4KYQ

Structure of a product bound plant phosphatase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.64 Å
  • R-Value Free: 0.199 
  • R-Value Work: 0.157 
  • R-Value Observed: 0.159 

Starting Model: experimental
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wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structure of the Arabidopsis Glucan Phosphatase LIKE SEX FOUR2 Reveals a Unique Mechanism for Starch Dephosphorylation.

Meekins, D.A.Guo, H.F.Husodo, S.Paasch, B.C.Bridges, T.M.Santelia, D.Kotting, O.Vander Kooi, C.W.Gentry, M.S.

(2013) Plant Cell 25: 2302-2314

  • DOI: https://doi.org/10.1105/tpc.113.112706
  • Primary Citation of Related Structures:  
    4KYQ, 4KYR

  • PubMed Abstract: 

    Starch is a water-insoluble, Glc-based biopolymer that is used for energy storage and is synthesized and degraded in a diurnal manner in plant leaves. Reversible phosphorylation is the only known natural starch modification and is required for starch degradation in planta. Critical to starch energy release is the activity of glucan phosphatases; however, the structural basis of dephosphorylation by glucan phosphatases is unknown. Here, we describe the structure of the Arabidopsis thaliana starch glucan phosphatase like sex four2 (LSF2) both with and without phospho-glucan product bound at 2.3Å and 1.65Å, respectively. LSF2 binds maltohexaose-phosphate using an aromatic channel within an extended phosphatase active site and positions maltohexaose in a C3-specific orientation, which we show is critical for the specific glucan phosphatase activity of LSF2 toward native Arabidopsis starch. However, unlike other starch binding enzymes, LSF2 does not possess a carbohydrate binding module domain. Instead we identify two additional glucan binding sites located within the core LSF2 phosphatase domain. This structure is the first of a glucan-bound glucan phosphatase and provides new insights into the molecular basis of this agriculturally and industrially relevant enzyme family as well as the unique mechanism of LSF2 catalysis, substrate specificity, and interaction with starch granules.


  • Organizational Affiliation

    Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, Kentucky 40535-0509, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Phosphoglucan phosphatase LSF2, chloroplastic208Arabidopsis thalianaMutation(s): 0 
Gene Names: At3g10940AT3G10940.1F9F8.24LSF2
EC: 3.1.3
UniProt
Find proteins for Q9SRK5 (Arabidopsis thaliana)
Explore Q9SRK5 
Go to UniProtKB:  Q9SRK5
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ9SRK5
Sequence Annotations
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
FLC
Query on FLC

Download Ideal Coordinates CCD File 
B [auth A]CITRATE ANION
C6 H5 O7
KRKNYBCHXYNGOX-UHFFFAOYSA-K
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.64 Å
  • R-Value Free: 0.199 
  • R-Value Work: 0.157 
  • R-Value Observed: 0.159 
  • Space Group: P 21 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 51.82α = 90
b = 99.582β = 90
c = 37.763γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
PHASERphasing
REFMACrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2013-07-24
    Type: Initial release
  • Version 1.1: 2013-08-14
    Changes: Database references
  • Version 1.2: 2017-11-15
    Changes: Refinement description
  • Version 1.3: 2023-09-20
    Changes: Data collection, Database references, Derived calculations, Refinement description