Synthetic biologists have created a prototype for a groundbreaking biosensor that can identify rare earth elements and be adapted for various other uses.
Researchers at QUT have designed a prototype for a cutting-edge biosensor capable of detecting rare earth elements and adaptable for numerous applications.
Lanthanides (Lns) are critical components in electronics, electric motors, and batteries. However, the challenge lies in our inability to extract enough of these elements to satisfy the increasing demand, along with the fact that current extraction methods are both costly and harmful to the environment.
Professor Kirill Alexandrov and his team from the QUT Centre of Agriculture and Bioeconomy and the ARC Centre of Excellence in Synthetic Biology engineered proteins to create molecular nanomachines that produce easily detectable signals when they selectively attach to Lns.
Alongside Professor Alexandrov, the international research team included QUT researchers Dr Zhong Guo, Patricia Walden, and Dr Zhenling Cui, collaborating with researchers from CSIRO Advanced Engineering Biology Future Science Platform and Clarkson University in the USA.
In their publication in Angewandte Chemie International, the team discussed how they created a hybrid protein, known as a “chimera,” by fusing a lanthanide-binding protein, LanM, with an enzyme that breaks down antibiotics called beta-lactamase.
This hybrid functions as a “switch” that activates only in the presence of lanthanides, enabling the detection and quantification of Lns in liquids, which results in a visible color change or an electrical signal.
Remarkably, bacteria altered with these chimeras managed to survive in the presence of antibiotics that would typically be lethal, but only when lanthanides were present. This demonstrates the precise responsiveness of these proteins to rare metals.
“This research opens up thrilling opportunities for using biological methods to identify and recover rare earth metals,” noted Professor Alexandrov.
“The prototype is also customizable for various biotechnological uses, such as creating living organisms capable of detecting and extracting valuable metals.”
The research team intends to enhance the specificity of the molecular switch to better distinguish between closely related rare earth elements. They are also looking into developing switches for other essential elements and actively discussing collaboration with potential industry partners interested in this technology.
“We are also considering using this tool to engineer microbes that can directly extract rare earth minerals from seawater,” added Professor Alexandrov.
“This is among the most effective switches we have developed, providing us with valuable insights into the functionality of protein switches.”
