NMR Studies on the Substrate-binding Domains of the Thermosome: Structural Plasticity in the Protrusion Region

Markus Heller, Michael John, Murray Coles, Gundula Bosch, Wolfgang Baumeister, Horst Kessler

Research output: Contribution to journalArticle

Abstract

Group II chaperonins close their cavity with the help of conserved, helical extensions, the so-called protrusions, which emanate from the apical or substrate-binding domains. A comparison of previously solved crystal structures of the apical domains of the thermosome from Thermoplasma acidophilum showed structural plasticity in the protrusion parts induced by extensive packing interactions. In order to assess the influence of the crystal contacts we investigated both the α and β-apical domains (α-ADT and β-ADT) in solution by NMR spectroscopy. Secondary structure assignments and 15N backbone relaxation measurements showed mostly rigid structural elements in the globular parts of the domains, but revealed intrinsic structural disorder and partial helix fraying in the protrusion regions. On the other hand, a β-turn-motif conserved in archaeal group II chaperonins might facilitate substrate recognition. Our results help us to specify the idea of the open, substrate-accepting state of the thermosome and may provide an additional jigsaw piece in understanding the mode of substrate binding of group II chaperonins.

Original languageEnglish (US)
Pages (from-to)717-729
Number of pages13
JournalJournal of molecular biology
Volume336
Issue number3
DOIs
StatePublished - Feb 20 2004
Externally publishedYes

Keywords

  • Apical domain
  • Chaperonin
  • Hydrogen exchange
  • Intrinsic disorder
  • Relaxation

ASJC Scopus subject areas

  • Structural Biology
  • Molecular Biology

Fingerprint Dive into the research topics of 'NMR Studies on the Substrate-binding Domains of the Thermosome: Structural Plasticity in the Protrusion Region'. Together they form a unique fingerprint.

  • Cite this