In view of existing as well as potential future uranium pollution, the current complicated, time-consuming, inefficient and expensive treatment methods seem woefully out-of-date. To address these drawbacks, the Peking iGEM team put forward the Uranyl Reaper project, which aims to develop an innovative method to deal with uranium pollution.
In order to achieve this goal, we designed an extraordinary biological adsorption material which is produced by engineered bacteria and self-assembles completely autonomously. Based on the isopeptide bond formed between SpyCatcher and SpyTag, two designed crosslinking peptides, we developed trimeric SpyTag and SpyCatcher modules which can form a covalently-linked network which offers high mechanical strength and high stability in diverse challenging environments.
This network further gains a capacity to adsorb uranium in aqueous environments with high efficiency via the addition of a super uranyl binding protein (SUP) module. The SUP could also be replaced with other functional elements such as additional metal binding proteins, or the monomerized streptavidin (mSA) module which can mediate the recovery of the self-assembled network through biotin-avidin interactions, in order to achieve multi-functionality and modularization.
We utilized a series of signal peptides to ensure efficient secretion. A schematic graph of the whole project is shown in Figure 1.
Figure 1. Schematic diagram of the Uranium Reaper project.
