8WL6 | pdb_00008wl6

Structure of 1,3-beta-glucan synthase component FKS1

• PDB DOI: https://doi.org/10.2210/pdb8WL6/pdb
• EM Map EMD-37612: EMDB EMDataResource

• Classification: MEMBRANE PROTEIN
• Organism(s): Saccharomyces cerevisiae
• Mutation(s): No 
• Membrane Protein: Yes  PDBTMMemProtMD


• Deposited: 2023-09-29 Released: 2025-02-19 
• Deposition Author(s): Li, J.L., Zhu, A.Q., Liu, J.X., Dai, X.L., Wang, X., Yan, C.Y., Deng, D.
• Funding Organization(s): National Natural Science Foundation of China (NSFC)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.16 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Cryo-EM structure of the beta-1,3-glucan synthase FKS1-Rho1 complex.

Li, J., Liu, H., Li, J., Liu, J., Dai, X., Zhu, A., Xiao, Q., Qian, W., Li, H., Guo, L., Yan, C., Deng, D., Luo, Y., Wang, X.

(2025) Nat Commun 16: 2054-2054

• PubMed: 40021629 
• DOI: https://doi.org/10.1038/s41467-025-57152-7
• Primary Citation Related Structures: 
  8WL6, 8WLA


• PubMed Abstract: 
  

  β-1,3 Glucan synthase (GS) is essential for fungal cell wall biosynthesis. The GS holoenzyme comprises the glycosyltransferase FKS1 and its regulatory factor Rho1, a small GTPase. However, the mechanism by which Rho1 activates FKS1 in a GTP-dependent manner remains unclear. Here, we present two cryo-EM structures of FKS1, apo and in complex with Rho1. FKS1 adopts a cellulose synthase-like conformation. The interaction between Rho1 and FKS1 is enhanced in the presence of GTPγS. Rho1 is positioned within a pocket between the glycosyltransferase domain of FKS1 (GT domain) and the transmembrane helix spanning TM7-15. Comparison of the two structures reveals extensive conformational changes within FKS1. These alterations suggest that Rho1's GTP/GDP cycling may act as a molecular pump, promoting a dynamic transition between the resting and active states of FKS1. Notably, Rho1 triggers FKS1 conformational changes that may push the growing glucan chain into FKS1's transmembrane channel, thereby facilitating β-1,3-glucan elongation.

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Organizational Affiliation: 
• Department of Obstetrics, Key Laboratory of Birth Defects and Related Disease of Women and Children of MOE, State Key Laboratory of Biotherapy, West China Second Hospital, Sichuan University, Chengdu, China.
Frontiers Science Center for Synthetic Biology (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China.
State Key Laboratory of Synthetic Biology, Tianjin University, Tianjin, 300072, China.
State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.
Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201204, China.
Department of Obstetrics, Key Laboratory of Birth Defects and Related Disease of Women and Children of MOE, State Key Laboratory of Biotherapy, West China Second Hospital, Sichuan University, Chengdu, China. [e-mail].
NHC Key Laboratory of Chronobiology, Development and Related Diseases of Women and Children Key Laboratory of Sichuan Province, Sichuan University, Chengdu, China. [e-mail].
Frontiers Science Center for Synthetic Biology (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China. [e-mail].
State Key Laboratory of Synthetic Biology, Tianjin University, Tianjin, 300072, China. [e-mail].
Department of Obstetrics, Key Laboratory of Birth Defects and Related Disease of Women and Children of MOE, State Key Laboratory of Biotherapy, West China Second Hospital, Sichuan University, Chengdu, China. [e-mail].
NHC Key Laboratory of Chronobiology, Development and Related Diseases of Women and Children Key Laboratory of Sichuan Province, Sichuan University, Chengdu, China. [e-mail].

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors and generated by (software)

Biological Assembly Evidence: electron microscopy

Macromolecule Content 

• Total Structure Weight: 215.08 kDa 
• Atom Count: 11,922 
• Modeled Residue Count: 1,489 
• Deposited Residue Count: 1,876 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
1,3-beta-glucan synthase component FKS1	A	1,876	Saccharomyces cerevisiae	Mutation(s): 0  EC: 2.4.1.34 Membrane Entity: Yes
UniProt
Find proteins for P38631 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c)) Explore P38631  Go to UniProtKB:  P38631

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.16 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2025-02-19 
Deposition Author(s): Li, J.L., Zhu, A.Q., Liu, J.X., Dai, X.L., Wang, X., Yan, C.Y., Deng, D.

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Funding Organization	Location	Grant Number
National Natural Science Foundation of China (NSFC)	China	--

Revision History  

• Version 1.0: 2025-02-19
  Type: Initial release
  
• Version 1.1: 2025-03-12
  Changes: Data collection, Database references