Disease relevance of cheD

• The mechanism of chemo- and phototactic signal transduction in the Archaeon H.salinarium, therefore, is similar to the two-component signaling system known from chemotaxis in the eubacterium E.coli [1].
• On the basis of the well-known biochemical mechanisms of chemotaxis in Escherichia coli, kinetic modeling of the events leading from chemoreceptor activation by ligand binding to the motility response has been performed with great success [2].
• Bacillus subtilis chemotaxis: a deviation from the Escherichia coli paradigm [3].
• To illustrate this approach, we highlight three cases where our combined procedure has provided novel insights into our understanding of chemotaxis, possible prophage remnants in Halobacterium NRC-1 and archaeal transcriptional regulators [4].

High impact information on cheD

• Inspection of the halobacterial genome suggests that BasB and CosB exclusively mediate chemotaxis responses without any additional role in transport, which is in contrast to bacterial binding proteins, which are always part of ABC transport systems [5].
• Behavioral testing of deletion mutants indicates that halobacterial chemotaxis towards branched-chain amino acids as well as compatible osmolytes of the betaine family requires both a binding and a transducer protein [5].
• Chemotaxis and phototaxis require a CheA histidine kinase in the archaeon Halobacterium salinarium [6].
• Our results provide the first experimental evidence for the functional coupling between SRI and HtrI and corroborate the proposed model in which HtrI acts as the signal transducer of this archaeal seven-helix photoreceptor in a way analogous to the bacterial chemotaxis transducers [7].
• The data suggest direct involvement of methylation and demethylation in mechanisms of both chemotaxis and phototaxis and identify adaptation as the sensory process in which those reactions are likely to be involved [8].

Chemical compound and disease context of cheD

• The SR-1 system is of special interest because the transducer accepting the signal from SR-1 was recently identified as Htr-1, a homologue of the methyl-accepting chemotaxis proteins which have been characterized in Escherichia coli [9].

Biological context of cheD

• Therefire, the HtrXI transducer appears to have a complex role in chemotaxis signal transduction [10].

Anatomical context of cheD

• The deduced protein sequence of HtrII predicts a eubacterial chemotaxis transducer type with two hydrophobic membrane-spanning segments connecting sizable domains in the periplasm and cytoplasm [11].
• Sensory rhodopsin-I (SRI), a phototaxis receptor of archaebacteria, is a retinal-binding protein that exists in the cell membrane intimately associated with a signal-transducing protein (HtrI) homologous to eubacterial chemotaxis receptors [12].

Associations of cheD with chemical compounds

• Eubacterial transducers are transmembrane, methyl-accepting proteins central to chemotaxis systems and share common structural features [13].
• Our data identify BasT as the chemotaxis transducer protein for the branched chain amino acids leucine, isoleucine and valine as well as for methionine and cysteine [14].
• The taxis-negative and methyltransferase-deficient mutant, H. salinarium strain Pho72 did not exhibit changes in methanol release in response to aerotaxis or chemotaxis stimuli [15].

References