Quantitative Flow Cytometry to Understand Population Heterogeneity in Response to Changes in Substrate Availability in Escherichia coli and Saccharomyces cerevisiae Chemostats

Anna-Lena Heins*, Ted Johanson, Shanshan Han, Luisa Lundin, Magnus Carlquist, Krist V. Gemaey, Søren J. Sørensen, Anna Eliasson Lantz

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

63 Downloads (Pure)

Abstract

Microbial cells in bioprocesses are usually described with averaged parameters. But in fact, single cells within populations vary greatly in characteristics such as stress resistance, especially in response to carbon source gradients. Our aim was to introduce tools to quantify population heterogeneity in bioprocesses using a combination of reporter strains, flow cytometry, and easily comprehensible parameters. We calculated mean, mode, peak width, and coefficient of variance to describe distribution characteristics and temporal shifts in fluorescence intensity. The skewness and the slope of cumulative distribution function plots illustrated differences in distribution shape. These parameters are person-independent and precise. We demonstrated this by quantifying growth-related population heterogeneity of Saccharomyces cerevisiae and Escherichia coli reporter strains in steady-state of aerobic glucose-limited chemostat cultures at different dilution rates and in response to glucose pulses. Generally, slow-growing cells showed stronger responses to glucose excess than fast-growing cells. Cell robustness, measured as membrane integrity after exposure to freeze-thaw treatment, of fast-growing cells was strongly affected in subpopulations of low membrane robustness. Glucose pulses protected subpopulations of fast-growing but not slower-growing yeast cells against membrane damage. Our parameters could successfully describe population heterogeneity, thereby revealing physiological characteristics that might have been overlooked during traditional averaged analysis.
Original languageEnglish
Article number187
JournalFrontiers in Bioengineering and Biotechnology
Volume7
Number of pages15
ISSN2296-4185
DOIs
Publication statusPublished - 2019

Bibliographical note

Copyright © 2019 Heins, Johanson, Han, Lundin, Carlquist, Gernaey, Sørensen and Eliasson Lantz. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

Keywords

  • Population heterogeneity
  • Quantitative flow cytometry
  • Glucose pulse
  • Reporter strain
  • Membrane robustness
  • Flow cytometry

Cite this

@article{7324632cdaa843c0969a48456d71104b,
title = "Quantitative Flow Cytometry to Understand Population Heterogeneity in Response to Changes in Substrate Availability in Escherichia coli and Saccharomyces cerevisiae Chemostats",
abstract = "Microbial cells in bioprocesses are usually described with averaged parameters. But in fact, single cells within populations vary greatly in characteristics such as stress resistance, especially in response to carbon source gradients. Our aim was to introduce tools to quantify population heterogeneity in bioprocesses using a combination of reporter strains, flow cytometry, and easily comprehensible parameters. We calculated mean, mode, peak width, and coefficient of variance to describe distribution characteristics and temporal shifts in fluorescence intensity. The skewness and the slope of cumulative distribution function plots illustrated differences in distribution shape. These parameters are person-independent and precise. We demonstrated this by quantifying growth-related population heterogeneity of Saccharomyces cerevisiae and Escherichia coli reporter strains in steady-state of aerobic glucose-limited chemostat cultures at different dilution rates and in response to glucose pulses. Generally, slow-growing cells showed stronger responses to glucose excess than fast-growing cells. Cell robustness, measured as membrane integrity after exposure to freeze-thaw treatment, of fast-growing cells was strongly affected in subpopulations of low membrane robustness. Glucose pulses protected subpopulations of fast-growing but not slower-growing yeast cells against membrane damage. Our parameters could successfully describe population heterogeneity, thereby revealing physiological characteristics that might have been overlooked during traditional averaged analysis.",
keywords = "Population heterogeneity, Quantitative flow cytometry, Glucose pulse, Reporter strain, Membrane robustness, Flow cytometry",
author = "Anna-Lena Heins and Ted Johanson and Shanshan Han and Luisa Lundin and Magnus Carlquist and Gemaey, {Krist V.} and S{\o}rensen, {S{\o}ren J.} and {Eliasson Lantz}, Anna",
note = "Copyright {\circledC} 2019 Heins, Johanson, Han, Lundin, Carlquist, Gernaey, S{\o}rensen and Eliasson Lantz. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.",
year = "2019",
doi = "10.3389/fbioe.2019.00187",
language = "English",
volume = "7",
journal = "Frontiers in Bioengineering and Biotechnology",
issn = "2296-4185",
publisher = "Frontiers Media",

}

Quantitative Flow Cytometry to Understand Population Heterogeneity in Response to Changes in Substrate Availability in Escherichia coli and Saccharomyces cerevisiae Chemostats. / Heins, Anna-Lena; Johanson, Ted; Han, Shanshan; Lundin, Luisa; Carlquist, Magnus; Gemaey, Krist V.; Sørensen, Søren J.; Eliasson Lantz, Anna.

