9EQQ | pdb_00009eqq

Uhgb_MS mannoside synthase from an unknown human gut bacterium in complex with Mannose

• PDB DOI: https://doi.org/10.2210/pdb9EQQ/pdb

• Classification: CARBOHYDRATE
• Organism(s): metagenome
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2024-03-22 Released: 2025-10-08 
• Deposition Author(s): Cioci, G., Ladeveze, S., Potocki-Veronese, G.
• Funding Organization(s): Not funded

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.55 Å
• R-Value Free: 
  0.207 (Depositor), 0.208 (DCC) 
• R-Value Work: 
  0.179 (Depositor), 0.187 (DCC) 

Starting Model: in silico

Literature

Dual-Activity Mannosyltransferase Phosphorylases in Family 130 of Glycoside Hydrolases.

Ladeveze, S., Tarquis, L., Cioci, G., Guieysse, D., Durand, J., Faure, R., Li, A., Esque, J., Vivier, M., Malbert, Y., Laville, E., Potocki-Veronese, G.

(2026) ACS Catal 16: 1211-1223

• PubMed: 41561435 
• DOI: https://doi.org/10.1021/acscatal.5c06782
• Primary Citation Related Structures: 
  9EQQ, 9FJ8, 9GPH


• PubMed Abstract: 
  

  We discovered that certain mannoside-active enzymes from family GH130 possess both glycoside phosphorylase (GP) and weak glycosyltransferase (GT) activities. This dual activity was observed only in glycoside phosphorylases acting on β-(1,2)- and β-(1,3)-mannosides, being absent in β-(1,4)-mannoside phosphorylases. We provide several three-dimensional (3D) structures of β-(1,2)-mannosyltransferase phosphorylases Uhgb_MS (identified from the human gut microbiome (subfamily GH130_4)) and Teth514_1788 (from Thermoanaerobacter sp. X514 (subfamily GH130_6)) and analyzed GT/GP partitioning among enzymes acting on d-mannosides. Structural analysis and mutagenesis of Uhgb_MS allowed us to show that loop L2 folding, as well as nucleotide and phosphate binding residues (P206, N211, R242) at the location of the common structural phosphate of αMan1P and GDP-Man, is an important structural element of bifunctionality in GH130.

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Organizational Affiliation: 
• TBI, Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France.
SweeTech SAS, 31077 Toulouse, France.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: gel filtration

Macromolecule Content 

• Total Structure Weight: 39.42 kDa 
• Atom Count: 2,909 
• Modeled Residue Count: 347 
• Deposited Residue Count: 350 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Uhgb_MS mannoside synthase from an unknown human gut bacterium	A	350	metagenome	Mutation(s): 0
UniProt
Find proteins for F0QZL2 (Phocaeicola salanitronis (strain DSM 18170 / JCM 13657 / CCUG 60908 / BL78)) Explore F0QZL2  Go to UniProtKB:  F0QZL2

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
MAN (Subject of Investigation/LOI)	B [auth A]	alpha-D-mannopyranose C6 H12 O6 WQZGKKKJIJFFOK-PQMKYFCFSA-N
EDO	C [auth A]	1,2-ETHANEDIOL C2 H6 O2 LYCAIKOWRPUZTN-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.55 Å
• R-Value Free:  0.207 (Depositor), 0.208 (DCC) 
• R-Value Work:  0.179 (Depositor), 0.187 (DCC) 

Space Group: P 6₁ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 176.629	α = 90
b = 176.629	β = 90
c = 83.539	γ = 120

Software Package:

Software Name	Purpose
REFMAC	refinement
XDS	data reduction
XDS	data scaling
MOLREP	phasing

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2025-10-08 
Deposition Author(s): Cioci, G., Ladeveze, S., Potocki-Veronese, G.

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Funding Organization	Location	Grant Number
Not funded		--

Revision History  

• Version 1.0: 2025-10-08
  Type: Initial release
  
• Version 1.1: 2026-09-30
  Changes: Database references