PDBsum entry 1e0r

Chaperonin

PDB id: 1e0r

Contents

Protein chain

154 a.a. *

* Residue conservation analysis

PDB id:

1e0r

Name:

Chaperonin

Title:

Beta-apical domain of thermosome

Structure:

Thermosome. Chain: b. Fragment: substrate-binding domain. Synonym: beta-apical domain. Engineered: yes. Mutation: yes. Other_details: lys 364 is followed by asn 365 and hexahistidine tail

Source:

Thermoplasma acidophilum. Organism_taxid: 2303. Atcc: 25905. Cellular_location: cytoplasm. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Biol. unit:

Dimer (from PDB file)

Resolution:

2.80Å R-factor: 0.261 R-free: 0.318

Authors:

G.Bosch,W.Baumeister,L.-O.Essen

Key ref:

G.Bosch et al. (2000). Crystal structure of the beta-apical domain of the thermosome reveals structural plasticity in the protrusion region. J Mol Biol, 301, 19-25. PubMed id: 10926489 DOI: 10.1006/jmbi.2000.3955

Date:

06-Apr-00 Release date: 19-Aug-00

Protein chain

P48425  (THSB_THEAC) -  Thermosome subunit beta from Thermoplasma acidophilum (strain ATCC 25905 / DSM 1728 / JCM 9062 / NBRC 15155 / AMRC-C165)

Seq: 543 a.a.

Struc: 154 a.a.*

* PDB and UniProt seqs differ at 3 residue positions (black crosses)

DOI no: 10.1006/jmbi.2000.3955

J Mol Biol 301:19-25 (2000)

PubMed id: 10926489

Crystal structure of the beta-apical domain of the thermosome reveals structural plasticity in the protrusion region.

G.Bosch, W.Baumeister, L.O.Essen.

ABSTRACT

The crystal structure of the beta-apical domain of the thermosome, an archaeal group II chaperonin from Thermoplasma acidophilum, has been determined at 2.8 A resolution. The structure shows an invariant globular core from which a 25 A long protrusion emanates, composed of an elongated alpha-helix (H10) and a long extended stretch consisting of residues GluB245-ThrB253. A comparison with previous apical domain structures reveals a large segmental displacement of the protruding part of helix H10 via the hinge GluB276-ValB278. The region comprising residues GluB245-ThrB253 adopts an extended beta-like conformation rather than the alpha-helix seen in the alpha-apical domain. Consequently, it appears that the protrusions of the apical domains from group II chaperonins might assume a variety of context-dependent conformations during an open, substrate-accepting state of the chaperonin. Sequence variations in the protrusion regions that are found in the eukaryotic TRiC/CCT subunits may provide different structural propensities and hence serve different roles in substrate recognition.

Selected figure(s)

Figure 2.
Figure 2. Stereo view of the isolated b-apical domain structure (violet) superimposed on the two crystal forms A and B of the isolated a-apical domain (yellow and orange) and the structures of the a and b-apical domains in the intact thermosome (blue and green). The globular core is shown in grey for all structures.

Figure 3.
Figure 3. Influence of the structural context on the secondary structure of the protrusions. (a) and (b) Interactions between neighbouring domains in the crystal lattice in the crystals of the isolated a and b-apical domain. (c) Top view of the fully closed thermosome showing the circularly closed b-sheet (generated from PDB entry 1A6D).

The above figures are reprinted by permission from Elsevier: J Mol Biol (2000, 301, 19-25) copyright 2000.

Figures were selected by an automated process.