In: Frontiers in Bioengineering and Biotechnology, Vol. 7, 187, 2019.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Quantitative Flow Cytometry to Understand Population Heterogeneity in Response to Changes in Substrate Availability in Escherichia coli and Saccharomyces cerevisiae Chemostats

AU - Heins, Anna-Lena

AU - Johanson, Ted

AU - Han, Shanshan

AU - Lundin, Luisa

AU - Carlquist, Magnus

AU - Gemaey, Krist V.

AU - Sørensen, Søren J.

AU - Eliasson Lantz, Anna

N1 - Copyright © 2019 Heins, Johanson, Han, Lundin, Carlquist, Gernaey, Sørensen and Eliasson Lantz. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

PY - 2019

Y1 - 2019

N2 - Microbial cells in bioprocesses are usually described with averaged parameters. But in fact, single cells within populations vary greatly in characteristics such as stress resistance, especially in response to carbon source gradients. Our aim was to introduce tools to quantify population heterogeneity in bioprocesses using a combination of reporter strains, flow cytometry, and easily comprehensible parameters. We calculated mean, mode, peak width, and coefficient of variance to describe distribution characteristics and temporal shifts in fluorescence intensity. The skewness and the slope of cumulative distribution function plots illustrated differences in distribution shape. These parameters are person-independent and precise. We demonstrated this by quantifying growth-related population heterogeneity of Saccharomyces cerevisiae and Escherichia coli reporter strains in steady-state of aerobic glucose-limited chemostat cultures at different dilution rates and in response to glucose pulses. Generally, slow-growing cells showed stronger responses to glucose excess than fast-growing cells. Cell robustness, measured as membrane integrity after exposure to freeze-thaw treatment, of fast-growing cells was strongly affected in subpopulations of low membrane robustness. Glucose pulses protected subpopulations of fast-growing but not slower-growing yeast cells against membrane damage. Our parameters could successfully describe population heterogeneity, thereby revealing physiological characteristics that might have been overlooked during traditional averaged analysis.

AB - Microbial cells in bioprocesses are usually described with averaged parameters. But in fact, single cells within populations vary greatly in characteristics such as stress resistance, especially in response to carbon source gradients. Our aim was to introduce tools to quantify population heterogeneity in bioprocesses using a combination of reporter strains, flow cytometry, and easily comprehensible parameters. We calculated mean, mode, peak width, and coefficient of variance to describe distribution characteristics and temporal shifts in fluorescence intensity. The skewness and the slope of cumulative distribution function plots illustrated differences in distribution shape. These parameters are person-independent and precise. We demonstrated this by quantifying growth-related population heterogeneity of Saccharomyces cerevisiae and Escherichia coli reporter strains in steady-state of aerobic glucose-limited chemostat cultures at different dilution rates and in response to glucose pulses. Generally, slow-growing cells showed stronger responses to glucose excess than fast-growing cells. Cell robustness, measured as membrane integrity after exposure to freeze-thaw treatment, of fast-growing cells was strongly affected in subpopulations of low membrane robustness. Glucose pulses protected subpopulations of fast-growing but not slower-growing yeast cells against membrane damage. Our parameters could successfully describe population heterogeneity, thereby revealing physiological characteristics that might have been overlooked during traditional averaged analysis.

KW - Population heterogeneity

KW - Quantitative flow cytometry

KW - Glucose pulse

KW - Reporter strain

KW - Membrane robustness

KW - Flow cytometry

U2 - 10.3389/fbioe.2019.00187

DO - 10.3389/fbioe.2019.00187

M3 - Journal article

C2 - 31448270

VL - 7

JO - Frontiers in Bioengineering and Biotechnology

JF - Frontiers in Bioengineering and Biotechnology

SN - 2296-4185

M1 - 187

ER -