Replication of arsenic life experiment not successful so far

Aug 11, 2011 By Nancy Atkinson
A replication of the arsenic life experiment being done by biologist Rosie Redfield. Credit: Rosie Redfield.

One of the most vocal and ardent critics of the so-called 'arsenic life' experiment which was published in December 2010 was biologist Rosie Redfield from the University of British Columbia in Vancouver. The science paper by NASA astrobiologist Felisa Wolfe-Simon and her team reported that a type of bacteria in Mono Lake in California can live and grow almost entirely on arsenic, a poison, and incorporates it into its DNA. Redfield called the paper “lots of flim-flam, but very little reliable information.” Her opinion was quickly seconded by many other biologists/bloggers.

Redfield has been working on replicating the experiment done by Wolfe-Simon, and doing in her work in front of the world, so to speak. She is detailing her work in an open lab notebook on her blog. So far, she reports that her results contradict Wolfe-Simon et al.’s observations.

To date, Redfield is finding that the , called GFAJ-1, is not living and growing in arsenic, but dying. Redfield says her work refutes that cells from the GFAJ-1 could use arsenic for growth in place of phosphorus, and when arsenic was added to the low-phosphorus medium in which the bacteria was living, the bacteria was killed. Additionally, in other test viles, the growth properties Redfield is finding for GFAJ-1 don’t match those reported by Wolfe-Simon and her team, which claimed that the bacteria could not grow on a low concentration of phosphorus, and that the bacteria could grow on arsenic in the absence of phosphorus.

Redfield’s two major early criticisms of the original paper were that the authors had not ruled out the possibility that the bacteria were feeding on phosphorus contaminating their growth medium; and that the bacterial DNA was not properly purified, so that the arsenic detected might not actually have been in .

An article in Nature reports that other researchers also working on replicating the experiment with GFAJ-1 laud Redfield’s efforts, but say it is too early to conclude that she has debunked the original work.

Additionally, one problem is that Redfield she did not replicate the experiment exactly, as she had to add one nutrient not used by the authors of the original arsenic life paper in order for the bacteria to grow.

This is not the first time scientists have written open notebooks during the replication of controversial findings, but it might be one of the more notable, given the amount of media attention the life paper received.

Redfield is also hoping that her work will highlight the benefits of open notebook-type research.

You can read Redfield’s blog about her work at this link.

Explore further: Parasitic worm genomes: largest-ever dataset released

add to favorites email to friend print save as pdf

Related Stories

Critics raise doubts on NASA's arsenic bacteria

Dec 09, 2010

(PhysOrg.com) -- NASA’s announcement last week that bacteria had been discovered that appeared to replace phosphorus with arsenic and thrive even in the most poisonous environments, has now come under ...

NASA's arsenic life-form scientist answers critics

Dec 16, 2010

The NASA-funded scientist whose discovery of a bacterium that thrives on arsenic prompted an avalanche of criticism responded Thursday with a statement answering questions about her research. ...

NASA's arsenic-eating life form gets a second look

Dec 15, 2010

Soon after NASA-funded researchers announced this month they had found a new life form that thrives on arsenic, critics took to the blogosphere with skeptical views and downright insults. ...

Searching for Alien Life, on Earth

Oct 05, 2009

If you spend an afternoon walking along the muddy shore of Mono Lake, with the eastern flank of the Sierra Nevada mountains looming majestically in the background, you’ll no doubt discover, as others have ...

LU researcher: NASA's ET hype does disservice to science

Dec 13, 2010

NASA researchers recently unveiled a major discovery -- the first identified microorganism on Earth able to thrive using toxic arsenic rather than phosphorus, which forms the DNA-backbone of all other living things. But now, s ...

Recommended for you

Parasitic worm genomes: largest-ever dataset released

8 hours ago

The largest collection of helminth genomic data ever assembled has been published in the new, open-access WormBase-ParaSite. Developed jointly by EMBL-EBI and the Wellcome Trust Sanger Institute, this new ...

Bitter food but good medicine from cucumber genetics

Nov 27, 2014

High-tech genomics and traditional Chinese medicine come together as researchers identify the genes responsible for the intense bitter taste of wild cucumbers. Taming this bitterness made cucumber, pumpkin ...

New button mushroom varieties need better protection

Nov 27, 2014

A working group has recently been formed to work on a better protection of button mushroom varieties. It's activities are firstly directed to generate consensus among the spawn/breeding companies to consider ...

Cataloguing 10 million human gut microbial genes

Nov 25, 2014

Over the past several years, research on bacteria in the digestive tract (gut microbiome) has confirmed the major role they play in our health. An international consortium, in which INRA participates, has developed the most ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

alanborky
not rated yet Aug 12, 2011
"one problem is that Redfield she did not replicate the experiment exactly, as she had to add one nutrient not used by the authors of the original arsenic life paper in order for the bacteria to grow."

Talk about your flim-flam!

First replicate the original experiment: if you can't, use that to discredit it - but DON'T CLAIM AN EXPERIMENT WITH DIFFERENT PARAMETERS DISCREDITS ANOTHER EXPERIMENT YOU CLEARLY SET OUT TO DISCREDIT FROM THE BEGINNING, (rather than scientifically and open mindedly set out to test the veracity of)!

I can see a new 'reality' TV show emerging out of this growing trend of scientific priesthoods setting out to smear each others reputations instead of their actual work: SCIENCE WARS, (on the lines of Robot Wars).

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.