Учёные научились превращать яд в золото

Wednesday, 28 January 2004



Microbes grow gold in the lab that buds and bubbles (Frank Reith)


Microbes that grow gold grains looking like a coral reef could open up new possibilities for mineral prospecting, according to an Australian researcher.

Frank Reith from the Australian National University in Canberra and Cooperative Research Centre for Landscape Environments and Mineral Exploration grew these 'bubbly' formations in the lab.

As part of his doctoral thesis Reith looked at the metal-munching microbes involved and how they grow gold grains and nuggets in mines.

He also published his research in the latest issue of the Australasian Institute of Mining and Metallurgy's publication the AusIMM Bulletin.

Gold is usually found in ore bodies, or in waterborne or alluvial deposits that have collected and concentrated gold by physical processes. These processes include gold grains rolling down a stream bed.

Scientists know that microorganisms are involved in dissolving trace amounts of gold out of rock, which Reith's research confirmed.

Gold in the quartz vein at the Tomakin mine on the south coast of New South Wales is invisible, even to high-powered electron microscopes, said Reith.

The gold is hidden in sulfur-rich metal minerals, until the microbes remove it from the rock atom by atom.

But Reith suggested the microbes played another important role: transporting and precipitating gold to form grains and nuggets that collect in alluvial deposits.

He found traces of the microbes' genetic material on the deposits, which confirmed they were present.

Coloured scanning electron micrograph of a gold flake produced by microbes (Frank Reith)

Reith then took some of the microbes from the mine and used them to 'grow' gold in the lab.

"The gold grains grow like a coral reef," Reith told ABC Science Online. "There is a mother cell, which produces buds, forming a bubbly formation."

Reith said the microbes at the surface of these formations could still be hard at work, forming new gold layers on top of the past generation's fossilised gold deposit.

Marker for gold
Reith suggested that the presence of the gold-digging microbes could be used as an environmentally friendly marker for geological exploration.

Looking at past geophysical data for signs of the microbes could prompt further exploration of an area where there is no visible gold deposit, he said.

"It would never substitute for other methods but it could be an add-on," said Reith. "If you found a lot of these organisms in the field you [would be able to] tell that there is some sort of mineralisation there."

Reith said the next step in his research would be to extract genetic material from the microbes to identify the species. He suspects they belong to the genus Pedomicrobium, which contains microbes known to dissolve other metals.

"It's very hard to pinpoint certain organisms; there are millions growing in the soil," he said.

Dr Dennis Gee, chief executive of the research centre involved in the research, said the process Reith unearthed could apply to the main alluvial gold fields in Victoria, at Bathurst in New South Wales, in the Northern Territory and possibly at Coolgardie in Western Australia.

The research could also be important in processing gold from ores that are hard to dissolve, said Gee. These make up one-third of all Australia's gold reserves.

Всё золото на планете производится бактериями,это результат их деятельности.
Они перерабатывают планктон и растворяют в своих желудках всё,но золото проходит и скапливается вокруг них образуя всё растущие самородки.Поэтому все они пористые под микроскопом.

Луженые видать желудки у бактерий, да и зубы будь здоров,планктон жевать.Этож надо всё переварить и золотом нагадить,причём вокруг себя! Чудеса да и только.

http://www.abc.net.au/science/news/enviro/EnviroRepublish_1032376.htm