Featured Research

from universities, journals, and other organizations

Study Uncovers Bacteria's Worst Enemy

Date:
April 16, 2005
Source:
DOE/Los Alamos National Laboratory
Summary:
University of California scientists working at Los Alamos National Laboratory have found that the successful use of bacteria to remediate environmental contamination from nuclear waste and processing activities may depend more upon how resistant the bacteria are to chemicals than to how tolerant they are to radioactivity. The results of a recent Laboratory study may help make bacterial bioremediation a more widespread method for cleaning up sites contaminated with actinides and other radionuclides.

LOS ALAMOS, N.M., April 14, 2005 -- University of California scientists working at Los Alamos National Laboratory have found that the successful use of bacteria to remediate environmental contamination from nuclear waste and processing activities may depend more upon how resistant the bacteria are to chemicals than to how tolerant they are to radioactivity. The results of a recent Laboratory study may help make bacterial bioremediation a more widespread method for cleaning up sites contaminated with actinides and other radionuclides.

In research published in the journal Environmental Microbiology, Laboratory chemist Mary Neu and her colleagues describe their study of different naturally occurring bacteria used to treat actinide contamination. Actinides are the elements above atomic number 89 and are usually radioactive. The study's results indicate that actinide toxicity is primarily chemical, rather than radiological, and so a bacteria's resistance to radiation does not necessarily ensure a tolerance for radionuclides. In fact, the bacteria's worst enemy in a nuclear waste site may not be the radioactive elements, but rather, the other toxic metals that might also be found at the site.


The study also shows that contrary to the conventional wisdom, when it comes to these environmental bacteria, plutonium is less toxic than uranium and, in general, actinides are less toxic than other types of metals. This suggests that actinide toxicity will not impede bioremediation using naturally occurring bacteria.

"This study" said Neu, "is exciting because even though we've known for years that bacterial bioremediation can be a preferred method for cleaning up actinide contamination, we've never really known whether or not radioactivity or chemical toxicity will stifle the process. Our study found that actinides are chemically toxic to bacteria only at high levels far, far above concentrations at contaminated sites, and that common toxic metals, such as cadmium, nickel, and chromium, are more likely to cause problems for the bacteria."

Generally, bacteria used for bioremediation are selected to target a specific form and oxidation state of toxic pollutants, such as soluble hexavalent uranium carbonate for uranium contamination. However, a single chemical rarely contaminates soils and groundwater and combinations of actinides, radionuclides, organic chemicals and metal regularly exist at many nuclear sites. Based on the results of this study, if bioremediation is to be effective at these types of sites, the operative microorganisms must be able to grow, function and do better than other bacteria in the presence of all kinds of contaminants.

The study examined the effects of toxicity of actinides, metals and chelators on different bacteria being evaluated for radionuclide bioremediation, Deinococcus radiodurans and Pseudomonas putida, along with the toxicity of plutonium on the bacteria Shewanella putrefaciens.

In addition to Neu, the bacteria bioremediation study team includes Christy Ruggiero and Hakim Boukhalfa of the Chemistry Division, and Joseph Lack and Larry Hersman from the Laboratory's Bioscience Division.

Los Alamos National Laboratory is operated by the University of California for the National Nuclear Security Administration of the U.S. Department of Energy and works in partnership with NNSA's Sandia and Lawrence Livermore national laboratories to support NNSA in its mission.

Los Alamos enhances global security by ensuring the safety and reliability of the U.S. nuclear deterrent, developing technologies to reduce threats from weapons of mass destruction, and solving problems related to defense, energy, environment, infrastructure, health and national security concerns.


Story Source:

The above story is based on materials provided by DOE/Los Alamos National Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

DOE/Los Alamos National Laboratory. "Study Uncovers Bacteria's Worst Enemy." ScienceDaily. ScienceDaily, 16 April 2005. <www.sciencedaily.com/releases/2005/04/050416111147.htm>.
DOE/Los Alamos National Laboratory. (2005, April 16). Study Uncovers Bacteria's Worst Enemy. ScienceDaily. Retrieved September 19, 2014 from www.sciencedaily.com/releases/2005/04/050416111147.htm
DOE/Los Alamos National Laboratory. "Study Uncovers Bacteria's Worst Enemy." ScienceDaily. www.sciencedaily.com/releases/2005/04/050416111147.htm (accessed September 19, 2014).

Share This



More Plants & Animals News

Friday, September 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Elephant Undergoes Surgery in Tbilisi Zoo

Raw: Elephant Undergoes Surgery in Tbilisi Zoo

AP (Sep. 18, 2014) Grand the elephant has successfully undergone surgery to remove a portion of infected tusk at Tbilisi Zoo in Georgia. British veterinary surgeons used an electric drill to extract the infected piece. (Sept. 18) Video provided by AP
Powered by NewsLook.com
Chimp Violence Study Renews Debate On Why They Kill

Chimp Violence Study Renews Debate On Why They Kill

Newsy (Sep. 17, 2014) The study weighs in on a debate over whether chimps are naturally violent or become that way due to human interference in the environment. Video provided by Newsy
Powered by NewsLook.com
Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

AFP (Sep. 16, 2014) Scientists say a female colossal squid weighing an estimated 350 kilograms (770 lbs) and thought to be only the second intact specimen ever found was carrying eggs when discovered in the Antarctic. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins