Muscat: Omani deserts are rich in microorganisms that can survive extremely high levels of UV and other radiation as well as long-term desiccation (scarcity of water), according to a study carried out by scientists at the Sultan Qaboos University (SQU).
“Many cyanobacteria, types of photosynthetic bacteria, inhabiting Omani deserts are found to contain a special pigment called scytonemin, known to act as a sunscreen for UV (ultra violet) protection,” said Dr. Raeid M. M. Abed, an assistant professor in the SQU’s Department of Biology of the College of Science, in a press release issued here Saturday.
Dr. Abed added that this pigment has been shown to occur in many cyanobacteria in other deserts. He also said that the other cyanobacteria that were not able to produce scytonemin were also detected but were found to hide beneath the scytonemin-containing types.
“Some other bacteria belonging to the genus Deinococcus were also found in Omani deserts. Deinococcus is known for being the most radiation-resistant vegetative cell and in fact it can live through blasts of radiation thousands of times greater than the level that would kill a human being. These bacteria can fragment its DNA into small pieces upon exposure to UV radiation but reassemble it so efficiently when normal conditions are restored”, claimed Dr. Abed.
Dr. Abed has been working for the last 10 years on the diversity and function of microbial communities in various ecosystems from extreme environments. His main focus is studying the diversity of cyanobacteria and aerobic heterotrophic bacteria using molecular techniques.
Desiccation-tolerant cyanobacteria that could survive without water for extended periods of time were also found by way of the studies done by Dr. Abed and his team.
Nostoc spp. were isolated in cultures from Omani deserts and these cyaobacteria were found to survive around two years of desiccation but come back to life as soon as they are wetted with water. “This amazing ability to survive dryness for such a long time is still puzzling at the cellular level and such bacteria are presumably having special proteins and DNA, which awaits further investigations”, Dr. Abed explained. The study performed by Dr. Abed and his team focused on the diversity of microorgansism, their adaptation and role in improving soil stability and productivity in biological soil crusts from Omani deserts. The study revealed many novel and interesting findings.
The researchers employed different techniques such as direct microscopy, enrichment cultivation and state-of-art molecular tools in order to describe the bacterial diversity in Omani deserts. They identified more than 300 different types of bacteria among which cyanobacteria formed around 77–81% of the total microbial communities.
