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Updated: Aug 13, 2026

In Situ Measurement and Correlation of Cell Density and Light Emission of Bioluminescent Bacteria
Published on: June 28, 2018
Influence of intracellular pH on light emission from a luxA/B derivative of Lactococcus lactis subsp. diacetylactis
1BRF International, Nutfield, Surrey, UK.
Abstract:
High levels of constitutive aldehyde-dependent light emission were obtained from nongrowing cells of Lactococcus lactis subsp. diacetylactis F712 transformed with IuxA/B when they were suspended in buffered solutions. Inductions of light emission was time-dependent and was not due to growth, synthesis of luciferase or stimulation of metabolism by fermentable carbohydrate. The major factor controlling light emission in such cells appears to be the intracellular pH value. Experiments with ionophores indicated that a transmembrane pH gradient was not essential for light emission.
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