Scientists from McMaster University said that they have identified which genes are responsible for the processes of gold production. They isolated delftibactin for the first time.
There are very few gold ions in water of any kind and type, which theoretically can be removed and assembled from them into an ingot. Now this has been confirmed in practice. A bacterium named Delftia acidovorans, studied by Canadian microbiologists, uses a substance called delftibactin to cause gold to precipitate out of solution. Thus, bacteria create safe living conditions for themselves (their cells are no longer threatened by ions).
Gold ions are found both in tap water and in sea and sewer water, in various wastes. With the help of the bacteria Delftia acidovorans, all this water can be purified and gold can be obtained. The substance that bacteria create also removes iron ions from the water, so at the exit you can get iron nuggets with a gold impurity, and then separate them.
Unfortunately, this technology is too expensive and gold cannot be produced on a mass scale.