Skip to main content

Investigation of the role of electrostatic charge in activation of the Escherichia coli response regulator CheY.

Publication ,  Journal Article
Smith, JG; Latiolais, JA; Guanga, GP; Citineni, S; Silversmith, RE; Bourret, RB
Published in: J Bacteriol
November 2003

In a two-component regulatory system, an important means of signal transduction in microorganisms, a sensor kinase phosphorylates a response regulator protein on an aspartyl residue, resulting in activation. The active site of the response regulator is highly charged (containing a lysine, the phosphorylatable aspartate, two additional aspartates involved in metal binding, and an Mg(2+) ion), and introduction of the dianionic phosphoryl group results in the repositioning of charged moieties. Furthermore, substitution of one of the Mg(2+)-coordinating aspartates with lysine or arginine in the Escherichia coli chemotaxis response regulator CheY results in phosphorylation-independent activation. In order to examine the consequences of altered charge distribution for response regulator activity and to identify possible additional amino acid substitutions that result in phosphorylation-independent activation, we made 61 CheY mutants in which residues close to the site of phosphorylation (Asp57) were replaced by various charged amino acids. Most substitutions (47 of 61) resulted in the complete loss of CheY activity, as measured by the inability to support clockwise flagellar rotation. However, 10 substitutions, all introducing a new positive charge, resulted in the loss of chemotaxis but in the retention of some clockwise flagellar rotation. Of the mutants in this set, only the previously identified CheY13DK and CheY13DR mutants displayed clockwise activity in the absence of the CheA sensor kinase. The absence of negatively charged substitution mutants with residual activity suggests that the introduction of additional negative charges into the active site is particularly deleterious for CheY function. Finally, the spatial distribution of positions at which amino acid substitutions are functionally tolerated or not tolerated is consistent with the presently accepted mechanism of response regulator activation and further suggests a possible role for Met17 in signal transduction by CheY.

Duke Scholars

Published In

J Bacteriol

DOI

ISSN

0021-9193

Publication Date

November 2003

Volume

185

Issue

21

Start / End Page

6385 / 6391

Location

United States

Related Subject Headings

  • Static Electricity
  • Signal Transduction
  • Protein Structure, Tertiary
  • Mutation
  • Microbiology
  • Methyl-Accepting Chemotaxis Proteins
  • Membrane Proteins
  • Magnesium
  • Histidine Kinase
  • Flagella
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Smith, J. G., Latiolais, J. A., Guanga, G. P., Citineni, S., Silversmith, R. E., & Bourret, R. B. (2003). Investigation of the role of electrostatic charge in activation of the Escherichia coli response regulator CheY. J Bacteriol, 185(21), 6385–6391. https://doi.org/10.1128/JB.185.21.6385-6391.2003
Smith, Jenny G., Jamie A. Latiolais, Gerald P. Guanga, Sindhura Citineni, Ruth E. Silversmith, and Robert B. Bourret. “Investigation of the role of electrostatic charge in activation of the Escherichia coli response regulator CheY.J Bacteriol 185, no. 21 (November 2003): 6385–91. https://doi.org/10.1128/JB.185.21.6385-6391.2003.
Smith JG, Latiolais JA, Guanga GP, Citineni S, Silversmith RE, Bourret RB. Investigation of the role of electrostatic charge in activation of the Escherichia coli response regulator CheY. J Bacteriol. 2003 Nov;185(21):6385–91.
Smith, Jenny G., et al. “Investigation of the role of electrostatic charge in activation of the Escherichia coli response regulator CheY.J Bacteriol, vol. 185, no. 21, Nov. 2003, pp. 6385–91. Pubmed, doi:10.1128/JB.185.21.6385-6391.2003.
Smith JG, Latiolais JA, Guanga GP, Citineni S, Silversmith RE, Bourret RB. Investigation of the role of electrostatic charge in activation of the Escherichia coli response regulator CheY. J Bacteriol. 2003 Nov;185(21):6385–6391.

Published In

J Bacteriol

DOI

ISSN

0021-9193

Publication Date

November 2003

Volume

185

Issue

21

Start / End Page

6385 / 6391

Location

United States

Related Subject Headings

  • Static Electricity
  • Signal Transduction
  • Protein Structure, Tertiary
  • Mutation
  • Microbiology
  • Methyl-Accepting Chemotaxis Proteins
  • Membrane Proteins
  • Magnesium
  • Histidine Kinase
  • Flagella