Thursday, March 19, 2009

Three new bacteria species found in stratosphere.

Three new bacteria species found in stratosphere.
Dr. Nitish Priyadarshi

Three new species of bacteria, which are not found in the earth and highly resistant to ultraviolet radiation, have been discovered in the Upper Stratosphere( more than 15 km. above the earth) by India scientists, according to the India Space Research Organisation (ISRO).
While one of the species has been named Janibacter Hoylei after astrophysicist Fred Hoyle, the second has been christened Bacillus isronensis.
The third has been named Bacillus Aryabhata after the India astronomer.

Studying of bacteria is now becoming very important for space flight safety. It is necessary to know the methods to maintain cosmonauts’ immunity, what drugs should be offered to them, and what new bio-stable materials should be developed for spaceship compartments and equipment.

Bacteria in space become more aggressive, and can “eat” spaceship components. This happens because microorganisms start producing enzymes unusual for them in terrestrial conditions, which destroy structural materials.

Studies have shown that space conditions suppress the human immune system, making the body more susceptible to infection. Further, weightlessness and higher levels of radiation may increase the mutation rate in bacteria. This could result in making some organisms more resistant to antibiotics or perhaps causing others that are normally harmless to become infectious.
Many researches are being carried out to understand how bacteria behave in space. In an experiment aboard NASA's space shuttle Atlantis September 2006, scientists at Arizona State University sent sealed tubes of salmonella (culprit in food poisoning) into space to measure changes in genetic responses and disease-causing potential.
After the bacteria returned to Earth, the researchers examined the salmonella's gene and protein expression patterns, and their effect on virulence. Compared to the Earth-bound bacteria, the space-travelling Salmonella had changed expression of 167 genes.
Animal studies showed that bacteria flown in space were almost three times as likely to cause disease compared to control bacteria grown on the ground.
These results have important implications for human health since salmonella (and other gut-related bacterial pathogens) are a leading cause of foodborne illness and infectious disease, especially in the developing world. There's currently no vaccine for salmonella food borne infections in humans.
While the present study of ISRO 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.

The Hindu news paper, New Delhi, March17, 2009.
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