Essential role of proline isomerization in stefin B tetramer formation

J Mol Biol. 2007 Mar 9;366(5):1569-79. doi: 10.1016/j.jmb.2006.12.025. Epub 2006 Dec 16.

Abstract

Here we present the tetrameric structure of stefin B, which is the result of a process by which two domain-swapped dimers of stefin B are transformed into tetramers. The transformation involves a previously unidentified process of extensive intermolecular contacts, termed hand shaking, which occurs concurrently with trans to cis isomerization of proline 74. This proline residue is widely conserved throughout the cystatin superfamily, a member of which, human cystatin C, is the key protein in cerebral amyloid angiopathy. These results are consistent with the hypothesis that isomerization of proline residues can play a decisive role in amyloidogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Amino Acid Substitution
  • Amyloid / chemistry
  • Amyloid / metabolism
  • Amyloid / ultrastructure
  • Circular Dichroism
  • Cross-Linking Reagents
  • Crystallography, X-Ray
  • Cystatin B
  • Cystatins / chemistry*
  • Cystatins / genetics
  • Cystatins / metabolism*
  • Dimerization
  • Genetic Variation
  • Glutaral / chemistry
  • Humans
  • Hydrogen-Ion Concentration
  • Isomerism
  • Light
  • Models, Chemical
  • Models, Molecular
  • Molecular Sequence Data
  • Nuclear Magnetic Resonance, Biomolecular
  • Proline / chemistry
  • Proline / metabolism*
  • Protein Conformation
  • Protein Folding
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Scattering, Radiation
  • Sequence Homology, Amino Acid
  • Serine / metabolism
  • Solutions / chemistry
  • Trifluoroethanol / pharmacology

Substances

  • Amyloid
  • CSTB protein, human
  • Cross-Linking Reagents
  • Cystatins
  • Solutions
  • Serine
  • Trifluoroethanol
  • Cystatin B
  • Proline
  • Glutaral

Associated data

  • PDB/2OCT