PDBsum entry 2c7e

Cell cycle

PDB id: 2c7e

Contents

Protein chains

(+ 8 more) 525 a.a. *

Ligands

ATP ×7

Metals

__K ×7

_MG ×7

Waters ×42

* Residue conservation analysis

PDB id:

2c7e

Name:

Cell cycle

Title:

Revised atomic structure fitting into a groel(d398a)-atp7 cryo-em map (emd 1047)

Structure:

60 kda chaperonin. Chain: a, b, c, d, e, f, g, h, i, j, k, l, m, n. Synonym: groel, protein cpn60, groel protein. Engineered: yes. Mutation: yes

Source:

Escherichia coli. Organism_taxid: 562. Expressed in: escherichia coli. Expression_system_taxid: 562

Biol. unit:

40mer (from PQS)

Authors:

N.A.Ranson,G.W.Farr,A.M.Roseman,B.Gowen,W.A.Fenton,A.L.Horwich, H.R.Saibil

Key ref:

N.A.Ranson et al. (2001). ATP-bound states of GroEL captured by cryo-electron microscopy. Cell, 107, 869-879. PubMed id: 11779463 DOI: 10.1016/S0092-8674(01)00617-1

Date:

22-Nov-05 Release date: 16-Feb-06

Supersedes:

1gr6

Protein chains

P0A6F5  (CH60_ECOLI) -  Chaperonin GroEL from Escherichia coli (strain K12)

Seq: 548 a.a.

Struc: 525 a.a.*

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.5.6.1.7 - chaperonin ATPase.
• Reaction: ATP + H2O + a folded polypeptide = ADP + phosphate + an unfolded polypeptide

ATP (Bound ligand (Het Group name = ATP) corresponds exactly) + H2O + folded polypeptide = ADP + phosphate + unfolded polypeptide

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

reference

DOI no: 10.1016/S0092-8674(01)00617-1

Cell 107:869-879 (2001)

PubMed id: 11779463

ATP-bound states of GroEL captured by cryo-electron microscopy.

N.A.Ranson, G.W.Farr, A.M.Roseman, B.Gowen, W.A.Fenton, A.L.Horwich, H.R.Saibil.

ABSTRACT

The chaperonin GroEL drives its protein-folding cycle by cooperatively binding ATP to one of its two rings, priming that ring to become folding-active upon GroES binding, while simultaneously discharging the previous folding chamber from the opposite ring. The GroEL-ATP structure, determined by cryo-EM and atomic structure fitting, shows that the intermediate domains rotate downward, switching their intersubunit salt bridge contacts from substrate binding to ATP binding domains. These observations, together with the effects of ATP binding to a GroEL-GroES-ADP complex, suggest structural models for the ATP-induced reduction in affinity for polypeptide and for cooperativity. The model for cooperativity, based on switching of intersubunit salt bridge interactions around the GroEL ring, may provide general insight into cooperativity in other ring complexes and molecular machines.

Selected figure(s)

Figure 5.
Figure 5. Intersubunit Contacts(a) A closeup view of the intermediate domain orientation in the unliganded T ring of GroEL-ATP.(b) A similar view of the intermediate domain orientation in the ATP-bound R ring. The equatorial (green), intermediate (yellow), and apical (red) domains of parts of two adjacent subunits are shown inside a blue/yellow wire mesh surface representing the EM density. The change in color of the mesh indicates the boundary between the two subunits in each view. The T ring contains density at the E386-R197 salt bridge. In the R ring, E386 makes a new contact near K80 and D83 in the neighboring equatorial domain.

Figure 7.
Figure 7. Domain Twisting Caused by ATP Binding to the Open Ring of GroEL-GroES-ADPCryo-EM structure to 12.5 Å resolution of the GroES-ADP[7]-GroEL-ATP[7] complex isolated from a reaction mixture. The cryo-EM map is shown as a blue transparent surface, with the atomic structure docked in. The GroEL domains are colored as in Figure 2, and GroES is cyan. The precision of the fit is demonstrated by the side view (a). The white circle in (a) indicates the position of the R197-E386 contact. The free apical domains (lower ring in [a]) are docked into the end view (b) with a counterclockwise rotation of 20° ± 5°. The white dotted lines are orientation markers for comparison of the apical rotation here with that in Figure 3a.

The above figures are reprinted by permission from Cell Press: Cell (2001, 107, 869-879) copyright 2001.

Figures were selected by an automated process.