The Wild Wild World Of Bacteria Unleashed

The Wild Wild World Of Bacteria Unleashed Image
Bacteria were here long before we were. They can occupy a wider range of environmental niches than humans -- from deep sea hydrothermal vents to the thin cold upper atmosphere. Bacterial spores can even survive an extended transit through the cold vacuum of outer space. They live throughout the inside and the outside of our bodies. We are learning to program some bacteria to produce fuels, medicines, chemicals, foods.... They can make life easier for us -- or they can make it harder. It is our choice.Lovley's microbial electrosynthesis converts solar power directly into chemicals, which are then readily stored with existing infrastructure and distributed on demand, and are 90 percent efficient at turning electrons into fuel without further processing.

Lovley and colleagues published their experimental results and discuss implications in the current, May issue of mBIO, an online journal of the American Society of Microbiology, and are presenting this week at the American Society for Microbiology's annual meeting in San Diego, which runs from May 23-27.

The bench-scale technology, funded by a 1 million DOE grant, is based on the discovery that some bacteria can feed on electrons delivered by electrodes. These microbes live on the electrodes and use electrons released from them as their food source. "This is basically a new form of photosynthesis, in which carbon dioxide and water are combined to produce organic compounds, and oxygen is released as a byproduct," Lovley explains. Solar energy powers the microbes to "breathe in" carbon dioxide and "exhale" fuels and chemicals. The main product is acetate or acetyl-Co A, from which many fuels and other chemicals can be easily produced, notably butanol.

Researchers at the US Department of Energy's Oak Ridge National Laboratory have identified a key gene in the bacterium Zymomomas mobilis-an anaerobic ethanologen-that, when overexpressed in a new Z. mobilis strain, delivers increased tolerance to acetic acid, a common inhibitor produced in biomass pretreatment. Increased tolerance can yield more cost-competitive cellulosic ethanol. An open access paper on their work was published online 19 May in the Proceedings of the National Academy of Sciences.

...Currently, biomass materials like corn stover and switchgrass must undergo a series of pretreatments to loosen the cellular structure enough to extract the sugar from cellulose. Steven Brown, staff microbiologist in the Biosciences Division and one of the inventors of the improved Z. mobilis strain, said these treatments add new challenges because, although they are necessary, they create a range of inhibitors that stall or stop microorganisms like Z. mobilis from performing the fermentation.

There are two ways to combat recalcitrance, or the difficulty created by the inhibitors. One way is to remove the inhibitors, but this method is very expensive and would not help biofuels become cost-competitive with gasoline. The second way is what we do, which is to develop microorganisms that are more tolerant of the inhibitors.

Now we are learning that some bacteria may even help us learn and think better:

Studies have shown time spent in nature does us all good. Specifically a recent study done with 1,200 people, published in the journal Environmental Health and Technology found that even just five minutes in a leafy park can significantly boost our mood. Well it might be because we inhaled some bacteria among the leaves and grass.

It's called mycobacterium vaccae and research presented today at the 110th General Meeting of the American Society for Microbiology found that it might also increase an ability to learn.

Bacteria can be tweaked to better help clean up the environment.

Some bacteria may help to affect the weather.

Bacteria love to munch on oil -- which is why oil spills do not leave permanent traces.

Normal bacteria in our foods can help us digest food better, and provide us with vitamins and nutrients that our body cannot produce for themselves.

Now that we are tweaking so many different kinds of bacteria to do our work for us, we had better know how to control strains of bacteria that may try to run out of control.

It is not desirable to try to eliminate all bacteria from our environment. We have co-evolved with bacteria for millions of years. We need them. And as we are learning to control them to make more of the products we need and desire, we should always keep in mind that they were here first. They have had a lot of time to develop nasty surprises for high-flying monkeys wearing suits.

Credit: [Steven Brown]
Source: [Biofuels Digest]