Bakteria hidup makan racun

chewan

Bakteria hidup makan racun

          
                  
                CALIFORNIA - Saintis Pentadbiran Aeronautik dan Angkasa Lepas Kebangsaan (Nasa) menemui sejenis bakteria yang mampu hidup dengan memakan bahan arsenik, Khamis lalu.

Penemuan mengejutkan itu bakal mengubah pemahaman manusia mengenai struktur biologi di bumi dan meningkatkan kemungkinan terdapat hidupan di angkasa lepas yang mampu hidup dengan bergantung kepada unsur kimia lain.

Menurut saintis, bakteria GFAJ-1 yang ditemui di Tasik Mono, California itu bukan sahaja boleh menerima arsenik, tetapi mampu  menggabungkan bahan beracun itu ke dalam DNA dan molekul penting lain bagi menggantikan penggunaan unsur fosforus.

Fosforus diketahui sebagai salah satu daripada enam unsur paling penting kepada hidupan di muka bumi selain karbon, oksigen, hidrogen, nitrogen dan sulfur.

Menurut saintis, ia adalah kali pertama dalam sejarah biologi sesuatu organisma mampu menggunakan unsur lain dalam struktur asasnya.

SHOnline

ea208964

Image of GFAJ-1 grown on arsenic.
Image Credit: Jodi Switzer Blum



Image of GFAJ-1 grown on phosphorus.
Image Credit: Jodi Switzer Blum

wah bila bagi arsenic makin sihat jadinya bacteria ni ...

artikel penuh ... kredit to http://www.nasa.gov/topics/universe/features/astrobiology_toxic_chemical.html

NASA-Funded Research Discovers Life Built With Toxic Chemical
12.02.10



NASA-funded astrobiology research has changed the fundamental knowledge about what comprises all known life on Earth.

Researchers conducting tests in the harsh environment of Mono Lake in California have discovered the first known microorganism on Earth able to thrive and reproduce using the toxic chemical arsenic. The microorganism substitutes arsenic for phosphorus in its cell components.

"The definition of life has just expanded," said Ed Weiler, NASA's associate administrator for the Science Mission Directorate at the agency's Headquarters in Washington. "As we pursue our efforts to seek signs of life in the solar system, we have to think more broadly, more diversely and consider life as we do not know it."

This finding of an alternative biochemistry makeup will alter biology textbooks and expand the scope of the search for life beyond Earth. The research is published in this week's edition of Science Express.

Carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur are the six basic building blocks of all known forms of life on Earth. Phosphorus is part of the chemical backbone of DNA and RNA, the structures that carry genetic instructions for life, and is considered an essential element for all living cells.

Phosphorus is a central component of the energy-carrying molecule in all cells (adenosine triphosphate) and also the phospholipids that form all cell membranes. Arsenic, which is chemically similar to phosphorus, is poisonous for most life on Earth. Arsenic disrupts metabolic pathways because chemically it behaves similarly to phosphate.

"We know that some microbes can breathe arsenic, but what we've found is a microbe doing something new -- building parts of itself out of arsenic," said Felisa Wolfe-Simon, a NASA Astrobiology Research Fellow in residence at the U.S. Geological Survey in Menlo Park, Calif., and the research team's lead scientist. "If something here on Earth can do something so unexpected, what else can life do that we haven't seen yet?"

The newly discovered microbe, strain GFAJ-1, is a member of a common group of bacteria, the Gammaproteobacteria. In the laboratory, the researchers successfully grew microbes from the lake on a diet that was very lean on phosphorus, but included generous helpings of arsenic. When researchers removed the phosphorus and replaced it with arsenic the microbes continued to grow. Subsequent analyses indicated that the arsenic was being used to produce the building blocks of new GFAJ-1 cells.

The key issue the researchers investigated was when the microbe was grown on arsenic did the arsenic actually became incorporated into the organisms' vital biochemical machinery, such as DNA, proteins and the cell membranes. A variety of sophisticated laboratory techniques was used to determine where the arsenic was incorporated.

