Complex formation between recombinant ATP sulfurylase and APS reductase of Allium cepa (L.)

FEBS Lett. 2007 Sep 4;581(22):4139-47. doi: 10.1016/j.febslet.2007.07.062. Epub 2007 Aug 3.


Recombinant ATP sulfurylase (AcATPS1) and adenosine-5'-phosphosulfate reductase (AcAPR1) from Allium cepa have been used to determine if these enzymes form protein-protein complexes in vitro. Using a solid phase binding assay, AcAPR1 was shown to interact with AcATPS1. The AcAPR1 enzyme was also expressed in E. coli as the N-terminal reductase domain (AcAPR1-N) and the C-terminal glutaredoxin domain (AcAPR1-C), but neither of these truncated proteins interacted with AcATPS1. The solid-phase interactions were confirmed by immune-precipitation, where anti-AcATPS1 IgG precipitated the full-length AcAPR1 protein, but not AcAPR1-N and AcAPR1-C. Finally, using the ligand binding assay, full-length AcATPS1 has been shown to bind to membrane-localised full-length AcAPR1. The significance of an interaction between chloroplastidic ATPS and APR in A. cepa is evaluated with respect to the control of the reductive assimilation of sulfate.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Escherichia coli
  • Immunoassay
  • Immunoprecipitation
  • Ligands
  • Molecular Sequence Data
  • Onions / enzymology*
  • Oxidoreductases Acting on Sulfur Group Donors / chemistry
  • Oxidoreductases Acting on Sulfur Group Donors / metabolism*
  • Protein Binding
  • Recombinant Proteins / metabolism*
  • Substrate Specificity
  • Sulfate Adenylyltransferase / chemistry
  • Sulfate Adenylyltransferase / metabolism*


  • Ligands
  • Recombinant Proteins
  • Oxidoreductases Acting on Sulfur Group Donors
  • adenylylsulfate reductase
  • Sulfate Adenylyltransferase