The mankind will realize or the great change will happen the life

The mankind will realize or the great change will happen the life
Washington, December 2 (Xinhua) talk about arsenic element, the possibility that most people expect at first is its virulent compound - -Arsenicum. The scientist of American space agency announced on the 2nd, they found a kind of unique bacterium newly, can make use of arsenic to replace phosphorus element and construct the life molecule, reflect some key biochemistry. This finds that forming the basic element of the life can be replaced by other elements for the first time. If further confirmed, should find that will bring about the great change in human understanding of life, widen the thinking that and even the exterior celestial body looks for the life in extreme environment of the earth. Carbon, hydrogen, oxygen, nitrogen, phosphorus, sulphur make up the six basic elements of the life on earth. Phosphorus element plays an extremely important role in cells, include keeping the skeleton, participation of the hereditary material DNA and RNA forming the cell membrane, with ATP (ATP) The form of the molecule transports energy,etc.. But scientist fee Lisa and Wolff - Simon,et al. of the American space agency find, this kind of position of phosphorus can be replaced. They deliver a report saying on the network edition of Science, a kind of bacterium living in the not promise lake in the east in California in U.S.A., can make use of arsenic to finish these functions instead of phosphorus. Because the mineral of surrounding area is rich in arsenic, promise that don't arsenic on lake is extremely tall in density. The scientist gathers the silt from the lakebed, train with high arsenic low phosphorus artificial salt, then carry on, dilute the course while being a series of, try hard to remove phosphorus left in solutions, replace with arsenic. Found finally, growing situation of a kind of bacterium was obviously better than other bacteria. It verifies, this kind of bacterium's growth speed in arsenic solution, can reach 60% of the growth speed in phosphorus solution to separate and train. If the environment hits and theres is neither phosphorus nor arsenic, it is totally unable to grow. This kind of bacterium is known as GFAJ-1, it is a salt form afterbirth fungus department on the fungus door out of shape. The radioactive mark indicates, arsenic element exists in many kinds of important parts of this kind of bacterium, including protein, fat, ATP, forming nucleotide of DNA and RNA. Spectral analysis reveals indirectly, in DNA skeleton, arsenic has replaced the role of phosphorus. Wolff - Simon says, the data support this kind of bacterium to substitute the view of phosphorus with arsenic strongly. She thinks, if can accomplish this as to the common salt form afterbirth fungus, perhaps other bacteria can accomplish, this may show an unseen before world to people. In the periodic table of elements, arsenic is arranged below phosphorus, the two are the consanguinity, the chemical property is similar. In fact, arsenic exactly comes from this to poisonous to most living beings, it can " kidnap " Biochemistry of participation of phosphorus reacts, stir up confusion. Once found that there are microorganisms that can make use of arsenic compound to carry on the photosynthesis before this, but this is that the discovery forms the living beings of the basic molecule of life with arsenic directly for the first time. People have imagined for a long time, the basic element of life can be replaced by other elements, it is central to replace carbon element with element silicon as the life molecule " The silicon base life " Appear in a lot of science fiction works. Newly discovered bacterium illustrating actually first similar to imagine, but because the intersection of phosphorus and importance in life compare with carbon element, this kind of bacterium is unsuitable to be known as " The arsenic base life " .

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