Deinococcus Radiodurans Facts: You Should Know About This

A radiation-resistant organism, Deinococcus Radiodurans, is called a polyextremophile.

It can sustain in extreme weather conditions like vacuum, cold, dehydration, and acid. The bacterium's resistant capabilities have often puzzled biologists as no living organism could have survived such intense radiation in any natural scenario.

This capability of the bacterium has helped it create world records. Read on to discover more interesting facts about Deinococcus Radiodurans.

History Of The Bacterium

Arthur Anderson discovered D. Radiodurans in 1956. The bacteria was discovered from a tin of ground meat spoiled after being exposed to a high dose of radiation. A non-spore-forming, gram-positive aerobe needs a compound media to produce its colonies. The bacterium cells stain Gram-positive, but its cell envelope reminiscences the Gram-negative bacteria's cell walls.

A spherical bacterium, it can be easily cultured. It acquires oxygen from organic compounds available in its surroundings. Its habitat is often rich in organic materials, like meat, sewage, soil, or feces, and scientists have also isolated it from dust, dried food, and textiles, among other objects.

Viewing it by electron microscopy revealed the bacterium's tetrad structure. In the early development stage, it has two cell structure that develops into four cell structure in a later stage. Many biologists believe its resistance to radiation exposure is a by-product of its way of dealing with dehydration.

Scientists View And Scientific Aspects

D. Radiodurans can be used in several fields of investigation. Research has found that this bacterium can play a significant role in bioremediation applications, biomedical research, and nanotechnology.

Bioremediation involves using microorganisms to restore an environment that has been contaminated by toxic chemicals, heavy metals into its natural condition. However, ionizing radiation restricts the use of several microorganisms to clean nuclear waste. This is where D. Radiodurans comes into the picture.

Its high resistance makes it useful in nuclear energy waste treatment. The bacterium has been genetically engineered by cloning its mercuric reductase gene from Escherichia coli to enable the bacterium to detoxify the mercury residue detected in radioactive waste left behind by the manufacturing of nuclear weapons.

Also, because of its high resistance and easy adaptability, this bacterium was chosen to test the Martian surface of other planets.

In the biomedical field, bacteria have become useful in studying the patterns and procedures that lead to cancer and aging.

The leading cause of these issues remains connected to damages in RNA, DNA, and protein due to oxidative stress, weak antioxidant defense, and repair mechanism's inability to control damage created by reactive oxygen species (ROS).

Here, D. Radiodurans can be used in research works considering its resistance to oxidative damage and DNA repairing ability for developing solutions to prevent cancer and aging.

Studies are also ongoing to apply this bacterium in human cells to avert ROS damage and the possibility of tumoral cells becoming resistant to radiation.

Evolution Of The Bacterium

The complete genome sequence of Deinococcus Radiodurans is composed of two chromosomes - a megaplasmid and a small plasmid. They yield a total genome of 3,284 156 base pairs. Other microbes like Micrococcus Luteus and Micrococcus Sodonensis also contain more than one genome, but they are radiosensitive. This makes Deinococcus Radiodurans very special.

This bacterium has a special quality to repair both double and single-stranded DNA. When its cell is damaged, it deals with DNA damage by bringing the DNA inside a compartmental ring-like structure. After the DNA repair is complete, it fuses the nucleoids present outside the compartment with the DNA.

These bacteria are extremely resistant to oxidative damage, high levels of ionizing, genotoxic chemicals, and ultraviolet radiation. The organism can stitch back its fragments just after a few hours of D. Radiodurans genome getting shattered by high doses of radiation.

This bacterium lines up copies of its genome to ensure identical DNA sequences are close to each other. Studies have found that the presence of RecA protein in the bacterium has worked as a catalyst in its DNA repair process.

Distinctive features of the Deinococcus genome and radiation-resistant abilities have made it a topic of interest among scientists and biologists. Experts found that the D. Radiodurans genome is enriched in repetitive sequences compared to other bacteria.

FAQs

Q: What does Deinococcus Radiodurans cause?

A: Deinococcus Radiodurans do not cause any disease.

Q: How long does Deinococcus Radiodurans live?

A: The world's toughest bacterium, Deinococcus Radiodurans, can survive any extreme weather conditions, be it cold, acid, vacuum, or dehydration. According to studies, it can survive for around three years in outer space.

Q: What does Deinococcus Radiodurans eat?

A: Deinococcus Radiodurans flourish in an aerobic environment. They use a vast array of amino acids, sugar, and organic acids as a carbon source for catabolism. They eat anything and everything they can.

Q: How does Deinococcus Radiodurans survive vacuum?

A: The strategies used by this microorganism to protect itself from the vacuum are yet unknown. However, when dried Deinococcus Radiodurans cells were exposed to a high vacuum (10-4–10-7 Pa), their survival was 2.5 fold lower than control cells.

Q: Which are tougher tardigrades or Deinococcus Radiodurans?

A: Deinococcus Radiodurans is considered the world's toughest bacteria.

Q: What disease does Deinococcus Radiodurans cause?

A: Deinococcus Radiodurans does not apparently cause any disease.

Q: Why is Deinococcus Radiodurans so resistant to ionizing radiation?

A: Deinococcus Radiodurans can do DNA repair caused during dehydration. This makes the bacterium so much resistant to ionizing radiation.