Bacillus subtilis CheN, a homolog of CheA, the central regulator of chemotaxis in Escherichia coli.
The Bacillus subtilis cheN gene was isolated, sequenced, and expressed. It encodes a large negatively charged protein with a molecular weight of approximately 74,000. The predicted protein sequence has 33 to 34% identity with the Escherichia coli and Salmonella typhimurium CheA and Myxococcus xanthus FrzE sequences. These proteins are found to autophosphorylate and are members of the same histidine kinase signal modulating family. CheN has several conserved regions (including the histidine that is phosphorylated in CheA) that coincide with other autophosphorylated signal transducers. A null mutant is defective in attractant-induced methanol formation and shows no behavioral response to chemoeffectors. These results imply that in B. subtilis the mechanism of chemotaxis involves phosphoryl transfer similar to that in E. coli. However, the CheN null mutant mostly tumbles, whereas CheA mutants swim smoothly, and only in B. subtilis does excitation lead to methyl transfer and methanol formation. Thus, the overall mechanism of chemotaxis is different in the two organisms.
Fuhrer
D K
DK
Department of Biochemistry, College of Medicine, University of Illinois, Urbana 61801.
Ordal
G W
GW
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000235:genetics* / Q000502:physiology; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D002630:Chemotactic Factors / Q000235:genetics*; D002633:Chemotaxis / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics* / Q000502:physiology; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D000071677:Histidine Kinase; D008565:Membrane Proteins / Q000235:genetics*; D000072236:Methyl-Accepting Chemotaxis Proteins; D008969:Molecular Sequence Data; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid
D001426:Bacterial Proteins; D002630:Chemotactic Factors; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins; C071722:CheN protein, Bacillus subtilis; D000071677:Histidine Kinase; C000607608:cheA protein, E coli