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Yorodumi- EMDB-50632: Cryo-EM structure of the 'crown'less Bcs macrocomplex for E. coli... -
+Open data
-Basic information
Entry | Database: EMDB / ID: EMD-50632 | |||||||||
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Title | Cryo-EM structure of the 'crown'less Bcs macrocomplex for E. coli cellulose secretion in non-saturating c-di-GMP (local) | |||||||||
Map data | Deep EMhancer-sharpened cryo-EM map of the 'crown'less Bcs macrocomplex for cellulose secretion in E. coli in non-saturating c-di-GMP (local) | |||||||||
Sample |
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Keywords | Bacterial cellulose secretion / MEMBRANE PROTEIN | |||||||||
Function / homology | Function and homology information cellulose biosynthetic process / UDP-alpha-D-glucose metabolic process / cell division / plasma membrane Similarity search - Function | |||||||||
Biological species | Escherichia coli (E. coli) | |||||||||
Method | single particle reconstruction / cryo EM / Resolution: 3.37 Å | |||||||||
Authors | Anso I / Krasteva PV | |||||||||
Funding support | European Union, 1 items
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Citation | Journal: Nat Commun / Year: 2024 Title: Structural basis for synthase activation and cellulose modification in the E. coli Type II Bcs secretion system. Authors: Itxaso Anso / Samira Zouhir / Thibault Géry Sana / Petya Violinova Krasteva / Abstract: Bacterial cellulosic polymers constitute a prevalent class of biofilm matrix exopolysaccharides that are synthesized by several types of bacterial cellulose secretion (Bcs) systems, which include ...Bacterial cellulosic polymers constitute a prevalent class of biofilm matrix exopolysaccharides that are synthesized by several types of bacterial cellulose secretion (Bcs) systems, which include conserved cyclic diguanylate (c-di-GMP)-dependent cellulose synthase modules together with diverse accessory subunits. In E. coli, the biogenesis of phosphoethanolamine (pEtN)-modified cellulose relies on the BcsRQABEFG macrocomplex, encompassing inner-membrane and cytosolic subunits, and an outer membrane porin, BcsC. Here, we use cryogenic electron microscopy to shed light on the molecular mechanisms of BcsA-dependent recruitment and stabilization of a trimeric BcsG pEtN-transferase for polymer modification, and a dimeric BcsF-dependent recruitment of an otherwise cytosolic BcsERQ regulatory complex. We further demonstrate that BcsE, a secondary c-di-GMP sensor, can remain dinucleotide-bound and retain the essential-for-secretion BcsRQ partners onto the synthase even in the absence of direct c-di-GMP-synthase complexation, likely lowering the threshold for c-di-GMP-dependent synthase activation. Such activation-by-proxy mechanism could allow Bcs secretion system activity even in the absence of substantial intracellular c-di-GMP increase, and is reminiscent of other widespread synthase-dependent polysaccharide secretion systems where dinucleotide sensing and/or synthase stabilization are carried out by key co-polymerase subunits. | |||||||||
History |
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-Structure visualization
Supplemental images |
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-Downloads & links
-EMDB archive
Map data | emd_50632.map.gz | 419.3 MB | EMDB map data format | |
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Header (meta data) | emd-50632-v30.xml emd-50632.xml | 31.8 KB 31.8 KB | Display Display | EMDB header |
FSC (resolution estimation) | emd_50632_fsc.xml | 16.6 KB | Display | FSC data file |
Images | emd_50632.png | 58.5 KB | ||
Masks | emd_50632_msk_1.map | 476.8 MB | Mask map | |
Filedesc metadata | emd-50632.cif.gz | 9.4 KB | ||
Others | emd_50632_additional_1.map.gz emd_50632_half_map_1.map.gz emd_50632_half_map_2.map.gz | 224 MB 442.9 MB 442.9 MB | ||
Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-50632 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-50632 | HTTPS FTP |
-Validation report
Summary document | emd_50632_validation.pdf.gz | 748.8 KB | Display | EMDB validaton report |
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Full document | emd_50632_full_validation.pdf.gz | 748.3 KB | Display | |
Data in XML | emd_50632_validation.xml.gz | 25.8 KB | Display | |
Data in CIF | emd_50632_validation.cif.gz | 34.2 KB | Display | |
Arichive directory | https://ftp.pdbj.org/pub/emdb/validation_reports/EMD-50632 ftp://ftp.pdbj.org/pub/emdb/validation_reports/EMD-50632 | HTTPS FTP |
-Related structure data
Related structure data | 9fp0MC 9fmtC 9fmvC 9fmzC 9fnnC 9fo7C 9fp2C C: citing same article (ref.) M: atomic model generated by this map |
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Similar structure data | Similarity search - Function & homologyF&H Search |
-Links
EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
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Related items in Molecule of the Month |
-Map
File | Download / File: emd_50632.map.gz / Format: CCP4 / Size: 476.8 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||
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Annotation | Deep EMhancer-sharpened cryo-EM map of the 'crown'less Bcs macrocomplex for cellulose secretion in E. coli in non-saturating c-di-GMP (local) | ||||||||||||||||||||||||||||||||||||
Projections & slices | Image control
Images are generated by Spider. | ||||||||||||||||||||||||||||||||||||
Voxel size | X=Y=Z: 0.839 Å | ||||||||||||||||||||||||||||||||||||
Density |
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Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||
Details | EMDB XML:
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-Supplemental data
-Mask #1
File | emd_50632_msk_1.map | ||||||||||||
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Projections & Slices |
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Density Histograms |
-Additional map: Unsharpened cryo-EM map of the 'crown'less Bcs macrocomplex...
