We are not the first team to focus on DNAzyme. Before us, several iGEM teams have used DNAzyme in their projects. Among these teams, the concept of "Hot Metal Switch" by the Pittsburgh team in 2016 is very similar to our project. They used DNAzyme 8-17 as a heavy metal ion detector. But our project is also different from theirs: we have conducted a specific and in-depth study of the 8-17DNAzyme used, and contributed a new part to iGEM. We will once again introduce the contribution of this project in DNAzyme.

8-17 DNAzyme

We used 8-17 DNAzyme in the project, and realized the detection of heavy metal ions by its ability to bind heavy metal ions and cut DNA single strands. The experimental results are as follows:

Fig 7.1.1 DNAzyme Pb2+ concentration testing.

Through our testings, we proved 8-17 DNAzyme's high efficiency and determined that 8-17 DNAzyme's detection limit for Pb2+ is 0.01 μM.

8-17 Mutation test

During our experiments on 8-17 DNAzyme, we conducted mutation tests in order to acquire a 8-17 DNAzyme mutant that has higher activity. The experimental results are as follows:

Fig 7.1.2 further testings for 14 potential 8-17 DNAzyme mutants. (the control group = 8-17 DNAzyme mut 0 without Pb2+)

We tested 14 potential 8-17 DNAzyme mutants which possess approximately same activity as the original 8-17 DNAzyme. By comparing the 14 mutants, we discovered the most effective mutant--mut 10. The testing was repeated five times.


Through our experiments on 8-17 DNAzyme, we proved its efficiency in Pb2+ detection and determined its detection limit. The data we gathered lays a solid foundation for future iGEM teams.

We also discovered a 8-17 DNAzyme mutant (mut 10) that possesses higher activity than the original 8-17 DNAzyme. The efficiency of this mutant will contribute to further research in this field.