And I'm talking about something much more interesting than Jesus: the bacterium Deinococcus radiodurans
Deinococcus radiodurans is a bacterium capable of surviving in most extreme life conditions, including radiation dozes up to 5 000 times higher than those lethal for humans. Extreme radiation cleaves DNA cells into hundreds of fragments, which means death for the cell. The bacterium Deinococcus radiodurans is the only one to have "learned" how to reassemble, in an appropriate sequence, all the hundreds of pieces of its DNA into a functioning genome, and Radman's team has figured out how the process of surviving the death functions. Source: Radman "revives" dead cell
September 28th 2006
A group of researchers lead by Professor Miroslav Radman has discovered a mechanism enabling the "clinically dead" cell of the bacterium Deinococcus radiodurans to "rise from the dead". The discovery of Professor Radman and his colleagues will be published on October 5th in the "Nature", a world's leading science journal.
As the discovery is estimated to strike a responsive chord among scientists, the editorial board of the "Nature" issued a release to leading global media one week ahead.
Deinococcus radiodurans is an extremophile bacterium, which means that it is adapted to extreme life conditions. For instance, it is capable of surviving in both desert sand and rocky landscape, where extreme desiccation and long-term exposure to the UV radiation emitted by the sun would make the survival of any other organism impossible.
- Extreme bouts of desiccation and ionizing radiation cleave the DNA of each cell in into hundreds of pieces, including the cell of Deinococcus radiodurans. However, only the bacterium Deinococcus has learned how to reassemble all the hundreds of fragments of its DNA in the appropriate sequence. Thus, Deinococcus has developed the ability to "survive the death", and we have figured out how this process works – says Miroslav Radman, Professor at the Necker Medical School in Paris and founder of the Mediterranean Institute for Life Sciences (MedILS) in Split.
Professor Radman was leading the research, in which another three Croatian researchers were involved Ksenija Zahradka (38), Dea Slade (25) and Mirjana Petranovic; (59) from the Institute "Rudjer Boškovic" in Zagreb. Molecular biologist Ksenija Zahradka, PhD., is the first author of the study to be published in the "Nature".
- We started the research back in 2002, during my postdoctoral study in the laboratory of Professor Radman in Paris. After returning to Zagreb, I continued the work in my home laboratory at the Rudjer Boškovic; Institute, in collaboration with Professor Mirjana Petranovic;, who has been my mentor for many years, and young and gifted molecular biologist Dea Slade. I am very happy and proud that the years of work under the leadership of Professor Radman resulted in such a success – says Ksenija Zahradka, announcing the continuation of research into extremophiles together with Professor Radman.
The discovery of the Croatian scientists is interesting because of many potential areas of application, as the process could be used for, among others, developing new drugs. – As an entirely harmless, desiccation-resistant bacterium, it may turn into the vector gene for bioremediation – environmental cleaning by means of targeted application of enzymes for decomposition of waste.
I am personally more interested in learning from Deinococcus how to bringing back to life our dead and half-dead neurons. I believe that the DNA repair mechanism that we found in this bacterium could open the door to new regenerative medicine. Finally, I consider Deinococcus No. 1 candidate for "planting" life on sterile planets – says Professor Radman, with two addresses placed under his study for the "Nature": the address of the Paris Laboratory for Evolutionary and Medical Molecular Genetics and the address of the MedILS in Split.
- I would like to underline that over 50 per cent of the experiments were done by Doctor Ksenija Zahradka at the Rudjer Boškovic Institute in Zagreb. This is the best answer to the question whether Croatia is a place for excellent scientific research – emphasizes Professor Radman, adding that a press conference will be held in Paris on October 5th, the publication date of the study in the "Nature".
- I believe that Inserm (the French National Institute for Health and Medical Research), Rudjer and MedILS will set up the strongest Deinococcus research group already this year. I very much look forward to the cooperation with physicists, whose knowledge is necessary for us to understand the molecular basis of desiccation, or extreme dehydration. Namely, dehydration is the most acute life hazard, and any significant research into this area is very scarce – concludes Radman. First Scientist to Read the Genetic Code Surpassed
The bacterium Deinococcus radiodurans was discovered some 50 years ago as a contaminant in meat cans sterilized by gamma radiation dozes 3 000 to 5 000 times higher than those lethal for humans. Over the past fifty years scientists have unsuccessfully tried to unveil the mysterious repair of scattered DNA.
Interestingly enough, Deinococcus radiodurans has over the past few years been the focus of interest of famous Craig Venter, whose former biotech firm Celera Genomics was the first to read the human genetic code in April 2000. Venter established a private institute several years ago, at which he studies, among other issues, Deinococcus radiodurans with Hamilton Smith, the Nobel Prize winner, and three hundred researchers. However, the group lead by Professor Radman was the first to unveil the secret.
- My first study of Deinococcus radiodurans started several years ago, while Ksenija Zahradka was engaged in her postdoctoral study in my Paris laboratory. Dea Slade, preparing her doctoral thesis under my mentorship, jointed us later on. The research was funded based on an agreement with Pliva. The project was more than risky, and the drawing up of the study for the "Nature" took more than one year – says Miroslav Radman.