File | emd_50632_additional_1.map | ||||||||||||
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Annotation | Unsharpened cryo-EM map of the 'crown'less Bcs macrocomplex for cellulose secretion in E. coli in non-saturating c-di-GMP (local) | ||||||||||||
Projections & Slices |
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Density Histograms |
-Half map: Half-map of the 'crown'less Bcs macrocomplex for cellulose...
File | emd_50632_half_map_1.map | ||||||||||||
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Annotation | Half-map of the 'crown'less Bcs macrocomplex for cellulose secretion in E. coli in non-saturating c-di-GMP (local) | ||||||||||||
Projections & Slices |
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Density Histograms |
-Half map: Half-map of the 'crown'less Bcs macrocomplex for cellulose...
File | emd_50632_half_map_2.map | ||||||||||||
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Annotation | Half-map of the 'crown'less Bcs macrocomplex for cellulose secretion in E. coli in non-saturating c-di-GMP (local) | ||||||||||||
Projections & Slices |
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Density Histograms |
-Sample components
+Entire : Locally refined 'crown'less Bcs macrocomplex in non-saturating c-...
+Supramolecule #1: Locally refined 'crown'less Bcs macrocomplex in non-saturating c-...
+Macromolecule #1: Cyclic di-GMP binding protein BcsE
+Macromolecule #2: Cell division protein
+Macromolecule #3: Protein YhjR
+Macromolecule #4: Cellulose synthase catalytic subunit [UDP-forming]
+Macromolecule #5: Cellulose biosynthesis protein BcsG
+Macromolecule #6: Cyclic di-GMP-binding protein
+Macromolecule #7: Cellulose biosynthesis protein BcsF
+Macromolecule #8: 9,9'-[(2R,3R,3aS,5S,7aR,9R,10R,10aS,12S,14aR)-3,5,10,12-tetrahydr...
+Macromolecule #9: ADENOSINE-5'-TRIPHOSPHATE
+Macromolecule #10: MAGNESIUM ION
-Experimental details
-Structure determination
Method | cryo EM |
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Processing | single particle reconstruction |
Aggregation state | particle |
-Sample preparation
Concentration | 2 mg/mL |
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Buffer | pH: 8 Details: 120 mM NaCL 20 mM HEPES pH8 5 mM MgCl2 10 uM ApppCp 4 uM c-di-GMP 0.01% LM-NPG |
Grid | Model: UltrAuFoil R1.2/1.3 / Material: GOLD / Mesh: 300 / Support film - Material: GOLD / Support film - topology: HOLEY |
Vitrification | Cryogen name: ETHANE / Chamber humidity: 100 % / Chamber temperature: 277 K |
Details | Purified Bcs macrocomplex with stoichiometry BcsA-BcsB6-BcsR2-BcsQ2-BcsE2-BcsF2-BcsG3 |
-Electron microscopy
Microscope | FEI TITAN KRIOS |
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Specialist optics | Energy filter - Name: GIF Quantum LS / Energy filter - Slit width: 20 eV |
Image recording | Film or detector model: GATAN K3 (6k x 4k) / Number grids imaged: 2 / Number real images: 20022 / Average electron dose: 49.35 e/Å2 |
Electron beam | Acceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN |
Electron optics | Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD / Cs: 2.7 mm / Nominal defocus max: 2.1 µm / Nominal defocus min: 0.3 µm |
Sample stage | Cooling holder cryogen: NITROGEN |
Experimental equipment | Model: Titan Krios / Image courtesy: FEI Company |
+Image processing
-Atomic model buiding 1
Initial model |
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Refinement | Space: REAL / Protocol: FLEXIBLE FIT | ||||||||||||
Output model | PDB-9fp0: |