2REE

Crystal structure of the loading GNATL domain of CurA from Lyngbya majuscula


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.211 
  • R-Value Work: 0.172 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

GNAT-like strategy for polyketide chain initiation.

Gu, L.Geders, T.W.Wang, B.Gerwick, W.H.Hakansson, K.Smith, J.L.Sherman, D.H.

(2007) Science 318: 970-974

  • DOI: 10.1126/science.1148790
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • An unexpected biochemical strategy for chain initiation is described for the loading module of the polyketide synthase of curacin A, an anticancer lead derived from the marine cyanobacterium Lyngbya majuscula. A central GCN5-related N-acetyltransfera ...

    An unexpected biochemical strategy for chain initiation is described for the loading module of the polyketide synthase of curacin A, an anticancer lead derived from the marine cyanobacterium Lyngbya majuscula. A central GCN5-related N-acetyltransferase (GNAT) domain bears bifunctional decarboxylase/S-acetyltransferase activity, both unprecedented for the GNAT superfamily. A CurA loading tridomain, consisting of an adaptor domain, the GNAT domain, and an acyl carrier protein, was assessed biochemically, revealing that a domain showing homology to GNAT (GNAT(L)) catalyzes (i) decarboxylation of malonyl-coenzyme A (malonyl-CoA) to acetyl-CoA and (ii) direct S-acetyl transfer from acetyl-CoA to load an adjacent acyl carrier protein domain (ACP(L)). Moreover, the N-terminal adapter domain was shown to facilitate acetyl-group transfer. Crystal structures of GNAT(L) were solved at 1.95 angstroms (ligand-free form) and 2.75 angstroms (acyl-CoA complex), showing distinct substrate tunnels for acyl-CoA and holo-ACP(L) binding. Modeling and site-directed mutagenesis experiments demonstrated that histidine-389 and threonine-355, at the convergence of the CoA and ACP tunnels, participate in malonyl-CoA decarboxylation but not in acetyl-group transfer. Decarboxylation precedes acetyl-group transfer, leading to acetyl-ACP(L) as the key curacin A starter unit.


    Organizational Affiliation

    Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CurA
A, B
224Lyngbya majusculaMutation(s): 0 
Gene Names: curA
Find proteins for Q6DNF2 (Lyngbya majuscula)
Go to UniProtKB:  Q6DNF2
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

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Download CCD File 
A, B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
CL
Query on CL

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Download CCD File 
A
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
GOL
Query on GOL

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Download CCD File 
A, B
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.211 
  • R-Value Work: 0.172 
  • Space Group: P 31 2 1
Unit Cell:
Length (Å)Angle (°)
a = 91.463α = 90.00
b = 91.463β = 90.00
c = 138.877γ = 120.00
Software Package:
Software NamePurpose
Blu-Icedata collection
DENZOdata reduction
REFMACrefinement
RESOLVEphasing
SOLVEphasing
PDB_EXTRACTdata extraction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-11-20
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Source and taxonomy, Version format compliance
  • Version 1.2: 2017-10-25
    Type: Refinement description