Hypothetical protein AF2241 from Archaeoglobus fulgidus adopts a cyclophilin-like fold

J Biomol NMR. 2007 Aug;38(4):353-8. doi: 10.1007/s10858-007-9172-8. Epub 2007 Jul 4.

Abstract

AF2241 is a hypothetical protein from Archaeoglobus fulgidus and it belongs to the PFam domain of unknown function 369 (DUF369). NMR structural determination reveals that AF2241 adopts a cyclophilin-like fold, with a beta-barrel core composed of eight beta-strands, one alpha-helix, and one 3(10) helix located at each end of the barrel. The protein displays a high structural similarity to TM1367, another member of DUF369 whose structure has been determined recently by X-ray crystallography. Structural similarity search shows that AF2241 also has a high similarity to human cyclophilin A, however, sequence alignment and electrostatic potential analysis reveal that the residues in the PPIase catalytic site of human cyclophilin A are not conserved in AF2241 or TM1367. Instead, a putative active site of AF2241 maps to a negatively charged pocket composed of 9 conserved residues. Our results suggest that although AF2241 adopts the same fold as the human cyclophilin A, it may have distinct biological function.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Archaeal Proteins / chemistry*
  • Archaeoglobus fulgidus / metabolism*
  • Binding Sites
  • Crystallography, X-Ray
  • Cyclophilin A / chemistry*
  • Humans
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Molecular Sequence Data
  • Nuclear Magnetic Resonance, Biomolecular / methods*
  • Protein Conformation
  • Protein Structure, Secondary
  • Proteomics / methods
  • Sequence Homology, Amino Acid
  • Static Electricity

Substances

  • Archaeal Proteins
  • Cyclophilin A