TY - JOUR
T1 - Organization of the receptor-kinase signaling array that regulates Escherichia coli chemotaxis
AU - Levit, Mikhail N.
AU - Grebe, Thorsten W.
AU - Stock, Jeffry B.
PY - 2002/9/27
Y1 - 2002/9/27
N2 - Motor behavior in prokaryotes is regulated by a phosphorelay network involving a histidine protein kinase, CheA, whose activity is controlled by a family of Type I membrane receptors. In a typical Escherichia coli cell, several thousand receptors are organized together with CheA and an Src homology 3-like protein, CheW, into complexes that tend to be localized at the cell poles. We found that these complexes have at least 6 receptors per CheA. CheW is not required for CheA binding to receptors, but is essential for kinase activation. The kinase activity per mole of bound CheA is proportional to the total bound CheW. Similar results were obtained with the E. coli serine receptor, Tsr, and the Salmonella typhimurium aspartate receptor, Tar. In the case of Tsr, under conditions optimal for kinase activation, the ratio of subunits in complexes is ∼6 Tsr:4 CheW:1 CheA. Our results indicate that information from numerous receptors is integrated to control the activity of a relatively small number of kinase molecules.
AB - Motor behavior in prokaryotes is regulated by a phosphorelay network involving a histidine protein kinase, CheA, whose activity is controlled by a family of Type I membrane receptors. In a typical Escherichia coli cell, several thousand receptors are organized together with CheA and an Src homology 3-like protein, CheW, into complexes that tend to be localized at the cell poles. We found that these complexes have at least 6 receptors per CheA. CheW is not required for CheA binding to receptors, but is essential for kinase activation. The kinase activity per mole of bound CheA is proportional to the total bound CheW. Similar results were obtained with the E. coli serine receptor, Tsr, and the Salmonella typhimurium aspartate receptor, Tar. In the case of Tsr, under conditions optimal for kinase activation, the ratio of subunits in complexes is ∼6 Tsr:4 CheW:1 CheA. Our results indicate that information from numerous receptors is integrated to control the activity of a relatively small number of kinase molecules.
UR - http://www.scopus.com/inward/record.url?scp=0037184003&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0037184003&partnerID=8YFLogxK
U2 - 10.1074/jbc.M204317200
DO - 10.1074/jbc.M204317200
M3 - Article
C2 - 12119289
AN - SCOPUS:0037184003
SN - 0021-9258
VL - 277
SP - 36748
EP - 36754
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 39
ER -