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Gene Review

ECs2598  -  chemotaxis protein CheA

Escherichia coli O157:H7 str. Sakai

 
 
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Disease relevance of ECs2598

  • Dimers were engineered of the cytoplasmic domain of the Escherichia coli aspartate receptor that stimulated the kinase CheA in vitro [1].
  • The chemoreceptors of enteric bacteria mediate attractant responses by interrupting a phosphotransfer circuit initiated at receptor complexes with the protein kinase CheA [2].
  • Comparison of the functionally interchangeable CheA proteins of E. coli and Salmonella typhimurium revealed two extensively mismatched segments within the phosphotransfer region, 22 and 25 aa long, with sequences characteristic of domain linkers [3].
  • FrzE of Myxococcus xanthus is homologous to both CheA and CheY of Salmonella typhimurium [4].
  • The structure of Thermotoga maritima CheA domain P2 in complex with CheY reveals a different association than that observed for the same Escherichia coli proteins [5].
 

Psychiatry related information on ECs2598

  • Delta cheZ excitation response times increased with stimulus size consistent with formation of an occluded CheA state [6].
 

High impact information on ECs2598

  • We showed previously that phosphorylation of CheY is activated in reactions containing receptor, CheW, CheA, and CheY [7].
  • A quaternary complex formed which consisted of the response regulator CheY, the histidine protein kinase CheA, a coupling protein CheW and a membrane-bound chemoreceptor Tar. Using various experimental conditions and mutant proteins, we have shown that the complex dissociates under conditions that favour phosphorylation of CheY [8].
  • In chemotaxis, the CheA kinase passes a phosphoryl group to the cytoplasmic protein CheY, which functions as a phosphorylation-activated switch that interacts with flagellar components to regulate motility [9].
  • The folding free energy of the leucine-zipper dimerization domain was harnessed to twist the dimer interface of the receptor, which markedly affected the extent of CheA activation [1].
  • Fusing the cytoplasmic domain of the aspartate receptor, Tar, to a leucine zipper dimerization domain produces a hybrid, lzTar(C), that forms soluble complexes with CheA and CheW [10].
 

Chemical compound and disease context of ECs2598

 

Biological context of ECs2598

  • Mutant CheA proteins were tested in vitro for phosphorylation and were grouped into four classes: nonphosphorylated, partially phosphorylated, phosphorylated but not dephosphorylated by CheB and CheY, and phosphorylated and dephosphorylated [15].
  • The active site of CheY is exposed by the binding of the kinase domain, possibly to enhance phosphotransfer from CheA to CheY [16].
  • To test the effects of differential methylation on receptor function, we prepared membranes from cells that have specifically modified forms of the receptor and tested the relative ability of each of these forms to activate or inhibit CheA kinase [17].
  • It is difficult to study this interaction in vivo, because the dynamics of phosphorylation of CheY by its kinase CheA and the hydrolysis of CheY (accelerated by CheZ) are not under direct experimental control [18].
  • These studies have provided a wealth of detailed molecular structures, including the structures of CheA, CheW, and the cytoplasmic domain of the serine receptor Tsr [19].
 

Anatomical context of ECs2598

 

Associations of ECs2598 with chemical compounds

  • The aspartate receptor (Tar) is a homodimer, and oligomerized cytoplasmic domains stimulate CheA activity much more than monomers do in vitro [2].
  • Studies on mutant strains showed that the receptor proteins (methyl-accepting chemotaxis proteins, MCPs) were not required for the Ca(2+)-induced tumbling but that CheA, CheW, and CheY proteins were required [23].
  • The alanine and tryptophan mutants evidently assemble defective receptor complexes that cannot modulate CheA activity in response to serine stimuli [24].
  • A single amino-acid substitution within this binding region on CheY, alanine to valine at position 103, significantly decreases the affinity of CheY for CheA [25].
  • Finally, a novel approach termed "protein interactions by cysteine modification" indicates that the exposed C-terminal face of helix alpha7 provides an essential docking site for the kinase CheA or for the coupling protein CheW [11].
 

