Inversion of aerotactic response in Escherichia coli deficient in cheB protein methylesterase.
AUTOR(ES)
Dang, C V
RESUMO
Mutants of Escherichia coli and Salmonella typhimurium that were deficient in protein methylesterase activity encoded by cheB had an inverted response to oxygen; they were repelled by concentrations of oxygen that attract wild-type bacteria. Normal responses to oxygen and phosphotransferase substrates were observed in mutants that were deficient in protein methyltransferase (CheR) and the methyl-accepting transducing proteins (Tsr, Tar, Trg). However, the methylation-independent response to oxygen was modified by the loss of esterase activity. The inversion was apparently effected by the amidated Tsr protein present in cheB tsr+ mutants because aerotaxis was normal in cheB tsr strains. Chemotaxis to phosphotransferase sugars was normal in cheB mutants provided the extreme clockwise bias of the flagellar motors was modified to increase the probability of counterclockwise rotation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=214587Documentos Relacionados
- N-terminal half of CheB is involved in methylesterase response to negative chemotactic stimuli in Escherichia coli.
- Clustering of the Chemoreceptor Complex in Escherichia coli Is Independent of the Methyltransferase CheR and the Methylesterase CheB
- Structural basis for methylesterase CheB regulation by a phosphorylation-activated domain
- Requirement of the cheB function for sensory adaptation in Escherichia coli.
- Mutations that affect control of the methylesterase activity of CheB, a component of the chemotaxis adaptation system in Escherichia coli.