Locations of Mapped Genes:
|Superclasses:||Signal transduction pathways|
E. coli movement is typically described as a random three-dimensional walk in which runs of movement in a straight line are punctuated by tumbles as the cell briefly stops and randomly reorients before moving off again. This swimming/tumbling behaviour results from alternating clockwise (tumbling behavior) and counterclockwise (straight swimming behavior) flagellar rotation. Chemotaxis is the ability of E. coli to move or 'swim' towards or away from specific chemical attractants and repellents and is achieved by regulating the probability of CW and CCW flagella rotation via a modified two-component signal transduction pathway - the chemotactic signal transduction pathway. Pathway components include the dual function histidine kinase CheA, the response regulators CheY and CheB, plus CheW, CheR, and the transmembrane receptor proteins.
CheA is a dual function cytoplasmic histidine kinase which, in conjunction with one of the transmembrane receptor proteins (the so-called methyl accepting chemotaxis proteins - Tsr, Tar, Trg or Tap) and a linker protein CheW, forms a ternery signalling complex (MCPI, MCPII, MCPIII or MCPIV). Ligands interact with the receptor proteins and affect the flow of phosphoryl groups from CheA to two response regulators - CheY and CheB - neither of these proteins are transcription factors unlike the majority of two-component response regulators in E. coli. CheY influences flagella rotation by direct binding to the FliM protein - a component of the flagella motor switch complex. CheY and phosphoCheY bind to FliM with different affinities and influence the direction of flagellar rotation. CheB is a methylesterase which, along with CheR methyltransferase takes part in a feedback loop that enables the pathway to adapt to background stimuli.
Falke97: Falke JJ, Bass RB, Butler SL, Chervitz SA, Danielson MA (1997). "The two-component signaling pathway of bacterial chemotaxis: a molecular view of signal transduction by receptors, kinases, and adaptation enzymes." Annu Rev Cell Dev Biol 13;457-512. PMID: 9442881
Gegner92: Gegner JA, Graham DR, Roth AF, Dahlquist FW (1992). "Assembly of an MCP receptor, CheW, and kinase CheA complex in the bacterial chemotaxis signal transduction pathway." Cell 70(6);975-82. PMID: 1326408
Barak04a: Barak R, Prasad K, Shainskaya A, Wolfe AJ, Eisenbach M (2004). "Acetylation of the chemotaxis response regulator CheY by acetyl-CoA synthetase purified from Escherichia coli." J Mol Biol 342(2);383-401. PMID: 15327942
Barak92: Barak R, Welch M, Yanovsky A, Oosawa K, Eisenbach M (1992). "Acetyladenylate or its derivative acetylates the chemotaxis protein CheY in vitro and increases its activity at the flagellar switch." Biochemistry 31(41);10099-107. PMID: 1390767
Bhatnagar12: Bhatnagar J, Sircar R, Borbat PP, Freed JH, Crane BR (2012). "Self-association of the histidine kinase CheA as studied by pulsed dipolar ESR spectroscopy." Biophys J 102(9);2192-201. PMID: 22824284
Borkovich89: Borkovich KA, Kaplan N, Hess JF, Simon MI (1989). "Transmembrane signal transduction in bacterial chemotaxis involves ligand-dependent activation of phosphate group transfer." Proc Natl Acad Sci U S A 86(4);1208-12. PMID: 2645576
Bourret93: Bourret RB, Davagnino J, Simon MI (1993). "The carboxy-terminal portion of the CheA kinase mediates regulation of autophosphorylation by transducer and CheW." J Bacteriol 175(7);2097-101. PMID: 8384620
Briegel13: Briegel A, Ames P, Gumbart JC, Oikonomou CM, Parkinson JS, Jensen GJ (2013). "The mobility of two kinase domains in the Escherichia coli chemoreceptor array varies with signalling state." Mol Microbiol 89(5);831-41. PMID: 23802570
DiazMejia09: Diaz-Mejia JJ, Babu M, Emili A (2009). "Computational and experimental approaches to chart the Escherichia coli cell-envelope-associated proteome and interactome." FEMS Microbiol Rev 33(1);66-97. PMID: 19054114
Filimonov93: Filimonov VV, Prieto J, Martinez JC, Bruix M, Mateo PL, Serrano L (1993). "Thermodynamic analysis of the chemotactic protein from Escherichia coli, CheY." Biochemistry 1993;32(47);12906-21. PMID: 8251514
Francis04: Francis NR, Wolanin PM, Stock JB, Derosier DJ, Thomas DR (2004). "Three-dimensional structure and organization of a receptor/signaling complex." Proc Natl Acad Sci U S A 101(50);17480-5. PMID: 15572451
Garzon96: Garzon A, Parkinson JS (1996). "Chemotactic signaling by the P1 phosphorylation domain liberated from the CheA histidine kinase of Escherichia coli." J Bacteriol 178(23);6752-8. PMID: 8955292
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