Wednesday, April 20, 2011

Bacteria in space to throw light on origin of life

By Syed Akbar
In a major discovery which may ultimately throw some light on the origin of life, a team of Indian scientists has collected three new species of bacteria from the sky.

We all know that the Earth is filled with viruses, bacteria and micro-organisms, besides other life forms. Many, however, do not know that some of the micro-organisms live in the Earth's atmosphere, up in the sky. Scientists believe that a thorough study of these creatures living in the upper stratosphere (the area of ozone) will reveal the secrets of the origin of life on the human planet.

Incidentally, the three new species of bacteria discovered by the Indian group are not found on the Earth. Since these bacteria have made the stratosphere or ozone layer portion as their abode, they have developed resistance to the harmful ultra violent rays. That they survive in the dangerous radiation is in itself a marvel, and scientists want to unravel this marvel, mystery.

If we could know how these bacteria survive the intense radiation up in the sky, we can probably device some methods to keep ourselves free from the harmful effects of radiation. Then no nuclear war will hurt us at least bodily, with our skin being intact. Of course, the dangers of genetic damage due to radiation still persists in case of nuclear holocaust.

The new species of bacteria were found by scientists from the Indian Space Research Organisation and the Tata Institute of Fundamental Research. What the scientists from these two organisations did was to send atmospheric balloons from the National Balloon Facility in Hyderabad. The new organisms have been named after famous astrophysicist Fred Hoyle (Janibacter hoylei), ISRO (Bacillus isronensis) and after ancient Indian astronomer Aryabhata (Bacillus aryabhata).

According to ISRO scientists, the experiment was conducted using a 26.7 million cubic feet balloon carrying a 459 kg scientific payload soaked in 38 kg of liquid neon. The scientific equipment included a cryo (cold) sampler containing 16 evacuated and sterilised stainless steel probes. Throughout the flight, the probes remained immersed in liquid neon to create a cryopump effect.

These cylinders, after collecting air samples from different heights ranging from 20 km to 41 km, were parachuted down and safely retrieved. These samples were analysed by scientists at the Centre for Cellular and Molecular Biology, Hyderabad, as well as the National Centre for Cell Science, Pune, for independent examination.

"In all, 12 bacterial and six fungal colonies were detected, nine of which, based on 16S RNA gene sequence, showed greater than 98 per cent similarity with reported known species on earth. Three bacterial colonies, namely, PVAS-1, B3 W22 and B8 W22 were, however, totally new species. All the three newly identified species had significantly higher UV resistance compared to their nearest phylogenetic neighbours," an official statement from ISRO said.

The scientists said the precautionary measures and controls operating in this experiment inspire confidence that these species were picked up in the stratosphere. "While the present study does not conclusively establish the extra-terrestrial origin of micro-organisms, it does provide positive encouragement to continue the work in our quest to explore the origin of life," they said.

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