Cry for Mosquitoes: A New Way to Control Mosquitoes by Synthesis Biology

1.Introduction:

          Mosquitoes are one the most harmful insects in the world because they bite animals and human and spread virus. How to control mosquitoes in an efficient, green and cheap way has been a worldwide problem. This year, FAFU-CHINA iGEM team decide to start with the food source to control the amount of mosquitoes.

          According to the preliminary researches about the physiological characters of mosquitoes larvaes.  They feed on algae, plankton, fungi and bacteria and other microorganisms. Bacillus thuringiensis (Bt.) is a Gram-positive bacterium which commonly used as biological pesticide. Based on the previous research in Fujian Agriculture and Forestry University, LLP29 is a bacterial Bt. which isolated from the natural environment in Mountain Wuyi. LLP29 has been proved the specific and efficient toxicity to Mosquitoes larvaes by bioassay. But the Bt. own the fatal weakness that they cannot live for a long time in the natural environment, especially when they are under sunshine exposure. The heterologous expression of toxins in the suitable organism will be a good choice to solve this problem. Saccharomyces cerevisiae is a generally choice for heterologous expression in the eukaryote. But to decrease the cost of this method, we decide to make use of photosynthetic organism which can live in water. Chlamydomonas reinhardtii is a single-cell alga which belongs to the Chlorophyte Phylum. It can be the food source for mosquitoes larvaes.  According to the result of identification and clone from LLP29, Cry and Cyt proteins are the main resource of toxicity. According to the previous research, Cry proteins can improve the toxicity of Cyt proteins by combination. Therefore, we chose 2A-peptide expression system to co-express Cry and Cyt proteins.