Crenactin from Pyrobaculum calidifontis is closely related to actin in structure and forms steep helical filaments

Thierry Izore, Ramona Duman, Danguole Kureisaite-Ciziene, Jan Lowe

Research output: Contribution to journalArticleResearchpeer-review

18 Citations (Scopus)


Polymerising proteins of the actin family are nearly ubiquitous. Crenactins, restricted to Crenarchaea, are more closely related to actin than bacterial MreB. Crenactins occur in gene clusters hinting at an unknown, but conserved function. We solved the crystal structure of crenactin at 3.2 Å resolution. The protein crystallises as a continuous right-handed helix with 8 subunits per complete turn, spanning 419 Å. The structure of crenactin shows several loops that are longer than in actin, but overall, crenactin is closely related to eukaryotic actin, with an RMSD of 1.6 Å. Crenactin filaments imaged by electron microscopy showed polymers with very similar helical parameters.
Original languageEnglish
Pages (from-to)776-782
Number of pages7
JournalFEBS Letters
Issue number5
Publication statusPublished - 3 Mar 2014
Externally publishedYes


  • Actin
  • Bacterial cytoskeleton
  • Crenarchaea
  • Cytomotive filament
  • Helical filament
  • MreB

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