For practical projects, especially involving synthetic biology, safety should be attached great importance to. This year, we designed an electricity generation device based on microbial co-culture. In terms of experimental design, experimental operation and so on, we fully considered their safety and implement safety at every step.
1. Safe Project Design
Safe strains and safe gene products were selected to complete our project design. The products of the genes transferred into the microorganisms are all determined and do not cause any known diseases to human, animals and plants. Any microorganisms involved in our project is encapsulate in electricity generation device. So far, the devise can recharge the phone, and in the future, electricity generation based on microbial co-culture may become a new choice of electricity production.
In our project, Synechocystis are used as a control strain to compare the electricity production efficiency of Shewanella when Synechocystis and Rhodopseudomonas palustris are respectively co-cultured with Shewanella. The Synechocystis selected is Synechocystis sp. PCC6803, which is widely used in algae research as a model organism. Because of its long growth cycle, strict growth conditions, and special culture medium, we can control its growth in many ways to avoid pollution.
Rhodopseudomonas palustris(DSM5859) is one of the protagonists in our project. It is responsible for converting optical energy into chemical energy with lactic acid producing and secreting lactic acid for the electricity production of Shewanella. Rhodopseudomonas palustris is commonly used in sewage treatment. It is a kind of microorganism being harmless to the human body and environmentally friendly.
Shewanella is the key species for optical energy conversion, which can consume lactate and reduce metal to produce electricity. The Shewanella oneidensis MR-1 we used can be used for wastewater treatment . For the time being, there is no report of diseases with it.
2. Safe Lab Work
Our team also pay special attention to safety issues during the experimental operation. New members are required to undergo experimental training from Principle Investigators, graduate students and previous team members in our lab before conducting experiments. Experimental training includes standard experiment operations, safety regulations of equipment usage and good practice rules in the polluted area. In addition, undergraduates have to use secondary equipment with company of a graduate student. In our project, microbial co-culture used to generate electricity must be sterilized at 121 ℃ for 25 minutes before disposal. Based on previous experience, we highlight the following points in experimental safety:
1.Polluted area must be isolated from the nomal bench. Experimenters are required to wear lab coat and polyvinyl chloride plastic gloves before entering.
2.Toxic reagents must be collected specially.
3.Volatile chemicals involved experiment must be operated in the fuming cupboard.
4.Laboratory appliance must be sterilized before and after use.
5.Maintaing of complex equipment must be in the charge of staff.
3. Safe Shipment
Safety is also important when sending parts to the registry. All materials sent must be frozen dried and the sealed 96-well plate must wrapped with enough bubble paper to prevent breaking. Sometimes the DNA delivery will be checked by customs, so we have prepared safety certification to ensure that the materials are harmless. Packaging and delivery are done in accordance with the requirements of the courier company and iGEM HQ.
 Xiang Xiao, Xiao-Bo Ma, Hang Yuan. Peng-Cheng Liu, Yu-Bin Kei, Hui Xu, Dao-Lin Du, Jian-Fan Sun, Yu-Jie Feng. Photocatalytic properties of zinc sulfide nanocrystals biofabricated by metal-reducing bacterium Shewanella oneidensis MR-1. Journal of Hazardous Materials. 2015, 288: 134~139.