The team chose to explore Mono Lake because of its unusual chemistry, especially its high salinity, high alkalinity, and high levels of arsenic. This chemistry is in part a result of Mono Lake's isolation from its sources of fresh water for 50 years.

The results of this study will inform ongoing research in many areas, including the study of Earth's evolution, organic chemistry, biogeochemical cycles, disease mitigation and Earth system research. These findings also will open up new frontiers in microbiology and other areas of research.

"The idea of alternative biochemistries for life is common in science fiction," said Carl Pilcher, director of the NASA Astrobiology Institute at the agency's Ames Research Center in Moffett Field, Calif. "Until now a life form using arsenic as a building block was only theoretical, but now we know such life exists in Mono Lake."

The research team included scientists from the U.S. Geological Survey, Arizona State University in Tempe, Ariz., Lawrence Livermore National Laboratory in Livermore, Calif., Duquesne University in Pittsburgh, Penn., and the Stanford Synchroton Radiation Lightsource in Menlo Park, Calif.

NASA's Astrobiology Program in Washington contributed funding for the research through its Exobiology and Evolutionary Biology program and the NASA Astrobiology Institute. NASA's Astrobiology Program supports research into the origin, evolution, distribution, and future of life on Earth.

bacteria82

Wow.. Ada juga bacteria mcm ni ye.. Thanks for the info

dauswq

Wow.. Ada juga bacteria mcm ni ye.. Thanks for the info
bacteria82 Post at 6-12-2010 09:00

<<-------- bacteria ni makan aper?

ea208964

Reply 3# bacteria82

mod bac ..dgn penemuan bactria mcm ni ..mungkin lps ni boleh jumpa kehidupan baru  .... cari kat tmpt selama ni diketepikan sbb selama ni scientists assume semua kehidupan perlu 6 unsur utama tu ... bacteria yg skrg kiranya bacteria yg tak baca manual kehidupan ... org cakap kena ada phosphorus baru boleh hidup ...bac ni cakap...teeeettt salah ... hehehee...

bacteria82

dauswq Post at 6-12-2010 10:26

Makan hati

bacteria82

Reply 5# ea208964
Yup.. Hm.. Banyak lagi ciptaan yang MAHA Esa yang mungkin belum kita semua ketahui..

auntie_girl

and maybe part ni kot yg penemuan barunya: The microorganism substitutes arsenic for phosphorus in its cell components.plus part ni:Menurut saintis, ia adalah kali pertama dalam sejarah biologi sesuatu organisma mampu menggunakan unsur lain dalam struktur asasnya.

ea208964

Reply 8# auntie_girl

and maybe part ni kot yg penemuan barunya: The microorganism substitutes arsenic for phosphorus in its cell components.plus part ni:Menurut saintis, ia adalah kali pertama dalam sejarah biologi sesuatu organisma mampu menggunakan unsur lain dalam struktur asasnya

tak silap yg dorang excited sbb ni lah kan ...bukan pasal penggunaan arsenic   tapi kebolehan bacteria tu guna arsenic tuk produce cell baru ...  membesar bagai johan walaupun salah satu drp   6 unsur penting tu MIA



* thanks chewan ...

auntie_girl

Reply  auntie_girl



tak silap yg dorang excited sbb ni lah kan ...bukan pasal penggunaan arse ...
ea208964 Post at 7-12-2010 16:21

    yerp..yerp...     kalo setakat guna bakteria utk remove arsenic,lama dah org buat

auntie_girl

sekarang ni,apakah jenis bakteria itu? bakteria tu baik ke bakteria jahat?

ea208964

Reply 11# auntie_girl


    tu pulak persoalan nya ..bacteria ni akan membantu kehidupan atau akan memmusnahkan kehidupan .... klu nak kira ni hardcore nya bacteria .. letaklah kat mana pon boleh survive ...aad phsoporus pon boleh hidup ...xde pon boleh hidup ...