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Updated: May 10, 2026
10:37
Single-cell Microfluidic Analysis of Bacillus subtilis
Published on: January 26, 2018
A single-cell perspective on non-growing but metabolically active (NGMA) bacteria
Giulia Manina1, John D McKinney
1School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), 1015, Lausanne, Switzerland, giulia.manina@epfl.ch.
Current Topics in Microbiology and Immunology
|June 25, 2013
Summary
Distinguishing live from dead bacterial cells is challenging. New real-time single-cell analysis technologies, including microfluidics and fluorescence microscopy, offer promising methods to study non-growing but metabolically active cells.
Area of Science:
- Microbiology
- Cell Biology
- Molecular Biology
Background:
- Discriminating between live and dead cells is a fundamental challenge in microbiology.
- Physically intact bacterial cells may fail to replicate under favorable conditions, entering a viable but non-culturable (VBNC) state.
- VBNC cells, particularly Mycobacterium tuberculosis, can cause persistent infections and reactivate after latency.
Purpose of the Study:
- To highlight the potential of novel technologies for studying non-growing but metabolically active bacterial cells.
- To address the limitations of traditional culture-based methods for analyzing non-replicating cells.
- To explore the physiology of bacterial cells that are metabolically active but not replicating.
Main Methods:
- Real-time single-cell analysis.
- Combination of fluorescent reporter dyes and strains.
- Microfluidic and microelectromechanical systems (MEMS).
- Time-lapse fluorescence microscopy.
Main Results:
- The study proposes that novel technologies can overcome limitations of traditional methods.
- Real-time analysis allows for direct observation of non-replicating cells.
- The combination of methods offers significant potential for future research.
Conclusions:
- Advancements in single-cell analysis technologies are crucial for understanding bacterial physiology.
- These methods provide new avenues for studying the "non-growing but metabolically active" state.
- Future research can leverage these tools to investigate bacterial persistence and resuscitation.
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