Crystal structures of OrfX2 and P47 from a Botulinum neurotoxin OrfX-type gene cluster

Research output: Contribution to journalArticle


Botulinum neurotoxins are highly toxic substances and are all encoded together with one of two alternative gene clusters, the HA or the OrfX gene cluster. Very little is known about the function and structure of the proteins encoded in the OrfX gene cluster, which in addition to the toxin contains five proteins (OrfX1, OrfX2, OrfX3, P47, and NTNH). We here present the structures of OrfX2 and P47, solved to 2.1 and 1.8 Å, respectively. We show that they belong to the TULIP protein superfamily, which are often involved in lipid binding. OrfX1 and OrfX2 were both found to bind phosphatidylinositol lipids.


  • Robert Gustafsson
  • Ronnie P-A Berntsson
  • Markel Martínez-Carranza
  • Geniver El Tekle
  • Richard Odegrip
  • Eric A Johnson
  • Pål Stenmark
External organisations
  • Stockholm University
Research areas and keywords


  • Bacterial Proteins/chemistry, Cloning, Molecular, Clostridium botulinum/chemistry, Crystallography, X-Ray, Models, Molecular, Multigene Family, Phosphatidylinositols/metabolism, Protein Binding, Protein Conformation
Original languageEnglish
Pages (from-to)3781-3792
JournalFEBS Letters
Issue number22
Publication statusPublished - 2017 Nov
Publication categoryResearch
Externally publishedYes

Bibliographic note

© 2017 Federation of European Biochemical Societies.