Densign
In order to solve locust plague, we want to design a degradation enzyme system to degrade guaiacol and serotonin, because these two pheromone would cause the locust aggregation. Therefore, we constructed two plasmids PSHS4 and PSHS5 which contain enzymes that can degrade guaiacol and serotonin. We transferred these two plasmids into E. coli separately and then transferred the E. coli to the locust gut. So, we can reduce the concentration of aggregation pheromones inside the locust intestines and prevent locusts from clustering by the bacteria we constructed.
Moreover, we expect our system can express the proteins which can degrade pheromone efficiently, so we used a synchronous lysis circuit (SLC). When bacteria reach a certain number in the intestine of locusts, the bacteria will automatically lyse and release enzymes to degrade guaiacol and serotonin.
After the bacteria are lysed, a small part of the bacteria will survive and grow up to enter the next lysis. This process can release a large number of protein at the same time, and degrade the pheromones fully and efficiently.
And then, to ensure biosafety, we designed a heat-responsive suicide switch so that in summer, when the locust plague decreases, the bacteria in the locust’s intestines will commit suicide to prevent biological leakage.
