Great!! Old Bucky created "Ice 9" before he died!!

----- Original Message -----
From: Russell McMahon <apptech@paradise.net.nz>
Date: Saturday, December 30, 2006 6:43 am
Subject: [EE]:: Buckyballs could disrupt DNA.
To: PIC List <PICLIST@mit.edu>

> 
> These results are from computer simulations but give cause for 
> concern.
> 
> 
>        
> http://electrons.psychogenic.com/modules/altern8news/article.php?
storyid=59
> New Scientist
> 
>        http://www.newscientist.com/article.ns?id=dn8439
> 
> Brightsurf
> 
>        
> http://www.brightsurf.com/news/headlines/view.article.php?
ArticleID=22037
> 
> 
> ______________________
> 
> "The binding energy between DNA and buckyballs is quite strong," 
> Cummings says. "We found that the energies were comparable to the 
> binding energies of a drug to receptors in cells."
> 
> It turns out that buckyballs have a stronger affinity for DNA than 
> they do for themselves. "This research shows that if buckyballs 
> can 
> get into the nucleus, they can bind to DNA," Cummings says. "If 
> the 
> DNA is damaged, it can be inhibited from self-repairing."
> 
> Computer simulations
> The computer simulations showed that buckyballs make first contact 
> with the DNA molecule after one to two nanoseconds. Once the C60 
> molecules bind with the DNA, they remained stable for the duration 
> of 
> the simulation.
> 
> Researchers tested the most common forms of DNA, the "A" and "B" 
> forms. The "B" form is the most common form. In a stronger saline 
> solution, or when alcohol is added, the DNA structure can change 
> to 
> the "A" form. A third, rarer form, "Z," occurs in high 
> concentrations 
> of alcohol or salt and was not tested.
> 
> The researchers found that buckyballs docked on the minor groove 
> of 
> "A" DNA, bending the molecule and deforming the stacking angles of 
> the 
> base pairs in contact with it. The simulations also showed that 
> buckyballs can penetrate the free end of "A" form DNA and 
> permanently 
> break the hydrogen bonds between the end base pair of nucleotides.
> 
> As expected, the buckyballs bound most strongly to single helix 
> DNA, 
> causing the most deformation and damage. While buckyballs did bind 
> to 
> "B" form double-strand DNA, the binding did not affect the overall 
> shape of the DNA molecule. More research needed
> 
> What the researchers don't know is whether these worrisome binding 
> events will take place in the body. "Earlier studies have shown 
> both 
> that buckyballs can migrate into bodily tissues and can penetrate 
> cell 
> membranes," Cummings says. "We don't know whether they can 
> penetrate a 
> cell nucleus and reach the DNA stored there. What this study shows 
> is 
> that if the buckyballs can get into the nucleus they could cause 
> real 
> problems. What are needed now are experimental and theoretical 
> studies 
> to demonstrate whether they can actually get there. Because the 
> toxicity of nanomaterials like buckyballs is not well known at 
> this 
> point, they are regarded in the laboratory as potentially very 
> hazardous, and treated accordingly."
> 
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