPY / single particle reconstruction / cryo EM / Resolution: 3 Å | |||||||||
Authors | Yvonnesdotter, L. / Rovsnik, U. / Blau, C. / Lycksell, M. / Howard, R.J. / Lindahl, E. | |||||||||
| Funding support | Sweden, 2items
| |||||||||
Citation | Journal: Biophys J / Year: 2023Title: Automated simulation-based membrane protein refinement into cryo-EM data. Authors: Linnea Yvonnesdotter / Urška Rovšnik / Christian Blau / Marie Lycksell / Rebecca Joy Howard / Erik Lindahl / ![]() Abstract: The resolution revolution has increasingly enabled single-particle cryogenic electron microscopy (cryo-EM) reconstructions of previously inaccessible systems, including membrane proteins-a category ...The resolution revolution has increasingly enabled single-particle cryogenic electron microscopy (cryo-EM) reconstructions of previously inaccessible systems, including membrane proteins-a category that constitutes a disproportionate share of drug targets. We present a protocol for using density-guided molecular dynamics simulations to automatically refine atomistic models into membrane protein cryo-EM maps. Using adaptive force density-guided simulations as implemented in the GROMACS molecular dynamics package, we show how automated model refinement of a membrane protein is achieved without the need to manually tune the fitting force ad hoc. We also present selection criteria to choose the best-fit model that balances stereochemistry and goodness of fit. The proposed protocol was used to refine models into a new cryo-EM density of the membrane protein maltoporin, either in a lipid bilayer or detergent micelle, and we found that results do not substantially differ from fitting in solution. Fitted structures satisfied classical model-quality metrics and improved the quality and the model-to-map correlation of the x-ray starting structure. Additionally, the density-guided fitting in combination with generalized orientation-dependent all-atom potential was used to correct the pixel-size estimation of the experimental cryo-EM density map. This work demonstrates the applicability of a straightforward automated approach to fitting membrane protein cryo-EM densities. Such computational approaches promise to facilitate rapid refinement of proteins under different conditions or with various ligands present, including targets in the highly relevant superfamily of membrane proteins. | |||||||||
| History |
|
-
Structure visualization
| Structure viewer | Molecule: Molmil Jmol/JSmol |
|---|
-
Downloads & links
-
Download
| PDBx/mmCIF format | 8b7v.cif.gz | 217.5 KB | Display | PDBx/mmCIF format |
|---|---|---|---|---|
| PDB format | pdb8b7v.ent.gz | 172.3 KB | Display | PDB format |
| PDBx/mmJSON format | 8b7v.json.gz | Tree view | PDBx/mmJSON format | |
| Others | Other downloads |
-Validation report
| Summary document | 8b7v_validation.pdf.gz | 1.3 MB | Display | wwPDB validaton report |
|---|---|---|---|---|
| Full document | 8b7v_full_validation.pdf.gz | 1.3 MB | Display | |
| Data in XML | 8b7v_validation.xml.gz | 41.9 KB | Display | |
| Data in CIF | 8b7v_validation.cif.gz | 65.3 KB | Display | |
| Arichive directory | https://data.pdbj.org/pub/pdb/validation_reports/b7/8b7v ftp://data.pdbj.org/pub/pdb/validation_reports/b7/8b7v | HTTPS FTP |
-Related structure data
| Related structure data | ![]() 15903MC M: map data used to model this data C: citing same article ( |
|---|---|
| Similar structure data | Similarity search - Function & homology F&H Search |
-
Links
-
Assembly
| Deposited unit | ![]()
|
|---|---|
| 1 |
|
-
Components
| #1: Protein | Mass: 47425.785 Da / Num. of mol.: 3 / Source method: isolated from a natural source / Source: (natural) ![]() Has protein modification | Y | |
|---|
-Experimental details
-Experiment
| Experiment | Method: ELECTRON MICROSCOPY |
|---|---|
| EM experiment | Aggregation state: PARTICLE / 3D reconstruction method: single particle reconstruction |
-
Sample preparation
| Component | Name: Trimeric maltoporin (LamB protein) / Type: COMPLEX / Entity ID: all / Source: NATURAL |
|---|---|
| Source (natural) | Organism: ![]() |
| Buffer solution | pH: 7.4 |
| Specimen | Conc.: 3 mg/ml / Embedding applied: NO / Shadowing applied: NO / Staining applied: NO / Vitrification applied: YES |
| Vitrification | Cryogen name: ETHANE |
-
Electron microscopy imaging
| Experimental equipment | ![]() Model: Titan Krios / Image courtesy: FEI Company |
|---|---|
| Microscopy | Model: FEI TITAN KRIOS |
| Electron gun | Electron source: FIELD EMISSION GUN / Accelerating voltage: 300 kV / Illumination mode: FLOOD BEAM |
| Electron lens | Mode: BRIGHT FIELD / Nominal defocus max: 2800 nm / Nominal defocus min: 1400 nm |
| Image recording | Electron dose: 42 e/Å2 / Detector mode: COUNTING / Film or detector model: GATAN K2 SUMMIT (4k x 4k) |
-
Processing
| CTF correction | Type: PHASE FLIPPING AND AMPLITUDE CORRECTION |
|---|---|
| 3D reconstruction | Resolution: 3 Å / Resolution method: FSC 0.143 CUT-OFF / Num. of particles: 579000 / Symmetry type: POINT |
Movie
Controller
About Yorodumi





Sweden, 2items
Citation
PDBj
microscopy
