AEROTAXIS AND OTHER ENERGY-SENSING BEHAVIOR IN BACTERIA
Energy taxis is widespread in motile bacteria and in some species is the only known behavioral response. The bacteria monitor their cellular energy levels and respond to a decrease in energy by swimming to a microenvironment that reenergizes the cells. This is in contrast to classical Escherichia co...
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Published in | Annual review of microbiology Vol. 53; no. 1; pp. 103 - 128 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Palo Alto, CA 94303-0139
Annual Reviews
01.01.1999
4139 El Camino Way, P.O. Box 10139 Annual Reviews, Inc USA |
Subjects | |
Online Access | Get full text |
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Summary: | Energy taxis is widespread in motile bacteria and in some species is the
only known behavioral response. The bacteria monitor their cellular energy
levels and respond to a decrease in energy by swimming to a microenvironment
that reenergizes the cells. This is in contrast to classical
Escherichia
coli
chemotaxis in which sensing of stimuli is independent of cellular
metabolism. Energy taxis encompasses aerotaxis (taxis to oxygen), phototaxis,
redox taxis, taxis to alternative electron acceptors, and chemotaxis to a
carbon source. All of these responses share a common signal transduction
pathway. An environmental stimulus, such as oxygen concentration or light
intensity, modulates the flow of reducing equivalents through the electron
transport system. A transducer senses the change in electron transport, or
possibly a related parameter such as proton motive force, and initiates a
signal that alters the direction of swimming. The Aer and Tsr proteins in
E.
coli
are newly recognized transducers for energy taxis. Aer is homologous
to
E. coli
chemoreceptors but unique in having a PAS domain and a
flavin-adenine dinucleotide cofactor that is postulated to interact with a
component of the electron transport system. PAS domains are energy-sensing
modules that are found in proteins from archaea to humans. Tsr, the serine
chemoreceptor, is an independent transducer for energy taxis, but its sensory
mechanism is unknown. Energy taxis has a significant ecological role in
vertical stratification of microorganisms in microbial mats and water columns.
It plays a central role in the behavior of magnetotactic bacteria and also
appears to be important in plant-microbe interactions. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 ObjectType-Review-3 content type line 23 ObjectType-Article-1 ObjectType-Feature-3 ObjectType-Review-2 |
ISSN: | 0066-4227 1545-3251 |
DOI: | 10.1146/annurev.micro.53.1.103 |