Reconstruction of the chemotaxis receptor–kinase assembly

  title={Reconstruction of the chemotaxis receptor–kinase assembly},
  author={Sang-Youn Park and Peter P. Borbat and Gabriela Gonzalez-Bonet and Jaya Bhatnagar and Abiola M. Pollard and Jack H. Freed and Alexandrine M. Bilwes and Brian R. Crane},
  journal={Nature Structural \&Molecular Biology},
In bacterial chemotaxis, an assembly of transmembrane receptors, the CheA histidine kinase and the adaptor protein CheW processes environmental stimuli to regulate motility. The structure of a Thermotoga maritima receptor cytoplasmic domain defines CheA interaction regions and metal ion–coordinating charge centers that undergo chemical modification to tune receptor response. Dimeric CheA–CheW, defined by crystallography and pulsed ESR, positions two CheWs to form a cleft that is lined with… 

Self-assembly of receptor/signaling complexes in bacterial chemotaxis

This work finds that analogous complexes self-assembled with a monomeric cytoplasmic domain fragment of the serine receptor without the leucine zipper dimerization domain, and have essentially the same size, composition, and architecture as those formed from lzTarC.

CheA-receptor interaction sites in bacterial chemotaxis.

CheA Kinase of bacterial chemotaxis: chemical mapping of four essential docking sites.

An enhanced version of the protein-interactions-by-cysteine-modification method (PICM-beta) is utilized to map out docking surfaces on CheA essential for kinase activity and for core complex assembly, suggesting that the same docking sites are widely utilized in prokaryotic sensory pathways.

Identification of a Kinase-Active CheA Conformation in Escherichia coli Chemoreceptor Signaling Complexes

Amino acid replacements at residues predicted to stablize the so-called "dipped" CheA.P4 conformation abolished the kinase activity of CheA and its ability to support chemotaxis.

Engineered chemotaxis core signaling units indicate a constrained kinase-off state

The model developed through extensive structural and biochemical analyses of reconstituted core units revealed that chemoreceptors maintained the inhibited state of the signaling core by preventing the domains of CheA that form the active kinase from interacting productively.

Defining a key receptor-CheA kinase contact and elucidating its function in the membrane-bound bacterial chemosensory array: a disulfide mapping and TAM-IDS Study.

The results reveal that the native array interface between the receptor protein interaction region and the kinase regulatory domain is accurately described, and suggests a simple model for the rearrangement of the interface triggered by the attractant signal and for longer range transmission of the signal in the chemosensory array.

Bacterial chemoreceptor arrays are hexagonally packed trimers of receptor dimers networked by rings of kinase and coupling proteins

This work has combined X-ray crystallography of purified proteins with electron cryotomography of native arrays inside cells to reveal the arrangement of the component transmembrane receptors, histidine kinases (CheA) and CheW coupling proteins.

Regulatory Role of an Interdomain Linker in the Bacterial Chemotaxis Histidine Kinase CheA

It is demonstrated that the interdomain linker is an active module that has the ability to impose regulatory effects on CheA activity and suggests that chemoreceptors may manipulate the conformation of the P4-P5 linker to achieve CheA regulation in the platform of the signaling complex.

Regulation of the chemotaxis histidine kinase CheA: A structural perspective.




Cysteine-Scanning Analysis of the Chemoreceptor-Coupling Domain of the Escherichia coli Chemotaxis Signaling Kinase CheA

All but four of the binding-defective P5-Cys proteins were defective in receptor-mediated activation, suggesting that CheW binding, as measured in vitro, is necessary for assembly of ternary signaling complexes and/or subsequent CheA activation.

Mechanism of CheA protein kinase activation in receptor signaling complexes.

The chemotaxis receptor for aspartate, Tar, generates responses by regulating the activity of an associated histidine kinase, CheA. Tar is composed of an extracellular sensory domain connected by a

Structural and Chemical Requirements for Histidine Phosphorylation by the Chemotaxis Kinase CheA*

High resolution crystallographic studies revealed that although all mutants disrupt the hydrogen-bonding network to varying degrees, none affect the conformation of His-45, and 15N-NMR chemical shift studies showed that Glu-67 functions to stabilize the unfavored Nδ1H tautomer of His, thereby rendering the Nϵ2 imidazole unprotonated and well positioned for accepting the ATP phosphoryl group.

Insights into the organization and dynamics of bacterial chemoreceptor clusters through in vivo crosslinking studies

It is proposed that clustered receptors are organized in mixed trimers of dimers through binding interactions with CheA and CheW, which play distinctly different architectural roles, and once complete signaling teams have formed, they no longer undergo dynamic exchange of receptor members.

Receptor‐mediated protein kinase activation and the mechanism of transmembrane signaling in bacterial chemotaxis

These findings suggest a mechanism for transmembrane signaling whereby stimulus‐induced changes in lateral packing interactions within an array of receptor‐sensing domains at the cell surface perturb an equilibrium between active and inactive receptor–kinase complexes within the cytoplasm.