Most of the discoveries all over the world has occurred by chance and when they were least expected. An experiment was going on at the Orego...
It is a non-pathogenic bacteria meaning thereby that it does not causes disease. It is found everywhere; in sewage, furniture, fomites etc. The great relief is its non-disease producing property. The Dienococcus is genus and radiodurans is a species name. It has so many other brother and sisters from the same genus. It can survive not only high doses of radiation but can also withstand extreme cold, heat, desiccation, freezing also. That’s why it is labelled as an Extremophilic bacterium. The secret of this amazing property is its DNA. There are many copies of DNA in this bacteria, the human being is having only one. Not only that they have very efficient repair system of damaged DNA. The damaged DNA is taken to a separate area where it is repaired.
The scientists have shown a great interest in studying this bacterium, due to its miraculous properties. There are two main fields where this bacteria can be used, and they are bioremediation and in biomedical field.
The bioremediation refers to a process where microorganism, fungi, plant or enzyme are used to restore the contaminated environment to its natural state. In and around the nuclear power plant the soil, sediment and water may be contaminated by the nuclear waste. This nuclear waste contains toxic metals and radionuclide like chromium, lead, mercury, the toxic solvent like benzene, toluene, xylenes and chlorinated hydrocarbons etc. The decontamination of such sites poses a real challenge. The existing cleanup technologies are expensive, dangerous and not very efficient. The alternative is to use specialized microorganisms that can detoxify the metallic and organic elements, and make the environment harmless. If we use the common organisms they perish to the high dose of irradiation. The D. Radiodurans is being experimented to decontaminate such sites with good success. It is engineered genetically to consume and digest the solvent and heavy metals in radioactive environment. One such example is mercuric reductase gene cloning from E.Coli to Dienococcus. This genetically engineered bacterium can detoxify the ionic mercuric residue. Such residues are a waste generated from nuclear weapon plants. Yet another strain of it can detoxify both mercury and toluene in mixed radioactive waste. Genetically engineered strain of D.radiodurans is also found useful in precipitation of uranium in acid and alkaline solutions. Thus it has already established its usefulness in the field of bioremediation.
Ageing and cancers are two burning challenges to the scientists. Both are associated with increased DNA and protein oxidation due to free radical generation. As the age advances the ability of cell to repair also declines. The focal point of aging and cancer research is to identify factors that antagonize the aging process and carcinogenesis. It will open a new pathway to design an appropriate therapeutic strategy. The study of D. radiodurans helps to understand the process and may help in developing an all new strategy. One thing is already known that in the ageing and carcinogenesis the physiological changes bring about damage to DNA and weaken the defence and repair mechanism of cell. A lesson can be learned from D.radiodurans about its ability to repair the oxidative damage. In the ageing and cancers there is production of free radicals. Alzheimer’s and Parkinson’s diseases are also associated with oxidative damages to both DNA and proteins. Thus, an efficient repair system is a critical component of its management. The ability of D.radiodurans to combat the oxidative damage can be harnessed to manage such situations. It may delay ageing, and repair the damaged cells after chemo and radiotherapy.
Source: Dr. Sujan Narayan Agrawal, Satyaram Satpathy & Debashish Samal. Deinococcus Radiodurans: The World’s Toughest Bacterium. A Review. GJMR(C) 2020; 20(2): pp 1- 4.
DOI: https://doi.org/10.34257/GJMRCVOL20IS2PG1
About authors and Co-authors: The author Dr Sujan Narayan Agrawal is presently working as Professor, Department of Surgery, BRKM Government Medical College, Jagdalpur (Bastar) Chhattisgarh. INDIA. There are more than 30 scientific publications to his credit on various aspects of medical science. He has reviewed more than 100 manuscripts for National and International journals. He is a voracious reader and prolific writer. Being a surgeon but writing about a topic in microbiology shows his appetite for knowledge.
The Co-Authors Shri Satyaram Satapathy and Debashish Samal are Demonstrators in the Department of Microbiology. They and their team have successfully established a new virology lab for the screening of COVID patients recently.
