Posted by Randal on August 25, 2002, at 22:37:40
In reply to Re: Supplements, Jokes, and a Question » Randal, posted by IsoM on August 25, 2002, at 1:10:54
> Don't worry, Randal, I'm not that sensitive, I was joking - that's why I put in the silly smilie ^_^
> Sadly, many of these bogus supplements are sold in pharmacies, sitting alongside helpful supplements, adding some credence to the idea of their uselfulness.
>
> To be honest, what you do sounds better than simply teaching (though I know there are few professors who only teach). A question for you:
>
> I know there are thousands of different proteins in the body, all with their own unique 3D structure. As you know, the folding of a chain of thousands of amino acids into its final tertiary or quaternary structure involves many foldings (& unfoldings) along the way. Do you think it'll ever become possible for scientists to discover a way to find out what all the steps to the final structure are? It's one thing to unfold (denature) a protein, but entirely another to know what was involved initially.
>
> Excuse me if I haven't worded the question peoperly, but I hope you understand it. It seems the more I've learned, the more questions I've got. I wish I could pick someone's brains each time I wonder about something & can't find an answer.That's a very active field of research, and there has been a lot of progress in understanding things. Here's a simplified view: The overall process seems to involve a rapid formation of secondary structure (alpha helices and beta sheet). This collapses into the compact "correct" structure, which can occur with or without intermediates. The steps in the folding pathway have been delineated for a number of proteins. In a cell, of course, things can be somewhat different, since the protein (or pieces of it) may be folding while the polypeptide chain is still being extruded from the ribosome. Additionally, the folding of many proteins in the cell, especially large ones, is actually assisted by other proteins (called "chaperones").
Here's a couple references if you can retrieve them:
S.E. Radford, "Protein folding: progress made and promises ahead" Trends in Biochemical Sciences 25 (12): 611-618 DEC 2000.
D. Baker "A surprising simplicity to protein folding" NATURE 405 (6782): 39-42 MAY 4 2000.
But this is getting WAY off topic. In an attempt to bring it back at least a little bit, I'll mention that many neurodegenerative diseases, such as Alzheimer's and BSE (mad cow disease), are associated with the misfolding and aggregation of proteins. So finding drugs that can inhibit or reverse the misfolding is a big priority.
A reference: Taylor, et al. "Toxic proteins in neurodegenerative disease" SCIENCE 296 (5575): 1991-1995 JUN 14 2002.
poster:Randal
thread:111261
URL: http://www.dr-bob.org/babble/20020821/msgs/117749.html