Analytical, diagnostic and therapeutic context of ECs2598

  • CheW was found to exist as monomers and CheA was found to exist as dimers by equilibrium analytical ultracentrifugation [26].
  • To understand the structural basis for these activities, we examined the domain organization of the CheA phosphotransfer region by using DNA sequence analysis, limited proteolytic digestion, and a genetic technique called domain liberation [3].
  • Subunit organization in a soluble complex of tar, CheW, and CheA by electron microscopy [27].
  • We used an enzyme-linked immunosorbent assay to study the direct interaction between the kinase, CheA, and the regulator, CheY [28].
  • The carboxy-terminal portion of CheA was previously shown to be dispensable for autophosphorylation, but required for regulation in response to environmental signals transmitted through a transducer and CheW [29].

References

  1. Imitation of Escherichia coli aspartate receptor signaling in engineered dimers of the cytoplasmic domain. Cochran, A.G., Kim, P.S. Science (1996) [Pubmed]
  2. Attractant signaling by an aspartate chemoreceptor dimer with a single cytoplasmic domain. Gardina, P.J., Manson, M.D. Science (1996) [Pubmed]
  3. Liberation of an interaction domain from the phosphotransfer region of CheA, a signaling kinase of Escherichia coli. Morrison, T.B., Parkinson, J.S. Proc. Natl. Acad. Sci. U.S.A. (1994) [Pubmed]
  4. FrzE of Myxococcus xanthus is homologous to both CheA and CheY of Salmonella typhimurium. McCleary, W.R., Zusman, D.R. Proc. Natl. Acad. Sci. U.S.A. (1990) [Pubmed]
  5. In different organisms, the mode of interaction between two signaling proteins is not necessarily conserved. Park, S.Y., Beel, B.D., Simon, M.I., Bilwes, A.M., Crane, B.R. Proc. Natl. Acad. Sci. U.S.A. (2004) [Pubmed]
  6. Determinants of chemotactic signal amplification in Escherichia coli. Kim, C., Jackson, M., Lux, R., Khan, S. J. Mol. Biol. (2001) [Pubmed]
  7. The dynamics of protein phosphorylation in bacterial chemotaxis. Borkovich, K.A., Simon, M.I. Cell (1990) [Pubmed]
  8. Assembly and function of a quaternary signal transduction complex monitored by surface plasmon resonance. Schuster, S.C., Swanson, R.V., Alex, L.A., Bourret, R.B., Simon, M.I. Nature (1993) [Pubmed]
  9. Three-dimensional structure of CheY, the response regulator of bacterial chemotaxis. Stock, A.M., Mottonen, J.M., Stock, J.B., Schutt, C.E. Nature (1989) [Pubmed]
  10. Self-assembly of receptor/signaling complexes in bacterial chemotaxis. Wolanin, P.M., Baker, M.D., Francis, N.R., Thomas, D.R., Derosier, D.J., Stock, J.B. Proc. Natl. Acad. Sci. U.S.A. (2006) [Pubmed]
  11. Detection of a conserved alpha-helix in the kinase-docking region of the aspartate receptor by cysteine and disulfide scanning. Bass, R.B., Falke, J.J. J. Biol. Chem. (1998) [Pubmed]
  12. Elucidation of a PTS-carbohydrate chemotactic signal pathway in Escherichia coli using a time-resolved behavioral assay. Lux, R., Munasinghe, V.R., Castellano, F., Lengeler, J.W., Corrie, J.E., Khan, S. Mol. Biol. Cell (1999) [Pubmed]
