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Team:NYMU-Taipei/Safety
Contents |
Introduction
Our Bee. coli expresses some antimicrobial peptides such as defensin and abaecin to fight against Nosema cerenae. There is probability that Bee. coli contaminates the natural environment and cause death to other species. Therefore, light-induced lysis system was created to ensure our Bee. coli only lives inside of the bee.
Background
Blue Light Sensing Device
We chose to use [http://parts.igem.org/Part:BBa_K592016 K592016] as our light sensing device. [http://parts.igem.org/Part:BBa_K592016 K592016] consists two parts: YF1 and FixJ. YF1 IS a blue-light sensor protein. It works in conjunction with its response regulator, FixJ. When exposed to blue-light, they can activate [http://parts.igem.org/Part:BBa_K592006 K592006], the blue-light sensing promoter.
Lysis Device
The lysis device is composed of promoter [http://parts.igem.org/Part:BBa_K592006 K592006], the blue-light sensing promoter, and the lysis protein K896999, which is a lethal 91 amino acid membrane protein that induces lysis in E. coli.
Circuit design and Experimental Method
Circuit Device
[http://parts.igem.org/Part:BBa_K592016 K592016] is cloned after constitutive promoter J23102, so the proteins YF1 and FixJ were continuing produced. When exposed to blue light, the inactive YF1 and FixJ will be change to their active form and induce the downstream gene of promoter [http://parts.igem.org/Part:BBa_K592006 K592006]. In our circuit, the lysis protein K896999 will be produced and kill our Bee. coli which escaped from the midgut of a bee.
Experimental Method
First, we substitute lysis protein K896999 with green fluorescent protein E0040. By this way, we can test the efficiency of the circuit.
Next, by comparing the number of colonies of the plate that is exposed to light and the plate that is blocked from light after 16 hours of in incubator, we can characterize the function of our device.
Left: Plate is exposed to light.
