PDBsum entry 3jz3

Transferase

PDB id: 3jz3

Contents

Protein chains

151 a.a. *

159 a.a. *

Ligands

SO4

Waters ×44

* Residue conservation analysis

PDB id:

3jz3

Name:

Transferase

Title:

Structure of the cytoplasmic segment of histidine kinase qsec

Structure:

Sensor protein qsec. Chain: a, b. Fragment: unp residues 236-449. Engineered: yes

Source:

Escherichia coli. Organism_taxid: 83333. Strain: k12. Gene: qsec, ygiy, b3026, jw2994. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.50Å R-factor: 0.230 R-free: 0.262

Authors:

W.Xie,W.Kwiatkowski,S.Choe,Center For Structures Of Membrane Proteins (Csmp)

Key ref:

W.Xie et al. (2010). Structure of the cytoplasmic segment of histidine kinase receptor QseC, a key player in bacterial virulence. Protein Pept Lett, 17, 1383-1391. PubMed id: 20594156

Date:

22-Sep-09 Release date: 21-Jul-10

Protein chain

P40719  (QSEC_ECOLI) -  Sensor protein QseC from Escherichia coli (strain K12)

Seq: 449 a.a.

Struc: 151 a.a.

Protein chain

P40719  (QSEC_ECOLI) -  Sensor protein QseC from Escherichia coli (strain K12)

Seq: 449 a.a.

Struc: 159 a.a.

Enzyme reactions

• Enzyme class: Chains A, B: E.C.2.7.13.3 - histidine kinase.
• Reaction: ATP + protein L-histidine = ADP + protein N-phospho-L-histidine

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

reference

Protein Pept Lett 17:1383-1391 (2010)

PubMed id: 20594156

Structure of the cytoplasmic segment of histidine kinase receptor QseC, a key player in bacterial virulence.

W.Xie, C.Dickson, W.Kwiatkowski, S.Choe.

ABSTRACT

QseC is a histidine kinase (HK) receptor involved in quorum sensing, a mechanism by which bacteria respond to fluctuations in cell population. We conducted a structural study of the cytoplasmic domain of QseC (QseC-CD) using X-ray crystallography. The 2.5 A structure of the apo-enzyme revealed that the kinase domain of QseC retains the overall fold of the typical HK kinase domain. The construct that we used is inactive in the autokinase reaction and its inactivity is most likely caused by its atypical dimerization interface, as compared to that observed in the T.maritima HK cytoplasmic domain structure. Restoration of the activity may require that the entire dimerization domain be present in the protein construct. QseC, which plays an important role in bacterial pathogenesis, is a promising drug target and the structure of QseC-CD provides a platform for developing more potent inhibitors of pathogen virulence.