PDBsum entry: 1crz

Toxin binding protein

PDB id: 1crz

Contents

Protein chain

403 a.a. *

Waters ×458

* Residue conservation analysis

PDB id:

1crz

Name:

Toxin binding protein

Title:

Crystal structure of the e. Coli tolb protein

Structure:

Tolb protein. Chain: a. Engineered: yes

Source:

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

Resolution:

1.95Å R-factor: 0.238 R-free: 0.238

Authors:

C.Abergel,E.Bouveret,J-M.Claverie,K.Brown,A.Rigal, C.Lazdunski,H.Benedetti

Key ref:

C.Abergel et al. (1999). Structure of the Escherichia coli TolB protein determined by MAD methods at 1.95 A resolution. Structure, 7, 1291-1300. PubMed id: 10545334 DOI: 10.1016/S0969-2126(00)80062-3

Date:

16-Aug-99 Release date: 16-Aug-00

Protein chain

P0A855  (TOLB_ECOLI) -  Protein tolB

Seq: 430 a.a.

Struc: 403 a.a.

 Gene Ontology (GO) functional annotation 

• Cellular component: membrane (3 terms)
• Biological process: transport (5 terms)
• Biochemical function: protein binding (1 term)

DOI no: 10.1016/S0969-2126(00)80062-3

Structure 7:1291-1300 (1999)

PubMed id: 10545334

Structure of the Escherichia coli TolB protein determined by MAD methods at 1.95 A resolution.

C.Abergel, E.Bouveret, J.M.Claverie, K.Brown, A.Rigal, C.Lazdunski, H.Bénédetti.

ABSTRACT

BACKGROUND: The periplasmic protein TolB from Escherichia coli is part of the Tol-PAL (peptidoglycan-associated lipoprotein) multiprotein complex used by group A colicins to penetrate and kill cells. TolB homologues are found in many gram-negative bacteria and the Tol-PAL system is thought to play a role in bacterial envelope integrity. TolB is required for lethal infection by Salmonella typhimurium in mice. RESULTS: The crystal structure of the selenomethionine-substituted TolB protein from E. coli was solved using multiwavelength anomalous dispersion methods and refined to 1. 95 A. TolB has a two-domain structure. The N-terminal domain consists of two alpha helices, a five-stranded beta-sheet floor and a long loop at the back of this floor. The C-terminal domain is a six-bladed beta propeller. The small, possibly mobile, contact area (430 A(2)) between the two domains involves residues from the two helices and the first and sixth blades of the beta propeller. All available genomic sequences were used to identify new TolB homologues in gram-negative bacteria. The TolB structure was then interpreted using the observed conservation pattern. CONCLUSIONS: The TolB beta-propeller C-terminal domain exhibits sequence similarities to numerous members of the prolyl oligopeptidase family and, to a lesser extent, to class B metallo-beta-lactamases. The alpha/beta N-terminal domain shares a structural similarity with the C-terminal domain of transfer RNA ligases. We suggest that the TolB protein might be part of a multiprotein complex involved in the recycling of peptidoglycan or in its covalent linking with lipoproteins.

Selected figure(s)

Figure 3.
Figure 3. Molecular surfaces of the TolB protein structure. (a) Surface representation of the TolB structure colour-coded according to the surface property: dark blue corresponds to positively charged surfaces, red to negatively charged surfaces and yellow to hydrophobic surfaces. The figure was generated with the program GRASP [29]. (b) Solvent-accessible surface coloured according to electrostatic potential using GRASP defaults. The electrostatic potential is contoured in the range from -10k[B]T(red) to +10k[B]T (blue). The figure is rotated by 180° relative to (a).

The above figure is reprinted by permission from Cell Press: Structure (1999, 7, 1291-1300) copyright 1999.

Figure was selected by the author.