The response of cells to changes in their physico-chemical
micro-environment is essential to their survival. For example, bacterial
magnetotaxis uses the Earth's magnetic field together with chemical
sensing to help microorganisms move towards favoured habitats. The
studies of such complex responses are lacking a method that permits the
simultaneous mapping of the chemical environment and the response of the
organisms, and the ability to generate a controlled physiological
magnetic field. We have thus developed a multi-modal microscopy platform
that fulfils these requirements. Using simultaneous fluorescence and
high-speed imaging in conjunction with diffusion and aerotactic models,
we characterized the magneto-aerotaxis of Magnetospirillum gryph is
waldense. We assessed the influence of the magnetic field (orientation;
strength) on the formation and the dynamic of a micro-aerotactic band
(size, dynamic, position). As previously described by models of
magnetotaxis, the application of a magnetic field pointing towards the
anoxic zone of an oxygen gradient results in an enhanced aerotaxis even
down to Earth's magnetic field strength. We found that neither a
ten-fold increase of the field strength nor a tilt of 45 degrees
resulted in a significant change of the aerotactic efficiency. However,
when the field strength is zeroed or when the field angle is tilted to
90 degrees, the magneto-aerotaxis efficiency is drastically reduced. The
classical model of magneto-aerotaxis assumes a response proportional to
the cosine of the angle difference between the directions of the oxygen
gradient and that of the magnetic field. Our experimental evidence
however shows that this behaviour is more complex than assumed in this
model, thus opening up new avenues for research.
The research was supported by the Max Planck Society and the ERC through
a Starting Grant to DaF (256915-MB2). AMcC and GSB acknowledge the
support of the UK Engineering and Physical Sciences Research Council.
MRE and MS acknowledge the support of the National Science Foundation
under a CPS Medium Project (CNS-1135850) and of the National Science
Foundation Graduate Research Fellowship Program under Grant No.
0946825I. The funders had no role in study design, data collection and
analysis, decision to publish, or preparation of the manuscript.
funding-acknowledgement
Max Planck Society; ERC through a Starting Grant 256915-MB2; UK
Engineering and Physical Sciences Research Council; National Science
Foundation under a CPS Medium Project CNS-1135850; National Science
Foundation Graduate Research Fellowship Program 0946825I
%0 Journal Article
%1 ISI:000339635000058
%A Bennet, Mathieu
%A McCarthy, Aongus
%A Fix, Dmitri
%A Edwards, Matthew R.
%A Repp, Felix
%A Vach, Peter
%A Dunlop, John W. C.
%A Sitti, Metin
%A Buller, Gerald S.
%A Klumpp, Stefan
%A Faivre, Damien
%C 1160 BATTERY STREET, STE 100, SAN FRANCISCO, CA 94111 USA
%D 2014
%I PUBLIC LIBRARY SCIENCE
%J PLOS ONE
%K felixrepp
%N 7
%R 10.1371/journal.pone.0101150
%T Influence of Magnetic Fields on Magneto-Aerotaxis
%V 9
%X The response of cells to changes in their physico-chemical
micro-environment is essential to their survival. For example, bacterial
magnetotaxis uses the Earth's magnetic field together with chemical
sensing to help microorganisms move towards favoured habitats. The
studies of such complex responses are lacking a method that permits the
simultaneous mapping of the chemical environment and the response of the
organisms, and the ability to generate a controlled physiological
magnetic field. We have thus developed a multi-modal microscopy platform
that fulfils these requirements. Using simultaneous fluorescence and
high-speed imaging in conjunction with diffusion and aerotactic models,
we characterized the magneto-aerotaxis of Magnetospirillum gryph is
waldense. We assessed the influence of the magnetic field (orientation;
strength) on the formation and the dynamic of a micro-aerotactic band
(size, dynamic, position). As previously described by models of
magnetotaxis, the application of a magnetic field pointing towards the
anoxic zone of an oxygen gradient results in an enhanced aerotaxis even
down to Earth's magnetic field strength. We found that neither a
ten-fold increase of the field strength nor a tilt of 45 degrees
resulted in a significant change of the aerotactic efficiency. However,
when the field strength is zeroed or when the field angle is tilted to
90 degrees, the magneto-aerotaxis efficiency is drastically reduced. The
classical model of magneto-aerotaxis assumes a response proportional to
the cosine of the angle difference between the directions of the oxygen
gradient and that of the magnetic field. Our experimental evidence
however shows that this behaviour is more complex than assumed in this
model, thus opening up new avenues for research.
