Ultrasensitive reporter protein detection in genetically engineered bacteria

Area of Science:

• Biotechnology
• Spectroscopy
• Microbiology

Background:

• Genetically modified Escherichia coli are widely used as bioreporters.
• Monitoring bioreporter responses is crucial for detecting environmental contaminants and biological processes.
• Existing methods often lack the sensitivity to detect responses at the single-cell level.

Purpose of the Study:

• To demonstrate a novel application of laser-induced fluorescence confocal spectroscopy for measuring bioreporter activity.
• To establish a method for quantifying enhanced green fluorescent protein (egfp) synthesis in individual live bacteria.
• To showcase the potential of single-molecule detection instrumentation in bioreporter assays.

Main Methods:

• Utilized laser-induced fluorescence confocal spectroscopy.
• Employed genetically modified Escherichia coli bioreporter cells.
• Measured egfp synthesis in both cell lysates and individual live bacteria.
• Leveraged single-molecule detection capabilities.

Main Results:

• Successfully measured analyte-stimulated egfp synthesis in Escherichia coli.
• Demonstrated the ability to monitor bioreporter response at the single-cell level.
• Achieved proof-of-concept for a new spectroscopic method for bioreporter analysis.

Conclusions:

• Laser-induced fluorescence confocal spectroscopy is a viable method for quantifying bioreporter responses.
• The technique enables sensitive detection of egfp synthesis in individual live bacteria.
• This approach is extensible to various egfp/gfp bioreporters and analytes beyond arsenic.