Three Dutch scientists are not convinced that the recently found bacterium which is able to thrive in a toxic environment loaded with arsenic, will change our views on life, as is suggested by the author of the article published in Science, 2 December.
In the publication it is suggested that the bacterium that was isolated from Mono Lake, California, is able to replace all of its phosphorus by arsenic. This would be a spectacular finding, as for the first time ever a living cell on earth would be identified which uses an element other than the six basic building blocks (carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur) to survive and evolve. Scientists Huisman, Matthijs and Bolhuis say, in last Saturday’s newspaper NRC in the Netherlands, that although being excited at first they think this bacterium is just another micro-organism that adapted to extreme circumstances via well-known mechanisms. After some calculations they concluded that although the bacterium is capable of replacing most of its phosphorus by arsenic, still 4 percent phosphorus is left in the cell. This makes it very likely that the DNA still only got phosphorus atoms next to the other building blocks, and only the rest of the cell contains arsenic. This suggests that the ‘novel’ bacterium still thrives and reproduces on the old regular components. So, our vision of life on earth survives?
Well, whatever can be said, it appears that some more research is necessary to convince the scientific community. Then again, let’s hope this is not a misleading research outcome, which is funded and planned by NASA to help them maintain and ensure their ‘search-for-life-in-outer-space’ projects.
(Source: NRC, 04.12.2010)
