4JYM

crystal Structure of KAI2 in complex with 3-methyl-2H-furo[2,3-c]pyran-2-one


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.35 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.182 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Smoke-derived karrikin perception by the alpha/beta-hydrolase KAI2 from Arabidopsis.

Guo, Y.Zheng, Z.La Clair, J.J.Chory, J.Noel, J.P.

(2013) Proc.Natl.Acad.Sci.USA 110: 8284-8289

  • DOI: 10.1073/pnas.1306265110
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Genetic studies in Arabidopsis implicate an α/β-hydrolase, KARRIKIN-INSENSITIVE 2 (KAI2) as a receptor for karrikins, germination-promoting butenolide small molecules found in the smoke of burned plants. However, direct biochemical evidence for the i ...

    Genetic studies in Arabidopsis implicate an α/β-hydrolase, KARRIKIN-INSENSITIVE 2 (KAI2) as a receptor for karrikins, germination-promoting butenolide small molecules found in the smoke of burned plants. However, direct biochemical evidence for the interaction between KAI2 and karrikin and for the mechanism of downstream signaling by a KAI2-karrikin complex remain elusive. We report crystallographic analyses and ligand-binding experiments for KAI2 recognition of karrikins. The karrikin-1 (KAR1) ligand sits in the opening to the active site abutting a helical domain insert but distal from the canonical catalytic triad (Ser95-His246-Asp217) of α/β-hydrolases, consistent with the lack of detectable hydrolytic activity by purified KAI2. The closest approach of KAR1 to Ser95-His246-Asp217 is 3.8 Å from His246. Six aromatic side chains, including His246, encapsulate KAR1 through geometrically defined aromatic-aromatic interactions. KAR1 binding induces a conformational change in KAI2 at the active site entrance. A crevice of hydrophobic residues linking the polar edge of KAR1 and the helical domain insert suggests that KAI2-KAR1 creates a contiguous interface for binding signaling partners in a ligand-dependent manner.


    Organizational Affiliation

    Jack H. Skirball Center for Chemical Biology and Proteomics, Salk Institute for Biological Studies, La Jolla, CA 92037, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Hydrolase, alpha/beta fold family protein
A, B
270Arabidopsis thalianaMutation(s): 0 
Gene Names: KAI2 (D14L, HTL)
Find proteins for Q9SZU7 (Arabidopsis thaliana)
Go to UniProtKB:  Q9SZU7
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
KKN
Query on KKN

Download SDF File 
Download CCD File 
A, B
3-methyl-2H-furo[2,3-c]pyran-2-one
C8 H6 O3
JUTMAMXOAOYKHT-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
KKNKd: 9050 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.35 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.182 
  • Space Group: P 1
Unit Cell:
Length (Å)Angle (°)
a = 50.950α = 90.04
b = 53.200β = 90.04
c = 55.760γ = 116.03
Software Package:
Software NamePurpose
PHENIXrefinement
PHASERphasing
MOSFLMdata reduction
SCALAdata scaling
PDB_EXTRACTdata extraction
BOSdata collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-05-08
    Type: Initial release
  • Version 1.1: 2013-06-19
    Type: Database references