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@PHDTHESIS{Helfrich:809222,
author = {Helfrich, Stefan},
title = {{H}igh-{T}hroughput {L}ive-{C}ell {I}maging for
{I}nvestigations of {C}ellular {H}eterogeneity in
{C}orynebacterium glutamicum},
volume = {130},
school = {RWTH Aachen},
type = {Dr.},
address = {Jülich},
publisher = {Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag},
reportid = {FZJ-2016-02512},
isbn = {978-3-95806-167-5},
series = {Schriften des Forschungszentrums Jülich. Reihe
Schlüsseltechnologien / Key Technologies},
pages = {XVI, 217 S.},
year = {2016},
note = {RWTH Aachen, Diss., 2016},
abstract = {Significant cell-to-cell variation with respect to growth,
stress resistance, and other cellular traits are observed in
clonal microbial populations [1]. Advances in lab-on-a-chip
research and time-lapse microscopy have recently extended
the experimental capabilities to observe the development of
individual cells with unprecedented spatial and temporal
resolution. In combination with appropriate cultivation
devices, e.g., custom microfluidic lab-on-a-chip devices
[2], image sequences are acquired for hundreds of developing
populations in parallel under controlled environmental
conditions. With the possibility to generate such
large-scale datasets, the role of image analysis has become
a crucial step for the elicitation of quantitative,
time-resolved information for direct interpretation as well
as modeling purposes. We have developed an extensible image
analysis pipeline for the evaluation of time-lapse videos of
the industrially competitive amino-acid producer
$\textit{Corynebacterium glutamicum}$. The pipeline has been
optimized for the identification of cells in crowded
environments, tracking of cells with large spatial
displacements, and the extraction of a multitude of cellular
characteristics, for instance, cell morphology and
fluorescence reporter intensities. The presented pipeline is
implemented as a plugin for the well established ImageJ(2)
platform. The platform provides advanced data structures and
allows for visual controls of workflow composition and
parameters. The underlying service architecture promotes
extensibility of modules and flexibility to use
implementations in alternative contexts. The combination of
microfluidic system, live-cell imaging setup, and image
analysis techniques is capable to address challenges of
population heterogeneity in microbial populations even at
low temporal resolution. While the analysis platform has
been applied for a variety of studies, applications from two
fields are highlighted in this thesis. First, investigations
of microbial growth and morphology of $\textit{C.
glutamicum}$. Here, the applicability of growth
quantification methods from bulk experiments to single-cell
data are investigated. A second application transfers this
knowledge to a profiling study of $\textit{C. glutamicum}$
in which the influence of medium composition (i.e., carbon
sources) on growth and morphology parameters is analyzed.
Furthermore, an analysis of the microbial SOS response and
the induction of aprophage in C. glutamicum is presented. To
that end, a dual reporter strain (i.e.,reporters for SOS
response and prophage induction) is cultivated in
lab-on-a-chip devices and analyzed using fluorescence
microscopy. From the time-resolved reporter outputs, we have
established a cellular state model that is used for
comprehensive population modeling.},
cin = {IBG-1},
cid = {I:(DE-Juel1)IBG-1-20101118},
pnm = {581 - Biotechnology (POF3-581)},
pid = {G:(DE-HGF)POF3-581},
typ = {PUB:(DE-HGF)11},
urn = {urn:nbn:de:0001-2017040706},
url = {https://juser.fz-juelich.de/record/809222},
}