Publication detail

Accumulation of PHA granules in Cupriavidus necator as seen by confocal fluorescence microscopy

MRAVEC, F. OBRUČA, S. KRZYŽÁNEK, V. SEDLÁČEK, P. HRUBANOVÁ, K. SAMEK, O. KUČERA, D. BENEŠOVÁ, P. NEBESÁŘOVÁ, J.

Original Title

Accumulation of PHA granules in Cupriavidus necator as seen by confocal fluorescence microscopy

English Title

Accumulation of PHA granules in Cupriavidus necator as seen by confocal fluorescence microscopy

Type

journal article in Web of Science

Language

en

Original Abstract

Many bacteria are capable of accumulating intracellular granules of polyhydroxyalkanoates (PHA). In this work, we developed confocal microscopy analysis of bacterial cells to study changes in the diameters of cells as well as PHA granules during growth and PHA accumulation in the bacterium Cupriavidus necator H16 (formerly Ralstonia eutropha). The cell envelope was stained by DiD (R) fluorescent probe and PHA granules by Nile Red. Signals from both probes were separated based on their spectral and fluorescence life-time properties. During growth and PHA accumulation, bacterial cells increased their length but the width of the cells remained constant. The volume fraction of PHA granules in cells increased during PHA accumulation, nevertheless, its value did not exceed 40 vol. % regardless of the PHA weight content. It seems that bacterial cultures lengthen the cells in order to control the PHA volume portion. However, since similar changes in cell length were also observed in a PHA non-accumulating mutant, it seems that there is no direct control mechanism, which regulates the prolongation of the cells with respect to PHA granules volume. It is more likely that PHA biosynthesis and the length of cells are influenced by the same external stimuli such as nutrient limitation.

English abstract

Many bacteria are capable of accumulating intracellular granules of polyhydroxyalkanoates (PHA). In this work, we developed confocal microscopy analysis of bacterial cells to study changes in the diameters of cells as well as PHA granules during growth and PHA accumulation in the bacterium Cupriavidus necator H16 (formerly Ralstonia eutropha). The cell envelope was stained by DiD (R) fluorescent probe and PHA granules by Nile Red. Signals from both probes were separated based on their spectral and fluorescence life-time properties. During growth and PHA accumulation, bacterial cells increased their length but the width of the cells remained constant. The volume fraction of PHA granules in cells increased during PHA accumulation, nevertheless, its value did not exceed 40 vol. % regardless of the PHA weight content. It seems that bacterial cultures lengthen the cells in order to control the PHA volume portion. However, since similar changes in cell length were also observed in a PHA non-accumulating mutant, it seems that there is no direct control mechanism, which regulates the prolongation of the cells with respect to PHA granules volume. It is more likely that PHA biosynthesis and the length of cells are influenced by the same external stimuli such as nutrient limitation.

Keywords

Polyhydroxyalkanoates; intracellular granules; confocal fluorescence microscopy; bacterial cell diameters

Released

01.05.2016

Publisher

Oxford University Press

Pages from

1

Pages to

6

Pages count

7

URL

BibTex


@article{BUT126210,
  author="Filip {Mravec} and Stanislav {Obruča} and Vladislav {Krzyžánek} and Petr {Sedláček} and Kamila {Hrubanová} and Ota {Samek} and Dan {Kučera} and Pavla {Benešová} and Jana {Nebesářová}",
  title="Accumulation of PHA granules in Cupriavidus necator as seen by confocal fluorescence microscopy",
  annote="Many bacteria are capable of accumulating intracellular granules of polyhydroxyalkanoates (PHA). In this work, we developed confocal microscopy analysis of bacterial cells to study changes in the diameters of cells as well as PHA granules during growth and PHA accumulation in the bacterium Cupriavidus necator H16 (formerly Ralstonia eutropha). The cell envelope was stained by DiD (R) fluorescent probe and PHA granules by Nile Red. Signals from both probes were separated based on their spectral and fluorescence life-time properties. During growth and PHA accumulation, bacterial cells increased their length but the width of the cells remained constant. The volume fraction of PHA granules in cells increased during PHA accumulation, nevertheless, its value did not exceed 40 vol. % regardless of the PHA weight content. It seems that bacterial cultures lengthen the cells in order to control the PHA volume portion. However, since similar changes in cell length were also observed in a PHA non-accumulating mutant, it seems that there is no direct control mechanism, which regulates the prolongation of the cells with respect to PHA granules volume. It is more likely that PHA biosynthesis and the length of cells are influenced by the same external stimuli such as nutrient limitation.",
  address="Oxford University Press",
  chapter="126210",
  doi="10.1093/femsle/fnw094",
  institution="Oxford University Press",
  number="10",
  volume="363",
  year="2016",
  month="may",
  pages="1--6",
  publisher="Oxford University Press",
  type="journal article in Web of Science"
}