Crystal structure of a bacterial arylsulfate sulfotransferase catalytic intermediate with 4-methylumbelliferone bound in the active site

Experimental Data Snapshot

  • Resolution: 2.40 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.175 
  • R-Value Observed: 0.175 

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A structural and biochemical basis for PAPS-independent sulfuryl transfer by aryl sulfotransferase from uropathogenic Escherichia coli.

Malojcic, G.Owen, R.L.Grimshaw, J.P.Brozzo, M.S.Dreher-Teo, H.Glockshuber, R.

(2008) Proc Natl Acad Sci U S A 105: 19217-19222

  • DOI: https://doi.org/10.1073/pnas.0806997105
  • Primary Citation of Related Structures:  
    3ELQ, 3ETS, 3ETT

  • PubMed Abstract: 

    Sulfotransferases are a versatile class of enzymes involved in numerous physiological processes. In mammals, adenosine 3'-phosphate-5'-phosphosulfate (PAPS) is the universal sulfuryl donor, and PAPS-dependent sulfurylation of small molecules, including hormones, sugars, and antibiotics, is a critical step in hepatic detoxification and extracellular signaling. In contrast, little is known about sulfotransferases in bacteria, which make use of sulfurylated molecules as mediators of cell-cell interactions and host-pathogen interactions. Bacterial arylsulfate sulfotransferases (also termed aryl sulfotransferases), in contrast to PAPS-dependent sulfotransferases, transfer sulfuryl groups exclusively among phenolic compounds in a PAPS-independent manner. Here, we report the crystal structure of the virulence factor arylsulfate sulfotransferase (ASST) from the prototypic, pyelonephritogenic Escherichia coli strain CFT073 at 2.0-A resolution, and 2 catalytic intermediates, at 2.1-A and 2.4-A resolution, with substrates bound in the active site. ASST is one of the largest periplasmic enzymes and its 3D structure differs fundamentally from all other structurally characterized sulfotransferases. Each 63.8-kDa subunit of the ASST homodimer comprises a 6-bladed beta-propeller domain and a C-terminal beta-sandwich domain. The active sites of the dimer are situated at the center of the channel formed by each beta-propeller and are defined by the side chains of His-252, His-356, Arg-374, and His-436. We show that ASST follows a ping-pong bi-bi reaction mechanism, in which the catalytic residue His-436 undergoes transient sulfurylation, a previously unreported covalent protein modification. The data provide a framework for understanding PAPS-independent sulfotransfer and a basis for drug design targeting this bacterial virulence factor.

  • Organizational Affiliation

    Institute of Molecular Biology and Biophysics, ETH Zurich, CH-8093 Zurich, Switzerland. goran@mol.biol.ethz.ch

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Arylsulfate sulfotransferase
A, B
571Escherichia coli CFT073Mutation(s): 0 
Gene Names: ASTAEcF11_2091
Find proteins for Q8FDI4 (Escherichia coli O6:H1 (strain CFT073 / ATCC 700928 / UPEC))
Explore Q8FDI4 
Go to UniProtKB:  Q8FDI4
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ8FDI4
Sequence Annotations
  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
Query on HS8
A, B
Experimental Data & Validation

Experimental Data

  • Resolution: 2.40 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.175 
  • R-Value Observed: 0.175 
  • Space Group: P 32 1 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 181.83α = 90
b = 181.83β = 90
c = 100.66γ = 120
Software Package:
Software NamePurpose
RemDAqdata collection
XDSdata reduction
SCALAdata scaling

Structure Validation

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Ligand Structure Quality Assessment 

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-11-25
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2017-10-25
    Changes: Refinement description
  • Version 1.3: 2023-09-06
    Changes: Data collection, Database references, Derived calculations, Refinement description