Radiation-resistant organism reveals its defense strategies

Rehovot, Israel January 9, 2003 Weizmann Institute scientists have found what makes the bacterium Deinococcus radiodurans the most radiation-resistant organism in the world: The microbe's DNA is packed tightly into a ring. The findings, published in the January 10 issue of Science, solve a mystery that has long engaged the scientific community.

The red bacterium can withstand 1.5 million rads a thousand times more than any other life form on Earth and three thousand that of humans. Its healthy appetite has made it a reliable worker at nuclear waste sites, where it eats up nuclear waste and transforms it into more disposable derivatives. The ability to withstand other extreme stresses, such as dehydration and low temperatures, makes the microbe one of the few life forms found on the North Pole. It is not surprising, then, that it has been the source of much curiosity worldwide, recently leading to a debate between NASA and Russian scientists the latter saying that it originated on Mars, where radiation levels are higher.

Since DNA is the first part of a cell to be damaged by radiation and the most lethal damage is the breakage of both DNA strands, scientists have focused on DNA repair mechanisms to find the answer to the microbe's resilience. Cells, including human cells, can mend only very few such breaks in their DNA. Microbes, for example, can repair only three to five. Yet D. radiodurans can fix more than 200. Thus scientists believed that the microbe must possess uniquely effective enzymes that repair DNA. However, a series of experiments showed that the microbe's repair enzymes were very similar to those existing in ordinary bacteria.

Using an assortment of optical and electron microscopy methods, Prof. Avi Minsky of the Weizmann Institute of Sciences Organic Chemistry Department found that the microbe's DNA is organized in a unique ring that prevents pieces of DNA broken by radiation from floating off into the cell's liqu

Contact: Jeffrey J. Sussman
American Committee for the Weizmann Institute of Science

Page: 1 2 3

Related biology news :

1. Scientists sequence genome of kind of organism central to biospheres carbon cycle
2. Unicellular organisms contribute more nitrogen to ocean that reported earlier
3. NHGRI adds 18 organisms to sequencing pipeline
4. Fish no exception to trend in marine-organism disease
5. Scientists urge caution when releasing engineered organisms into environment
6. Marsupial among model organisms next in line for sequencing
7. Study of primitive life form expected to provide clues to biological processes in higher organisms
8. Workshop takes systems view of information processing in organisms
9. Scientists determine identity, cell locale and quantity of nearly all proteins in an organism
10. UC Riverside to convene conference on genetically modified organisms, Oct. 14-17, 2003
11. Stay-at-home microbes: New study finds micro-organisms more complicated than we thought

Post Your Comments:

(Date:11/18/2015)... --> --> ... report titled  Gesture Recognition Market - Global Industry Analysis, ... to the report, the global gesture recognition market was valued at ... US$29.1 bn by 2021, at a CAGR of 20.3% ... dominated the global gesture recognition market in ...
(Date:11/16/2015)... Nov 16, 2015  Synaptics Inc. (NASDAQ: ... solutions, today announced expansion of its TDDI product ... touch controller and display driver integration (TDDI) solutions ... These new TDDI products add to the previously-announced ... TD4302 (WQHD resolution), and TD4322 (FHD resolution) solutions. ...
(Date:11/10/2015)... , Nov. 10, 2015  In this ... the basis of product, type, application, disease ... in this report are consumables, services, software. ... are safety biomarkers, efficacy biomarkers, and validation ... report are diagnostics development, drug discovery and ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... Calif. , Nov. 24, 2015 Cepheid ... will be speaking at the following conference, and invited ... New York, NY      Tuesday, December 1, 2015 ... New York, NY      Tuesday, December 1, 2015 ... Jaffray Healthcare Conference, New York, NY ...
(Date:11/24/2015)... , Nov. 24, 2015 /PRNewswire/ - Aeterna Zentaris ... of IIROC on behalf of the Toronto Stock Exchange, ... release there are no corporate developments that would cause ... --> --> About Aeterna ... www.aezsinc.com . --> Aeterna Zentaris is a ...
(Date:11/24/2015)... LEXINGTON, Massachusetts , November 24, 2015 ... Officer, will participate in the Piper Jaffray 27 th Annual ... on Tuesday, December 1, 2015, at 8:30 a.m. EST (1:30 p.m. ... Poulton , Chief Financial Officer, will participate in the Piper Jaffray ... City , NY on Tuesday, December 1, 2015, at 8:30 ...
(Date:11/24/2015)... ... November 24, 2015 , ... In harsh industrial processes, ... for in-line sensors can represent a weak spot where leaking process media is ... retractable sensor housings , which are designed to tolerate extreme process conditions. They ...
Breaking Biology Technology:
Cached News: