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Updated: Jun 19, 2026
05:52
In Situ Measurement and Correlation of Cell Density and Light Emission of Bioluminescent Bacteria
Published on: June 28, 2018
THE TOTAL LUMINOUS EFFICIENCY OF LUMINOUS BACTERIA
1Nela Research Laboratories, Cleveland, and the Physiological Laboratory, Princeton University, Princeton.
The Journal of General Physiology
|October 30, 2009
Summary
Researchers measured light output and oxygen consumption in luminous bacteria to determine their energy efficiency. These bacteria convert chemical energy into light with remarkable efficiency, comparable to artificial light sources.
Area of Science:
- Biochemistry
- Microbiology
- Photophysics
Background:
- Bioluminescence in bacteria is a fascinating natural phenomenon.
- Understanding the energy conversion efficiency of bioluminescent organisms is crucial for various applications.
- Quantifying light emission and oxygen consumption provides insights into metabolic pathways.
Purpose of the Study:
- To measure the light emitted by luminous bacteria and their oxygen consumption.
- To calculate the efficiency of light production by individual bacteria.
- To compare bacterial luminescence efficiency with artificial light sources.
Main Methods:
- Measuring light output from bacterial emulsions of known thickness.
- Calculating light emitted per bacterium, accounting for potential light absorption.
- Measuring oxygen consumed by bacteria to determine their metabolic rate.
- Determining bacterial concentration and individual cell volume for accurate calculations.
Main Results:
- Maximum light emission per bacterium was determined (24 x 10^-14 lumens).
- Luminescence intensity remained stable until oxygen concentration dropped below 2%.
- Calculated overall luminescence efficiency of bacteria (0.0078 or 5 lumens/watt) and a luminescence efficiency of 26.2% (168 lumens/watt).
Conclusions:
- Luminous bacteria exhibit significant efficiency in converting chemical energy to light.
- Bacterial luminescence efficiency is comparable to, and potentially exceeds, that of some artificial illuminants.
- Potassium cyanide (KCN) partially separates respiratory and luminescence-related oxygen consumption.
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