The Arctic is definitely an incredible place. Today in our Microbial Advent Calendar we look at amazing Microbial factories. In a 2016 paper (here) Plaza et al., identified several gammaproteobacterial strains capable of synthesizing fluorescent nanoparticles or quantum dots. Quantum dots are nanoparticles that are their own central theme in nanotechnology. They emit light of specific frequencies if electricity or light is applied to them, and these frequencies can be precisely tuned by changing the dots’ size, shape and material, giving rise to many applications. Those include transistors, solar cells, LEDs, diode lasers and second-harmonic generation, quantum computing, medical imaging and even inkjet printing!
In biology in particular small colourful and very bright molecules are of considerable interest, particularly for imaging techniques. Quantum dots are smaller than traditional fluorophor reporters, 20 to 100 time brighter and less sensitive to photobleaching. They could also be used in vivo, for example, for medical diagnostics by using probes targeting tumorous cells.
In the paper from Plaza et al., they demonstrate that some free-living Gammaproteobacteria from the artic developed heavy metal resistance using Quantum dot particles. In presence of Cadmium and Tellurite, the bacteria produce the nanoparticle which precipitates the metal molecule. They showed that in presence of heavy metal the quantum dot colour changes from red to green with time.
This bacteria a real micro-factories of quantum dots and could a green way to produce valuable nanoparticles in the future.