2KG6

Solution Structure of the acetyl Actinorhodin Acyl Carrier Protein from Streptomyces coelicolor


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Probing the Interactions of Early Polyketide Intermediates with the Actinorhodin ACP from S. coelicolor A3(2).

Evans, S.E.Williams, C.Arthur, C.J.Ploskon, E.Wattana-Amorn, P.Cox, R.J.Crosby, J.Willis, C.L.Simpson, T.J.Crump, M.P.

(2009) J.Mol.Biol. 389: 511-528

  • DOI: 10.1016/j.jmb.2009.03.072
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Acyl carrier proteins (ACPs) are essential to both fatty acid synthase (FAS) and polyketide synthase (PKS) biosynthetic pathways, yet relatively little is known about how they function at a molecular level. Seven thiol ester and thiol ether derivativ ...

    Acyl carrier proteins (ACPs) are essential to both fatty acid synthase (FAS) and polyketide synthase (PKS) biosynthetic pathways, yet relatively little is known about how they function at a molecular level. Seven thiol ester and thiol ether derivatives of the actinorhodin (act) PKS ACP from Streptomyces coelicolor have been prepared and structurally characterised by NMR to gain insight into ACP-intermediate interactions. Holo ACP synthase has been used to prepare early-stage ACP intermediates of polyketide biosynthesis (holo ACP, acetyl ACP, and malonyl ACP) from the respective coenzyme A derivatives. A synthetic route to stabilised thiol ether ACPs was developed and applied to the preparation of stable 3-oxobutyl and 3,5-dioxohexyl ACP as diketide and triketide analogues. No interaction between the protein and the acyl phosphopantetheine moieties of acetyl, malonyl, or 3-oxobutyl ACP was detected. Analysis of (1)H-(15)N heteronuclear single quantum coherence and nuclear Overhauser enhancement spectroscopy spectra for the triketide ACP revealed exchange between a major ('Tri', 85%) and a minor protein conformer in which the polyketide interacts with the protein ('Tri(*)', 15%). Act ACP was also derivatised with butyryl, hexanoyl, and octanoyl groups. The corresponding NMR spectra showed large chemical shift perturbations centred on helices II and III, indicative of acyl chain binding and significant structural rearrangement. Unexpectedly, butyryl act ACP showed almost identical backbone (1)H-(15)N chemical shifts to Tri(*), suggesting comparable structural changes that might provide insight into the structurally uncharacterised polyketide bound form. Furthermore, butyryl ACP itself underwent slow conformational exchange with a second minor conformer (But(*)) with almost identical backbone chemical shifts to octanoyl act ACP. High-resolution NMR structures of these acylated forms revealed that act ACP was able to undergo dramatic conformational changes that exceed those seen in FAS ACPs. When compared to E. coli FAS ACP, the substrate binding pocket of the act PKS ACP has three specific amino acid substitutions (Thr39/Leu45, Ala68/Leu74, and Leu42/Thr48) that alter the size, shape, and location of this cavity. These conformational changes may play a role in protein-protein recognition and assist the binding of bulky polyketide intermediates.


    Organizational Affiliation

    School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Actinorhodin polyketide synthase acyl carrier protein
A
86Streptomyces coelicolor (strain ATCC BAA-471 / A3(2) / M145)Mutation(s): 1 
Find proteins for Q02054 (Streptomyces coelicolor (strain ATCC BAA-471 / A3(2) / M145))
Go to UniProtKB:  Q02054
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SXA
Query on SXA

Download SDF File 
Download CCD File 
A
THIOACETIC ACID S-{2-[3-(2-HYDROXY-3,3-DIMETHYL-4-PHOSPHONOOXY-BUTYRYLAMINO)-PROPIONYLAMINO]-ETHYL} ESTER
C13 H25 N2 O8 P S
AJFWMDFTVVFMHY-LLVKDONJSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 2KG6 Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-04-14
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance