Recent discoveries by researchers at the Uniformed Services University of the Health Sciences (USU) could lead to new avenues of exploration for radioprotection in diverse settings. Michael J. Daly, Ph.D., an associate professor in USU's Department of Pathology, and his colleagues have uncovered evidence pointing to the mechanism through which the extremely resilient bacterium Deinococcus radiodurans protects itself from high doses of ionizing radiation (IR). The results of the recent study, titled "Protein Oxidation Implicated as the Primary Determinant of Bacterial Radioresistance" were published in the March 20 edition of PLoS Biology.
These discoveries likely will cause a shift in D. radiodurans research, changing the focus from DNA damage and repair toward a potent form of protein protection. These findings point to new avenues of exploration for radioprotection, which could eventually influence how individuals are treated for exposure to chronic or acute doses of radiation; could lead to ways to protect cancer patients from the toxic effects of radiation therapy; and may prove significant in efforts to contain toxic runoff from radioactive Cold War waste sites.
Fifty years ago, scientists discovered D. radiodurans, leading to speculation that the incredible degree of resistance exhibited by the bacteria has to do with its mechanism of DNA repair, and the majority of research on the bacteria has centered on this hypothesis. However, D. radiodurans has subsequently shown nothing obviously unusual in its DNA repair components, and it appears that bacteria at differing levels of resistance sustain the same amount of DNA damage from a given dose of IR. Additionally, many bacteria are killed by IR doses that actually cause very little DNA damage.
In a 2004 study, Daly and colleagues found that resistant and sensitive bacterial cells had significantly different metal concentrations, pointing to high levels of manganese and low iron levels as possible influences on cellular recovery following irradiation. The team showed that the most resistant bacterial species contained approximately 300 times more manganese and three times less iron than the most sensitive species. In the new study, which examined the functional consequences of this disparity, the researchers demonstrated that high cytosolic manganese and low iron concentrations enable resistance by protecting proteins, but not DNA, from IR-induced oxidative damage.
Lisa Reilly | EurekAlert!
Antimicrobial substances identified in Komodo dragon blood
23.02.2017 | American Chemical Society
New Mechanisms of Gene Inactivation may prevent Aging and Cancer
23.02.2017 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
23.02.2017 | Physics and Astronomy
23.02.2017 | Earth Sciences
23.02.2017 | Life Sciences