chemistry2
maqi0912
speaklikeachemistry.docxMaterial need to watch:
1.https://www.youtube.com/watch?v=2c36SnVHuig
2.Chemistry – FoldIt
Four years of college. Four years of medical school. Three to eight years of 48 hour shifts in residency and internships. It takes many, many years of hard work to become a doctor. But what if I told you that you could help advance modern medicine with no medical training, while sitting at laptop eating cereal in your pajamas? I’m Megan Woltz and I’ll tell you how on this week’s Foundations of Science podcast.
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Retroviruses infect animal cells and can cause certain types of leukemia and auto-immune diseases like HIV. Scientists have spent a lot of time studying a particular retrovirus called Mason-Pfizer Monkey Virus, because it is it very similar to HIV. Studying the monkey virus helps scientist understand how HIV might be controlled.
Before retroviruses can copy themselves, they need a special protein, known as a protease, to modify the virus so that it can infect new cells. Some medicines work by binding to a protease so it can’t help the retrovirus copy itself and spread. But before scientists can make a medicine that can bind to a protease, they have to know what the protease looks like.
That’s harder than it sounds. The monkey virus protease is made up of a 114 tiny molecules called amino acids. Imagine a stretched-out string of 114 beads. If you ball up the string of beads in your hand, some beads that were originally far apart would now be much closer together. Some would be on the inside of the ball, some on the outside. You could ball up the string in a different way so that a different set of beads was on the inside. In fact, there are thousands of different ways you could rearrange the beads. It’s the same for a protein like the monkey virus protease. There are an unimaginable number of ways that the amino acid chain could be folded, but in reality it is always folded in the same way - into the most stable possible shape.
Scientists had been trying for more than 10 years to figure out how the monkey virus protease was folded. They had tried special computer programs that are supposed to predict the way proteins will fold based on how certain arrangements affect the stability of the shape. The program was able to find some very stable shapes, but not the one correct one.
That’s when scientists decided to turn to the best puzzle-solver of all: the human brain. People still have better spatial reasoning skills than computers, which basically means we’re better at solving 3D puzzles. The scientists put their best guess for the protein shape on an online game known as “Fold-It” that allows citizen scientists to virtually fold proteins in different ways. The players’ scores go up when they make a more stable protein and go down when they make a less stable one. People can play in teams, sharing ideas over online chats and improving on each other’s configurations. Different teams compete against each other to get the most stable protein.
In only 10 days, people playing Fold-It were able to figure out something very close to the best structure for the monkey virus protease – so close to it that scientists could go back to their toolboxes to work out the last few details. In 10 days citizen scientists playing a game accomplished something that laboratory researchers had been working on for more than 10 years!
Now that we know the shape of the monkey virus protease, scientists can begin developing drugs that will bind to it, which could lead to better drugs to control HIV. This major breakthrough for science and human medicine was made possible by citizen scientists putting their heads together, going to show that there is no substitute for human ingenuity and cooperation.
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If you’d like to play FoldIt and help scientists find the shapes for other important proteins involved in human diseases like cancer and alzheimer’s, go to FoldIt/portal. You can also play games to design RNA and to identify sections of DNA that may cause diseases.
If you’re more interested in exploring the outdoors than playing on your computer, you can find out about other cool citizen science projects related to everything from Archeology to Zoology at ScientificAmerican.com/citizen-science and SciStarter.com
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To learn more about how FoldIt works or to sign up to play, check out: http://fold.it/portal/
To design RNA molecules, check out eteRNA:
http://eterna.cmu.edu/web/
To search through DNA for sequences that may contribute to diseases, check out Phylo:
http://phylo.cs.mcgill.ca/#!/EN/about
To learn about other cool citizen science projects you could become involved in, including many that allow you to help collect cool data out in nature, check out:
Scientific American: http://www.scientificamerican.com/citizen-science/
Sci – Starter: http://www.scistarter.com/
Information reported in this podcast came from the links above and also from:
Baron, S (ed.). 1996. Medical Microbiology. 4th Ed. Ch 62 Human Retroviruses. University of Texas Medical Branch at Galveston, Galveston, TX.
http://www.ncbi.nlm.nih.gov/books/NBK7934/
MicrobeWiki page on Mason Pfizer Monkey Virus
http://microbewiki.kenyon.edu/index.php/Mason_pfizer_monkey_virus
Khatib, F. et al. 2011. Crystal structure of a monomeric retroviral protease solved by protein folding game players. Nature Structural and Molecular Biology
Boyle, A. 2011. Gamers solve molecular puzzle that baffled scientists. NBC News CosmicBlog.
One of the truisms in education is that you really know your stuff when you can teach it to someone else. The skill is very similar to the decoding that you did in the last module, but requires a bit more understanding and integration with what you already know.
Your Uncle Billy calls you saying he is thinking about moving to Los Angeles, but is worried about the air quality because he saw the following report. Report (from Chemistry and Physiology of Los Angeles Smog by Haagen-Smit)
Air pollution in the Los Angeles area is characterized by a decrease in visibility, crop damage, eye irritation, objectionable odor, and rubber deterioration. These effects are attributed to the release of large quantities of hydrocarbons and nitrogen oxides to the atmosphere. The photochemical action of nitrogen oxides oxidizes the hydrocarbons and thereby forms ozone, responsible for rubber cracking. Under experimental conditions, organic peroxides formed in the vapor phase oxidation of hydrocarbons have been shown to give eye irritation and crop damage resembling closely that observed on smog days.
· Explain the above description to your Uncle Billie in your own words, in a way that he (a barber from Okemos) would understand. Connect the concepts to at least a couple of ideas that Uncle Billy could reasonably know about.
· Compare and contrast the accuracy of your explanation with that of the original.
