Researchers from the University of Manchester, US, have decoded the genetic code of the Fungus belonging to the family Aspergillus. This has been the major cause of death due to secondary infection in patients suffering from leukemia and those who have undergone marrow transplants.
This research is primarily focused on the idea of saving lives of millions of people by developing new drugs which could arrest these fungal infections. Three different species were studied; they are Aspergillus fumigatus, Aspergillus nidulans and Aspergillus oryzae. It was very surprising to know that they were very different genetically.
This was established when their genome was completely mapped and published in the science magazine Nature. The genetic maps were as different as that of the man and fish.
Aspergillus is a very common air-borne fungus, carried all over the world as
spores. Although usually harmless, the species Aspergillus fumigatus was
identified as a cause of infection as long ago as 1848 and is now the
leading infectious cause of death in vulnerable leukemia and bone marrow
Aspergillus nidulans has been a leading experimental system helping to
unravel many fundamental cellular processes for the last 50 years, whilst
Aspergillus oryzae has been used in the Far East for 2000 years to produce
sake (rice wine), miso (soybean paste) and shoyu (soy sauce).
The researchers have found that the three species only display around 68
percent of the same proteins, a similar percentage to that shared by mammals
and fish which diverged 450 million years ago. They also differ considerably
in genome size, with Aspergillus oryzae being 31 percent bigger than
Aspergillus fumigatus and 24 percent bigger than Aspergillus nidulans.
"Fungi play a critical role in the earth's ecosystem, being responsible for
almost all degradation of plant material as well as recycling nitrogen.
Aspergillus fumigatus is a major constituent of compost, and mould fungi
have been important sources of drugs including penicillin and cyclosporin,"
said The David Denning, who coordinated the project.
However, they also produce toxins known as mycotoxins, such as aflatoxin which can cause liver cancer. Aspergillus causes a life-threatening infection for transplant and leukemia patients, as well as being a major allergen for asthmatics.
"Identifying these genome sequences will transform scientific understanding
of why this group of fungi is so lethal and allergenic. The importance of
the project in helping develop new drugs and diagnostic tests, and
understand and prevent allergies and diseases like pneumonia and sinusitis,
cannot be overestimated. The information revealed will also develop our
understanding of the biology of composting and mycotoxin production, and
provide benefits for many other areas of science and medicine," Denning
said. (edited ANI)