Monday, March 22, 1999
Do nanobacteria rule Earth and Mars?
By BBC News Online Science Editor Dr David Whitehouse
The most common form of life on Earth may be tiny forms of bacteria, if new research in Australia is confirmed.
And right now they might be living on Mars, as well as in Earth rocks and even inside your body.
A geologist from the University of Queensland claims to have found minute multiplying under her microscope. These would be the first breeding "nanobacteria" identified.
Philippa Uwins has revealed that tiny filaments in sea-floor mineral samples multiplied. She was looking at a clay mineral called illite, which has submicroscopic fibres.
But then a colleague noticed what appeared to be fungus growing on the samples. She went back to her slides and saw spore-like structures that reminded her of germinating bacteria.
Tests are now underway to try to get DNA out of the nanobacteria.
Dr Uwins does not like the word 'nanobacteria' because she doesn't know the evolutionary development of her discoveries. She has called the organisms 'nanobes'.
[Photo text: "The supposed nanomicrobe in the Mars rock" - See the attached file!]
The existence of nanobacteria has been suggested for over 10 years. They were one of the lines of evidence used by Nasa scientists to claim that tiny structures in a Martian rock were fossil bacteria.
Nanobacteria are far smaller than any known bacterium. Indeed, many microbiologists believe they are smaller than the minimum possible size for a living cell.
Some scientists argue that these tiny structures were formed by geological processes, not biological ones. They pointed out that there was no evidence for life forms only 10% of the size of the smallest known microbes on Earth.
But there are scientists who have claimed numerous examples of nanobacteria on Earth. Foremost among them was Dr Robert Folk of the University of Texas.
Nanobacteria everywhere
After looking at mineral deposits near volcanoes he claimed, many years before the Nasa announcement, to have identified bacteria very much smaller than hitherto seen.
He believes that such bacteria form the bulk of living things on Earth and may be responsible for the rusting of metal and the 'greening' of copper.
The NASA team picked up Folk's work when describing the tube-shaped forms they saw in the Martian meteorite as "similar in size and shape to nanobacteria".
But why have nanobacteria escaped biologists' notice if they are so abundant?
Robert Folk believes that the minuscule creatures have simply eluded the conventional tools used to study bacteria.
Inside you
Other research suggests that nanobacteria may have direct effects on humans. They may cause kidney stones
Scientists in Finland claim to have detected them in kidney stones and harmful calcium deposits elsewhere in the body.
A team from the University of Kuopio say that analyses of 30 human kidney-stone specimens has revealed that all of them contained nanobacteria.
The researchers show that nanobacteria grown in the laboratory produce calcium phosphate formations, much like those found in kidney, gall, and bladder stones.
Since they have found that nanobacteria can be grown in a mixture similar to filtered urine, they may provide valuable information for studying and treating kidney stones.