Featured Research

from universities, journals, and other organizations

Bacterium Transforms Toxic Gold Compounds To Their Metallic Form

Date:
October 9, 2009
Source:
European Synchrotron Radiation Facility
Summary:
Australian scientists have found that the bacterium Cupriavidus metallidurans catalyzes the biomineralization of gold by transforming toxic gold compounds to their metallic form using active cellular mechanism.

A C. metallidurans ultra-thin section containing a gold nanoparticle.
Credit: Reith et al, PNAS 5-9 October 2009.

Australian scientists have found that the bacterium Cupriavidus metallidurans catalyses the biomineralisation of gold by transforming toxic gold compounds to their metallic form using active cellular mechanism.

Researchers reported the presence of bacteria on gold surfaces but have never clearly elucidated their role. Now, an international team of scientists has found that there may be a biological reason for the presence of these bacteria on gold grain surfaces.

“A number of years ago we discovered that the metal-resistant bacterium Cupriavidus metallidurans occurred on gold grains from two sites in Australia. The sites are 3500 km apart, in southern New South Wales and northern Queensland, so when we found the same organism on grains from both sites we thought we were onto something. It made us wonder why these organisms live in this particular environment. The results of this study point to their involvement in the active detoxification of Au complexes leading to formation of gold biominerals,” explains Frank Reith, leader of the research and working at the University of Adelaide (Australia).

The experiments showed that C. metallidurans rapidly accumulates toxic gold complexes from a solution prepared in the lab. This process promotes gold toxicity, which pushes the bacterium to induce oxidative stress and metal resistance clusters as well as an as yet uncharacterized Au-specific gene cluster in order to defend its cellular integrity. This leads to active biochemically-mediated reduction of gold complexes to nano-particulate, metallic gold, which may contribute to the growth of gold nuggets.

For this study scientists combined synchrotron techniques at the European Synchrotron Radiation Facility (ESRF) and the Advanced Photon Source (APS) and molecular microbial techniques to understand the biomineralisation in bacteria. It is the first time that these techniques have been used in the same study, so Frank Reith brought together a multinational team of experts in both areas for the success of the experiment. The team was made up of scientists from the University of Adelaide, the Commonwealth Scientific and Research Organization (CSIRO), the University of California (US), the University of Western Ontario and the University of Saskatchewan (Canada), Martin-Luther-Universitδt (Germany), University of Nebraska-Lincoln (US), SCK.CEN (Belgium) and the APS (US) and the ESRF (France).

This is the first direct evidence that bacteria are actively involved in the cycling of rare and precious metals, such as gold. These results open the doors to the production of biosensors.

“The discovery of an Au-specific operon means that we can now start to develop gold-specific biosensors, which will help mineral explorers to find new gold deposits. To achieve this we need to further characterize the gold-specific operon on a genomic as well as proteomic level. If funding for this research is granted I believe we can produce a functioning biosensor within three to five years,” concludes Reith.


Story Source:

The above story is based on materials provided by European Synchrotron Radiation Facility. Note: Materials may be edited for content and length.


Cite This Page:

European Synchrotron Radiation Facility. "Bacterium Transforms Toxic Gold Compounds To Their Metallic Form." ScienceDaily. ScienceDaily, 9 October 2009. <www.sciencedaily.com/releases/2009/10/091007103034.htm>.
European Synchrotron Radiation Facility. (2009, October 9). Bacterium Transforms Toxic Gold Compounds To Their Metallic Form. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2009/10/091007103034.htm
European Synchrotron Radiation Facility. "Bacterium Transforms Toxic Gold Compounds To Their Metallic Form." ScienceDaily. www.sciencedaily.com/releases/2009/10/091007103034.htm (accessed September 30, 2014).

Share This



More Plants & Animals News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

California University Designs Sustainable Winery

California University Designs Sustainable Winery

Reuters - US Online Video (Sep. 27, 2014) — Amid California's worst drought in decades, scientists at UC Davis design a sustainable winery that includes a water recycling system. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com
Argentina Worries Over Decline of Soybean Prices

Argentina Worries Over Decline of Soybean Prices

AFP (Sep. 27, 2014) — The drop in price of soy on the international market is a cause for concern in Argentina, as soybean exports are a major source of income for Latin America's third largest economy. Duration: 01:10 Video provided by AFP
Powered by NewsLook.com
Mama Bear, Cubs Hang out in California Backyard

Mama Bear, Cubs Hang out in California Backyard

Reuters - US Online Video (Sep. 27, 2014) — A mama bear and her two cubs climb trees, wrestle and take naps in the backyard of a Monrovia, California home. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com
'Crazy' Climate Forces Colombian Farmers to Adapt

'Crazy' Climate Forces Colombian Farmers to Adapt

AFP (Sep. 26, 2014) — Once upon a time, farming was a blissfully low-tech business on Colombia's northern plains. Duration: 02:05 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:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

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