8G27

Hybrid aspen cellulose synthase-8 bound to UDP


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.30 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 2.0 of the entry. See complete history


Literature

Insights into substrate coordination and glycosyl transfer of poplar cellulose synthase-8.

Verma, P.Kwansa, A.L.Ho, R.Yingling, Y.G.Zimmer, J.

(2023) bioRxiv 

  • DOI: https://doi.org/10.1101/2023.02.07.527505
  • Primary Citation of Related Structures:  
    8G27, 8G2J

  • PubMed Abstract: 

    Cellulose is an abundant cell wall component of land plants. It is synthesized from UDP-activated glucose molecules by cellulose synthase, a membrane-integrated processive glycosyltransferase. Cellulose synthase couples the elongation of the cellulose polymer with its translocation across the plasma membrane. Here, we present substrate and product-bound cryogenic electron microscopy structures of the homotrimeric cellulose synthase isoform-8 (CesA8) from hybrid aspen (poplar). UDP-glucose binds to a conserved catalytic pocket adjacent to the entrance to a transmembrane channel. The substrate's glucosyl unit is coordinated by conserved residues of the glycosyltransferase domain and amphipathic interface helices. Site-directed mutagenesis of a conserved gating loop capping the active site reveals its critical function for catalytic activity. Molecular dynamics simulations reveal prolonged interactions of the gating loop with the substrate molecule, particularly across its central conserved region. These transient interactions likely facilitate the proper positioning of the substrate molecule for glycosyl transfer and cellulose translocation. Cryo-EM structures of substrate and product bound poplar cellulose synthase provide insights into substrate selectivitySite directed mutagenesis signifies a critical function of the gating loop for catalysisMolecular dynamics simulations support persistent gating loop - substrate interactionsGating loop helps in positioning the substrate molecule to facilitate cellulose elongationConserved cellulose synthesis substrate binding mechanism across the kingdoms.


  • Organizational Affiliation

    Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, 22903, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Cellulose synthaseA [auth D],
B [auth I],
C
991Populus tremula x Populus tremuloidesMutation(s): 0 
Gene Names: CesA3-1
EC: 2.4.1.12
Membrane Entity: Yes 
UniProt
Find proteins for Q6J8X0 (Populus tremula x Populus tremuloides)
Explore Q6J8X0 
Go to UniProtKB:  Q6J8X0
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ6J8X0
Sequence Annotations
Expand
  • Reference Sequence
Oligosaccharides

Help

Entity ID: 2
MoleculeChains Length2D Diagram Glycosylation3D Interactions
beta-D-glucopyranose-(1-4)-beta-D-glucopyranoseD [auth E],
E [auth A],
F [auth B]
2N/A
Glycosylation Resources
GlyTouCan:  G84824ZO
GlyCosmos:  G84824ZO
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.30 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Department of Energy (DOE, United States)United States--

Revision History  (Full details and data files)

  • Version 1.0: 2023-03-01
    Type: Initial release
  • Version 1.1: 2024-06-19
    Changes: Data collection
  • Version 2.0: 2024-08-21
    Changes: Advisory, Atomic model, Author supporting evidence, Data collection, Derived calculations, Non-polymer description, Refinement description, Structure summary