Nature:
Gold that is dissolved in solution is toxic to many species of
bacteria. However, two species have been found that convert the
dissolved gold into inert nanoparticles. One of the bacteria
species creates the nanoparticles internally, while the other,
Delftia acidovarans, deposits them externally. A team of
researchers led by Nathan Magarvey of McMaster University in
Hamilton, Canada, has determined the set of genes and the
chemical metabolite responsible. The researchers engineered the
bacteria to remove the genes they thought were involved and
found that the bacteria's growth was significantly stunted.
They believe the genes were responsible for creating a
chemicalâmdash;which they dubbed
delftibactinâmdash;that caused the gold to
precipitate out of solution and for pushing the gold out of the
cell. Magarvey says there may be other mechanisms involved as
well. The researchers believe that delftibactin or the bacteria
themselves could be used to produce gold nanoparticles
industrially or to precipitate gold out of wastewater from
mines.
