Response kinetics of tethered Rhodobacter sphaeroides to changes in light intensity.

Rhodobacter sphaeroides can swim toward a wide range of attractants (a process known as taxis), propelled by a single rotating flagellum. The reversals of motor direction that cause tumbles in Eschericia coli taxis are replaced by brief motor stops, and taxis is controlled by a complex sensory syste...

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Main Authors: Berry, R, Armitage, J
Format: Journal article
Language:English
Published: 2000
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author Berry, R
Armitage, J
author_facet Berry, R
Armitage, J
author_sort Berry, R
collection OXFORD
description Rhodobacter sphaeroides can swim toward a wide range of attractants (a process known as taxis), propelled by a single rotating flagellum. The reversals of motor direction that cause tumbles in Eschericia coli taxis are replaced by brief motor stops, and taxis is controlled by a complex sensory system with multiple homologues of the E. coli sensory proteins. We tethered photosynthetically grown cells of R. sphaeroides by their flagella and measured the response of the flagellar motor to changes in light intensity. The unstimulated bias (probability of not being stopped) was significantly larger than the bias of tethered E. coli but similar to the probability of not tumbling in swimming E. coli. Otherwise, the step and impulse responses were the same as those of tethered E. coli to chemical attractants. This indicates that the single motor and multiple sensory signaling pathways in R. sphaeroides generate the same swimming response as several motors and a single pathway in E. coli, and that the response of the single motor is directly observable in the swimming pattern. Photo-responses were larger in the presence of cyanide or the uncoupler carbonyl cyanide 4-trifluoromethoxyphenylhydrazone (FCCP), consistent with the photo-response being detected via changes in the rate of electron transport.
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spelling oxford-uuid:97a41146-5cc6-40fb-b1e0-b08bcb4c628d2022-03-27T00:01:22ZResponse kinetics of tethered Rhodobacter sphaeroides to changes in light intensity.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:97a41146-5cc6-40fb-b1e0-b08bcb4c628dEnglishSymplectic Elements at Oxford2000Berry, RArmitage, JRhodobacter sphaeroides can swim toward a wide range of attractants (a process known as taxis), propelled by a single rotating flagellum. The reversals of motor direction that cause tumbles in Eschericia coli taxis are replaced by brief motor stops, and taxis is controlled by a complex sensory system with multiple homologues of the E. coli sensory proteins. We tethered photosynthetically grown cells of R. sphaeroides by their flagella and measured the response of the flagellar motor to changes in light intensity. The unstimulated bias (probability of not being stopped) was significantly larger than the bias of tethered E. coli but similar to the probability of not tumbling in swimming E. coli. Otherwise, the step and impulse responses were the same as those of tethered E. coli to chemical attractants. This indicates that the single motor and multiple sensory signaling pathways in R. sphaeroides generate the same swimming response as several motors and a single pathway in E. coli, and that the response of the single motor is directly observable in the swimming pattern. Photo-responses were larger in the presence of cyanide or the uncoupler carbonyl cyanide 4-trifluoromethoxyphenylhydrazone (FCCP), consistent with the photo-response being detected via changes in the rate of electron transport.
spellingShingle Berry, R
Armitage, J
Response kinetics of tethered Rhodobacter sphaeroides to changes in light intensity.
title Response kinetics of tethered Rhodobacter sphaeroides to changes in light intensity.
title_full Response kinetics of tethered Rhodobacter sphaeroides to changes in light intensity.
title_fullStr Response kinetics of tethered Rhodobacter sphaeroides to changes in light intensity.
title_full_unstemmed Response kinetics of tethered Rhodobacter sphaeroides to changes in light intensity.
title_short Response kinetics of tethered Rhodobacter sphaeroides to changes in light intensity.
title_sort response kinetics of tethered rhodobacter sphaeroides to changes in light intensity
work_keys_str_mv AT berryr responsekineticsoftetheredrhodobactersphaeroidestochangesinlightintensity
AT armitagej responsekineticsoftetheredrhodobactersphaeroidestochangesinlightintensity