@article{ISI:000339635000058,
abstract = {{The response of cells to changes in their physico-chemical
micro-environment is essential to their survival. For example, bacterial
magnetotaxis uses the Earth's magnetic field together with chemical
sensing to help microorganisms move towards favoured habitats. The
studies of such complex responses are lacking a method that permits the
simultaneous mapping of the chemical environment and the response of the
organisms, and the ability to generate a controlled physiological
magnetic field. We have thus developed a multi-modal microscopy platform
that fulfils these requirements. Using simultaneous fluorescence and
high-speed imaging in conjunction with diffusion and aerotactic models,
we characterized the magneto-aerotaxis of Magnetospirillum gryph is
waldense. We assessed the influence of the magnetic field (orientation;
strength) on the formation and the dynamic of a micro-aerotactic band
(size, dynamic, position). As previously described by models of
magnetotaxis, the application of a magnetic field pointing towards the
anoxic zone of an oxygen gradient results in an enhanced aerotaxis even
down to Earth's magnetic field strength. We found that neither a
ten-fold increase of the field strength nor a tilt of 45 degrees
resulted in a significant change of the aerotactic efficiency. However,
when the field strength is zeroed or when the field angle is tilted to
90 degrees, the magneto-aerotaxis efficiency is drastically reduced. The
classical model of magneto-aerotaxis assumes a response proportional to
the cosine of the angle difference between the directions of the oxygen
gradient and that of the magnetic field. Our experimental evidence
however shows that this behaviour is more complex than assumed in this
model, thus opening up new avenues for research.}},
added-at = {2017-07-17T13:25:19.000+0200},
address = {{1160 BATTERY STREET, STE 100, SAN FRANCISCO, CA 94111 USA}},
affiliation = {{Faivre, D (Reprint Author), Max Planck Inst Colloids \& Interfaces, Dept Biomat, Sci Pk Golm, Potsdam, Germany.
Bennet, Mathieu; Fix, Dmitri; Repp, Felix; Vach, Peter; Dunlop, John W. C.; Faivre, Damien, Max Planck Inst Colloids \& Interfaces, Dept Biomat, Potsdam, Germany.
McCarthy, Aongus; Buller, Gerald S., Heriot Watt Univ, Sch Engn \& Phys Sci, Inst Photon \& Quantum Sci, Edinburgh, Midlothian, Scotland.
McCarthy, Aongus; Buller, Gerald S., Heriot Watt Univ, Sch Engn \& Phys Sci, SUPA, Edinburgh, Midlothian, Scotland.
Edwards, Matthew R.; Sitti, Metin, Carnegie Mellon Univ, Dept Mech Engn, Pittsburgh, PA 15213 USA.
Klumpp, Stefan, Max Planck Inst Colloids \& Interfaces, Dept Theory \& Biosyst, Potsdam, Germany.}},
article-number = {{e101150}},
author = {Bennet, Mathieu and McCarthy, Aongus and Fix, Dmitri and Edwards, Matthew R. and Repp, Felix and Vach, Peter and Dunlop, John W. C. and Sitti, Metin and Buller, Gerald S. and Klumpp, Stefan and Faivre, Damien},
author-email = {{Damien.Faivre@mpikg.mpg.de}},
biburl = {https://www.bibsonomy.org/bibtex/238c096afb7f0ee9004d23b6ba117efff/philipk},
da = {{2017-07-17}},
doc-delivery-number = {{AM1UX}},
doi = {{10.1371/journal.pone.0101150}},
funding-acknowledgement = {{Max Planck Society; ERC through a Starting Grant {[}256915-MB2]; UK
Engineering and Physical Sciences Research Council; National Science
Foundation under a CPS Medium Project {[}CNS-1135850]; National Science
Foundation Graduate Research Fellowship Program {[}0946825I]}},
funding-text = {{The research was supported by the Max Planck Society and the ERC through
a Starting Grant to DaF (256915-MB2). AMcC and GSB acknowledge the
support of the UK Engineering and Physical Sciences Research Council.
MRE and MS acknowledge the support of the National Science Foundation
under a CPS Medium Project (CNS-1135850) and of the National Science
Foundation Graduate Research Fellowship Program under Grant No.
0946825I. The funders had no role in study design, data collection and
analysis, decision to publish, or preparation of the manuscript.}},
interhash = {be35f5906d526256b52d9283e3a2769d},
intrahash = {38c096afb7f0ee9004d23b6ba117efff},
issn = {{1932-6203}},
journal = {{PLOS ONE}},
journal-iso = {{PLoS One}},
keywords = {felixrepp},
keywords-plus = {{BAND FORMATION; BACTERIA; OXYGEN; CHEMOTAXIS; RESPONSES}},
language = {{English}},
month = {{JUL 1}},
number = {{7}},
number-of-cited-references = {{30}},
oa = {{gold}},
orcid-numbers = {{faivre, damien/0000-0001-6191-3389
Klumpp, Stefan/0000-0003-0584-2146
Dunlop, John/0000-0003-2741-6383
Buller, Gerald/0000-0003-0441-2830}},
publisher = {{PUBLIC LIBRARY SCIENCE}},
research-areas = {{Science \& Technology - Other Topics}},
researcherid-numbers = {{faivre, damien/D-3713-2009
Klumpp, Stefan/C-2966-2008
Dunlop, John/A-1997-2012
}},
times-cited = {{15}},
timestamp = {2017-07-17T13:25:19.000+0200},
title = {{Influence of Magnetic Fields on Magneto-Aerotaxis}},
type = {{Article}},
unique-id = {{ISI:000339635000058}},
usage-count-last-180-days = {{4}},
usage-count-since-2013 = {{21}},
volume = {{9}},
web-of-science-categories = {{Multidisciplinary Sciences}},
year = {{2014}}
}