Search results for "Histidine Kinase"
showing 10 items of 28 documents
The NMR structure of the sensory domain of the membranous two-component fumarate sensor (histidine protein kinase) DcuS of Escherichia coli
2003
The structure of the water-soluble, periplasmic domain of the fumarate sensor DcuS (DcuS-pd) has been determined by NMR spectroscopy in solution. DcuS is a prototype for a sensory histidine kinase with transmembrane signal transfer. DcuS belongs to the CitA family of sensors that are specific for sensing di- and tricarboxylates. The periplasmic domain is folded autonomously and shows helices at the N and the C terminus, suggesting direct linking or connection to helices in the two transmembrane regions. The structure constitutes a novel fold. The nearest structural neighbor is the Per-Arnt-Sim domain of the photoactive yellow protein that binds small molecules covalently. Residues Arg107, H…
Function of DcuS from Escherichia coli as a Fumarate-stimulated Histidine Protein Kinase in Vitro
2002
The two-component regulatory system DcuSR of Escherichia coli controls the expression of genes of C(4)-dicarboxylate metabolism in response to extracellular C(4)- dicarboxylates such as fumarate or succinate. DcuS is a membrane-integral sensor kinase, and the sensory and kinase domains are located on opposite sides of the cytoplasmic membrane. The intact DcuS protein (His(6)-DcuS) was overproduced and isolated in detergent containing buffer. His(6)-DcuS was reconstituted into liposomes made from E. coli phospholipids. Reconstituted His(6)-DcuS catalyzed, in contrast to the detergent-solubilized sensor, autophosphorylation by [gamma-(33)P]ATP with an approximate K(D) of 0.16 mm for ATP. Up t…
Comparative analysis of two paradigm bacteriophytochromes reveals opposite functionalities in two-component signaling
2021
Bacterial phytochrome photoreceptors usually belong to two-component signaling systems which transmit environmental stimuli to a response regulator through a histidine kinase domain. Phytochromes switch between red light-absorbing and far-red light-absorbing states. Despite exhibiting extensive structural responses during this transition, the model bacteriophytochrome from Deinococcus radiodurans (DrBphP) lacks detectable kinase activity. Here, we resolve this long-standing conundrum by comparatively analyzing the interactions and output activities of DrBphP and a bacteriophytochrome from Agrobacterium fabrum (Agp1). Whereas Agp1 acts as a conventional histidine kinase, we identify DrBphP a…
Tips and turns of bacteriophytochrome photoactivation
2020
Phytochromes are ubiquitous photosensor proteins, which control the growth, reproduction and movement in plants, fungi and bacteria. Phytochromes switch between two photophysical states depending on the light conditions. In analogy to molecular machines, light absorption induces a series of structural changes that are transduced from the bilin chromophore, through the protein, and to the output domains. Recent progress towards understanding this structural mechanism of signal transduction has been manifold. We describe this progress with a focus on bacteriophytochromes. We describe the mechanism along three structural tiers, which are the chromophore-binding pocket, the photosensory module,…
Evolutionary history of the OmpR/IIIA family of signal transduction two component systems in Lactobacillaceae and Leuconostocaceae
2011
15 pages, 3 tables, 7 figures.
Histidine kinases mediate differentiation, stress response, and pathogenicity in Magnaporthe oryzae.
2014
The aim of this study is a functional characterization of 10 putative histidine kinases (HIKs)-encoding genes in the phytopathogenic fungus Magnaporthe oryzae. Two HIKs were found to be required for pathogenicity in the fungus. It was found that the mutant strains ΔMohik5 and ΔMohik8 show abnormal conidial morphology and furthermore ΔMohik5 is unable to form appressoria. Both HIKs MoHik5p and MoHik8p appear to be essential for pathogenicity since the mutants fail to infect rice plants. MoSln1p and MoHik1p were previously reported to be components of the HOG pathway in M. oryzae. The ΔMosln1 mutant is more susceptible to salt stress compared to ΔMohik1, whereas ΔMohik1 appears to be stronger…
Requirement of the Lactobacillus casei MaeKR two-component system for L-malic acid utilization via a malic enzyme pathway.
2009
ABSTRACTLactobacillus caseican metabolizel-malic acid via malolactic enzyme (malolactic fermentation [MLF]) or malic enzyme (ME). Whereas utilization ofl-malic acid via MLF does not support growth, the ME pathway enablesL. caseito grow onl-malic acid. In this work, we have identified in the genomes ofL. caseistrains BL23 and ATCC 334 a cluster consisting of two diverging operons,maePEandmaeKR, encoding a putative malate transporter (maeP), an ME (maeE), and a two-component (TC) system belonging to the citrate family (maeKandmaeR). Homologous clusters were identified inEnterococcus faecalis,Streptococcus agalactiae,Streptococcus pyogenes, andStreptococcus uberis. Our results show that ME is …
Structural photoactivation of a full-length bacterial phytochrome
2016
Time-resolved x-ray solution scattering reveals the conformational signaling mechanism of a bacterial phytochrome.
Oligomeric Sensor Kinase DcuS in the Membrane of Escherichia coli and in Proteoliposomes: Chemical Cross-linking and FRET Spectroscopy
2010
The DcuSR (dicarboxylate uptake sensor and regulator) system of Escherichia coli is a typical two-component system consisting of a membranous sensor kinase (DcuS) and a cytoplasmic response regulator (DcuR) (11, 26, 48). DcuS responds to C4-dicarboxylates like fumarate, malate, or succinate (19). In the presence of the C4-dicarboxlates, the expression of the genes of anaerobic fumarate respiration (dcuB, fumB, and frdABCD) and of aerobic C4-dicarboxylate uptake (dctA) is activated. DcuS is a histidine protein kinase composed of two transmembrane helices with an intermittent sensory PAS domain in the periplasm (PASP) that was also termed the PDC domain (for PhoQ/DcuS/DctB/CitA domain or fold…
Fumarate regulation of gene expression in Escherichia coli by the DcuSR (dcuSR genes) two-component regulatory system.
1998
ABSTRACT In Escherichia coli the genes encoding the anaerobic fumarate respiratory system are transcriptionally regulated by C 4 -dicarboxylates. The regulation is effected by a two-component regulatory system, DcuSR, consisting of a sensory histidine kinase (DcuS) and a response regulator (DcuR). DcuS and DcuR are encoded by the dcuSR genes (previously yjdHG ) at 93.7 min on the calculated E. coli map. Inactivation of the dcuR and dcuS genes caused the loss of C 4 -dicarboxylate-stimulated synthesis of fumarate reductase ( frdABCD genes) and of the anaerobic fumarate-succinate antiporter DcuB ( dcuB gene). DcuS is predicted to contain a large periplasmic domain as the supposed site for C 4…