Quantcast
ZME Science
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
    Menu
    Natural Sciences
    Health
    History & Humanities
    Space & Astronomy
    Technology
    Culture
    Resources
    Natural Sciences

    Physics

    • Matter and Energy
    • Quantum Mechanics
    • Thermodynamics

    Chemistry

    • Periodic Table
    • Applied Chemistry
    • Materials
    • Physical Chemistry

    Biology

    • Anatomy
    • Biochemistry
    • Ecology
    • Genetics
    • Microbiology
    • Plants and Fungi

    Geology and Paleontology

    • Planet Earth
    • Earth Dynamics
    • Rocks and Minerals
    • Volcanoes
    • Dinosaurs
    • Fossils

    Animals

    • Mammals
    • Birds
    • Fish
    • Reptiles
    • Amphibians
    • Invertebrates
    • Pets
    • Conservation
    • Animals Facts

    Climate and Weather

    • Climate Change
    • Weather and Atmosphere

    Geography

    Mathematics

    Health
    • Drugs
    • Diseases and Conditions
    • Human Body
    • Mind and Brain
    • Food and Nutrition
    • Wellness
    History & Humanities
    • Anthropology
    • Archaeology
    • Economics
    • History
    • People
    • Sociology
    Space & Astronomy
    • The Solar System
    • The Sun
    • The Moon
    • Planets
    • Asteroids, Meteors and Comets
    • Astronomy
    • Astrophysics
    • Cosmology
    • Exoplanets and Alien Life
    • Spaceflight and Exploration
    Technology
    • Computer Science & IT
    • Engineering
    • Inventions
    • Sustainability
    • Renewable Energy
    • Green Living
    Culture
    • Culture and Society
    • Bizarre Stories
    • Lifestyle
    • Art and Music
    • Gaming
    • Books
    • Movies and Shows
    Resources
    • How To
    • Science Careers
    • Metascience
    • Fringe Science
    • Science Experiments
    • School and Study
    • Natural Sciences
    • Health
    • History and Humanities
    • Space & Astronomy
    • Culture
    • Technology
    • Resources
  • Reviews
  • More
    • Agriculture
    • Anthropology
    • Biology
    • Chemistry
    • Electronics
    • Geology
    • History
    • Mathematics
    • Nanotechnology
    • Economics
    • Paleontology
    • Physics
    • Psychology
    • Robotics
  • About Us
    • About
    • The Team
    • Advertise
    • Contribute
    • Privacy Policy
    • Contact
No Result
View All Result
ZME Science

No Result
View All Result
ZME Science

Home → Science → Biology

Debunking Arsenic life: bacterium prefers phosphorous after all

Mihai Andrei by Mihai Andrei
October 4, 2012
in Biology, Chemistry

Remember when, in 2010, we told you about a team of researchers which claimed they found a bacteria that feasts on arsenic, instead of phosphorous? The study has spurred quite the discussion, receiving a lot of both criticism and praise, but seeming to be, ultimately, incorrect (as this other study also claims). Dan Tawfik, who studies protein function at the Weizmann Institute of Science in Rehovot, Israel, put the final nail in the theory’s coffin.

The main ingredients for life

Oh well…
Source

Currently, life as we know it requires six elements to survive (CHNOPS): Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, and Sulfur. Practically over 98% of all dry organic matter is made from these elements. Arsenic is chemically somewhat similar to sulfur, but it’s actually very poisonous to most life, so finding a bacteria that relies on it to survive could essentially change the way we understand life itself; obviously this is a big thing.

After the initial momentum passed, the theory started losing ground and started being attacked, so that after a year, few believed it to be correct. The bacteria, (GFAJ-1 microbe) became boring. But biology is never boring – life is never boring, and a key question remained: how does GFAJ-1 differentiate between nearly identical molecules of phosphate (PO43-) and arsenate (AsO43-).

Arsenic vs phosphorous: a chemical bond

Professor Dan Tawfik and his team dug deep and found what makes bacteria attach to phosphorous molecules and avoid arsenic ones, suggesting that a single chemical bond holds the key.

“This work provides in a sense an answer to how GFAJ-1 (and related bacteria) can thrive in very high arsenic concentrations,” say Tobias Erb and Julia Vorholt of the Swiss Federal Institute of Technology in Zurich, co-authors of the latest paper, who were also co-authors on a follow-up paper that cast doubt on the initial arsenic-life claims.

The team analyzed five types of phosphate-binding protein from four different bacteria species; out of four, two were resistant to arsenic and two were highly sensitive to it. In order to study just how good these bacteria are at differentiating between molecules, they were placed in a solution with a set amount of phosphate and different concentrations of arsenate for 24 hours and then checked which molecules they naturally bound to.

When 50% of the proteins ended up bound to arsenate, it was clear the ability to differentiate had been overwhelmed. Even when there was 500 times more arsenic than phosphorous molecules, all four species were still able to differentiate and bound to the right molecules. As a matter of fact, the one from Mono Lake, which sparked the original study, was able to do so even at arsenate excesses of up to 4,500-fold over phosphate.

Tawfik says that he was shocked by how good bacteria are at extracting the necessary phosphorous while rejecting the deadly arsenic; however, this doesn’t show bacteria is arsenate-free.

“It just shows that this bacterium has evolved to extract phosphate under almost all circumstances.”

Arsenate monster actually hates arsenate

The Arsenate monster, as the GFAJ-1 bacteria was jokingly called by some biologists actually goes to a huge amount of effort to actually avoid arsenic – clearly showing that it doesn’t like the element inside its cytoplasm.

Felisa Wolfe-Simon, lead author on the original Science paper and now at Lawrence Berkeley National Laboratory in Berkeley, California showed an extremely positive fair play attitude, explaining “represents the kind of careful study that really helps the community”. However, we mustn’t reject novel ideas such as the one she proposed – it’s this kind of study which push the scientific boundaries most, be it to confirm or disprove them.

Scientific source

Was this helpful?


Thanks for your feedback!

Related posts:
  1. There are arsenic-breathing microbes in the tropical Pacific, a new study finds
  2. Canadian Arctic bacterium offers clues to life on Mars
  3. NASA’s conference on arsenic eating microbe that could rewrite biology books
  4. Villagers high in the Andes have developed a genetic tolerance to arsenic
  5. Water wells serving 2 million Americans could be contaminated with high levels of Arsenic
Tags: arsenicarsenic-based lifebacteriachemical bondgfaj-1

ADVERTISEMENT
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
  • Reviews
  • More
  • About Us

© 2007-2021 ZME Science - Not exactly rocket science. All Rights Reserved.

No Result
View All Result
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
    • Natural Sciences
    • Health
    • History and Humanities
    • Space & Astronomy
    • Culture
    • Technology
    • Resources
  • Reviews
  • More
    • Agriculture
    • Anthropology
    • Biology
    • Chemistry
    • Electronics
    • Geology
    • History
    • Mathematics
    • Nanotechnology
    • Economics
    • Paleontology
    • Physics
    • Psychology
    • Robotics
  • About Us
    • About
    • The Team
    • Advertise
    • Contribute
    • Privacy Policy
    • Contact

© 2007-2021 ZME Science - Not exactly rocket science. All Rights Reserved.

Don’t you want to get smarter every day?

YES, sign me up!

Over 35,000 subscribers can’t be wrong. Don’t worry, we never spam. By signing up you agree to our privacy policy.

✕
ZME Science News

FREE
VIEW