Understanding through Discussion


Welcome! You are not logged in. [ Login ]
EvC Forum active members: 80 (8871 total)
Current session began: 
Page Loaded: 10-21-2018 7:52 AM
187 online now:
PaulK, Percy (Admin) (2 members, 185 visitors)
Chatting now:  Chat room empty
Newest Member: paradigm of types
Post Volume:
Total: 840,476 Year: 15,299/29,783 Month: 1,243/1,502 Week: 0/241 Day: 0/36 Hour: 0/0


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Prev12345
6
Author Topic:   Nasa news conference (re: Arsenic-based life form?)
Dr Jack
Member (Idle past 29 days)
Posts: 3507
From: Leicester, England
Joined: 07-14-2003


Message 76 of 78 (595035)
12-06-2010 11:10 AM
Reply to: Message 63 by Rrhain
12-04-2010 3:05 AM


Also, if you listen to what Wolfe-Simon actually said at the press conference she does flat out say that the bacterium is substituting Arsenic for Phosphorous even if the paper is more appropriately circumspect.
This message is a reply to:
 Message 63 by Rrhain, posted 12-04-2010 3:05 AM Rrhain has not yet responded

  
Rrhain
Member
Posts: 6349
From: San Diego, CA, USA
Joined: 05-03-2003


Message 77 of 78 (595321)
12-08-2010 2:22 AM


Here's another good description of why the paper is a stinker:

Arsenic-associated bacteria (NASA's claims)

But yes, the reporters were parroting the claim that the DNA had arsenate, falling down on the job. Now, I certainly don't expect reporters to be able to analyze a technically complex paper such as what was given, but I do expect them to consider the possibility that maybe, perhaps, somebody who does have the ability to analyze such things take a look and see what's going on.

Journalism has been reduced to stenography. And bad stenography at that, as reporters will make shit up in order to sell the story.


Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.
    
Wounded King
Member (Idle past 2019 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 78 of 78 (667529)
07-09-2012 6:57 AM


Contrary evidence
I know it has been a while since this was news but there were a couple of papers just published in Science which concerned this research.

One was from the lab of Rosemary Redfield, who was one of the more prominent blogosphere critics when the original paper came out and who Moose linked to upthread, there is a version of the paper at Arxiv (http://arxiv.org/abs/1201.6643) since the final Science version is behind a paywall. This paper tries to replicate some of the original's findings (albeit not with exactly the same methodology) but the results were inconsistent with Wolfe-Simon's hypothesis, finding no significant levels of covalently bound arsenate through mass-spec analysis. They did however find significant free arsenate which was removed by serial washes with distilled water, this supports Redfield's previous suggestions that the arsenate in Wolfe-Simon's results was contamination from the very arsenic rich growth medium the cells were cultured in. They also touch on the point the Mr Jack raised as to the stability of DNA incorporating arsenate being very prone to spontaneous hydrolysis by looking at the degradation of DNA from arsenic and non-arsenic containing media freshly isolated or after 2 months of storage, there was no appreciable increase in degradation in the samples from the arsenic rich medium.

The other paper (Erb et al., 2012) similarly used mass-spec, although a different form, to analyze nucleic acids from the Wolf-Simon bacterial strain under the conditions from her paper. As with Redfield's paper they did not find any more arsenic associated with the nucleic acids in the cells grown in the high arsenic medium than in ones grown with no arsenic.

TTFN,

WK


    
Prev12345
6
Newer Topic | Older Topic
Jump to:


Copyright 2001-2015 by EvC Forum, All Rights Reserved

™ Version 4.0 Beta
Innovative software from Qwixotic © 2018