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Updated: Jun 28, 2026
07:04
Determination of the Glycogen Content in Cyanobacteria
Published on: July 17, 2017
Glucose uptake and its effect on gene expression in prochlorococcus
Guadalupe Gómez-Baena1, Antonio López-Lozano, Jorge Gil-Martínez
1Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, Campus de Rabanales, Universidad de Córdoba, Córdoba, Spain.
Plos One
|October 23, 2008
Summary
Marine Prochlorococcus, vital for global primary production, can now be confirmed to actively uptake glucose. This finding reveals a new carbon assimilation pathway for these key phytoplankton, impacting our understanding of the marine carbon cycle.
Area of Science:
- Marine microbiology
- Oceanography
- Biogeochemical cycles
Background:
- Prochlorococcus are globally significant marine cyanobacteria, primarily considered photoautotrophic.
- The ability of Prochlorococcus to utilize exogenous sugars, like glucose, has not been previously investigated.
Purpose of the Study:
- To investigate glucose uptake in different Prochlorococcus strains.
- To determine the effect of glucose addition on the expression of glucose-related genes in Prochlorococcus.
Main Methods:
- Radiolabeled glucose was added to Prochlorococcus cultures.
- Flow cytometry and cell sorting were used to isolate Prochlorococcus cells from contaminants.
- Radioactivity measurements quantified glucose uptake.
- Semi-quantitative real-time RT-PCR analyzed gene expression changes in response to glucose.
Main Results:
- Prochlorococcus strains demonstrated significant glucose uptake at environmentally relevant concentrations.
- Gene expression analysis showed increased activity of glucose utilization genes (zwf, gnd, dld) after glucose addition.
- Contamination by other bacteria was ruled out as the source of glucose uptake.
Conclusions:
- This study provides the first evidence of direct glucose assimilation by Prochlorococcus.
- The findings highlight the physiological importance of heterotrophic capabilities in Prochlorococcus.
- This assimilation pathway has significant implications for understanding the role of Prochlorococcus in the marine carbon cycle and their ecological success.
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