Bioluminescent biosensor device

A method of detecting a selected target bacterium, comprising:

• providing a genetically engineered bacterial bioluminescent bioreporter cell population responsive to an inducer;
• providing a modified bacteriophage capable of specifically infecting said target bacterium but not the biorporter cells, said bacteriophage being genetically modified to cause the target bacterium to express said inducer upon infection of the target bacterium, and
• contacting a sample suspected of containing said target bacterium with said bacteriophage together with a population of said bioreporter bacterial cells,
• wherein a detectable bioluminescent signal is induced in said cell population subsequent to infection of the target bacterium with the bacteriophage, said detectable bioluminescent signal being correlated the presence of the target bacterium.

A method of determining the amount of a selected bacterium in a sample comprising:

• contacting a sample suspected of containing a selected bacterium with:
• (a) a bacterium-specific bacteriophage genetically modified to cause the bacterium to express an inducer upon infection of the bacterium;
• and
• (b) a population of bacterial bioreporter cells responsive to the inducer;
• wherein the amount of the selected bacterium is determined by measuring the time required for production of a selected intensity of bioluminescent signal by the bioreporter cell population in the presence and in the absence of the selected bacterium;
• and relating the amount of said selected bacterium to the difference in time required for production of the selected intensity of bioluminescent signal by the bioreporter cell population in the presence and in the absence of the bacterium.

A kit for detection of selected bacteria, comprising in suitable container form:

• (a) a genetically engineered bacteriophage that harbors a luxI gene and specifically infects a selected bacterium;
• (b) a bioreporter cell population genetically engineered to include a luxR-luxpro/luxI/luxCDABE gene construct, said bioreporter being incapable of infection by said bacteriophage;
• and
• (c) instructions for use.

A kit for detection of a target bacterial cell comprising in suitable package form:

• (a) a genetically engineered bacteriophage that harbors a luxI gene and specifically infects a selected bacterium;
• (b) a bioreporter cell population genetically engineered to include a luxR-luxpro/luxI/luxCDABE gene construct, said bioreporter being incapable of infection by said bacteriophage;
• and
• (c) a device for measurement of generated light, said device comprising at least one container suitable for housing the bioreporter cell population, target cell population and bacteriophage, said container being operably connected to an integrated circuit adapted for detecting a luminescent signal produced when a bacteriophage-infected target cell induces a bioluminescent protein in the bioreporter cell population;
• and
• (d) instructions for use.

A biosensor/bioreporter device for detecting a bacterial target cell population comprising:

• (a) a bacterial bioluminescent bioreporter cell population responsive to an acyl-homoserine lactone inducer, said bioreporter containing a luxR-luxpro/luxI/luxCDABE gene construct;
• (b) at least one bacteriophage capable of specifically infecting the bacterial target cell but not the bioreporter cell, said bacteriophage being genetically modified to cause the target cell to express said acyl-homoserine lactone inducer upon infection of the target cell;
• and
• (c) at least one container suitable for housing the bioreporter cell population, target cell population and bacteriophage, said container being operably connected to an integrated circuit adapted to detect a bioluminescent signal generated in said container upon interaction of the bioreporter cell population and the inducer, wherein detecting the bioluminescent signal is correlated with detecting the presence of the target cell.