We tend to believe -- and quite rightly so -- that germs are a detriment to our economy. The billions of dollars spent each year to treat infections can overburden the budget of any healthcare institution and the pocketbooks of anyone without appropriate health insurance.
But pathogens only make up a fraction of the diversity of germs on Earth and a number of environmental germs have been examined for their financial and environmental benefit. For the most part, these germs are unknown, kept away from the science spotlight, and gaining little to no appreciation for the work that they do.
That changed last week when the laboratory of Dr. Nathan Magarvey at McMaster University in Hamilton found that a particular bacterium known as Delftia acidovorans (meaning acid devouring bacteria from the city of Delft in Holland where it was discovered) not only could be found growing in gold deposits, but was actually mining the gold and using it as a place to reside.
In essence, the bacteria were creating a house made of gold. Magarvey also showed that the accumulation of gold was performed by a single molecule, delftibactin, which could one day be mass produced. Should this happen, these bacteria may improve the efficiency of gold mining and more importantly, increase the range of places where mining can be performed, including the oceans.
The concept of microbial mining, also known as bioleaching, may only now be making headlines; yet the process has been ongoing for decades.
Some four decades ago, a group out of the University of Southern California found that a group of bacteria known as the thiobacilli (meaning sulfur loving bacteria) could be used to break down the complex nature of oil shale to liberate the oily residue easing both collection and processing. Their work, while gaining little public attention, led to a number of other groups investigating how bacteria could be used to increase mining profit margins.
One major success has come in the copper mining industry. In this case, the bacterium, Acidithiobacillus ferrooxidans (meaning a bacterium that uses sulfur to make an acid that oxidizes iron) was found in the slag of copper mines and appeared to help release copper from rock.
Initially, the bacteria were used to help recover copper from discarded circuit boards however there was simply no denying the benefit of upscaling bacterial production to general mining operations. The bacteria were quickly adopted and their use spread worldwide. Today, bacterial bioleaching is involved in some 10 per cent of the world's copper production.
While bacterial assisted production of commodities is easily recognized as a help to our economy, there is another way bacteria help us to maintain lower costs although in this case, the target isn't money, it's the environment. Germs are nature's degraders and over the last half-century, a number of species have been found to not only enjoy biological material, but also man-made chemicals including pesticides, plastics, and toxins such as mercury.
But perhaps the most important revelation came exactly 40 years ago when a group out of the University of Alberta in Edmonton found that bacteria could degrade crude oil. The discovery sparked an era of research into how bacteria could be used to clean up oil spills and other less publically favourable consequences of oil drilling.
Most of the work was done quietly with private funding but that all changed in 1989 with the Exxon Valdez spill in Prince William Sound, Alaska. The spill was so dramatic that it led to news headlines worldwide and sparked condemnation of the entire oil industry. There was no choice to investigate bioremediation.
The efforts were so successful that the bacteria were eating up as much as 1 per cent of the spillper day. After the Exxon Valdez, germs were used to help re-mediate spills from the Russian tanker Nakhodka and the most recent Deepwater Horizon disaster in the Gulf of Mexico. The use of germs has become so popular that no oil environmental management system is complete without some reference to bioremediation to keep costs down and success rates high.
In the future, germs will play an even greater role in our economy and not solely in the role of villain. Thanks to decades of research by basic microbiologists who rarely are garnered public attention, the financial benefits of bacteria and fungi will be maximized to help enrich our commodity supplies and help keep the environment clean.
The results won't be seen for some time but we can expect that our vacations will be safer from the threat of environmental contamination and perhaps more close to home, the cost for that golden Valentine's Day gift for your sweetheart might actually be affordable.