Difference between revisions of "Team:Aix-Marseille/Description"
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<p>An alternative weaponry must be found to replace the harmful and expensive traditional insecticides, that is now nearly useless against bed bugs. Because of the excessive use of insecticides, the tiny bugs developed multiple resistance mechanisms (exoskeleton thickening and enhanced metabolic pathways to neutralize toxic chemicals such as chlorpyrifos). As a result, pest control companies are obliged to increase the insecticides' doses with high risks of toxicity incurred for mammals, birds, aquatic animals, and bees. | <p>An alternative weaponry must be found to replace the harmful and expensive traditional insecticides, that is now nearly useless against bed bugs. Because of the excessive use of insecticides, the tiny bugs developed multiple resistance mechanisms (exoskeleton thickening and enhanced metabolic pathways to neutralize toxic chemicals such as chlorpyrifos). As a result, pest control companies are obliged to increase the insecticides' doses with high risks of toxicity incurred for mammals, birds, aquatic animals, and bees. | ||
| − | <h3>The | + | <h3>The solution : A two-subunits lethal trap</h3><br> |
<h4>First subunit</h4> | <h4>First subunit</h4> | ||
Revision as of 20:30, 9 October 2018
Description
Description
Our focus this year is fighting bed bugs, worldwide invasive pests, that are invading homes and biting humans for their blood. These tiny bugs became harmful from the moment humans made caves their homes, as the original hosts of bed bugs were bats. Nowadays humans don’t live in caves, but this temporary troglodyte dwelling came with a cost: fighting against an insect addicted to human blood. While their bite usually doesn’t transmit any disease, it still induces serious dermatological and allergy issues.
The breaking bugs project aims to provide a human-friendly, and efficient solution to eliminate bed bugs. The plan is to elaborate an attractive lethal trap. We will use biosynthesized pheromones as a chemical lure to attract the bugs into the trap and infect them with Beauveria bassiana (an entomopathogenic fungus), causing a fatal epidemic among the sheltered colonies.
The problem ?
An alternative weaponry must be found to replace the harmful and expensive traditional insecticides, that is now nearly useless against bed bugs. Because of the excessive use of insecticides, the tiny bugs developed multiple resistance mechanisms (exoskeleton thickening and enhanced metabolic pathways to neutralize toxic chemicals such as chlorpyrifos). As a result, pest control companies are obliged to increase the insecticides' doses with high risks of toxicity incurred for mammals, birds, aquatic animals, and bees.
The solution : A two-subunits lethal trap
First subunit
To elaborate our trap, we are going to use the biological properties of an entomopathogenic fungus called Beauveria bassiana.
It was first used as a way to fight against insects in agriculture in Canada, and later on, all over the world. The fungus can penetrate the bed bug's exoskeleton: the cuticle. Firstly, the spore attaches to the cuticle and germs. Secondly, the spore breaks down a first fatty acids layer using the lipase protein. The fungus keeps going and breaks the second layer: the chitin, using the endochitinase protein. Afterward, it reaches the insect's hemolymph, then feeds, multiplies, and releases toxins, causing the bed bug's death. The whole process takes about 12 days. Our objective is to enhance the fungus to improve its killing efficiency and speed by overexpressing the lipase and endochitinase proteins and adding other adjuvants. We want to reduce the lethal doses and kill the bed bugs in fewer days.
Second subunit
Pheromones are chemical substances that are usually produced by bed bugs. They serve as a stimulus to navigate in space and make a path between their preys and their shelters. The plan is to disrupt this path and create a diversion using two types of pheromones that can be found in the bed bugs' feces and exuviae: benzyl alcohol and DMDS/DMTS. Firstly, we are going to add the respective biosynthesis pathways in E. coli, and extract the produced pheromones in a further step. This procedure enables low-cost production using simple commodities (Sugar...).