Sludge power

April 18, 2000

Keep your spaceship in running order with a sewage cocktail

Astronauts may one day be able to use their spacecraft's septic tank to keep in touch with ground control -- as long as they have plenty of sugar. Scientists in Michigan have developed a biofuel cell that creates a constant, low-power electricity supply by feeding glucose to common bacteria such as E. coli.

Biochemists Gregory Zeikus and Doo Hyun Park at Michigan State University in East Lansing have manipulated the bugs' metabolism to convert them into tiny powerhouses. They have built a 0.6 volt biofuel cell that can deliver currents of up to 17 milliamperes.

Bacteria normally break down glucose to generate adenosine triphosphate -- the main energy source for cells. This involves a flow of electrons, which the researchers have tapped into by adding a chemical called neutral red. Molecules of neutral red insert themselves into the bacterial membrane, where they hijack the reaction's electron-transport process, and shuttle electrons onto an electrode.

"It's like an electric plug," says Zeikus. "You put it in the cell membrane and put the cells in a cathode to make electricity." The method isn't likely to be powering your CD player any time soon, but Zeikus says it could be used as a backup method of maintaining communications in remote areas such as space. There is a bonus, too. Because some of the bacteria's energy is diverted to producing electricity, they don't multiply as fast as usual, leaving less sludge to dispose of.

Ziekus and Park are not the only researchers exploring the electrical potential of sugar-fed biofuel cells. Itamar Willner and his colleagues in the chemistry department of the Hebrew University of Jerusalem in Israel, for example, are using enzymes rather than bacteria to make batteries that could be implanted in people's bodies. Powered by blood sugar, the batteries could one day power pacemakers, insulin pumps and prostheses.
-end-
Author: Nicole Johnston

Source: Applied and Environmental Microbiology (vol 66, p 1292)

New Scientist issue: 22nd April 2000

PLEASE MENTION NEW SCIENTIST AS THE SOURCE OF THIS STORY AND, IF PUBLISHING ONLINE, PLEASE CARRY A HYPERLINK TO: http://www.newscientist.com

New Scientist

Related Bacteria Articles from Brightsurf:

Siblings can also differ from one another in bacteria
A research team from the University of Tübingen and the German Center for Infection Research (DZIF) is investigating how pathogens influence the immune response of their host with genetic variation.

How bacteria fertilize soya
Soya and clover have their very own fertiliser factories in their roots, where bacteria manufacture ammonium, which is crucial for plant growth.

Bacteria might help other bacteria to tolerate antibiotics better
A new paper by the Dynamical Systems Biology lab at UPF shows that the response by bacteria to antibiotics may depend on other species of bacteria they live with, in such a way that some bacteria may make others more tolerant to antibiotics.

Two-faced bacteria
The gut microbiome, which is a collection of numerous beneficial bacteria species, is key to our overall well-being and good health.

Microcensus in bacteria
Bacillus subtilis can determine proportions of different groups within a mixed population.

Right beneath the skin we all have the same bacteria
In the dermis skin layer, the same bacteria are found across age and gender.

Bacteria must be 'stressed out' to divide
Bacterial cell division is controlled by both enzymatic activity and mechanical forces, which work together to control its timing and location, a new study from EPFL finds.

How bees live with bacteria
More than 90 percent of all bee species are not organized in colonies, but fight their way through life alone.

The bacteria building your baby
Australian researchers have laid to rest a longstanding controversy: is the womb sterile?

Hopping bacteria
Scientists have long known that key models of bacterial movement in real-world conditions are flawed.

Read More: Bacteria News and Bacteria Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.