Crystal structures of fusion proteins with large-affinity tags

Douglas R. Smyth, Marek K. Mrozkiewicz, William J. McGrath, Pawel Listwan, Bostjan Kobe

Research output: Contribution to journalReview articlepeer-review

186 Citations (Scopus)


The fusion of a protein of interest to a large-affinity tag, such as the maltose-binding protein (MBP), thioredoxin (TRX), or glutathione-S-transferase (GST), can be advantageous in terms of increased expression, enhanced solubility, protection from proteolysis, improved folding, and protein purification via affinity chromatography. Unfortunately, crystal growth is hindered by the conformational heterogeneity induced by the fusion tag, requiring that the tag is removed by a potentially problematic cleavage step. The first three crystal structures of fusion proteins with large-affinity tags have been reported recently. All three structures used a novel strategy to rigidly fuse the protein of interest to MBP via a short three- to five-amino acid spacer. This strategy has the potential to aid structure determination of proteins that present particular experimental challenges and are not conducive to more conventional crystallization strategies (e.g., membrane proteins). Structural genomics initiatives may also benefit from this approach as a way to crystallize problematic proteins of significant interest.

Original languageEnglish
Pages (from-to)1313-1322
Number of pages10
JournalProtein Science
Issue number7
Publication statusPublished - 1 Jul 2003
Externally publishedYes


  • Chimera
  • Fusion protein
  • Membrane proteins
  • Molecular replacement
  • Protein crystallization
  • Protein expression
  • Structural genomics
  • X-ray crystallography

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology

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