Heavy metals (Cu2+, Cd2+, etc.) influence every aspect of human life. Although they are important to chemical, medical, and manufacturing industry, exposure to them has caused lots of hazards to humans.
With the rapid development of global industrialization, heavy metal pollution has become a severe problem threatening everyone's health. Thanks to the global collaboration with more than 20 teams involved in, our principals of human practice and model have completed a world map for some heavy metals' pollution. The result illustrates a serious situation we are faced with.
The pollution of cadmium worldwide
After actual investigations with government, companies, and NGOs, three key questions have been summed up. How can microorganism survives in an environment with a relatively high concentration of heavy metals? How can we separate different metals with fewer reactions? How can we monitor the water quality after treatment in real time?
For these questions, we chose to use a brand-new strategy, synthetic life, to answer them. Within the framework of Sc2.0 project, scientists from all over the world work together to build the world's first synthetic eukaryotic genome - Saccharomyces cerevisiae's genome. Chinese team from Tianjin University has completed two synthetic chromosomes and we are very lucky to use the synthetic yeast to solve these questions.
We used a particular genome evolution system, SCRaMbLE (Synthetic Chromosome Recombination and Modification by LoxP-mediated Evolution), to rapidly obtain the budding yeast with the tolerance of high concentration of heavy metals. To answer the second question, we also boldly and creatively designed an orthogonal switcher with the SCRaMbLE system, based on the change of yeast's mating type which determines the sex. We also improved and created many parts to build a biosensor for copper ions with higher sensitivity and wider response range.