PDBsum entry: 1b3q

Transferase

PDB-id: 1b3q

Biological unit* = asymmetric unit,
as shown
(*as deduced by PQS)

Contents

Description

Header details

Header records

References

PROCHECK

Protein chains

368 a.a. *

Metal ions

_HG ×2

Waters ×187

* Residue conservation analysis

Tools

Clefts Calculation

PDB id:

1b3q

Name:

Transferase

Title:

Crystal structure of chea-289, a signal transducing histidine kinase

Structure:

Protein (chemotaxis protein chea). Chain: a, b. Fragment: dimerization domain, kinase domain and regulatory domain. Engineered: yes. Mutation: yes

Source:

Thermotoga maritima. Organism_taxid: 2336. Cellular_location: cytoplasm. Expressed in: escherichia coli bl21. Expression_system_taxid: 511693.

Biological unit:

Dimer (from PQS)

UniProt:

Chains A, B: Q56310 (CHEA_THEMA)

Seq:

Struc:

Seq:

Struc:

Seq:

671 a.a.

Struc:

368 a.a.*

Key:	PfamA domain
Secondary structure	CATH domain

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

Enzyme class:

E.C.2.7.13.3   [IntEnz]   [ExPASy]   [KEGG]   [BRENDA]

Reaction:

ATP + protein L-histidine = ADP + protein N-phospho-L-histidine

Resolution:

2.60Å

R-factor:

0.213

R-free:

0.285

Authors:

A.M.Bilwes,L.A.Alex,B.R.Crane,M.I.Simon

Key ref:

A.M.Bilwes et al. (1999). Structure of CheA, a signal-transducing histidine kinase.. Cell, 96, 131-141. [PubMed id: 9989504] [DOI: 10.1016/S0092-8674(00)80966-6]

Date:

14-Dec-98

Release date:

15-Dec-99

Quick_links

Procheck

Clefts

Surface

Key reference

DOI no: 10.1016/S0092-8674(00)80966-6

Cell 96:131-141 (1999)

PubMed id: 9989504

Structure of CheA, a signal-transducing histidine kinase.

A.M.Bilwes, L.A.Alex, B.R.Crane, M.I.Simon.

ABSTRACT

Histidine kinases allow bacteria, plants, and fungi to sense and respond to their environment. The 2.6 A resolution crystal structure of Thermotoga maritima CheA (290-671) histidine kinase reveals a dimer where the functions of dimerization, ATP binding, and regulation are segregated into domains. The kinase domain is unlike Ser/Thr/Tyr kinases but resembles two ATPases, Gyrase B and Hsp90. Structural analogies within this superfamily suggest that the P1 domain of CheA provides the nucleophilic histidine and activating glutamate for phosphotransfer. The regulatory domain, which binds the homologous receptor-coupling protein CheW, topologically resembles two SH3 domains and provides different protein recognition surfaces at each end. The dimerization domain forms a central four-helix bundle about which the kinase and regulatory domains pivot on conserved hinges to modulate transphosphorylation. Different subunit conformations suggest that relative domain motions link receptor response to kinase activity.

Selected figure(s)

Figure 1.
Figure 1. Two Classes of Histidine KinasesGeneralized schematic diagram dividing histidine kinases into two classes based on the position in the sequence of the substrate histidine (H box) with respect to the kinase domain. H, N, G1, F, and G2 boxes are conserved sequence motifs among histidine kinases ([1]). Arrows represent the flow of phosphate through these systems. CheW is the coupling protein that interacts (hashed lines) with the sensor (receptor) and CheA.

Figure 8.
Figure 8. Mobility about Hinges Indicated by Different Subunit ConformationsThe two subunits that form the dimer (dark colors for MOL1, light for MOL2) in the asymmetric unit are not superimposable. The positioning of MOL1 onto MOL2 was generated after least-square superposition of the C α from the dimerization domain only. Different positioning of each domain with respect to its neighbors in the asymmetric unit results from rotation around the conserved hinges (yellow) at residues 354 and 540. As a result, interfaces between domains differ in the two subunits. In the more closed conformation (light, MOL2)α 10 from the regulatory domain interacts with the kinase domain near the proposed position of the γ-phosphate (center), possibly interfering with the association of the CheA domain P1.

The above figures are reprinted by permission from Cell Press: Cell (1999, 96, 131-141) copyright 1999.

Figures were selected by an automated process.