Role of methylation in aerotaxis in Bacillus subtilis.
Taxis to oxygen (aerotaxis) in Bacillus subtilis was characterized in a capillary assay and in a temporal assay in which the concentration of oxygen in a flow chamber was changed abruptly. A strong aerophilic response was present, but there was no aerophobic response to high concentrations of oxygen. Adaptation to a step increase in oxygen concentration was impaired when B. subtilis cells were depleted of methionine to prevent methylation of the methyl-accepting chemotaxis proteins. There was a transient increase in methanol release when wild-type B. subtilis, but not a cheR mutant that was deficient in methyltransferase activity, was stimulated by a step increase or a step decrease in oxygen concentration. The methanol released was quantitatively correlated with demethylation of methyl-accepting chemotaxis proteins. This indicated that methylation is involved in aerotaxis in B. subtilis in contrast to aerotaxis in Escherichia coli and Salmonella typhimurium, which is methylation independent.
Wong
L S
LS
Department of Microbiology and Molecular Genetics, Loma Linda University, California 92350, USA.
Johnson
M S
MS
Zhulin
I B
IB
Taylor
B L
BL
D000332:Aerobiosis; D000693:Anaerobiosis; D001412:Bacillus subtilis / Q000502:physiology*; D001426:Bacterial Proteins; D002633:Chemotaxis / Q000502:physiology*; D008565:Membrane Proteins / Q000378:metabolism*; D000432:Methanol / Q000378:metabolism; D008715:Methionine / Q000378:metabolism; D000072236:Methyl-Accepting Chemotaxis Proteins; D008745:Methylation; D008780:Methyltransferases / Q000235:genetics; D009154:Mutation
D001426:Bacterial Proteins; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins; D008715:Methionine; D008780:Methyltransferases; C038706:chemotaxis methyltransferase; D000432:Methanol