PDBsum entry 2asr

Chemotaxis

PDB id: 2asr

Contents

Protein chain

142 a.a. *

Ligands

SO4 ×2

Waters ×108

* Residue conservation analysis

PDB id:

2asr

Name:

Chemotaxis

Title:

The three-dimensional structure of the aspartate receptor from escherichia coli

Structure:

Aspartate receptor. Chain: a. Engineered: yes

Source:

Escherichia coli. Organism_taxid: 562

Biol. unit:

Dimer (from PQS)

Resolution:

2.30Å R-factor: 0.203

Authors:

J.U.Bowie,A.A.Pakula,M.I.Simon

Key ref:

J.U.Bowie et al. (1995). The three-dimensional structure of the aspartate receptor from Escherichia coli. Acta Crystallogr D Biol Crystallogr, 51, 145-154. PubMed id: 15299315 DOI: 10.1107/S0907444994010498

Date:

23-Aug-94 Release date: 01-Nov-94

Protein chain

P07017  (MCP2_ECOLI) -  Methyl-accepting chemotaxis protein II from Escherichia coli (strain K12)

Seq: 553 a.a.

Struc: 142 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1107/S0907444994010498

Acta Crystallogr D Biol Crystallogr 51:145-154 (1995)

PubMed id: 15299315

The three-dimensional structure of the aspartate receptor from Escherichia coli.

J.U.Bowie, A.A.Pakula, M.I.Simon.

ABSTRACT

The crystal structure of the periplasmic domain of the aspartate receptor from Escherichia coli has been solved and refined to an R-factor of 0.203 at 2.3 A, resolution. The dimeric protein is largely helical, with four helices from each monomer forming a four-helix bundle. The dimer interface is constructed from four helices, two from each subunit, also packed together in a four-helix bundle arrangement. A sulfate ion occupies the aspartate-binding site. All hydrogen bonds made to aspartate are substituted by direct or water-mediated hydrogen bonds to the sulfate. Comparison of the Escherichia coli aspartate-receptor structure with that of Salmonella typhimurium [Milburn, Prive, Milligan, Scott, Yeh, Jancarik, Koshland & Kim (1991). Science, 254, 1342-1347; Scott, Milligan, Milburn, Prive, Yeh, Koshland & Kim (1993). J. Mol. Biol. 232, 555-573] reveals strong conservation in the structure of the monomer, but more divergence in the orientation of the subunits with respect to one another. Mutations that render the Escherichia coli receptor incapable of responding to maltose are either located in spatially conserved sites or in regions of the structures that have high temperature factors and are therefore likely to be quite flexible. The inability of the receptor from Salmonella typhimurium to respond to maltose may, therefore, be because of differences in amino acids located on the binding surface rather than structural differences.

Selected figure(s)

Figure 4.
Fig. 4. The AR-Ec dimer structure. (a) A ribbon drawing showing the sulfate bound in the aspartate-binding pocket in a ball-and-stick representation. (b) A stereoview of the Ca trace. The figure was produced using the program MOLSCRIPT (Kraulis, 1991).

Figure 7.
Fig. 7. Location of mal- mutations. The structure of AR-Ec (light grey) is shown superimposed on the structure of AR-St-apo (dark grey). Position of the mal- mutations are indicated on the AR-Ec structure by black balls at their Ca positions. The figure was produced using the program MOLSCRIPT (Kraulis, 1991)

The above figures are reprinted by permission from the IUCr: Acta Crystallogr D Biol Crystallogr (1995, 51, 145-154) copyright 1995.

Figures were selected by an automated process.