  13. Neither motility nor chemotaxis plays a role in the ability of Escherichia coli F-18 to colonize the streptomycin-treated mouse large intestine. McCormick, B.A., Laux, D.C., Cohen, P.S. Infect. Immun. (1990) [Pubmed]
  14. Cysteine-scanning analysis of the chemoreceptor-coupling domain of the Escherichia coli chemotaxis signaling kinase CheA. Zhao, J., Parkinson, J.S. J. Bacteriol. (2006) [Pubmed]
  15. Mutants defective in bacterial chemotaxis show modified protein phosphorylation. Oosawa, K., Hess, J.F., Simon, M.I. Cell (1988) [Pubmed]
  16. Two binding modes reveal flexibility in kinase/response regulator interactions in the bacterial chemotaxis pathway. McEvoy, M.M., Hausrath, A.C., Randolph, G.B., Remington, S.J., Dahlquist, F.W. Proc. Natl. Acad. Sci. U.S.A. (1998) [Pubmed]
  17. Attenuation of sensory receptor signaling by covalent modification. Borkovich, K.A., Alex, L.A., Simon, M.I. Proc. Natl. Acad. Sci. U.S.A. (1992) [Pubmed]
  18. Control of direction of flagellar rotation in bacterial chemotaxis. Scharf, B.E., Fahrner, K.A., Turner, L., Berg, H.C. Proc. Natl. Acad. Sci. U.S.A. (1998) [Pubmed]
  19. Three-dimensional structure and organization of a receptor/signaling complex. Francis, N.R., Wolanin, P.M., Stock, J.B., Derosier, D.J., Thomas, D.R. Proc. Natl. Acad. Sci. U.S.A. (2004) [Pubmed]
  20. Stimulus response coupling in bacterial chemotaxis: receptor dimers in signalling arrays. Levit, M.N., Liu, Y., Stock, J.B. Mol. Microbiol. (1998) [Pubmed]
  21. Helicobacter pylori possesses two CheY response regulators and a histidine kinase sensor, CheA, which are essential for chemotaxis and colonization of the gastric mucosa. Foynes, S., Dorrell, N., Ward, S.J., Stabler, R.A., McColm, A.A., Rycroft, A.N., Wren, B.W. Infect. Immun. (2000) [Pubmed]
  22. Both CheA and CheW are required for reconstitution of chemotactic signaling in Escherichia coli. Conley, M.P., Wolfe, A.J., Blair, D.F., Berg, H.C. J. Bacteriol. (1989) [Pubmed]
  23. Calcium ions are involved in Escherichia coli chemotaxis. Tisa, L.S., Adler, J. Proc. Natl. Acad. Sci. U.S.A. (1992) [Pubmed]
  24. Collaborative signaling by mixed chemoreceptor teams in Escherichia coli. Ames, P., Studdert, C.A., Reiser, R.H., Parkinson, J.S. Proc. Natl. Acad. Sci. U.S.A. (2002) [Pubmed]
  25. Localized perturbations in CheY structure monitored by NMR identify a CheA binding interface. Swanson, R.V., Lowry, D.F., Matsumura, P., McEvoy, M.M., Simon, M.I., Dahlquist, F.W. Nat. Struct. Biol. (1995) [Pubmed]
  26. Signal transduction in bacteria: CheW forms a reversible complex with the protein kinase CheA. Gegner, J.A., Dahlquist, F.W. Proc. Natl. Acad. Sci. U.S.A. (1991) [Pubmed]
  27. Subunit organization in a soluble complex of tar, CheW, and CheA by electron microscopy. Francis, N.R., Levit, M.N., Shaikh, T.R., Melanson, L.A., Stock, J.B., DeRosier, D.J. J. Biol. Chem. (2002) [Pubmed]
  28. Mutations leading to altered CheA binding cluster on a face of CheY. Shukla, D., Matsumura, P. J. Biol. Chem. (1995) [Pubmed]
  29. Intermolecular complementation of the kinase activity of CheA. Swanson, R.V., Bourret, R.B., Simon, M.I. Mol. Microbiol. (1993) [Pubmed]
 
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