PDBsum entry: 1q6u

Isomerase

PDB id: 1q6u

Contents

Protein chain

213 a.a. *

Metals

_CS

Waters ×116

* Residue conservation analysis

PDB id:

1q6u

Name:

Isomerase

Title:

Crystal structure of fkpa from escherichia coli

Structure:

Fkbp-type peptidyl-prolyl cis-trans isomerase fkp chain: a. Synonym: ppiase, rotamase. Engineered: yes

Source:

Escherichia coli. Organism_taxid: 562. Gene: fkpa or b3347. Expressed in: escherichia coli. Expression_system_taxid: 562.

Biol. unit:

Dimer (from PDB file)

Resolution:

2.45Å R-factor: 0.214 R-free: 0.277

Authors:

F.A.Saul,J.-P.Arie,B.Vulliez-Le Normand,R.Kahn,J.-M.Betton, G.A.Bentley

Key ref:

F.A.Saul et al. (2004). Structural and functional studies of FkpA from Escherichia coli, a cis/trans peptidyl-prolyl isomerase with chaperone activity. J Mol Biol, 335, 595-608. PubMed id: 14672666 DOI: 10.1016/j.jmb.2003.10.056

Date:

14-Aug-03 Release date: 13-Jan-04

Protein chain

P45523  (FKBA_ECOLI) -  FKBP-type peptidyl-prolyl cis-trans isomerase fkpA

Seq: 270 a.a.

Struc: 213 a.a.

Enzyme reactions

• Enzyme class: E.C.5.2.1.8 - Peptidylprolyl isomerase.
• Reaction: Peptidylproline (omega=180) = peptidylproline (omega=0)

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

 Gene Ontology (GO) functional annotation 

• Cellular component: periplasmic space (1 term)
• Biological process: protein folding (2 terms)
• Biochemical function: isomerase activity (2 terms)

Added reference

DOI no: 10.1016/j.jmb.2003.10.056

J Mol Biol 335:595-608 (2004)

PubMed id: 14672666

Structural and functional studies of FkpA from Escherichia coli, a cis/trans peptidyl-prolyl isomerase with chaperone activity.

F.A.Saul, J.P.Arié, B.Vulliez-le Normand, R.Kahn, J.M.Betton, G.A.Bentley.

ABSTRACT

The protein FkpA from the periplasm of Escherichia coli exhibits both cis/trans peptidyl-prolyl isomerase (PPIase) and chaperone activities. The crystal structure of the protein has been determined in three different forms: as the full-length native molecule, as a truncated form lacking the last 21 residues, and as the same truncated form in complex with the immunosuppressant ligand, FK506. FkpA is a dimeric molecule in which the 245-residue subunit is divided into two domains. The N-terminal domain includes three helices that are interlaced with those of the other subunit to provide all inter-subunit contacts maintaining the dimeric species. The C-terminal domain, which belongs to the FK506-binding protein (FKBP) family, binds the FK506 ligand. The overall form of the dimer is V-shaped, and the different crystal structures reveal a flexibility in the relative orientation of the two C-terminal domains located at the extremities of the V. The deletion mutant FkpNL, comprising the N-terminal domain only, exists in solution as a mixture of monomeric and dimeric species, and exhibits chaperone activity. By contrast, a deletion mutant comprising the C-terminal domain only is monomeric, and although it shows PPIase activity, it is devoid of chaperone function. These results suggest that the chaperone and catalytic activities reside in the N and C-terminal domains, respectively. Accordingly, the observed mobility of the C-terminal domains of the dimeric molecule could effectively adapt these two independent folding functions of FkpA to polypeptide substrates.

Selected figure(s)

Figure 1.
Figure 1. Stereo view of the complex formed between FkpA-DCT dimer and the immunosuppressant FK506. Two orthogonal views are shown: (a) perpendicular to, and (b) along, the non-crystallographic 2-fold axis. The structure is shown schematically in ribbon and loop representation. The b strands, present in the C-terminal domains are shown in yellow. Helical regions are coloured green and blue for the respective monomers. The bound FK506 molecules are shown in red.

Figure 3.
Figure 3. Comparison of the C-domain of FkpA-DCT, shown in red, with HuFKBP12, shown in blue, after superposition of equivalent C^a coordinates. The comparison is shown as a stereo view of the C^a skeletons.

The above figures are reprinted by permission from Elsevier: J Mol Biol (2004, 335, 595-608) copyright 2004.

Figures were selected by an automated process.