Inoculum Concentration Influences Pseudomonas aeruginosa Phenotype and Biofilm Architecture

Research output: Contribution to journalJournal articlepeer-review

Standard

Inoculum Concentration Influences Pseudomonas aeruginosa Phenotype and Biofilm Architecture. / Lichtenberg, Mads; Kvich, Lasse; Larsen, Sara Louise Borregaard; Jakobsen, Tim Holm; Bjarnsholt, Thomas.

In: Microbiology Spectrum, Vol. 10, No. 6, 2022.

Research output: Contribution to journalJournal articlepeer-review

Harvard

Lichtenberg, M, Kvich, L, Larsen, SLB, Jakobsen, TH & Bjarnsholt, T 2022, 'Inoculum Concentration Influences Pseudomonas aeruginosa Phenotype and Biofilm Architecture', Microbiology Spectrum, vol. 10, no. 6. https://doi.org/10.1128/spectrum.03131-22

APA

Lichtenberg, M., Kvich, L., Larsen, S. L. B., Jakobsen, T. H., & Bjarnsholt, T. (2022). Inoculum Concentration Influences Pseudomonas aeruginosa Phenotype and Biofilm Architecture. Microbiology Spectrum, 10(6). https://doi.org/10.1128/spectrum.03131-22

Vancouver

Lichtenberg M, Kvich L, Larsen SLB, Jakobsen TH, Bjarnsholt T. Inoculum Concentration Influences Pseudomonas aeruginosa Phenotype and Biofilm Architecture. Microbiology Spectrum. 2022;10(6). https://doi.org/10.1128/spectrum.03131-22

Author

Lichtenberg, Mads ; Kvich, Lasse ; Larsen, Sara Louise Borregaard ; Jakobsen, Tim Holm ; Bjarnsholt, Thomas. / Inoculum Concentration Influences Pseudomonas aeruginosa Phenotype and Biofilm Architecture. In: Microbiology Spectrum. 2022 ; Vol. 10, No. 6.

Bibtex

@article{2abd62d5462048c79c7da98eb96f1e56,
title = "Inoculum Concentration Influences Pseudomonas aeruginosa Phenotype and Biofilm Architecture",
abstract = "In infections, bacterial cells are often found as relatively small multicellular aggregates characterized by a heterogeneous distribution of phenotype, genotype, and growth rates depending on their surrounding microenvironment. Many laboratory models fail to mimic these characteristics, and experiments are often initiated from planktonic bacteria given optimal conditions for rapid growth without concerns about the microenvironmental characteristics during biofilm maturation. Therefore, we investigated how the initial bacterial concentration (henceforth termed the inoculum) influences the microenvironment during initial growth and how this affects the sizes and distribution of developed aggregates in an embedded biofilm model—the alginate bead biofilm model. Following 24 h of incubation, the viable biomass was independent of starting inoculum but with a radically different microenvironment which led to differences in metabolic activity depending on the inoculum. The inoculum also affected the number of cells surviving treatment with the antibiotic tobramycin, where the highest inoculum showed higher survival rates than the lowest inoculum. The change in antibiotic tolerance was correlated with cell-specific RNA content and O2 consumption rates, suggesting a direct role of metabolic activity. Thus, the starting number of bacteria results in different phenotypic trajectories governed by different microenvironmental characteristics, and we demonstrate some of the possible implications of such physiological gradients on the outcome of in vitro experiments.",
keywords = "alginate bead, biofilm, microenvironment, model system, oxygen, Pseudomonas aeruginosa, spatial structure",
author = "Mads Lichtenberg and Lasse Kvich and Larsen, {Sara Louise Borregaard} and Jakobsen, {Tim Holm} and Thomas Bjarnsholt",
note = "Publisher Copyright: Copyright {\textcopyright} 2022 Lichtenberg et al.",
year = "2022",
doi = "10.1128/spectrum.03131-22",
language = "English",
volume = "10",
journal = "Microbiology spectrum",
issn = "2165-0497",
publisher = "American Society for Microbiology",
number = "6",

}

RIS

TY - JOUR

T1 - Inoculum Concentration Influences Pseudomonas aeruginosa Phenotype and Biofilm Architecture

AU - Lichtenberg, Mads

AU - Kvich, Lasse

AU - Larsen, Sara Louise Borregaard

AU - Jakobsen, Tim Holm

AU - Bjarnsholt, Thomas

N1 - Publisher Copyright: Copyright © 2022 Lichtenberg et al.

PY - 2022

Y1 - 2022

N2 - In infections, bacterial cells are often found as relatively small multicellular aggregates characterized by a heterogeneous distribution of phenotype, genotype, and growth rates depending on their surrounding microenvironment. Many laboratory models fail to mimic these characteristics, and experiments are often initiated from planktonic bacteria given optimal conditions for rapid growth without concerns about the microenvironmental characteristics during biofilm maturation. Therefore, we investigated how the initial bacterial concentration (henceforth termed the inoculum) influences the microenvironment during initial growth and how this affects the sizes and distribution of developed aggregates in an embedded biofilm model—the alginate bead biofilm model. Following 24 h of incubation, the viable biomass was independent of starting inoculum but with a radically different microenvironment which led to differences in metabolic activity depending on the inoculum. The inoculum also affected the number of cells surviving treatment with the antibiotic tobramycin, where the highest inoculum showed higher survival rates than the lowest inoculum. The change in antibiotic tolerance was correlated with cell-specific RNA content and O2 consumption rates, suggesting a direct role of metabolic activity. Thus, the starting number of bacteria results in different phenotypic trajectories governed by different microenvironmental characteristics, and we demonstrate some of the possible implications of such physiological gradients on the outcome of in vitro experiments.

AB - In infections, bacterial cells are often found as relatively small multicellular aggregates characterized by a heterogeneous distribution of phenotype, genotype, and growth rates depending on their surrounding microenvironment. Many laboratory models fail to mimic these characteristics, and experiments are often initiated from planktonic bacteria given optimal conditions for rapid growth without concerns about the microenvironmental characteristics during biofilm maturation. Therefore, we investigated how the initial bacterial concentration (henceforth termed the inoculum) influences the microenvironment during initial growth and how this affects the sizes and distribution of developed aggregates in an embedded biofilm model—the alginate bead biofilm model. Following 24 h of incubation, the viable biomass was independent of starting inoculum but with a radically different microenvironment which led to differences in metabolic activity depending on the inoculum. The inoculum also affected the number of cells surviving treatment with the antibiotic tobramycin, where the highest inoculum showed higher survival rates than the lowest inoculum. The change in antibiotic tolerance was correlated with cell-specific RNA content and O2 consumption rates, suggesting a direct role of metabolic activity. Thus, the starting number of bacteria results in different phenotypic trajectories governed by different microenvironmental characteristics, and we demonstrate some of the possible implications of such physiological gradients on the outcome of in vitro experiments.

KW - alginate bead

KW - biofilm

KW - microenvironment

KW - model system

KW - oxygen

KW - Pseudomonas aeruginosa

KW - spatial structure

U2 - 10.1128/spectrum.03131-22

DO - 10.1128/spectrum.03131-22

M3 - Journal article

C2 - 36354337

AN - SCOPUS:85144635991

VL - 10

JO - Microbiology spectrum

JF - Microbiology spectrum

SN - 2165-0497

IS - 6

ER -

ID: 333619337