Team:USTC/Description

Inspiration

Dressed in colorful clothes, we began to wonder where the color came from. After some browsing and consulting, we found out among all kinds of dyes, azo dyes are the most widely used ones. Azo dyes are a kind of chemicals that are especially hard to tackle. Owing to its high stability, convenient approaches to degrading them are either too expensive or not efficient enough. As a consequence, these deleterious chemicals often remain in water, causing continuous harm to the environment as well as living creatures including human beings, so we are trying to address this problem synbiologically.

Description

The most straightforward method is to introduce a degradation system into the bacteria. Luckily, there is a species of bacteria (Shewanella oneidensis MR-1) with the ability to generate electrons. We harnessed and improved that. Still poorly informed on the real situation of azo dyes treatment, we paid a visit to a dyeing house and got firsthand information, as azo dyes are mainly used in dyeing industry. Shortly afterwards, another visit to a waste water plant was paid. Deriving from the information, we concluded that existing microbial treatment is inefficient mostly due to the toxicity of aromatic amines. Solving it required a resistance system that can keep the bacteria active for a longer period. Our aromatic amines resistance system emerged. Based on the devices in waste water plant, we chose a light-activated kill-switch to ensure security. An additive part was designed to lower the cost of cultivating bacteria.

We believe that with the engineered S. oneidensis MR-1, the treatment of azo dyes will be easier and more effective, producing cleaner water finally.