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Hello People of TWIV!
Thanks for all the information you give and how you make me think. I really liked your discussions on TWIV 136 - exit XMRV, not as much for the science ( which was cool) but for the discussion of the process of science - how it is not as linear as we often teach our students. I wish all my students could have heard this discussion, but I think many would get lost in the vocabulary of XMRV.
I am a high school science teacher, previously a lab rat in biotech labs (I started in 1975, so I learned to do things without kits, and I remember when getting a milligram of plasmid from a liter of LB was a glorious thing - now they get that from a miniprep!)
The hardest thing for kids to understand is how science works. There is a great website
Understanding Science http://undsci.berkeley.edu/
which greatly helps. Judy Scotchmore and other people in the Museum of Paleontology at Berkeley continue to work on the this site, adding real world examples of science, both good and bad, student misconceptions, and lesson plans for teachers through college. They have also reordered the classic "scientific method" 6 step list into a more realistic (and interactive) circular form check out "how science works - The flowchart" . They also have a 'science checklist' to help kids understand what science is - and what it's not.I do have a request for you and for all the scientists who listen to TWIV - part of the website ( under resources tab) is a section called "the call of science" where scientists talk about how they became scientists. You guys need to put your stories there and share you love of communication of science - after all - you are the cutting edge of how science information can be shared with the general public.
Thanks for all you do - and all the work you put in. I learn much from TWIV, TWIM and TWIP..... and I may be in a minority here, but please don't add more episodes - if you do I'll have to quit my job to keep up! (Actually, more TWIPs would be fun - monster stories on a small scale!)
Thanks for being MY teacher!
San Diego, CA
(70s and Sunny.. that's about 22 degrees C!)
At TWiV 139 you discussed how after several passages in amoebal cultures the Mimivirus gets bald and loses a big chunk of DNA. This reminded me of a Annual Review about this virus that I read some time ago (reference here), where Claverie and Albergel mention that the Mimivirus fibers serve to mimic the bacteria that are preyed by the acanthamoeba and to be phagocyted. These fibers are even glycosilated to better copy the bacteria and can retain Gram staining, which is the source of confusion behind the discovery of this virus. So, it is not a big surprise that the disappearance of the fibers is followed by the lost of the sugar related genes, it could be that this amoeba used to culture the virus does not need the coating in order to be infected.
The hole story behind the discovery of Mimivirus is due to its resemblance to bacteria. I don't remember if you have talked about it already, so here goes a brief description. Mimivirus was mistook as a gram-negative intracellular bacterium, during the analysis of a water sample from a cooling tower in search for Legionella. It could be stained and observed inside amoebas, but it could not be cultured, and ribosomal 16s primers didn't work for them. According to the discoverers "Among all the intra-amoebal “bacteria” that constituted our original collection, one provided us with the most headaches but, ultimately, the most exciting findings." When they looked at these bacteria under a electronic microscope, they saw the unmistakable icosahedral form of a virus, but a giant one. The name also came from a curious source "We have proposed the name Mimivirus , partially as a reflection of its mimicry of microbes and partially as a tribute to one of our forefathers (D.R.), who was a doctor who taught tropical medicine and studied nutrition. When teaching his 10-year-old son about evolution, he referred to the last eukaryotic common ancestor as 'Mimi the amoeba.'"
As for the complexity in biology that always comes up in discussions, there's a nice passage from "The Great Influenza", a book that you recommended in TWiV 15: "Leo Szilard, a prominent physicist, made this point when he complained that after switching from physics to biology he never had a peaceful bath again. As a physicist he would soak in the warmth of a bathtub and contemplate a problem, turn it in his mind, reason his way through it. But once he became a biologist, he constantly had to climb out of the bathtub to look up a fact."
Sorry about the long mail, full of quotes about things you already have discussed, but I love when you talk about other viruses besides those that make you sick. I like the ones about disease causing viruses too, but discussions of viruses outside the realm of human disease are rare, and being able to hear them from you and your guests is a great opportunity.
I would also ask you to forgive my bad english again but, as Alan says, you don't speak portuguese very well too. So thanks again for the rich and informative podcast(s), from one of your many Brazilian listeners.
My dear TWiVists!
We have three brilliant shows. We have TWiV. We have TWiP. And now we have TWiM. How long before TWiF makes an appearance? Let's not leave our fine fungal friends in the dark!
Keep up the fantastic work. You guys are a valuable resource for a kid who did humanities in high school and is trying to add to his scientific understanding during uni, before eventually applying for med school!
Much love and respect,
I'm a long time listener, first time email-er. I really love the show!
I was really intrigued by this weeks show on XMRV (TWIV #136). I wonder how frequently recombination resuscitates endogenous retroviruses in nature, away from the contrivances of the laboratory (ie. propagating human prostate cancer cells in mice). Do you think that Human Endogenous Retroviruses (HERVs) are frequently revived in children whose parents both carry inactive retroviruses? If each parent carried a similar retroviruses that are inactive due to loss of genetic information in different portions of the retrovirus, there might a potential for the retroviruses to recombine and become active again once they are united within a new individual genome (that of the child).
Thanks for the enlightening, inspiring, and entertaining podcasts!